[ { "path": ".editorconfig", "content": "root = true\n\n[*]\nindent_style = tab\nend_of_line = lf\ncharset = utf-8\ntrim_trailing_whitespace = true\ninsert_final_newline = true\n\n[*.yml]\nindent_style = space\nindent_size = 2\n" }, { "path": ".gitattributes", "content": "* text=auto eol=lf\n" }, { "path": ".github/ISSUE_TEMPLATE/1 new type.yml", "content": "name: 💡 Suggest new type\ndescription: '​‌‍⁠ ' # Magic whitespace to hide this required field\nlabels: 'type addition'\n\nbody:\n - type: textarea\n id: description\n validations:\n required: true\n attributes:\n label: Type description + examples\n\n - type: textarea\n id: type\n attributes:\n label: Type source\n description: If you already have the type source, enter it here as a starting point for a the discussion\n\n - id: requirements\n type: checkboxes\n attributes:\n label: Search existing types and issues first\n options:\n - label: I tried my best to look for it\n required: true\n" }, { "path": ".github/ISSUE_TEMPLATE/2 bug report.yml", "content": "name: 🐛 Report bug\ndescription: '​‌‍⁠ ' # Magic whitespace to hide this required field\nlabels: bug\n\nbody:\n - type: textarea\n id: description\n validations:\n required: true\n attributes:\n label: Bug description\n\n - type: input\n id: repro\n validations:\n required: true\n attributes:\n label: Repro\n description: |\n Open [this playground](https://www.typescriptlang.org/play/?#code/JYWwDg9gTgLgBDAnmApnA3gUQB4GMVgwC+cAZlBCHAORKoC0pKAzjNQNwCwAUD3WgDEIEOAF4MPAJABXAHbBc0WQC44rKMFkBzLt0lQAhpoBGEAO6rTEADYoDs3UV19kaAHIQASkdmmzYuBx8QgAeIQgAGhpDE3NqAD5dOGS4AHpUuAA9AH4eIA), write a piece of code that fails your expectations, click \"Share\", and paste the URL here\n" }, { "path": ".github/ISSUE_TEMPLATE/3 enhancement.md", "content": "---\nname: ♻️ Propose change or improvement to existing types\nabout: '​‌‍⁠ ' # Magic whitespace to hide this required field\nlabels: 'enhancement'\n---\n" }, { "path": ".github/contributing.md", "content": "# Contributing guidelines\n\n## Submitting a new type\n\n- One type addition per pull request, unless they are connected.\n- **Please help review the other open pull requests.**\n\t- If there are no open pull requests, provide some feedback on some of the open issues.\n- [Example of a type contribution.](https://github.com/sindresorhus/type-fest/commit/5374588a88ee643893784f66367bc26b8e6509ec)\n- Create a new file in the `test-d` directory and write at least one type test.\n\t- See the other tests for inspiration.\n\t- If it makes sense, also write a negative test using [`expectNotAssignable()`](https://github.com/SamVerschueren/tsd#expectnotassignabletexpression-any) or, to test other diagnostics, [`expectError()`](https://github.com/SamVerschueren/tsd#expecterrort--anyexpression-t).\n- Don't use one-character type names like `T` and `U`. Use descriptive names. See the existing types for inspiration.\n- Follow the existing code style, even in documentation code examples.\n\t- Don't prefix each line in documentation comments with `*`.\n- Write a good documentation comment that includes:\n\t- Write a short and clear description of what the type does.\n\t\t- The first line should match the description in the readme.\n\t- Write about some real-world use-cases where it can be useful. (It can be hard sometimes for users to see where they would use something)\n\t- Example code block with a realistic example.\n\t- At the bottom, explain how the type works. Some types can be quite advanced and hard to understand. We can use this opportunity to teach users.\n\t- If there has been any discussion somewhere about this type, include a link to it. For example, a discussion on the TypeScript issue tracker.\n\t- Add relevant `@category` tags. See other types for examples.\n- If you add any internal helper types, they should still be properly documented and tested.\n- Add the type to the readme.\n- Make sure the file in the `source` directory uses a `.d.ts` extension and not `.ts`.\n- **Use AI (like ChatGPT) to catch type bugs, improve docs, spot typos, validate examples, and suggest more tests.** Include all relevant code (type, tests, helpers, etc.) in the prompt, and also provide a couple of existing types as examples of how it's done. Try this prompt: “Review this TypeScript type for correctness, edge cases, naming, docs, and test coverage. Suggest improvements and realistic succinct examples.”\n- Run `$ npm test` before submitting and make sure it passes.\n- Name the pull request ```Add `TypeName` type```.\n" }, { "path": ".github/dependabot.yml", "content": "version: 2\nupdates:\n - package-ecosystem: 'github-actions'\n directory: '/'\n schedule:\n interval: 'weekly'\n groups:\n github-actions:\n patterns:\n - '*'\n - package-ecosystem: 'npm'\n directory: '/'\n schedule:\n interval: 'monthly'\n versioning-strategy: 'increase-if-necessary'\n groups:\n development-dependencies:\n dependency-type: 'development'\n" }, { "path": ".github/funding.yml", "content": "github: [sindresorhus, som-sm, Emiyaaaaa, voxpelli]\n" }, { "path": ".github/pull_request_template.md", "content": "\n" }, { "path": ".github/security.md", "content": "# Security Policy\n\nTo report a security vulnerability, please use the [Tidelift security contact](https://tidelift.com/security). Tidelift will coordinate the fix and disclosure.\n" }, { "path": ".github/workflows/claude-code-review.yml", "content": "name: Claude Code Review\non:\n pull_request:\n types: [opened, synchronize]\njobs:\n claude-review:\n runs-on: ubuntu-latest\n # Only run if the PR is from the same repository (not a fork), because forks are not supported yet: https://github.com/anthropics/claude-code-action/issues/339\n if: github.event.pull_request.head.repo.full_name == github.repository\n permissions:\n contents: read\n pull-requests: write\n issues: read\n id-token: write\n steps:\n - name: Checkout repository\n uses: actions/checkout@v5\n with:\n fetch-depth: 1\n - name: Run Claude Code Review\n id: claude-review\n uses: anthropics/claude-code-action@v1\n with:\n claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}\n prompt: |\n REPO: ${{ github.repository }}\n PR NUMBER: ${{ github.event.pull_request.number }}\n\n Please review this pull request and provide feedback on:\n - Code quality and best practices\n - Potential bugs or issues\n - Performance considerations\n - Security concerns\n - Test coverage\n - Be succinct\n - Only comment about things that needs to be fixed/improved\n - Review thoroughly\n\n Use the repository's CLAUDE.md for guidance on style and conventions. Be constructive and helpful in your feedback.\n\n Use `gh pr comment` with your Bash tool to leave your review as a comment on the PR.\n\n # See https://github.com/anthropics/claude-code-action/blob/main/docs/usage.md\n # or https://docs.claude.com/en/docs/claude-code/sdk#command-line for available options\n claude_args: '--allowed-tools \"Bash(gh issue view:*),Bash(gh search:*),Bash(gh issue list:*),Bash(gh pr comment:*),Bash(gh pr diff:*),Bash(gh pr view:*),Bash(gh pr list:*)\"'\n" }, { "path": ".github/workflows/claude.yml", "content": "name: Claude Code\non:\n issue_comment:\n types: [created]\n pull_request_review_comment:\n types: [created]\n issues:\n types: [opened, assigned]\n pull_request_review:\n types: [submitted]\njobs:\n claude:\n if: |\n (github.event_name == 'issue_comment' && contains(github.event.comment.body, '@claude')) ||\n (github.event_name == 'pull_request_review_comment' && contains(github.event.comment.body, '@claude')) ||\n (github.event_name == 'pull_request_review' && contains(github.event.review.body, '@claude')) ||\n (github.event_name == 'issues' && (contains(github.event.issue.body, '@claude') || contains(github.event.issue.title, '@claude')))\n runs-on: ubuntu-latest\n permissions:\n contents: read\n pull-requests: read\n issues: read\n id-token: write\n actions: read # Required for Claude to read CI results on PRs\n steps:\n - name: Checkout repository\n uses: actions/checkout@v4\n with:\n fetch-depth: 1\n - name: Run Claude Code\n id: claude\n uses: anthropics/claude-code-action@v1\n with:\n claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}\n additional_permissions: |\n actions: read\n" }, { "path": ".github/workflows/main.yml", "content": "name: CI\non:\n push:\n branches:\n - main\n tags:\n - '*'\n pull_request:\n branches:\n - main\njobs:\n test:\n name: Node.js ${{ matrix.node-version }}\n runs-on: ubuntu-latest\n strategy:\n fail-fast: false\n matrix:\n node-version:\n - 24\n - 22\n - 20\n steps:\n - uses: actions/checkout@v5\n - uses: actions/setup-node@v5\n with:\n node-version: ${{ matrix.node-version }}\n - run: npm install\n - run: npm test\n types:\n name: TypeScript ${{ matrix.typescript-version }}\n runs-on: ubuntu-latest\n strategy:\n fail-fast: false\n matrix:\n typescript-version:\n - 'latest'\n - '~5.9.0'\n steps:\n - uses: actions/checkout@v5\n - uses: actions/setup-node@v5\n with:\n node-version: 24\n - run: npm install\n - run: npm install typescript@${{ matrix.typescript-version }}\n - run: NODE_OPTIONS=\"--max-old-space-size=6144\" npx tsc\n" }, { "path": ".github/workflows/ts-canary.yml", "content": "name: TypeScript Canary\non:\n schedule:\n # Every Thursday at 21.15\n - cron: '15 21 * * 4'\n workflow_dispatch:\njobs:\n types:\n name: TypeScript ${{ matrix.typescript-version }}\n runs-on: ubuntu-latest\n strategy:\n fail-fast: false\n matrix:\n typescript-version:\n - next\n - latest\n steps:\n - uses: actions/checkout@v5\n - uses: actions/setup-node@v5\n with:\n node-version: lts/*\n - run: npm install\n - run: npm install typescript@${{ matrix.typescript-version }}\n - name: show installed typescript version\n run: npm list typescript --depth=0\n - run: NODE_OPTIONS=\"--max-old-space-size=6144\" npx tsc\n" }, { "path": ".gitignore", "content": "node_modules\nyarn.lock\n" }, { "path": ".npmrc", "content": "package-lock=false\n" }, { "path": "CLAUDE.md", "content": "# type-fest\n\nTypeScript utility types library. Pure type-level programming—no runtime code.\n\n**Read `.github/contributing.md` for complete guidelines.**\n\n## Commands\n\n```bash\nnpm test # MUST pass before committing (runs all below)\nnpm run test:tsc # TypeScript compiler\nnpm run test:tsd # Type tests (tsd)\nnpm run test:xo # Linter\n```\n\n## File Structure\n\n```\nsource/type-name.d.ts → Type definition (.d.ts REQUIRED)\ntest-d/type-name.ts → Tests (tsd)\nindex.d.ts → Export (MUST add, lint enforces)\nreadme.md → API docs (add to category)\nsource/internal/ → Shared helpers (not exported)\n```\n\n## Code Patterns\n\n```ts\n// ✅ CORRECT\nimport type {IsNever} from './is-never.d.ts'; // Include .d.ts\nexport type MyType = ... // Descriptive names (not T/U)\nexport {}; // REQUIRED at end\n\n// ❌ WRONG\nimport type {IsNever} from './is-never'; // Missing .d.ts\nexport type MyType = ...; // Single-letter\n\n/**\nCreates a tuple type of specified length with elements of specified type.\n\nUse-cases:\n- Define fixed-length arrays with specific types\n\n@example\n```\nimport type {TupleOf} from 'type-fest';\ntype RGB = TupleOf<3, number>; //=> [number, number, number]\n```\n\n@category Array\n*/\nexport type TupleOf = ...;\nexport {};\n```\n\nType params: `Value`, `Target`, `Item`, `Length`, `Element`, `Key` (not `T`, `U`, `V`, `K`)\nDocs: No `*` prefix. First line → readme. Include use-cases, examples, `@category`.\n\n## Testing\n\n**ALWAYS test edge cases** (`any`, `never`, `unknown`).\n\n```ts\nexpectType('' as MyType<'foo'>); // Basic\nexpectType('' as MyType); // any/never/unknown\nexpectNotAssignable>({wrong: true}); // Negative\nexpectError>(); // Should error\n```\n\nStudy: `source/tuple-of.d.ts`, `is-equal.d.ts`, `literal-union.d.ts`, `internal/*.d.ts`\n\n## Workflow\n\n1. Research - Study `source/` similar types + online research\n2. Define - `source/type-name.d.ts` with docs\n3. Test - `test-d/type-name.ts` with edge cases\n4. Export - Add to `index.d.ts` + readme.md\n5. Verify - `npm test` must pass\n6. Commit - ``Add `TypeName` type`` or `` `TypeName`: Fix description``\n\n## Critical Rules\n\n1. Import paths MUST include `.d.ts` extension\n2. Files MUST end with `export {};`\n3. Types MUST be exported from `index.d.ts`\n4. Type params MUST use descriptive names (not `T`/`U`)\n5. MUST test `any`, `never`, `unknown` edge cases\n6. First doc line MUST be concise (goes in readme)\n7. Use realistic examples with `//=>` comments\n8. Include `@category` tags\n9. Fix lint issues, don't disable rules\n\n## Type Programming\n\n- Conditionals: `T extends U ? X : Y`\n- Recursion: `type Loop = ... Loop<...> ...`\n- Extract: `infer Item`\n- Distribute: `T extends any ? ... : never`\n- Count via tuple `['length']`\n- Union distribution is tricky—test it\n\n## Philosophy\n\n- Correctness > cleverness\n- Real problems only\n- Docs teach how, not what\n- Edge cases mandatory\n- One concept per PR\n- Descriptive names > brevity\n- No unrelated changes\n\n## Troubleshooting\n\n- Tests fail? Check `.d.ts` imports, `export {};`, edge cases (`any`, `never`, `unknown`)\n- Lint errors? Add to `index.d.ts`, fix issues (don't disable rules)\n" }, { "path": "index.d.ts", "content": "// Basic\nexport type * from './source/primitive.d.ts';\nexport type * from './source/typed-array.d.ts';\nexport type * from './source/basic.d.ts';\nexport type * from './source/json-value.d.ts';\nexport type * from './source/characters.d.ts';\n\n// Utilities\nexport type {KeysOfUnion} from './source/keys-of-union.d.ts';\nexport type {DistributedOmit} from './source/distributed-omit.d.ts';\nexport type {DistributedPick} from './source/distributed-pick.d.ts';\nexport type {EmptyObject, IsEmptyObject} from './source/empty-object.d.ts';\nexport type {IfEmptyObject} from './source/if-empty-object.d.ts';\nexport type {NonEmptyObject} from './source/non-empty-object.d.ts';\nexport type {NonEmptyString} from './source/non-empty-string.d.ts';\nexport type {UnknownRecord} from './source/unknown-record.d.ts';\nexport type {UnknownArray} from './source/unknown-array.d.ts';\nexport type {UnknownSet} from './source/unknown-set.d.ts';\nexport type {UnknownMap} from './source/unknown-map.d.ts';\nexport type {Except, ExceptOptions} from './source/except.d.ts';\nexport type {TaggedUnion} from './source/tagged-union.d.ts';\nexport type {Writable} from './source/writable.d.ts';\nexport type {WritableDeep} from './source/writable-deep.d.ts';\nexport type {Merge} from './source/merge.d.ts';\nexport type {ObjectMerge} from './source/object-merge.d.ts';\nexport type {MergeDeep, MergeDeepOptions} from './source/merge-deep.d.ts';\nexport type {MergeExclusive} from './source/merge-exclusive.d.ts';\nexport type {RequireAtLeastOne} from './source/require-at-least-one.d.ts';\nexport type {RequireExactlyOne} from './source/require-exactly-one.d.ts';\nexport type {RequireAllOrNone} from './source/require-all-or-none.d.ts';\nexport type {RequireOneOrNone} from './source/require-one-or-none.d.ts';\nexport type {SingleKeyObject} from './source/single-key-object.d.ts';\nexport type {OmitIndexSignature} from './source/omit-index-signature.d.ts';\nexport type {PickIndexSignature} from './source/pick-index-signature.d.ts';\nexport type {PartialDeep, PartialDeepOptions} from './source/partial-deep.d.ts';\nexport type {UnwrapPartial} from './source/unwrap-partial.d.ts';\nexport type {RequiredDeep} from './source/required-deep.d.ts';\nexport type {PickDeep} from './source/pick-deep.d.ts';\nexport type {OmitDeep} from './source/omit-deep.d.ts';\nexport type {PartialOnUndefinedDeep, PartialOnUndefinedDeepOptions} from './source/partial-on-undefined-deep.d.ts';\nexport type {UndefinedOnPartialDeep} from './source/undefined-on-partial-deep.d.ts';\nexport type {ReadonlyDeep} from './source/readonly-deep.d.ts';\nexport type {LiteralUnion} from './source/literal-union.d.ts';\nexport type {Promisable} from './source/promisable.d.ts';\nexport type {Arrayable} from './source/arrayable.d.ts';\nexport type {Optional} from './source/optional.d.ts';\nexport type {Opaque, UnwrapOpaque, Tagged, GetTagMetadata, UnwrapTagged} from './source/tagged.d.ts';\nexport type {InvariantOf} from './source/invariant-of.d.ts';\nexport type {SetOptional} from './source/set-optional.d.ts';\nexport type {SetReadonly} from './source/set-readonly.d.ts';\nexport type {SetRequired} from './source/set-required.d.ts';\nexport type {SetRequiredDeep} from './source/set-required-deep.d.ts';\nexport type {SetNonNullable} from './source/set-non-nullable.d.ts';\nexport type {SetNonNullableDeep} from './source/set-non-nullable-deep.d.ts';\nexport type {ValueOf} from './source/value-of.d.ts';\nexport type {AsyncReturnType} from './source/async-return-type.d.ts';\nexport type {ConditionalExcept} from './source/conditional-except.d.ts';\nexport type {ConditionalKeys} from './source/conditional-keys.d.ts';\nexport type {ConditionalPick} from './source/conditional-pick.d.ts';\nexport type {ConditionalPickDeep, ConditionalPickDeepOptions} from './source/conditional-pick-deep.d.ts';\nexport type {UnionToIntersection} from './source/union-to-intersection.d.ts';\nexport type {Stringified} from './source/stringified.d.ts';\nexport type {StringSlice} from './source/string-slice.d.ts';\nexport type {FixedLengthArray} from './source/fixed-length-array.d.ts';\nexport type {MultidimensionalArray} from './source/multidimensional-array.d.ts';\nexport type {MultidimensionalReadonlyArray} from './source/multidimensional-readonly-array.d.ts';\nexport type {IterableElement} from './source/iterable-element.d.ts';\nexport type {Entry} from './source/entry.d.ts';\nexport type {Entries} from './source/entries.d.ts';\nexport type {SetReturnType} from './source/set-return-type.d.ts';\nexport type {SetParameterType} from './source/set-parameter-type.d.ts';\nexport type {Asyncify} from './source/asyncify.d.ts';\nexport type {Simplify} from './source/simplify.d.ts';\nexport type {SimplifyDeep} from './source/simplify-deep.d.ts';\nexport type {Jsonify} from './source/jsonify.d.ts';\nexport type {Jsonifiable} from './source/jsonifiable.d.ts';\nexport type {StructuredCloneable} from './source/structured-cloneable.d.ts';\nexport type {Schema, SchemaOptions} from './source/schema.d.ts';\nexport type {LiteralToPrimitive} from './source/literal-to-primitive.d.ts';\nexport type {LiteralToPrimitiveDeep} from './source/literal-to-primitive-deep.d.ts';\nexport type {\n\tPositiveInfinity,\n\tNegativeInfinity,\n\tFinite,\n\tInteger,\n\tFloat,\n\tNegativeFloat,\n\tNegative,\n\tNonNegative,\n\tNegativeInteger,\n\tNonNegativeInteger,\n\tIsNegative,\n} from './source/numeric.d.ts';\nexport type {GreaterThan} from './source/greater-than.d.ts';\nexport type {GreaterThanOrEqual} from './source/greater-than-or-equal.d.ts';\nexport type {LessThan} from './source/less-than.d.ts';\nexport type {LessThanOrEqual} from './source/less-than-or-equal.d.ts';\nexport type {Sum} from './source/sum.d.ts';\nexport type {Subtract} from './source/subtract.d.ts';\nexport type {KeyAsString} from './source/key-as-string.d.ts';\nexport type {Exact} from './source/exact.d.ts';\nexport type {ReadonlyTuple} from './source/readonly-tuple.d.ts';\nexport type {OverrideProperties} from './source/override-properties.d.ts';\nexport type {OptionalKeysOf} from './source/optional-keys-of.d.ts';\nexport type {IsOptionalKeyOf} from './source/is-optional-key-of.d.ts';\nexport type {HasOptionalKeys} from './source/has-optional-keys.d.ts';\nexport type {RequiredKeysOf} from './source/required-keys-of.d.ts';\nexport type {IsRequiredKeyOf} from './source/is-required-key-of.d.ts';\nexport type {HasRequiredKeys} from './source/has-required-keys.d.ts';\nexport type {ReadonlyKeysOf} from './source/readonly-keys-of.d.ts';\nexport type {IsReadonlyKeyOf} from './source/is-readonly-key-of.d.ts';\nexport type {HasReadonlyKeys} from './source/has-readonly-keys.d.ts';\nexport type {WritableKeysOf} from './source/writable-keys-of.d.ts';\nexport type {IsWritableKeyOf} from './source/is-writable-key-of.d.ts';\nexport type {HasWritableKeys} from './source/has-writable-keys.d.ts';\nexport type {Spread} from './source/spread.d.ts';\nexport type {SplitOnRestElement} from './source/split-on-rest-element.d.ts';\nexport type {ExtractRestElement} from './source/extract-rest-element.d.ts';\nexport type {ExcludeRestElement} from './source/exclude-rest-element.d.ts';\nexport type {IsInteger} from './source/is-integer.d.ts';\nexport type {IsFloat} from './source/is-float.d.ts';\nexport type {TupleToObject} from './source/tuple-to-object.d.ts';\nexport type {TupleToUnion} from './source/tuple-to-union.d.ts';\nexport type {UnionToTuple} from './source/union-to-tuple.d.ts';\nexport type {IntRange} from './source/int-range.d.ts';\nexport type {IntClosedRange} from './source/int-closed-range.d.ts';\nexport type {IsEqual} from './source/is-equal.d.ts';\nexport type {\n\tIsLiteral,\n\tIsStringLiteral,\n\tIsNumericLiteral,\n\tIsBooleanLiteral,\n\tIsSymbolLiteral,\n} from './source/is-literal.d.ts';\nexport type {IsAny} from './source/is-any.d.ts';\nexport type {IfAny} from './source/if-any.d.ts';\nexport type {IsNever} from './source/is-never.d.ts';\nexport type {IfNever} from './source/if-never.d.ts';\nexport type {IsUnknown} from './source/is-unknown.d.ts';\nexport type {IfUnknown} from './source/if-unknown.d.ts';\nexport type {IsTuple, IsTupleOptions} from './source/is-tuple.d.ts';\nexport type {ArrayIndices} from './source/array-indices.d.ts';\nexport type {ArrayValues} from './source/array-values.d.ts';\nexport type {ArraySlice} from './source/array-slice.d.ts';\nexport type {ArraySplice} from './source/array-splice.d.ts';\nexport type {ArrayTail} from './source/array-tail.d.ts';\nexport type {ArrayElement} from './source/array-element.d.ts';\nexport type {ArrayLength} from './source/array-length.d.ts';\nexport type {SetFieldType, SetFieldTypeOptions} from './source/set-field-type.d.ts';\nexport type {Paths, PathsOptions} from './source/paths.d.ts';\nexport type {AllUnionFields} from './source/all-union-fields.d.ts';\nexport type {SharedUnionFields} from './source/shared-union-fields.d.ts';\nexport type {SharedUnionFieldsDeep, SharedUnionFieldsDeepOptions} from './source/shared-union-fields-deep.d.ts';\nexport type {IsNull} from './source/is-null.d.ts';\nexport type {IfNull} from './source/if-null.d.ts';\nexport type {IsUndefined} from './source/is-undefined.d.ts';\nexport type {And} from './source/and.d.ts';\nexport type {AndAll} from './source/and-all.d.ts';\nexport type {Or} from './source/or.d.ts';\nexport type {OrAll} from './source/or-all.d.ts';\nexport type {Xor} from './source/xor.d.ts';\nexport type {AllExtend, AllExtendOptions} from './source/all-extend.d.ts';\nexport type {SomeExtend, SomeExtendOptions} from './source/some-extend.d.ts';\nexport type {NonEmptyTuple} from './source/non-empty-tuple.d.ts';\nexport type {FindGlobalInstanceType, FindGlobalType} from './source/find-global-type.d.ts';\nexport type {If} from './source/if.d.ts';\nexport type {IsUnion} from './source/is-union.d.ts';\nexport type {IsLowercase} from './source/is-lowercase.d.ts';\nexport type {IsUppercase} from './source/is-uppercase.d.ts';\nexport type {IsOptional} from './source/is-optional.d.ts';\nexport type {IsNullable} from './source/is-nullable.d.ts';\nexport type {TupleOf} from './source/tuple-of.d.ts';\nexport type {ExclusifyUnion} from './source/exclusify-union.d.ts';\nexport type {ArrayReverse} from './source/array-reverse.d.ts';\nexport type {UnionMember} from './source/union-member.d.ts';\n\n// Template literal types\nexport type {CamelCase, CamelCaseOptions} from './source/camel-case.d.ts';\nexport type {CamelCasedProperties} from './source/camel-cased-properties.d.ts';\nexport type {CamelCasedPropertiesDeep} from './source/camel-cased-properties-deep.d.ts';\nexport type {KebabCase} from './source/kebab-case.d.ts';\nexport type {KebabCasedProperties} from './source/kebab-cased-properties.d.ts';\nexport type {KebabCasedPropertiesDeep} from './source/kebab-cased-properties-deep.d.ts';\nexport type {PascalCase} from './source/pascal-case.d.ts';\nexport type {PascalCasedProperties} from './source/pascal-cased-properties.d.ts';\nexport type {PascalCasedPropertiesDeep} from './source/pascal-cased-properties-deep.d.ts';\nexport type {SnakeCase} from './source/snake-case.d.ts';\nexport type {SnakeCasedProperties} from './source/snake-cased-properties.d.ts';\nexport type {SnakeCasedPropertiesDeep} from './source/snake-cased-properties-deep.d.ts';\nexport type {ScreamingSnakeCase} from './source/screaming-snake-case.d.ts';\nexport type {DelimiterCase} from './source/delimiter-case.d.ts';\nexport type {DelimiterCasedProperties} from './source/delimiter-cased-properties.d.ts';\nexport type {DelimiterCasedPropertiesDeep} from './source/delimiter-cased-properties-deep.d.ts';\nexport type {Join} from './source/join.d.ts';\nexport type {Split, SplitOptions} from './source/split.d.ts';\nexport type {Words, WordsOptions} from './source/words.d.ts';\nexport type {Trim} from './source/trim.d.ts';\nexport type {Replace, ReplaceOptions} from './source/replace.d.ts';\nexport type {StringRepeat} from './source/string-repeat.d.ts';\nexport type {Includes} from './source/includes.d.ts';\nexport type {Get, GetOptions} from './source/get.d.ts';\nexport type {LastArrayElement} from './source/last-array-element.d.ts';\nexport type {ConditionalSimplify} from './source/conditional-simplify.d.ts';\nexport type {ConditionalSimplifyDeep} from './source/conditional-simplify-deep.d.ts';\nexport type {RemovePrefix, RemovePrefixOptions} from './source/remove-prefix.d.ts';\n\n// Miscellaneous\nexport type {GlobalThis} from './source/global-this.d.ts';\nexport type {PackageJson} from './source/package-json.d.ts';\nexport type {TsConfigJson} from './source/tsconfig-json.d.ts';\n\n// Improved built-in\nexport type {ExtendsStrict} from './source/extends-strict.d.ts';\nexport type {ExtractStrict} from './source/extract-strict.d.ts';\nexport type {ExcludeStrict} from './source/exclude-strict.d.ts';\nexport type {ExcludeExactly} from './source/exclude-exactly.d.ts';\n\nexport {};\n" }, { "path": "license-cc0", "content": "Creative Commons Legal Code\n\nCC0 1.0 Universal\n\n CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES NOT PROVIDE\n LEGAL SERVICES. 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Should any part of the License for any\nreason be judged legally invalid or ineffective under applicable law, such\npartial invalidity or ineffectiveness shall not invalidate the remainder\nof the License, and in such case Affirmer hereby affirms that he or she\nwill not (i) exercise any of his or her remaining Copyright and Related\nRights in the Work or (ii) assert any associated claims and causes of\naction with respect to the Work, in either case contrary to Affirmer's\nexpress Statement of Purpose.\n\n4. Limitations and Disclaimers.\n\n a. No trademark or patent rights held by Affirmer are waived, abandoned,\n surrendered, licensed or otherwise affected by this document.\n b. 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Affirmer understands and acknowledges that Creative Commons is not a\n party to this document and has no duty or obligation with respect to\n this CC0 or use of the Work.\n" }, { "path": "license-mit", "content": "MIT License\n\nCopyright (c) Sindre Sorhus (https://sindresorhus.com)\n\nPermission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the \"Software\"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:\n\nThe above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\n" }, { "path": "lint-processors/fixtures/eslint.config.js", "content": "import tseslint from 'typescript-eslint';\nimport {defineConfig} from 'eslint/config';\nimport {jsdocCodeblocksProcessor} from '../jsdoc-codeblocks.js';\n\nconst errorEndingAtFirstColumnRule = {\n\tcreate(context) {\n\t\treturn {\n\t\t\t'TSTypeAliasDeclaration Literal'(node) {\n\t\t\t\tif (node.value !== 'error_ending_at_first_column') {\n\t\t\t\t\treturn;\n\t\t\t\t}\n\n\t\t\t\tcontext.report({\n\t\t\t\t\tloc: {\n\t\t\t\t\t\tstart: {\n\t\t\t\t\t\t\tline: node.loc.start.line,\n\t\t\t\t\t\t\tcolumn: 0,\n\t\t\t\t\t\t},\n\t\t\t\t\t\tend: {\n\t\t\t\t\t\t\tline: node.loc.start.line + 1,\n\t\t\t\t\t\t\tcolumn: 0,\n\t\t\t\t\t\t},\n\t\t\t\t\t},\n\t\t\t\t\tmessage: 'Error ending at first column',\n\t\t\t\t});\n\t\t\t},\n\t\t};\n\t},\n};\n\nconst config = defineConfig(\n\ttseslint.configs.recommended,\n\ttseslint.configs.stylistic,\n\t{\n\t\trules: {\n\t\t\t'@typescript-eslint/no-unused-vars': 'off',\n\t\t\t'@typescript-eslint/consistent-type-definitions': [\n\t\t\t\t'error',\n\t\t\t\t'type',\n\t\t\t],\n\t\t\t'test/error-ending-at-first-column': 'error',\n\t\t},\n\t},\n\t{\n\t\tplugins: {\n\t\t\ttest: {\n\t\t\t\tprocessors: {\n\t\t\t\t\t'jsdoc-codeblocks': jsdocCodeblocksProcessor,\n\t\t\t\t},\n\t\t\t\trules: {\n\t\t\t\t\t'error-ending-at-first-column': errorEndingAtFirstColumnRule,\n\t\t\t\t},\n\t\t\t},\n\t\t},\n\t},\n\t{\n\t\tfiles: ['**/*.d.ts'],\n\t\tprocessor: 'test/jsdoc-codeblocks',\n\t},\n);\n\nexport default config;\n" }, { "path": "lint-processors/jsdoc-codeblocks.js", "content": "// @ts-check\nimport tsParser from '@typescript-eslint/parser';\n\n/**\n@import {Linter} from 'eslint';\n*/\n\nconst CODEBLOCK_REGEX = /(?(?^[ \\t]*)```(?:ts|typescript)?\\n)(?[\\s\\S]*?)\\n\\s*```/gm;\n/**\n@typedef {{lineOffset: number, characterOffset: number, indent: string, unindentedText: string}} CodeblockData\n@type {Map}\n*/\nconst codeblockDataPerFile = new Map();\n\n/**\n@param {string} text\n@param {number} index\n@param {string} indent\n@returns {number}\n*/\nfunction indentsUptoIndex(text, index, indent) {\n\tlet i = 0;\n\tlet indents = 0;\n\n\tfor (const line of text.split('\\n')) {\n\t\tif (i > index) {\n\t\t\tbreak;\n\t\t}\n\n\t\tif (line === '') {\n\t\t\ti += 1; // +1 for the newline\n\t\t\tcontinue;\n\t\t}\n\n\t\ti += line.length + 1; // +1 for the newline\n\t\ti -= indent.length; // Because `text` is unindented but `index` corresponds to dedented text\n\t\tindents += indent.length;\n\t}\n\n\treturn indents;\n}\n\nexport const jsdocCodeblocksProcessor = {\n\tsupportsAutofix: true,\n\n\t/**\n\t@param {string} text\n\t@param {string} filename\n\t@returns {(string | Linter.ProcessorFile)[]}\n\t*/\n\tpreprocess(text, filename) {\n\t\tconst ast = tsParser.parse(text);\n\n\t\tconst jsdocComments = ast.comments.filter(\n\t\t\tcomment => comment.type === 'Block' && comment.value.startsWith('*'),\n\t\t);\n\n\t\t/** @type {(string | Linter.ProcessorFile)[]} */\n\t\tconst files = [text]; // First entry is for the entire file\n\t\t/** @type {CodeblockData[]} */\n\t\tconst allCodeblocksData = [];\n\n\t\t// Loop over all JSDoc comments in the file\n\t\tfor (const comment of jsdocComments) {\n\t\t\t// Loop over all codeblocks in the JSDoc comment\n\t\t\tfor (const match of comment.value.matchAll(CODEBLOCK_REGEX)) {\n\t\t\t\tconst {code, openingFence, indent} = match.groups ?? {};\n\n\t\t\t\t// Skip empty code blocks\n\t\t\t\tif (!code || !openingFence || indent === undefined) {\n\t\t\t\t\tcontinue;\n\t\t\t\t}\n\n\t\t\t\tconst codeLines = code.split('\\n');\n\t\t\t\tconst indentSize = indent.length;\n\n\t\t\t\t// Skip comments that are not consistently indented\n\t\t\t\tif (!codeLines.every(line => line === '' || line.startsWith(indent))) {\n\t\t\t\t\tcontinue;\n\t\t\t\t}\n\n\t\t\t\tconst dedentedCode = codeLines\n\t\t\t\t\t.map(line => line.slice(indentSize))\n\t\t\t\t\t.join('\\n');\n\n\t\t\t\tfiles.push({\n\t\t\t\t\ttext: dedentedCode,\n\t\t\t\t\tfilename: `${files.length}.ts`, // Final filename example: `/path/to/type-fest/source/and.d.ts/1_1.ts`\n\t\t\t\t});\n\n\t\t\t\tconst linesBeforeMatch = comment.value.slice(0, match.index).split('\\n').length - 1;\n\t\t\t\tallCodeblocksData.push({\n\t\t\t\t\tlineOffset: comment.loc.start.line + linesBeforeMatch,\n\t\t\t\t\tcharacterOffset: comment.range[0] + match.index + openingFence.length + 2, // +2 because `comment.value` doesn't include the starting `/*`\n\t\t\t\t\tindent,\n\t\t\t\t\tunindentedText: code,\n\t\t\t\t});\n\t\t\t}\n\t\t}\n\n\t\tcodeblockDataPerFile.set(filename, allCodeblocksData);\n\n\t\treturn files;\n\t},\n\n\t/**\n\t@param {import('eslint').Linter.LintMessage[][]} messages\n\t@param {string} filename\n\t@returns {import('eslint').Linter.LintMessage[]}\n\t*/\n\tpostprocess(messages, filename) {\n\t\tconst codeblocks = codeblockDataPerFile.get(filename) || [];\n\t\tcodeblockDataPerFile.delete(filename);\n\n\t\tconst normalizedMessages = [...(messages[0] ?? [])]; // First entry contains errors for the entire file, and it doesn't need any adjustments\n\n\t\tfor (const [index, codeblockMessages] of messages.slice(1).entries()) {\n\t\t\tconst codeblockData = codeblocks[index];\n\n\t\t\tif (!codeblockData) {\n\t\t\t\t// This should ideally never happen\n\t\t\t\tcontinue;\n\t\t\t}\n\n\t\t\tconst {lineOffset, characterOffset, indent, unindentedText} = codeblockData;\n\n\t\t\tfor (const message of codeblockMessages) {\n\t\t\t\tmessage.line += lineOffset;\n\t\t\t\tmessage.column += indent.length;\n\n\t\t\t\tif (typeof message.endColumn === 'number' && message.endColumn > 1) {\n\t\t\t\t\t// An `endColumn` of `1` indicates the error actually ended on the previous line since it's exclusive.\n\t\t\t\t\t// So, adding `indent.length` in this case would incorrectly move the error marker into the indentation.\n\t\t\t\t\t// Therefore, the indentation length is only added when `endColumn` is greater than `1`.\n\t\t\t\t\tmessage.endColumn += indent.length;\n\t\t\t\t}\n\n\t\t\t\tif (typeof message.endLine === 'number') {\n\t\t\t\t\tmessage.endLine += lineOffset;\n\t\t\t\t}\n\n\t\t\t\tif (message.fix) {\n\t\t\t\t\tmessage.fix.text = message.fix.text.split('\\n').join(`\\n${indent}`);\n\n\t\t\t\t\tconst indentsBeforeFixStart = indentsUptoIndex(unindentedText, message.fix.range[0], indent);\n\t\t\t\t\tconst indentsBeforeFixEnd = indentsUptoIndex(unindentedText, message.fix.range[1] - 1, indent); // -1 because range end is exclusive\n\n\t\t\t\t\tmessage.fix.range = [\n\t\t\t\t\t\tmessage.fix.range[0] + characterOffset + indentsBeforeFixStart,\n\t\t\t\t\t\tmessage.fix.range[1] + characterOffset + indentsBeforeFixEnd,\n\t\t\t\t\t];\n\t\t\t\t}\n\n\t\t\t\tfor (const {fix} of (message.suggestions ?? [])) {\n\t\t\t\t\tfix.text = fix.text.split('\\n').join(`\\n${indent}`);\n\n\t\t\t\t\tconst indentsBeforeFixStart = indentsUptoIndex(unindentedText, fix.range[0], indent);\n\t\t\t\t\tconst indentsBeforeFixEnd = indentsUptoIndex(unindentedText, fix.range[1] - 1, indent); // -1 because range end is exclusive\n\n\t\t\t\t\tfix.range = [\n\t\t\t\t\t\tfix.range[0] + characterOffset + indentsBeforeFixStart,\n\t\t\t\t\t\tfix.range[1] + characterOffset + indentsBeforeFixEnd,\n\t\t\t\t\t];\n\t\t\t\t}\n\n\t\t\t\tnormalizedMessages.push(message);\n\t\t\t}\n\t\t}\n\n\t\treturn normalizedMessages;\n\t},\n};\n" }, { "path": "lint-processors/jsdoc-codeblocks.test.js", "content": "import {describe, test} from 'node:test';\nimport fs from 'node:fs/promises';\nimport path from 'node:path';\nimport {ESLint} from 'eslint';\nimport {code1, code2, dedenter, errorAt, exportType, exportTypeAndOption, fence, jsdoc} from '../lint-rules/test-utils.js';\n\nconst root = path.join(import.meta.dirname, 'fixtures');\n\ntry {\n\tawait fs.access(path.join(root, 'eslint.config.js'));\n} catch {\n\tthrow new Error('\\'eslint.config.js\\' is missing in \\'lint-processors/fixtures\\' directory.');\n}\n\nconst valid = [\n\t{\n\t\tname: 'No JSDoc',\n\t\tcode: exportTypeAndOption(''),\n\t},\n\t{\n\t\tname: 'JSDoc without code block',\n\t\tcode: exportType(jsdoc('No codeblock here')),\n\t},\n\t{\n\t\tname: 'Valid code block',\n\t\tcode: exportTypeAndOption(jsdoc(fence(code1))),\n\t},\n\t{\n\t\tname: 'With text before and after',\n\t\tcode: exportTypeAndOption(jsdoc('Some description.', fence(code1), '@category Test')),\n\t},\n\t{\n\t\tname: 'With line breaks before and after',\n\t\tcode: exportTypeAndOption(\n\t\t\tjsdoc('Some description.\\n', 'Note: Some note.\\n', fence(code1, 'ts'), '\\n@category Test'),\n\t\t),\n\t},\n\t{\n\t\tname: 'With @example tag',\n\t\tcode: exportTypeAndOption(jsdoc('@example', fence(code1))),\n\t},\n\t{\n\t\tname: 'With ts language specifier',\n\t\tcode: exportTypeAndOption(jsdoc(fence(code1, 'ts'))),\n\t},\n\t{\n\t\tname: 'With typescript language specifier',\n\t\tcode: exportTypeAndOption(jsdoc(fence(code1, 'typescript'))),\n\t},\n\t{\n\t\tname: 'Multiple code blocks',\n\t\tcode: exportTypeAndOption(\n\t\t\tjsdoc('@example', fence(code1, 'ts'), '\\nSome text in between.\\n', '@example', fence(code2)),\n\t\t),\n\t},\n\t{\n\t\tname: 'Multiple exports and multiple properties',\n\t\tcode: exportTypeAndOption(jsdoc(fence(code1)), jsdoc(fence(code2))),\n\t},\n\t{\n\t\tname: 'Indented code blocks',\n\t\tcode: exportTypeAndOption(jsdoc(\n\t\t\t'Note:',\n\t\t\tdedenter`\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {Subtract} from 'type-fest';\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {Sum} from 'type-fest';\n\t\t\t\t\ttype A = Sum<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t`,\n\t\t)),\n\t},\n\t{\n\t\tname: 'Ignore codeblocks with inconsistent indentation',\n\t\tcode: exportTypeAndOption(jsdoc(\n\t\t\t'Some description.',\n\t\t\tdedenter`\n\t\t\tNote:\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: string = '1';\n\n\t\t\tconst bar: number = 1;\n\t\t\t\t\\`\\`\\`\n\t\t\t`,\n\t\t)),\n\t},\n];\n\nconst invalid = [\n\t{\n\t\tname: 'With text before and after',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: Array = [];\n\t\t\t\\`\\`\\`\n\t\t\t@category Test\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: Array = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: string[] = [];\n\t\t\t\\`\\`\\`\n\t\t\t@category Test\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: string[] = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 4,\n\t\t\t\ttextBeforeStart: 'const foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 14,\n\t\t\t\ttextBeforeStart: '\\tconst foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'With line breaks before and after',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\n\t\t\tNote: Some note.\n\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: number = 1;\n\t\t\t\\`\\`\\`\n\n\t\t\t@category Test\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\n\t\t\t\tNote: Some note.\n\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: number = 1;\n\t\t\t\t\\`\\`\\`\n\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\n\t\t\tNote: Some note.\n\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo = 1;\n\t\t\t\\`\\`\\`\n\n\t\t\t@category Test\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\n\t\t\t\tNote: Some note.\n\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = 1;\n\t\t\t\t\\`\\`\\`\n\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-inferrable-types',\n\t\t\t\tline: 7,\n\t\t\t\ttextBeforeStart: 'const ',\n\t\t\t\ttarget: 'foo: number = 1',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-inferrable-types',\n\t\t\t\tline: 21,\n\t\t\t\ttextBeforeStart: '\\tconst ',\n\t\t\t\ttarget: 'foo: number = 1',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'With @example tag',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\tinterface Foo {\n\t\t\t\ta: string;\n\t\t\t\tb: number;\n\t\t\t}\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tinterface Foo {\n\t\t\t\t\ta: string;\n\t\t\t\t\tb: number;\n\t\t\t\t}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Foo = {\n\t\t\t\ta: string;\n\t\t\t\tb: number;\n\t\t\t}\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = {\n\t\t\t\t\ta: string;\n\t\t\t\t\tb: number;\n\t\t\t\t}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-type-definitions',\n\t\t\t\tline: 4,\n\t\t\t\ttextBeforeStart: 'interface ',\n\t\t\t\ttarget: 'Foo',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-type-definitions',\n\t\t\t\tline: 16,\n\t\t\t\ttextBeforeStart: '\\tinterface ',\n\t\t\t\ttarget: 'Foo',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'With language specifiers',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: Array = [];\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: Array = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: string[] = [];\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: string[] = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 3,\n\t\t\t\ttextBeforeStart: 'const foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 11,\n\t\t\t\ttextBeforeStart: '\\tconst foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'With typescript language specifiers',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`typescript\n\t\t\tconst foo: Array = [];\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`typescript\n\t\t\t\tconst foo: Array = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`typescript\n\t\t\tconst foo: string[] = [];\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`typescript\n\t\t\t\tconst foo: string[] = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 3,\n\t\t\t\ttextBeforeStart: 'const foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 11,\n\t\t\t\ttextBeforeStart: '\\tconst foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Multiple code blocks',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: Array = [];\n\t\t\t\\`\\`\\`\n\n\t\t\tSome text in between.\n\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\tconst bar: number = 1;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: Array = [];\n\t\t\t\t\\`\\`\\`\n\n\t\t\t\tSome text in between.\n\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst bar: number = 1;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: string[] = [];\n\t\t\t\\`\\`\\`\n\n\t\t\tSome text in between.\n\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\tconst bar = 1;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: string[] = [];\n\t\t\t\t\\`\\`\\`\n\n\t\t\t\tSome text in between.\n\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst bar = 1;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 4,\n\t\t\t\ttextBeforeStart: 'const foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-inferrable-types',\n\t\t\t\tline: 11,\n\t\t\t\ttextBeforeStart: 'const ',\n\t\t\t\ttarget: 'bar: number = 1',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 20,\n\t\t\t\ttextBeforeStart: '\\tconst foo: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-inferrable-types',\n\t\t\t\tline: 27,\n\t\t\t\ttextBeforeStart: '\\tconst ',\n\t\t\t\ttarget: 'bar: number = 1',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Multiple exports and multiple properties',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tfunction foo(example: {(): number}): number {\n\t\t\t\treturn example();\n\t\t\t}\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Foo = {\n\t\t\t\t[key: string]: unknown;\n\t\t\t};\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T1 = string;\n\n\t\t\texport type T0Options = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tfunction foo(example: {(): number}): number {\n\t\t\t\t\treturn example();\n\t\t\t\t}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = {\n\t\t\t\t\t[key: string]: unknown;\n\t\t\t\t};\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp1: string;\n\t\t\t};\n\n\t\t\texport type T1Options = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: Map = new Map();\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tfunction foo(example: () => number): number {\n\t\t\t\treturn example();\n\t\t\t}\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Foo = Record;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T1 = string;\n\n\t\t\texport type T0Options = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tfunction foo(example: () => number): number {\n\t\t\t\t\treturn example();\n\t\t\t\t}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = Record;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp1: string;\n\t\t\t};\n\n\t\t\texport type T1Options = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = new Map();\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 3,\n\t\t\t\ttextBeforeStart: 'function foo(example: {',\n\t\t\t\ttarget: '(): number',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 12,\n\t\t\t\ttextBeforeStart: 'type Foo = ',\n\t\t\t\tendLine: 14,\n\t\t\t\ttextBeforeEnd: '}',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 22,\n\t\t\t\ttextBeforeStart: '\\tfunction foo(example: {',\n\t\t\t\ttarget: '(): number',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 31,\n\t\t\t\ttextBeforeStart: '\\ttype Foo = ',\n\t\t\t\tendLine: 33,\n\t\t\t\ttextBeforeEnd: '\\t}',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-generic-constructors',\n\t\t\t\tline: 42,\n\t\t\t\ttextBeforeStart: '\\tconst ',\n\t\t\t\ttarget: 'foo: Map = new Map()',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Indented code blocks',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tNote:\n\t\t\t1. First point\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = {\n\t\t\t\t\t[x: string]: unknown;\n\t\t\t\t};\n\t\t\t\t\\`\\`\\`\n\t\t\t2. Second point\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Bar = {\n\t\t\t\t\t(arg: string): number;\n\t\t\t\t};\n\t\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tNote:\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype Foo = {\n\t\t\t\t\t\t[x: string]: unknown;\n\t\t\t\t\t};\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype Bar = {\n\t\t\t\t\t\t(arg: string): number;\n\t\t\t\t\t};\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\tNote:\n\t\t\t1. First point\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = Record;\n\t\t\t\t\\`\\`\\`\n\t\t\t2. Second point\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Bar = (arg: string) => number;\n\t\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tNote:\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype Foo = Record;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype Bar = (arg: string) => number;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 5,\n\t\t\t\ttextBeforeStart: '\\ttype Foo = ',\n\t\t\t\tendLine: 7,\n\t\t\t\ttextBeforeEnd: '\\t}',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 12,\n\t\t\t\ttextBeforeStart: '\\t\\t',\n\t\t\t\ttarget: '(arg: string): number;',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 23,\n\t\t\t\ttextBeforeStart: '\\t\\ttype Foo = ',\n\t\t\t\tendLine: 25,\n\t\t\t\ttextBeforeEnd: '\\t\\t}',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 30,\n\t\t\t\ttextBeforeStart: '\\t\\t\\t',\n\t\t\t\ttarget: '(arg: string): number;',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Error and fix starting at the first character of the codeblock',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\t\\`\\`\\`ts\n\t\t\tvar foo = 1;\n\t\t\tfoo = 2;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tvar foo = 1;\n\t\t\t\tfoo = 2;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\t\\`\\`\\`ts\n\t\t\tlet foo = 1;\n\t\t\tfoo = 2;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tlet foo = 1;\n\t\t\t\tfoo = 2;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: 'no-var',\n\t\t\t\tline: 4,\n\t\t\t\ttextBeforeStart: '',\n\t\t\t\ttarget: 'var foo = 1;',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: 'no-var',\n\t\t\t\tline: 14,\n\t\t\t\ttextBeforeStart: '\\t',\n\t\t\t\ttarget: 'var foo = 1;',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Error and fix in the middle of the codeblock',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: string[] = [];\n\n\t\t\tconst bar: Array = [];\n\n\t\t\tconst baz: boolean[] = [];\n\t\t\t\\`\\`\\`\n\t\t\tSome text after.\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: string[] = [];\n\n\t\t\t\tconst bar: Array = [];\n\n\t\t\t\tconst baz: boolean[] = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\tSome text after.\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: string[] = [];\n\n\t\t\tconst bar: number[] = [];\n\n\t\t\tconst baz: boolean[] = [];\n\t\t\t\\`\\`\\`\n\t\t\tSome text after.\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: string[] = [];\n\n\t\t\t\tconst bar: number[] = [];\n\n\t\t\t\tconst baz: boolean[] = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\tSome text after.\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 5,\n\t\t\t\ttextBeforeStart: 'const bar: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 18,\n\t\t\t\ttextBeforeStart: '\\tconst bar: ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Error and fix ending at the last character of the codeblock',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Foo = {a: string}\n\t\t\ttype Bar = {[K: string]: Foo}\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = {a: string}\n\t\t\t\ttype Bar = {[K: string]: Foo}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Foo = {a: string}\n\t\t\ttype Bar = Record\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = {a: string}\n\t\t\t\ttype Bar = Record\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 7,\n\t\t\t\ttextBeforeStart: 'type Bar = ',\n\t\t\t\ttarget: '{[K: string]: Foo}',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 19,\n\t\t\t\ttextBeforeStart: '\\ttype Bar = ',\n\t\t\t\ttarget: '{[K: string]: Foo}',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Error spanning multiple lines',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\timport type {PickIndexSignature} from 'type-fest';\n\n\t\t\ttype Foo = {\n\t\t\t\t[key: string]: unknown;\n\t\t\t};\n\n\t\t\ttype Test = PickIndexSignature;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\timport type {PickIndexSignature} from 'type-fest';\n\n\t\t\t\ttype Foo = {\n\t\t\t\t\t[key: string]: unknown;\n\t\t\t\t};\n\n\t\t\t\ttype Test = PickIndexSignature;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\timport type {PickIndexSignature} from 'type-fest';\n\n\t\t\ttype Foo = Record;\n\n\t\t\ttype Test = PickIndexSignature;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\timport type {PickIndexSignature} from 'type-fest';\n\n\t\t\t\ttype Foo = Record;\n\n\t\t\t\ttype Test = PickIndexSignature;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 5,\n\t\t\t\ttextBeforeStart: 'type Foo = ',\n\t\t\t\tendLine: 7,\n\t\t\t\ttextBeforeEnd: '}',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-indexed-object-style',\n\t\t\t\tline: 19,\n\t\t\t\ttextBeforeStart: '\\ttype Foo = ',\n\t\t\t\tendLine: 21,\n\t\t\t\ttextBeforeEnd: '\\t}',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Multiline fix',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\tSome more description.\n\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Test = {(\n\t\t\t\tfoo: string,\n\t\t\t\tbar: number\n\t\t\t): void};\n\t\t\t\\`\\`\\`\n\t\t\t@category Test\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\tSome more description.\n\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = {(\n\t\t\t\t\tfoo: string,\n\t\t\t\t\tbar: number\n\t\t\t\t): void};\n\t\t\t\t\\`\\`\\`\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\tSome more description.\n\n\t\t\t@example\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Test = (\n\t\t\t\tfoo: string,\n\t\t\t\tbar: number\n\t\t\t) => void;\n\t\t\t\\`\\`\\`\n\t\t\t@category Test\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\tSome more description.\n\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = (\n\t\t\t\t\tfoo: string,\n\t\t\t\t\tbar: number\n\t\t\t\t) => void;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 7,\n\t\t\t\ttextBeforeStart: 'type Test = {',\n\t\t\t\tendLine: 10,\n\t\t\t\ttextBeforeEnd: '): void',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 23,\n\t\t\t\ttextBeforeStart: '\\ttype Test = {',\n\t\t\t\tendLine: 26,\n\t\t\t\ttextBeforeEnd: '\\t): void',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Multiple errors',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t@example\n\t\t\t\\`\\`\\`typescript\n\t\t\tconst foo: number = 1\n\n\t\t\tconst bar: Map = new Map()\n\n\t\t\tinterface Baz {\n\t\t\t\t(x: string): unknown\n\t\t\t}\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`typescript\n\t\t\t\tconst foo: number = 1\n\n\t\t\t\tconst bar: Map = new Map()\n\n\t\t\t\tinterface Baz {\n\t\t\t\t\t(x: string): unknown\n\t\t\t\t}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t@example\n\t\t\t\\`\\`\\`typescript\n\t\t\tconst foo = 1\n\n\t\t\tconst bar = new Map()\n\n\t\t\ttype Baz = (x: string) => unknown\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`typescript\n\t\t\t\tconst foo = 1\n\n\t\t\t\tconst bar = new Map()\n\n\t\t\t\ttype Baz = (x: string) => unknown\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-inferrable-types',\n\t\t\t\tline: 4,\n\t\t\t\ttextBeforeStart: 'const ',\n\t\t\t\ttarget: 'foo: number = 1',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-generic-constructors',\n\t\t\t\tline: 6,\n\t\t\t\ttextBeforeStart: 'const ',\n\t\t\t\ttarget: 'bar: Map = new Map()',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-type-definitions',\n\t\t\t\tline: 8,\n\t\t\t\ttextBeforeStart: 'interface ',\n\t\t\t\ttarget: 'Baz',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 9,\n\t\t\t\ttextBeforeStart: '\\t',\n\t\t\t\ttarget: '(x: string): unknown',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-inferrable-types',\n\t\t\t\tline: 19,\n\t\t\t\ttextBeforeStart: '\\tconst ',\n\t\t\t\ttarget: 'foo: number = 1',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-generic-constructors',\n\t\t\t\tline: 21,\n\t\t\t\ttextBeforeStart: '\\tconst ',\n\t\t\t\ttarget: 'bar: Map = new Map()',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/consistent-type-definitions',\n\t\t\t\tline: 23,\n\t\t\t\ttextBeforeStart: '\\tinterface ',\n\t\t\t\ttarget: 'Baz',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 24,\n\t\t\t\ttextBeforeStart: '\\t\\t',\n\t\t\t\ttarget: '(x: string): unknown',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Overlapping errors',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: Array> = [];\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: Array> = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\tconst foo: string[][] = [];\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo: string[][] = [];\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 3,\n\t\t\t\ttextBeforeStart: 'const foo: ',\n\t\t\t\ttarget: 'Array>',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 3,\n\t\t\t\ttextBeforeStart: 'const foo: Array<',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 11,\n\t\t\t\ttextBeforeStart: '\\tconst foo: ',\n\t\t\t\ttarget: 'Array>',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 11,\n\t\t\t\ttextBeforeStart: '\\tconst foo: Array<',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Error reporting location different from fix location',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Foo = {\n\t\t\t\t(): void;\n\t\t\t};\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = {\n\t\t\t\t\t(): void;\n\t\t\t\t};\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\ttype Foo = () => void;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = () => void;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 4,\n\t\t\t\ttextBeforeStart: '\\t',\n\t\t\t\ttarget: '(): void;',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/prefer-function-type',\n\t\t\t\tline: 14,\n\t\t\t\ttextBeforeStart: '\\t\\t',\n\t\t\t\ttarget: '(): void;',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Non fixable error',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\t@example\n\t\t\t\\`\\`\\`\n\t\t\ttype Foo = {};\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`\n\t\t\t\ttype Foo = {};\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: undefined,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-empty-object-type',\n\t\t\t\tline: 5,\n\t\t\t\ttextBeforeStart: 'type Foo = ',\n\t\t\t\ttarget: '{}',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-empty-object-type',\n\t\t\t\tline: 15,\n\t\t\t\ttextBeforeStart: '\\ttype Foo = ',\n\t\t\t\ttarget: '{}',\n\t\t\t}),\n\t\t],\n\t},\n\n\t{\n\t\tname: 'Error outside JSDoc',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\t\\`\\`\\`\n\t\t\ttype Foo = string;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = Array;\n\n\t\t\ttype Foo = String;\n\t\t`,\n\t\toutput: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\t\t\t\\`\\`\\`\n\t\t\ttype Foo = string;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string[];\n\n\t\t\ttype Foo = string;\n\t\t`,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/array-type',\n\t\t\t\tline: 7,\n\t\t\t\ttextBeforeStart: 'export type T0 = ',\n\t\t\t\ttarget: 'Array',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\truleId: '@typescript-eslint/no-wrapper-object-types',\n\t\t\t\tline: 9,\n\t\t\t\ttextBeforeStart: 'type Foo = ',\n\t\t\t\ttarget: 'String',\n\t\t\t}),\n\t\t],\n\t},\n\t{\n\t\tname: 'Error ending at first column',\n\t\tcode: dedenter`\n\t\t\t/**\n\t\t\tSome description.\n\n\t\t\tNote:\n\t\t\t @example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = 'error_ending_at_first_column'\n\t\t\t\ttype Bar = number\n\t\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\n\t\t\texport type TOptions = {\n\t\t\t\t/**\n\t\t\t\tSome description.\n\n\t\t\t\tNote:\n\t\t\t\t\t@example\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype Foo = 'error_ending_at_first_column'\n\t\t\t\t\ttype Bar = number\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\tp0: string;\n\t\t\t};\n\t\t`,\n\t\toutput: undefined,\n\t\terrors: [\n\t\t\terrorAt({\n\t\t\t\tline: 7,\n\t\t\t\ttextBeforeStart: '\\t',\n\t\t\t\tendLine: 8,\n\t\t\t\ttextBeforeEnd: '',\n\t\t\t}),\n\t\t\terrorAt({\n\t\t\t\tline: 20,\n\t\t\t\ttextBeforeStart: '\\t\\t',\n\t\t\t\tendLine: 21,\n\t\t\t\ttextBeforeEnd: '',\n\t\t\t}),\n\t\t],\n\t},\n];\n\ndescribe('jsdoc-codeblocks processor', {concurrency: true}, () => {\n\tconst eslint = new ESLint({cwd: root});\n\tconst eslintFixed = new ESLint({cwd: root, fix: true});\n\n\tconst testCases = [\n\t\t...valid.map(testCase => ({...testCase, type: 'valid'})),\n\t\t...invalid.map(testCase => ({...testCase, type: 'invalid'})),\n\t];\n\n\tfor (const {type, name, code, output, errors = []} of testCases) {\n\t\ttest(`${type} - ${name}`, async t => {\n\t\t\tconst fileName = `test-${type}-${name.replaceAll(/\\s+/g, '-')}.d.ts`;\n\t\t\tconst filePath = path.join(root, fileName);\n\t\t\tawait fs.writeFile(filePath, code);\n\t\t\tt.after(async () => {\n\t\t\t\tawait fs.unlink(filePath);\n\t\t\t});\n\n\t\t\tconst results = await eslint.lintFiles([fileName]);\n\t\t\tt.assert.strictEqual(results[0].messages.length, errors.length);\n\n\t\t\tif (type === 'invalid') {\n\t\t\t\t// Manual loop because `assert.partialDeepStrictEqual` isn't available in Node 20\n\t\t\t\tfor (const [index, expected] of errors.entries()) {\n\t\t\t\t\tconst actual = results[0].messages[index];\n\t\t\t\t\tconst actualSubset = Object.fromEntries(Object.keys(expected).map(key => [key, actual[key]]));\n\n\t\t\t\t\tt.assert.deepStrictEqual(actualSubset, expected);\n\t\t\t\t}\n\n\t\t\t\tconst resultsFixed = await eslintFixed.lintFiles([fileName]);\n\t\t\t\tt.assert.strictEqual(resultsFixed[0].output, output);\n\t\t\t}\n\t\t});\n\t}\n});\n" }, { "path": "lint-rules/import-path.js", "content": "import path from 'node:path';\n\nexport const importPathRule = /** @type {const} */ ({\n\tmeta: {\n\t\ttype: 'problem',\n\t\tdocs: {\n\t\t\tdescription: 'Enforces import paths to end with a \\'.d.ts\\' extension.',\n\t\t},\n\t\tfixable: 'code',\n\t\tmessages: {\n\t\t\tincorrectImportPath:\n 'Import path \\'{{importPath}}\\' must end with a \\'.d.ts\\' extension. Use \\'{{fixedImportPath}}\\' instead.',\n\t\t},\n\t\tschema: [],\n\t},\n\tdefaultOptions: [],\n\tcreate(context) {\n\t\treturn {\n\t\t\t'ImportDeclaration, ExportNamedDeclaration, ExportAllDeclaration'(node) {\n\t\t\t\t// Exit if not a re-export\n\t\t\t\tif (!node.source) {\n\t\t\t\t\treturn;\n\t\t\t\t}\n\n\t\t\t\tconst importPath = node.source.value;\n\n\t\t\t\t// Skip if not relative path\n\t\t\t\tif (!(importPath.startsWith('./') || importPath.startsWith('../'))) {\n\t\t\t\t\treturn;\n\t\t\t\t}\n\n\t\t\t\tconst filename = path.basename(importPath);\n\t\t\t\tconst firstDotIndex = filename.indexOf('.');\n\t\t\t\tconst extension = firstDotIndex === -1 ? '' : filename.slice(firstDotIndex);\n\n\t\t\t\t// Skip if the import path already ends with `.d.ts`\n\t\t\t\tif (extension === '.d.ts') {\n\t\t\t\t\treturn;\n\t\t\t\t}\n\n\t\t\t\tconst importPathWithoutExtension = extension.length > 0\n\t\t\t\t\t? importPath.slice(0, -extension.length)\n\t\t\t\t\t: importPath;\n\t\t\t\tconst fixedImportPath = `${importPathWithoutExtension}.d.ts`;\n\n\t\t\t\tcontext.report({\n\t\t\t\t\tnode: node.source,\n\t\t\t\t\tmessageId: 'incorrectImportPath',\n\t\t\t\t\tfix(fixer) {\n\t\t\t\t\t\treturn fixer.replaceText(node.source, `'${fixedImportPath}'`);\n\t\t\t\t\t},\n\t\t\t\t\tdata: {importPath, fixedImportPath},\n\t\t\t\t});\n\t\t\t},\n\t\t};\n\t},\n});\n" }, { "path": "lint-rules/import-path.test.js", "content": "import {createRuleTester} from './test-utils.js';\nimport {importPathRule} from './import-path.js';\n\nconst ruleTester = createRuleTester();\n\nconst invalidImport = (code, output) => ({\n\tcode,\n\terrors: [{messageId: 'incorrectImportPath'}],\n\toutput,\n});\n\nruleTester.run('import-path', importPathRule, {\n\tvalid: [\n\t\t// Already has .d.ts extension\n\t\t{\n\t\t\tcode: 'import type {Foo} from \"./foo.d.ts\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'import type {Bar} from \"../bar.d.ts\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'import {Baz} from \"./types/baz.d.ts\";',\n\t\t},\n\t\t// Non-relative imports are ignored\n\t\t{\n\t\t\tcode: 'import {something} from \"external-package\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'import type {Type} from \"@types/node\";',\n\t\t},\n\t\t// Export named declarations with .d.ts extension\n\t\t{\n\t\t\tcode: 'export type {Foo} from \"./foo.d.ts\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'export {Bar} from \"../bar.d.ts\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'export type {Baz as Qux} from \"./types/baz.d.ts\";',\n\t\t},\n\t\t// Export all declarations with .d.ts extension\n\t\t{\n\t\t\tcode: 'export * from \"./foo.d.ts\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'export * from \"../bar.d.ts\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'export * as Types from \"./types.d.ts\";',\n\t\t},\n\t\t// Non re-exports are ignored\n\t\t{\n\t\t\tcode: 'export {localVar};',\n\t\t},\n\t\t{\n\t\t\tcode: 'export type {LocalType};',\n\t\t},\n\t\t{\n\t\t\tcode: 'export type Foo = string;',\n\t\t},\n\t\t// Non-relative exports are ignored\n\t\t{\n\t\t\tcode: 'export {something} from \"external-package\";',\n\t\t},\n\t\t{\n\t\t\tcode: 'export * from \"@types/node\";',\n\t\t},\n\t],\n\tinvalid: [\n\t\t// Missing extension\n\t\tinvalidImport(\n\t\t\t'import type {Foo} from \"./foo\";',\n\t\t\t'import type {Foo} from \\'./foo.d.ts\\';',\n\t\t),\n\t\t// Wrong extension .ts\n\t\tinvalidImport(\n\t\t\t'import type {Bar} from \"../bar.ts\";',\n\t\t\t'import type {Bar} from \\'../bar.d.ts\\';',\n\t\t),\n\t\t// Wrong extension .js\n\t\tinvalidImport(\n\t\t\t'import type {Baz} from \"./types.js\";',\n\t\t\t'import type {Baz} from \\'./types.d.ts\\';',\n\t\t),\n\t\t// Deep path\n\t\tinvalidImport(\n\t\t\t'import type {Deep} from \"../../deep/path.tsx\";',\n\t\t\t'import type {Deep} from \\'../../deep/path.d.ts\\';',\n\t\t),\n\t\t// Export named declarations - missing extension\n\t\tinvalidImport(\n\t\t\t'export type {Foo} from \"./foo\";',\n\t\t\t'export type {Foo} from \\'./foo.d.ts\\';',\n\t\t),\n\t\tinvalidImport(\n\t\t\t'export {Bar} from \"../bar\";',\n\t\t\t'export {Bar} from \\'../bar.d.ts\\';',\n\t\t),\n\t\t// Export named declarations - wrong extension\n\t\tinvalidImport(\n\t\t\t'export type {Baz} from \"./types.ts\";',\n\t\t\t'export type {Baz} from \\'./types.d.ts\\';',\n\t\t),\n\t\tinvalidImport(\n\t\t\t'export {Qux} from \"./qux.js\";',\n\t\t\t'export {Qux} from \\'./qux.d.ts\\';',\n\t\t),\n\t\t// Export all declarations - missing extension\n\t\tinvalidImport(\n\t\t\t'export * from \"./foo\";',\n\t\t\t'export * from \\'./foo.d.ts\\';',\n\t\t),\n\t\tinvalidImport(\n\t\t\t'export * from \"../bar\";',\n\t\t\t'export * from \\'../bar.d.ts\\';',\n\t\t),\n\t\t// Export all declarations - wrong extension\n\t\tinvalidImport(\n\t\t\t'export * from \"./types.ts\";',\n\t\t\t'export * from \\'./types.d.ts\\';',\n\t\t),\n\t\tinvalidImport(\n\t\t\t'export * as AllTypes from \"../../all.js\";',\n\t\t\t'export * as AllTypes from \\'../../all.d.ts\\';',\n\t\t),\n\t\t// Wrong extension .d.d.ts\n\t\tinvalidImport(\n\t\t\t'import type {Foo} from \"./foo.d.d.ts\";',\n\t\t\t'import type {Foo} from \\'./foo.d.ts\\';',\n\t\t),\n\t],\n});\n" }, { "path": "lint-rules/require-export.js", "content": "export const requireExportRule = /** @type {const} */ ({\n\tmeta: {\n\t\ttype: 'problem',\n\t\tdocs: {\n\t\t\tdescription: 'Ensure .d.ts files always have `export {}` to avoid being treated as global',\n\t\t\tcategory: 'Best Practices',\n\t\t\trecommended: true,\n\t\t},\n\t\tmessages: {\n\t\t\tnoEmptyExport: 'File must have `export {}` to ensure it is treated as a module.',\n\t\t},\n\t\tfixable: 'code',\n\t},\n\tdefaultOptions: [],\n\tcreate(context) {\n\t\tconst filename = context.filename.replaceAll('\\\\', '/');\n\n\t\t// Only check source .d.ts files\n\t\tif (!filename.includes('/source/') || !filename.endsWith('.d.ts')) {\n\t\t\treturn {};\n\t\t}\n\n\t\tlet hasEmptyExport = false;\n\n\t\treturn {\n\t\t\tExportNamedDeclaration(node) {\n\t\t\t\t// Check if this is specifically `export {}`\n\t\t\t\tif (!node.declaration && node.specifiers.length === 0 && !node.source) {\n\t\t\t\t\thasEmptyExport = true;\n\t\t\t\t}\n\t\t\t},\n\t\t\t'Program:exit'(node) {\n\t\t\t\tif (!hasEmptyExport) {\n\t\t\t\t\tcontext.report({\n\t\t\t\t\t\tnode,\n\t\t\t\t\t\tmessageId: 'noEmptyExport',\n\t\t\t\t\t\tfix(fixer) {\n\t\t\t\t\t\t\t// Add export {} at the end of the file\n\t\t\t\t\t\t\treturn fixer.insertTextAfter(node, '\\nexport {};\\n');\n\t\t\t\t\t\t},\n\t\t\t\t\t});\n\t\t\t\t}\n\t\t\t},\n\t\t};\n\t},\n});\n" }, { "path": "lint-rules/require-export.test.js", "content": "import {createRuleTester} from './test-utils.js';\nimport {requireExportRule} from './require-export.js';\n\nconst ruleTester = createRuleTester();\n\nconst missingEmptyExport = (code, filename, output) => ({\n\tcode,\n\tfilename,\n\terrors: [{messageId: 'noEmptyExport'}],\n\toutput,\n});\n\nruleTester.run('require-export', requireExportRule, {\n\tvalid: [\n\t\t// Has export {}\n\t\t{\n\t\t\tcode: 'export {};',\n\t\t\tfilename: '/source/foo.d.ts',\n\t\t},\n\t\t// Has export {} with other exports\n\t\t{\n\t\t\tcode: 'export type Foo = string;\\nexport {};',\n\t\t\tfilename: '/source/bar.d.ts',\n\t\t},\n\t\t// Non-.d.ts files don't need export {}\n\t\t{\n\t\t\tcode: 'const x = 1;',\n\t\t\tfilename: '/source/foo.ts',\n\t\t},\n\t\t{\n\t\t\tcode: 'export const y = 2;',\n\t\t\tfilename: '/source/bar.js',\n\t\t},\n\t\t// Files outside source directory are ignored\n\t\t{\n\t\t\tcode: 'type Test = string;',\n\t\t\tfilename: '/test/foo.d.ts',\n\t\t},\n\t\t{\n\t\t\tcode: 'interface ITest {}',\n\t\t\tfilename: '/lib/bar.d.ts',\n\t\t},\n\t],\n\tinvalid: [\n\t\t// Missing export {} in empty file\n\t\tmissingEmptyExport('', '/source/foo.d.ts', '\\nexport {};\\n'),\n\t\t// Missing export {} with type declarations\n\t\tmissingEmptyExport(\n\t\t\t'export type Foo = string;',\n\t\t\t'/source/bar.d.ts',\n\t\t\t'export type Foo = string;\\nexport {};\\n',\n\t\t),\n\t\t// Missing export {} with interface\n\t\tmissingEmptyExport(\n\t\t\t'export interface IFoo {\\n\\tx: string;\\n}',\n\t\t\t'/source/baz.d.ts',\n\t\t\t'export interface IFoo {\\n\\tx: string;\\n}\\nexport {};\\n',\n\t\t),\n\t\t// Missing export {} with multiple exports\n\t\tmissingEmptyExport(\n\t\t\t'export type A = string;\\nexport type B = number;',\n\t\t\t'/source/multi.d.ts',\n\t\t\t'export type A = string;\\nexport type B = number;\\nexport {};\\n',\n\t\t),\n\t],\n});\n" }, { "path": "lint-rules/require-exported-types.js", "content": "import path from 'node:path';\nimport fs from 'node:fs';\n\nexport const requireExportedTypesRule = /** @type {const} */ ({\n\tmeta: {\n\t\ttype: 'suggestion',\n\t\tdocs: {\n\t\t\tdescription: 'Enforce that exported types are also exported from index.d.ts',\n\t\t\tcategory: 'Best Practices',\n\t\t\trecommended: true,\n\t\t},\n\t\tmessages: {\n\t\t\tmissingExport: 'Type `{{typeName}}` is exported from this file but not from index.d.ts. '\n\t\t\t\t+ 'Add it to index.d.ts or use `// eslint-disable-next-line type-fest/require-exported-types` to ignore.',\n\t\t\tnoTypeInfo: 'Rule requires TypeScript type information. Configure `parserServices` in your ESLint config.',\n\t\t},\n\t\tschema: [\n\t\t\t{\n\t\t\t\ttype: 'object',\n\t\t\t\tproperties: {\n\t\t\t\t\tindexFile: {\n\t\t\t\t\t\ttype: 'string',\n\t\t\t\t\t\tdescription: 'Path to the index file (default: \"index.d.ts\")',\n\t\t\t\t\t},\n\t\t\t\t},\n\t\t\t\tadditionalProperties: false,\n\t\t\t},\n\t\t],\n\t},\n\tdefaultOptions: [],\n\tcreate(context) {\n\t\t// Only run on TypeScript declaration files in source directory\n\t\t// Convert to forward slashes for consistent path checking across platforms\n\t\tconst filename = context.filename.replaceAll('\\\\', '/');\n\t\tif (!filename.includes('/source/') || !filename.endsWith('.d.ts')) {\n\t\t\treturn {};\n\t\t}\n\n\t\t// Skip internal files\n\t\tif (filename.includes('/internal/')) {\n\t\t\treturn {};\n\t\t}\n\n\t\tconst options = context.options?.[0] ?? {};\n\t\tconst indexFileName = options.indexFile ?? 'index.d.ts';\n\n\t\t// Get TypeScript type-aware services\n\t\tconst {parserServices} = context.sourceCode;\n\n\t\t// Type information is required for this rule\n\t\tif (!parserServices?.program || !parserServices?.esTreeNodeToTSNodeMap) {\n\t\t\t// Report once per file that type information is required\n\t\t\treturn {\n\t\t\t\t'Program'(node) {\n\t\t\t\t\tcontext.report({\n\t\t\t\t\t\tnode,\n\t\t\t\t\t\tmessageId: 'noTypeInfo',\n\t\t\t\t\t});\n\t\t\t\t},\n\t\t\t};\n\t\t}\n\n\t\tconst {program} = parserServices;\n\t\tconst checker = program.getTypeChecker();\n\n\t\t// Find project root\n\t\tlet projectRoot = path.dirname(filename);\n\t\twhile (projectRoot !== path.dirname(projectRoot)) {\n\t\t\tif (fs.existsSync(path.join(projectRoot, 'package.json'))) {\n\t\t\t\tbreak;\n\t\t\t}\n\n\t\t\tprojectRoot = path.dirname(projectRoot);\n\t\t}\n\n\t\tconst indexPath = path.join(projectRoot, indexFileName);\n\n\t\t// Get index exports (no caching to detect changes immediately)\n\t\tconst indexExports = new Set();\n\n\t\t// Get the source file for index.d.ts\n\t\tconst indexSourceFile = program.getSourceFile(indexPath);\n\t\tif (indexSourceFile) {\n\t\t\tconst indexSymbol = checker.getSymbolAtLocation(indexSourceFile);\n\t\t\tif (indexSymbol) {\n\t\t\t\tconst exports = checker.getExportsOfModule(indexSymbol);\n\t\t\t\tfor (const exportSymbol of exports) {\n\t\t\t\t\tindexExports.add(exportSymbol.name);\n\t\t\t\t}\n\t\t\t}\n\t\t}\n\n\t\t// State to track processed nodes\n\t\tconst processed = new Set();\n\n\t\t// Helper function to check exported type/interface\n\t\tconst checkExportedType = node => {\n\t\t\tconst typeName = node.id.name;\n\n\t\t\t// Skip types starting with underscore (internal/private convention)\n\t\t\tif (typeName.startsWith('_')) {\n\t\t\t\treturn;\n\t\t\t}\n\n\t\t\t// Skip if inside declare namespace\n\t\t\tconst ancestors = context.sourceCode.getAncestors(node);\n\t\t\tconst isInsideDeclareNamespace = ancestors.some(ancestor =>\n\t\t\t\tancestor.type === 'TSModuleDeclaration' && ancestor.declare,\n\t\t\t);\n\n\t\t\tif (isInsideDeclareNamespace) {\n\t\t\t\treturn;\n\t\t\t}\n\n\t\t\t// Skip if already processed\n\t\t\tif (processed.has(typeName)) {\n\t\t\t\treturn;\n\t\t\t}\n\n\t\t\tprocessed.add(typeName);\n\n\t\t\t// Report if not exported from index\n\t\t\tif (!indexExports.has(typeName)) {\n\t\t\t\tcontext.report({\n\t\t\t\t\tnode,\n\t\t\t\t\tmessageId: 'missingExport',\n\t\t\t\t\tdata: {typeName},\n\t\t\t\t});\n\t\t\t}\n\t\t};\n\n\t\treturn {\n\t\t\t// Handle: export type Foo = ...\n\t\t\t'ExportNamedDeclaration > TSTypeAliasDeclaration': checkExportedType,\n\n\t\t\t// Handle: export interface Foo { ... }\n\t\t\t'ExportNamedDeclaration > TSInterfaceDeclaration': checkExportedType,\n\n\t\t\t// Clean up cache periodically\n\t\t};\n\t},\n});\n" }, { "path": "lint-rules/require-exported-types.test.js", "content": "import {createTypeAwareRuleTester} from './test-utils.js';\nimport {requireExportedTypesRule} from './require-exported-types.js';\n\nconst packageContent = JSON.stringify({\n\tname: 'require-exported-types-fixture',\n}, null, '\\t');\n\nconst indexContent = 'export {type ExportedType} from \\'./source/exported-type\\';\\n';\nconst exportedTypeContent = 'export type ExportedType = {\\n\\tvalue: string;\\n};\\n';\nconst internalTypeContent = 'export type InternalType = {\\n\\tvalue: boolean;\\n};\\n';\nconst nestedInternalTypeContent = 'export interface NestedInternalType {\\n\\tvalue: string;\\n}\\n';\nconst privateTypeContent = 'export type _HiddenType = string;\\n';\nconst missingTypeContent = 'export type MissingType = {\\n\\tvalue: number;\\n};\\n';\nconst unexportedMultipleContent = 'export type FirstUnexportedType = string;\\nexport interface SecondUnexportedInterface {\\n\\tvalue: boolean;\\n}\\n';\nconst implementationContent = 'export const value = 1;\\n';\nconst testDeclarationContent = 'export type Test = number;\\n';\nconst libDeclarationContent = 'export interface LibTest {\\n\\tvalue: string;\\n}\\n';\n\nconst {ruleTester, fixturePath} = createTypeAwareRuleTester({\n\t'package.json': `${packageContent}\\n`,\n\t'index.d.ts': indexContent,\n\t'source/exported-type.d.ts': undefined,\n\t'source/internal/internal-type.d.ts': undefined,\n\t'source/internal/nested/deep.d.ts': undefined,\n\t'source/private-type.d.ts': undefined,\n\t'source/missing-type.d.ts': undefined,\n\t'source/unexported-multiple.d.ts': undefined,\n\t'source/implementation.ts': undefined,\n\t'test/test.d.ts': undefined,\n\t'lib/test.d.ts': undefined,\n});\n\n// Type-aware rule tests rely on the generated fixture project above.\nconst missingExportError = typeName => ({\n\tmessageId: 'missingExport',\n\tdata: {typeName},\n});\n\nruleTester.run('require-exported-types', requireExportedTypesRule, {\n\tvalid: [\n\t\t{\n\t\t\tcode: exportedTypeContent,\n\t\t\tfilename: fixturePath('source/exported-type.d.ts'),\n\t\t},\n\t\t{\n\t\t\tcode: privateTypeContent,\n\t\t\tfilename: fixturePath('source/private-type.d.ts'),\n\t\t},\n\t\t{\n\t\t\tcode: internalTypeContent,\n\t\t\tfilename: fixturePath('source/internal/internal-type.d.ts'),\n\t\t},\n\t\t{\n\t\t\tcode: nestedInternalTypeContent,\n\t\t\tfilename: fixturePath('source/internal/nested/deep.d.ts'),\n\t\t},\n\t\t{\n\t\t\tcode: implementationContent,\n\t\t\tfilename: fixturePath('source/implementation.ts'),\n\t\t},\n\t\t{\n\t\t\tcode: testDeclarationContent,\n\t\t\tfilename: fixturePath('test/test.d.ts'),\n\t\t},\n\t\t{\n\t\t\tcode: libDeclarationContent,\n\t\t\tfilename: fixturePath('lib/test.d.ts'),\n\t\t},\n\t],\n\tinvalid: [\n\t\t{\n\t\t\tcode: missingTypeContent,\n\t\t\tfilename: fixturePath('source/missing-type.d.ts'),\n\t\t\terrors: [missingExportError('MissingType')],\n\t\t},\n\t\t{\n\t\t\tcode: unexportedMultipleContent,\n\t\t\tfilename: fixturePath('source/unexported-multiple.d.ts'),\n\t\t\terrors: [\n\t\t\t\tmissingExportError('FirstUnexportedType'),\n\t\t\t\tmissingExportError('SecondUnexportedInterface'),\n\t\t\t],\n\t\t},\n\t],\n});\n" }, { "path": "lint-rules/source-files-extension.js", "content": "import path from 'node:path';\n\nexport const sourceFilesExtensionRule = /** @type {const} */ ({\n\tmeta: {\n\t\ttype: 'problem',\n\t\tdocs: {\n\t\t\tdescription: 'Enforces source files to end with a \\'.d.ts\\' extension.',\n\t\t},\n\t\tfixable: 'code',\n\t\tmessages: {\n\t\t\tincorrectFilename:\n\t\t\t\t'Filename \\'{{filename}}\\' must end with a \\'.d.ts\\' extension. Use \\'{{fixedFilename}}\\' instead.',\n\t\t},\n\t\tschema: [],\n\t},\n\tdefaultOptions: [],\n\tcreate(context) {\n\t\tconst filename = path.basename(context.filename);\n\t\tconst firstDotIndex = filename.indexOf('.');\n\t\tconst extension = firstDotIndex === -1 ? '' : filename.slice(firstDotIndex);\n\n\t\tif (extension === '.d.ts') {\n\t\t\treturn {};\n\t\t}\n\n\t\treturn {\n\t\t\tProgram(node) {\n\t\t\t\tconst filenameWithoutExtension = extension.length > 0\n\t\t\t\t\t? filename.slice(0, -extension.length)\n\t\t\t\t\t: filename;\n\t\t\t\tconst fixedFilename = `${filenameWithoutExtension}.d.ts`;\n\n\t\t\t\tcontext.report({\n\t\t\t\t\tloc: {column: 0, line: 1}, // Report error on start of the file\n\t\t\t\t\tnode,\n\t\t\t\t\tmessageId: 'incorrectFilename',\n\t\t\t\t\tdata: {filename, fixedFilename},\n\t\t\t\t});\n\t\t\t},\n\t\t};\n\t},\n});\n" }, { "path": "lint-rules/source-files-extension.test.js", "content": "import {createRuleTester} from './test-utils.js';\nimport {sourceFilesExtensionRule} from './source-files-extension.js';\n\nconst ruleTester = createRuleTester();\n\nconst invalidSourceFile = (filename, code = '') => ({\n\tcode,\n\tfilename,\n\terrors: [{messageId: 'incorrectFilename'}],\n});\n\nruleTester.run('source-files-extension', sourceFilesExtensionRule, {\n\tvalid: [\n\t\t// Correct .d.ts extension\n\t\t{\n\t\t\tcode: '',\n\t\t\tfilename: '/source/foo.d.ts',\n\t\t},\n\t\t{\n\t\t\tcode: '',\n\t\t\tfilename: '/source/types/bar.d.ts',\n\t\t},\n\t\t{\n\t\t\tcode: '',\n\t\t\tfilename: '/source/deeply/nested/file.d.ts',\n\t\t},\n\t],\n\tinvalid: [\n\t\t// Wrong .ts extension\n\t\tinvalidSourceFile('/source/foo.ts'),\n\t\t// Wrong .js extension\n\t\tinvalidSourceFile('/source/foo.js'),\n\t\t// No extension\n\t\tinvalidSourceFile('/source/bar'),\n\t\t// Wrong .tsx extension\n\t\tinvalidSourceFile('/source/component.tsx'),\n\t\t// Wrong .mjs extension\n\t\tinvalidSourceFile('/source/module.mjs'),\n\t],\n});\n" }, { "path": "lint-rules/test-utils.js", "content": "import fs from 'node:fs';\nimport os from 'node:os';\nimport path from 'node:path';\nimport {RuleTester} from 'eslint';\nimport tsParser from '@typescript-eslint/parser';\nimport dedent from 'dedent';\n\nexport const createRuleTester = (overrides = {}) => {\n\tconst {\n\t\tlanguageOptions: overrideLanguageOptions = {},\n\t\t...restOverrides\n\t} = overrides;\n\n\tconst {\n\t\tparserOptions: overrideParserOptions = {},\n\t\t...otherLanguageOptions\n\t} = overrideLanguageOptions;\n\n\treturn new RuleTester({\n\t\t...restOverrides,\n\t\tlanguageOptions: {\n\t\t\tecmaVersion: 'latest',\n\t\t\tsourceType: 'module',\n\t\t\tparser: tsParser,\n\t\t\t...otherLanguageOptions,\n\t\t\tparserOptions: {\n\t\t\t\t...overrideParserOptions,\n\t\t\t},\n\t\t},\n\t});\n};\n\nconst defaultTypeAwareTsconfig = {\n\tcompilerOptions: {\n\t\tdeclaration: true,\n\t\temitDeclarationOnly: true,\n\t\tmodule: 'ESNext',\n\t\tmoduleResolution: 'Bundler',\n\t\tskipLibCheck: true,\n\t\tstrict: true,\n\t\ttarget: 'ES2022',\n\t},\n\tinclude: [\n\t\t'*.d.ts',\n\t\t'source/**/*.*',\n\t\t'lib/**/*.d.ts',\n\t\t'test/**/*.d.ts',\n\t],\n};\n\nexport const createTypeAwareRuleTester = (fixtureFiles, options = {}) => {\n\tconst fixtureRoot = fs.mkdtempSync(path.join(os.tmpdir(), 'type-fest-type-aware-'));\n\n\tconst writeFixture = (relativePath, content) => {\n\t\tconst absolutePath = path.join(fixtureRoot, relativePath);\n\t\tfs.mkdirSync(path.dirname(absolutePath), {recursive: true});\n\t\tfs.writeFileSync(absolutePath, content ?? '');\n\t};\n\n\tfor (const [relativePath, content] of Object.entries(fixtureFiles)) {\n\t\twriteFixture(relativePath, content);\n\t}\n\n\tconst hasRuleTesterOption = Object.hasOwn(options, 'ruleTester');\n\tconst hasTsconfigOption = Object.hasOwn(options, 'tsconfig');\n\tconst ruleTesterOverrides = hasRuleTesterOption || hasTsconfigOption ? options.ruleTester ?? {} : options;\n\tconst tsconfig = hasRuleTesterOption || hasTsconfigOption\n\t\t? options.tsconfig ?? defaultTypeAwareTsconfig\n\t\t: defaultTypeAwareTsconfig;\n\n\tif (!('tsconfig.json' in fixtureFiles)) {\n\t\twriteFixture('tsconfig.json', `${JSON.stringify(tsconfig, null, '\\t')}\\n`);\n\t}\n\n\tconst overrideLanguageOptions = ruleTesterOverrides.languageOptions ?? {};\n\tconst overrideParserOptions = overrideLanguageOptions.parserOptions ?? {};\n\tconst overrideProjectService = overrideParserOptions.projectService ?? {};\n\tconst ruleTester = createRuleTester({\n\t\t...ruleTesterOverrides,\n\t\tlanguageOptions: {\n\t\t\t...overrideLanguageOptions,\n\t\t\tparserOptions: {\n\t\t\t\t...overrideParserOptions,\n\t\t\t\tprojectService: {\n\t\t\t\t\tallowDefaultProject: ['*.ts*'],\n\t\t\t\t\t...overrideProjectService,\n\t\t\t\t},\n\t\t\t\ttsconfigRootDir: fixtureRoot,\n\t\t\t},\n\t\t},\n\t});\n\n\tconst fixturePath = relativePath => path.join(fixtureRoot, relativePath);\n\n\treturn {\n\t\truleTester,\n\t\tfixtureRoot,\n\t\tfixturePath,\n\t\twriteFixture,\n\t};\n};\n\nexport const dedenter = dedent.withOptions({alignValues: true});\n\n/**\nReturns the specified code in a fenced code block, with an optional language tag.\n\n@example\n```\nfence('type A = string;');\n// Returns:\n// ```\n// type A = string;\n// ```\n\nfence(`import {RemovePrefix} from 'type-fest';\n\ntype A = RemovePrefix<'onChange', 'on'>;\n//=> 'Change'`, 'ts');\n// Returns:\n// ```ts\n// import {RemovePrefix} from 'type-fest';\n\n// type A = RemovePrefix<'onChange', 'on'>;\n// //=> 'Change'\n// ```\n```\n*/\nexport const fence = (code, lang = '') =>\n\tdedenter`\n\t\t\\`\\`\\`${lang}\n\t\t${code}\n\t\t\\`\\`\\`\n\t`;\n\n/**\nReturns the specified lines as a JSDoc comment, placing each specified line on a new line.\n\n@example\n```\njsdoc('Some description.', 'Note: Some note.');\n// Returns:\n// /**\n// Some description.\n// Note: Some note.\n// *​/\n\njsdoc('@example', '```\\ntype A = string;\\n```', '@category Test');\n// Returns;\n// /**\n// @example\n// ```\n// type A = string;\n// ```\n// @category Test\n// *​/\n```\n*/\nexport const jsdoc = (...lines) =>\n\tdedenter`\n\t\t/**\n\t\t${lines.join('\\n')}\n\t\t*/\n\t`;\n\n/**\nReturns an exported type for each provided prefix, with each prefix placed directly above its corresponding type declaration.\n\n@example\n```\nexportType(\n\t'// Some comment',\n\t'type Test = string;',\n\t'/**\\nSome description.\\nNote: Some note.\\n*​/'\n);\n// Returns:\n// // Some comment\n// export type T0 = string;\n//\n// type Test = string;\n// export type T1 = string;\n//\n// /**\n// Some description.\n// Note: Some note.\n// *​/\n// export type T2 = string;\n*/\nexport const exportType = (...prefixes) =>\n\tprefixes\n\t\t.map((doc, i) => dedenter`\n\t\t\t${doc}\n\t\t\texport type T${i} = string;\n\t\t`)\n\t\t.join('\\n\\n');\n\n/**\nReturns an exported \"Options\" object type containing a property for each specified prefix, with each prefix placed directly above its corresponding property declaration.\n\n@example\n```\nexportOption(\n\t'// Some comment',\n\t'type Test = string;',\n\t'/**\\nSome description.\\nNote: Some note.\\n*​/'\n);\n// Returns:\n// export type TOptions = {\n// \t// Some comment\n// \tp0: string;\n\n// \ttest: string;\n// \tp1: string;\n\n// \t/**\n// \tSome description.\n// \tNote: Some note.\n// \t*​/\n// \tp2: string;\n// };\n```\n*/\nexport const exportOption = (...prefixes) =>\n\tdedenter`\n\t\texport type TOptions = {\n\t\t\t${prefixes\n\t\t\t\t.map((doc, i) => dedenter`\n\t\t\t\t\t${doc}\n\t\t\t\t\tp${i}: string;\n\t\t\t\t`)\n\t\t\t\t.join('\\n\\n')}\n\t\t};\n\t`;\n\n/**\nReturns an exported type for each provided prefix, and an exported \"Options\" object type containing a property for each specified prefix, with each prefix placed directly above its corresponding declaration.\n\n@example\n```\nexportTypeAndOption('// Some comment', '/**\\nSome JSDoc\\n*​/');\n// Returns:\n// // Some comment\n// type T0 = string;\n\n// /**\n// Some JSDoc\n// *​/\n// type T1 = string;\n\n// type TOptions = {\n// \t// Some comment\n// \tp0: string;\n\n// \t/**\n// \tSome JSDoc\n// \t*​/\n// \tp1: string;\n// };\n```\n*/\nexport const exportTypeAndOption = (...prefixes) =>\n\tdedenter`\n\t\t${exportType(...prefixes)}\n\n\t\t${exportOption(...prefixes)}\n\t`;\n\n/**\n@typedef {{\n\tline: number;\n\ttextBeforeStart: string;\n\truleId?: string;\n\tmessageId?: string;\n} & ({ target: string } | { endLine: number; textBeforeEnd: string })} ErrorAtProps\n\n@param {ErrorAtProps} props\n@returns {{line: number, column: number, endLine: number, endColumn: number, ruleId?: string, messageId?: string}}\n*/\nexport const errorAt = props => {\n\tconst {line, textBeforeStart, ruleId, messageId} = props;\n\n\tconst column = textBeforeStart.length + 1;\n\tconst endColumn = 'textBeforeEnd' in props ? props.textBeforeEnd.length + 1 : column + props.target.length;\n\n\tconst endLine = 'endLine' in props ? props.endLine : line;\n\n\treturn {\n\t\t...(ruleId && {ruleId}),\n\t\t...(messageId && {messageId}),\n\t\tline, // 1-based, inclusive\n\t\tcolumn, // 1-based, inclusive\n\t\tendLine, // 1-based, inclusive\n\t\tendColumn, // 1-based, exclusive\n\t};\n};\n\n/// Code samples\nexport const code1 = dedenter`\nimport type {Sum} from 'type-fest';\n\ntype A = Sum<1, 2>;\n//=> 3\n`;\n\nexport const code2 = dedenter`\nimport type {LiteralToPrimitiveDeep} from 'type-fest';\n\nconst config = {appName: 'MyApp', version: '1.0.0'} as const;\n\ndeclare function updateConfig(newConfig: LiteralToPrimitiveDeep): void;\n\nupdateConfig({appName: 'MyUpdatedApp', version: '2.0.0'});\n`;\n" }, { "path": "lint-rules/validate-jsdoc-codeblocks.js", "content": "import path from 'node:path';\nimport ts from 'typescript';\nimport {createFSBackedSystem, createVirtualTypeScriptEnvironment} from '@typescript/vfs';\n\nconst CODEBLOCK_REGEX = /(?```(?:ts|typescript)?\\n)(?[\\s\\S]*?)```/g;\nconst FILENAME = 'example-codeblock.ts';\nconst TWOSLASH_COMMENT = '//=>';\n\nconst compilerOptions = {\n\tlib: ['lib.es2023.d.ts', 'lib.dom.d.ts', 'lib.dom.iterable.d.ts'],\n\ttarget: ts.ScriptTarget.ESNext,\n\tmodule: ts.ModuleKind.Node20,\n\tmoduleResolution: ts.ModuleResolutionKind.Node16,\n\tstrict: true,\n\tnoImplicitReturns: true,\n\tnoImplicitOverride: true,\n\tnoUnusedLocals: false, // This is intentionally disabled\n\tnoUnusedParameters: true,\n\tnoFallthroughCasesInSwitch: true,\n\tnoUncheckedIndexedAccess: true,\n\tnoPropertyAccessFromIndexSignature: true,\n\tnoUncheckedSideEffectImports: true,\n\tuseDefineForClassFields: true,\n\texactOptionalPropertyTypes: true,\n};\n\nconst virtualFsMap = new Map();\nvirtualFsMap.set(FILENAME, '// Can\\'t be empty');\n\nconst rootDir = path.join(import.meta.dirname, '..');\nconst system = createFSBackedSystem(virtualFsMap, rootDir, ts);\nconst defaultEnv = createVirtualTypeScriptEnvironment(system, [FILENAME], ts, compilerOptions);\n\nfunction parseCompilerOptions(code) {\n\tconst options = {};\n\tconst lines = code.split('\\n');\n\n\tfor (const line of lines) {\n\t\tif (!line.trim()) {\n\t\t\t// Skip empty lines\n\t\t\tcontinue;\n\t\t}\n\n\t\tconst match = line.match(/^\\s*\\/\\/ @(\\w+): (.*)$/);\n\t\tif (!match) {\n\t\t\t// Stop parsing at the first non-matching line\n\t\t\treturn options;\n\t\t}\n\n\t\tconst [, key, value] = match;\n\t\tconst trimmedValue = value.trim();\n\n\t\ttry {\n\t\t\toptions[key] = JSON.parse(trimmedValue);\n\t\t} catch {\n\t\t\toptions[key] = trimmedValue;\n\t\t}\n\t}\n\n\treturn options;\n}\n\nfunction getJSDocNode(sourceCode, node) {\n\tlet previousToken = sourceCode.getTokenBefore(node, {includeComments: true});\n\n\t// Skip over any line comments immediately before the node\n\twhile (previousToken && previousToken.type === 'Line') {\n\t\tpreviousToken = sourceCode.getTokenBefore(previousToken, {includeComments: true});\n\t}\n\n\tif (previousToken && previousToken.type === 'Block' && previousToken.value.startsWith('*')) {\n\t\treturn previousToken;\n\t}\n\n\treturn undefined;\n}\n\nexport const validateJSDocCodeblocksRule = /** @type {const} */ ({\n\tmeta: {\n\t\ttype: 'suggestion',\n\t\tdocs: {\n\t\t\tdescription: 'Ensures JSDoc example codeblocks don\\'t have errors',\n\t\t},\n\t\tfixable: 'code',\n\t\tmessages: {\n\t\t\tinvalidCodeblock: '{{errorMessage}}',\n\t\t\tincorrectTwoslashType: 'Expected twoslash comment to be: {{expectedComment}}, but found: {{actualComment}}',\n\t\t\tincorrectTwoslashFormat: 'Expected twoslash comment to be: {{expectedComment}}, but found: {{actualComment}}',\n\t\t},\n\t\tschema: [{\n\t\t\ttype: 'object',\n\t\t\tproperties: {\n\t\t\t\tverbosityLevels: {\n\t\t\t\t\ttype: 'array',\n\t\t\t\t\tuniqueItems: true,\n\t\t\t\t\titems: {\n\t\t\t\t\t\tminimum: 0,\n\t\t\t\t\t\ttype: 'number',\n\t\t\t\t\t},\n\t\t\t\t},\n\t\t\t},\n\t\t}],\n\t\t/** @type {unknown[]} */\n\t\tdefaultOptions: [{\n\t\t\tverbosityLevels: [],\n\t\t}],\n\t},\n\tcreate(context) {\n\t\tconst filename = context.filename.replaceAll('\\\\', '/');\n\n\t\t// Skip internal files\n\t\tif (filename.includes('/internal/')) {\n\t\t\treturn {};\n\t\t}\n\n\t\ttry {\n\t\t\tdefaultEnv.updateFile(context.filename, context.sourceCode.getText());\n\t\t} catch {\n\t\t\t// Ignore\n\t\t}\n\n\t\treturn {\n\t\t\tTSTypeAliasDeclaration(node) {\n\t\t\t\tconst {parent} = node;\n\n\t\t\t\t// Skip if type is not exported or starts with an underscore (private/internal)\n\t\t\t\tif (parent.type !== 'ExportNamedDeclaration' || node.id.name.startsWith('_')) {\n\t\t\t\t\treturn;\n\t\t\t\t}\n\n\t\t\t\tconst previousNodes = [];\n\t\t\t\tconst jsdocForExport = getJSDocNode(context.sourceCode, parent);\n\t\t\t\tif (jsdocForExport) {\n\t\t\t\t\tpreviousNodes.push(jsdocForExport);\n\t\t\t\t}\n\n\t\t\t\t// Handle JSDoc blocks for options\n\t\t\t\tif (node.id.name.endsWith('Options') && node.typeAnnotation.type === 'TSTypeLiteral') {\n\t\t\t\t\tfor (const member of node.typeAnnotation.members) {\n\t\t\t\t\t\tconst jsdocForMember = getJSDocNode(context.sourceCode, member);\n\t\t\t\t\t\tif (jsdocForMember) {\n\t\t\t\t\t\t\tpreviousNodes.push(jsdocForMember);\n\t\t\t\t\t\t}\n\t\t\t\t\t}\n\t\t\t\t}\n\n\t\t\t\tfor (const previousNode of previousNodes) {\n\t\t\t\t\tconst comment = previousNode.value;\n\n\t\t\t\t\tfor (const match of comment.matchAll(CODEBLOCK_REGEX)) {\n\t\t\t\t\t\tconst {code, openingFence} = match.groups ?? {};\n\n\t\t\t\t\t\t// Skip empty code blocks\n\t\t\t\t\t\tif (!code || !openingFence) {\n\t\t\t\t\t\t\tcontinue;\n\t\t\t\t\t\t}\n\n\t\t\t\t\t\tconst matchOffset = match.index + openingFence.length + 2; // Add `2` because `comment` doesn't include the starting `/*`\n\t\t\t\t\t\tconst codeStartIndex = previousNode.range[0] + matchOffset;\n\n\t\t\t\t\t\tconst overrides = parseCompilerOptions(code);\n\t\t\t\t\t\tlet env = defaultEnv;\n\n\t\t\t\t\t\tif (Object.keys(overrides).length > 0) {\n\t\t\t\t\t\t\tconst {options, errors} = ts.convertCompilerOptionsFromJson(overrides, rootDir);\n\n\t\t\t\t\t\t\tif (errors.length === 0) {\n\t\t\t\t\t\t\t\t// Create a new environment with overridden options\n\t\t\t\t\t\t\t\tenv = createVirtualTypeScriptEnvironment(system, [FILENAME], ts, {...compilerOptions, ...options});\n\t\t\t\t\t\t\t}\n\t\t\t\t\t\t}\n\n\t\t\t\t\t\tenv.updateFile(FILENAME, code);\n\t\t\t\t\t\tconst syntacticDiagnostics = env.languageService.getSyntacticDiagnostics(FILENAME);\n\t\t\t\t\t\tconst semanticDiagnostics = env.languageService.getSemanticDiagnostics(FILENAME);\n\t\t\t\t\t\tconst diagnostics = syntacticDiagnostics.length > 0 ? syntacticDiagnostics : semanticDiagnostics; // Show semantic errors only if there are no syntactic errors\n\n\t\t\t\t\t\tfor (const diagnostic of diagnostics) {\n\t\t\t\t\t\t\t// If diagnostic location is not available, report on the entire code block\n\t\t\t\t\t\t\tconst diagnosticStart = codeStartIndex + (diagnostic.start ?? 0);\n\t\t\t\t\t\t\tconst diagnosticEnd = diagnosticStart + (diagnostic.length ?? code.length);\n\n\t\t\t\t\t\t\tcontext.report({\n\t\t\t\t\t\t\t\tloc: {\n\t\t\t\t\t\t\t\t\tstart: context.sourceCode.getLocFromIndex(diagnosticStart),\n\t\t\t\t\t\t\t\t\tend: context.sourceCode.getLocFromIndex(diagnosticEnd),\n\t\t\t\t\t\t\t\t},\n\t\t\t\t\t\t\t\tmessageId: 'invalidCodeblock',\n\t\t\t\t\t\t\t\tdata: {\n\t\t\t\t\t\t\t\t\terrorMessage: ts.flattenDiagnosticMessageText(diagnostic.messageText, '\\n'),\n\t\t\t\t\t\t\t\t},\n\t\t\t\t\t\t\t});\n\t\t\t\t\t\t}\n\n\t\t\t\t\t\tif (diagnostics.length === 0) {\n\t\t\t\t\t\t\tvalidateTwoslashTypes(context, env, code, codeStartIndex);\n\t\t\t\t\t\t}\n\t\t\t\t\t}\n\t\t\t\t}\n\t\t\t},\n\t\t};\n\t},\n});\n\nfunction getLeftmostQuickInfo(env, line, lineOffset, verbosityLevel) {\n\tfor (let i = 0; i < line.length; i++) {\n\t\tconst quickInfo = env.languageService.getQuickInfoAtPosition(FILENAME, lineOffset + i, undefined, verbosityLevel);\n\t\tif (quickInfo?.displayParts) {\n\t\t\treturn quickInfo;\n\t\t}\n\t}\n}\n\nfunction extractTypeFromQuickInfo(quickInfo) {\n\tconst {displayParts} = quickInfo;\n\n\t// For interfaces and enums, return everything after the keyword\n\tconst keywordIndex = displayParts.findIndex(\n\t\tpart => part.kind === 'keyword' && ['interface', 'enum'].includes(part.text),\n\t);\n\n\tif (keywordIndex !== -1) {\n\t\treturn displayParts.slice(keywordIndex + 1).map(part => part.text).join('').trim();\n\t}\n\n\tlet depth = 0;\n\tconst separatorIndex = displayParts.findIndex(part => {\n\t\tif (part.kind === 'punctuation') {\n\t\t\tif (['(', '{', '<'].includes(part.text)) {\n\t\t\t\tdepth++;\n\t\t\t} else if ([')', '}', '>'].includes(part.text)) {\n\t\t\t\tdepth--;\n\t\t\t} else if (part.text === ':' && depth === 0) {\n\t\t\t\treturn true;\n\t\t\t}\n\t\t} else if (part.kind === 'operator' && part.text === '=' && depth === 0) {\n\t\t\treturn true;\n\t\t}\n\n\t\treturn false;\n\t});\n\n\t// If `separatorIndex` is `-1` (not found), return the entire thing\n\treturn displayParts.slice(separatorIndex + 1).map(part => part.text).join('').trim();\n}\n\nfunction normalizeType(type, onlySortNumbers = false) {\n\tconst sourceFile = ts.createSourceFile(\n\t\t'twoslash-type.ts',\n\t\t`declare const test: ${type};`,\n\t\tts.ScriptTarget.Latest,\n\t);\n\n\tconst typeNode = sourceFile.statements[0].declarationList.declarations[0].type;\n\n\tconst print = node => ts.createPrinter().printNode(ts.EmitHint.Unspecified, node, sourceFile);\n\n\tconst isNumeric = v => v.trim() !== '' && Number.isFinite(Number(v));\n\n\tconst visit = node => {\n\t\tnode = ts.visitEachChild(node, visit, undefined);\n\n\t\tif (ts.isUnionTypeNode(node)) {\n\t\t\tlet types = node.types.map(t => [print(t), t]);\n\n\t\t\tif (onlySortNumbers) {\n\t\t\t\t// Sort only numeric members while keeping non-numeric members at their original positions\n\t\t\t\tconst sortedNumericTypes = types.filter(([a]) => isNumeric(a)).sort(([a], [b]) => Number(a) - Number(b));\n\t\t\t\tlet numericIndex = 0;\n\t\t\t\ttypes = types.map(t => isNumeric(t[0]) ? sortedNumericTypes[numericIndex++][1] : t[1]);\n\t\t\t} else {\n\t\t\t\ttypes = types\n\t\t\t\t\t.sort(([a], [b]) => a < b ? -1 : (a > b ? 1 : 0))\n\t\t\t\t\t.map(t => t[1]);\n\t\t\t}\n\n\t\t\treturn ts.factory.updateUnionTypeNode(\n\t\t\t\tnode,\n\t\t\t\tts.factory.createNodeArray(types),\n\t\t\t);\n\t\t}\n\n\t\t// Prefer single-line formatting for tuple types\n\t\tif (ts.isTupleTypeNode(node)) {\n\t\t\tconst updated = ts.factory.createTupleTypeNode(node.elements);\n\t\t\tts.setEmitFlags(updated, ts.EmitFlags.SingleLine);\n\t\t\treturn updated;\n\t\t}\n\n\t\t// Replace double-quoted string literals with single-quoted ones\n\t\tif (ts.isStringLiteral(node)) {\n\t\t\tconst updated = ts.factory.createStringLiteral(node.text, true);\n\t\t\t// Preserve non-ASCII characters like emojis.\n\t\t\tts.setEmitFlags(updated, ts.EmitFlags.NoAsciiEscaping);\n\t\t\treturn updated;\n\t\t}\n\n\t\treturn node;\n\t};\n\n\treturn print(visit(typeNode)).replaceAll(/^( +)/gm, indentation => {\n\t\t// Replace spaces used for indentation with tabs\n\t\tconst spacesPerTab = 4;\n\t\tconst tabCount = Math.floor(indentation.length / spacesPerTab);\n\t\tconst remainingSpaces = indentation.length % spacesPerTab;\n\t\treturn '\\t'.repeat(tabCount) + ' '.repeat(remainingSpaces);\n\t});\n}\n\nfunction getCommentForType(type) {\n\tlet comment = type;\n\n\tif (type.length < 80) {\n\t\tcomment = type\n\t\t\t.replaceAll(/\\r?\\n\\s*/g, ' ') // Collapse into single line\n\t\t\t.replaceAll(/{\\s+/g, '{') // Remove spaces after `{`\n\t\t\t.replaceAll(/\\s+}/g, '}') // Remove spaces before `}`\n\t\t\t.replaceAll(/;(?=})/g, ''); // Remove semicolons before `}`\n\t}\n\n\treturn `${TWOSLASH_COMMENT} ${comment.replaceAll('\\n', '\\n// ')}`;\n}\n\nfunction reportTypeMismatch({context, messageId, start, end, data, fix}) {\n\tcontext.report({\n\t\tloc: {\n\t\t\tstart: context.sourceCode.getLocFromIndex(start),\n\t\t\tend: context.sourceCode.getLocFromIndex(end),\n\t\t},\n\t\tmessageId,\n\t\tdata,\n\t\tfix(fixer) {\n\t\t\treturn fixer.replaceTextRange([start, end], fix);\n\t\t},\n\t});\n}\n\nfunction validateTwoslashTypes(context, env, code, codeStartIndex) {\n\tconst sourceFile = env.languageService.getProgram().getSourceFile(FILENAME);\n\tconst lines = code.split('\\n');\n\n\tconst specifiedVerbosityLevels = context.options[0].verbosityLevels;\n\tconst verbosityLevels = [0, ...specifiedVerbosityLevels, Infinity]; // Keep `Infinity` last since suggestion logic relies on the order\n\n\tfor (const [index, line] of lines.entries()) {\n\t\tconst dedentedLine = line.trimStart();\n\t\tif (!dedentedLine.startsWith(TWOSLASH_COMMENT)) {\n\t\t\tcontinue;\n\t\t}\n\n\t\tconst previousLineIndex = index - 1;\n\t\tif (previousLineIndex < 0) {\n\t\t\tcontinue;\n\t\t}\n\n\t\tlet rawActualType = dedentedLine.slice(TWOSLASH_COMMENT.length);\n\t\tlet actualComment = dedentedLine;\n\t\tlet actualCommentEndLine = index;\n\n\t\tfor (let i = index + 1; i < lines.length; i++) {\n\t\t\tconst dedentedNextLine = lines[i].trimStart();\n\t\t\tif (!dedentedNextLine.startsWith('//') || dedentedNextLine.startsWith(TWOSLASH_COMMENT)) {\n\t\t\t\tbreak;\n\t\t\t}\n\n\t\t\tactualComment += '\\n' + dedentedNextLine;\n\t\t\trawActualType += '\\n' + dedentedNextLine.slice(2); // Remove the `//` from start\n\t\t\tactualCommentEndLine = i;\n\t\t}\n\n\t\tconst previousLine = lines[previousLineIndex];\n\t\tconst previousLineOffset = sourceFile.getPositionOfLineAndCharacter(previousLineIndex, 0);\n\n\t\tconst actualCommentIndex = line.indexOf(TWOSLASH_COMMENT);\n\n\t\tconst actualCommentStartOffset = sourceFile.getPositionOfLineAndCharacter(index, actualCommentIndex);\n\t\tconst actualCommentEndOffset = sourceFile.getPositionOfLineAndCharacter(actualCommentEndLine, lines[actualCommentEndLine].length);\n\n\t\tconst start = codeStartIndex + actualCommentStartOffset;\n\t\tconst end = codeStartIndex + actualCommentEndOffset;\n\n\t\tconst indent = line.slice(0, actualCommentIndex);\n\n\t\tconst quickInfos = verbosityLevels\n\t\t\t.map(verbosity => getLeftmostQuickInfo(env, previousLine, previousLineOffset, verbosity))\n\t\t\t.filter(qi => qi?.displayParts);\n\n\t\tif (quickInfos.length > 0) {\n\t\t\tconst expectedTypes = quickInfos.map(qi => normalizeType(extractTypeFromQuickInfo(qi)));\n\t\t\tconst actualType = normalizeType(rawActualType);\n\n\t\t\tif (expectedTypes.includes(actualType)) {\n\t\t\t\t// If the types match, check for formatting errors and unordered numbers in unions\n\t\t\t\tconst expectedComment = getCommentForType(normalizeType(rawActualType, true));\n\n\t\t\t\tif (actualComment !== expectedComment) {\n\t\t\t\t\treportTypeMismatch({\n\t\t\t\t\t\tmessageId: 'incorrectTwoslashFormat',\n\t\t\t\t\t\tcontext,\n\t\t\t\t\t\tstart,\n\t\t\t\t\t\tend,\n\t\t\t\t\t\tdata: {expectedComment, actualComment},\n\t\t\t\t\t\tfix: expectedComment.replaceAll('\\n', `\\n${indent}`),\n\t\t\t\t\t});\n\t\t\t\t}\n\t\t\t} else {\n\t\t\t\t// For suggestion, use infinite verbosity, and it should be the last one\n\t\t\t\tconst expectedComment = getCommentForType(expectedTypes.at(-1));\n\n\t\t\t\treportTypeMismatch({\n\t\t\t\t\tmessageId: 'incorrectTwoslashType',\n\t\t\t\t\tcontext,\n\t\t\t\t\tstart,\n\t\t\t\t\tend,\n\t\t\t\t\tdata: {expectedComment, actualComment},\n\t\t\t\t\tfix: expectedComment.replaceAll('\\n', `\\n${indent}`),\n\t\t\t\t});\n\t\t\t}\n\t\t}\n\t}\n}\n" }, { "path": "lint-rules/validate-jsdoc-codeblocks.test.js", "content": "/* eslint-disable max-lines */\nimport {code1, code2, createRuleTester, dedenter, errorAt as errorAt_, exportType, exportTypeAndOption, fence, jsdoc} from './test-utils.js';\nimport {validateJSDocCodeblocksRule} from './validate-jsdoc-codeblocks.js';\n\nconst ruleTester = createRuleTester();\n\nconst codeWithErrors = dedenter`\nimport type {RemovePrefix} from 'type-fest';\n\ntype A = RemovePrefix<'on-change', string, {strict: \"yes\"}>;\n`;\n\nconst invalidCodeblockErrorAt = props => errorAt_({...props, messageId: 'invalidCodeblock'});\nconst incorrectTwoslashTypeErrorAt = props => errorAt_({...props, messageId: 'incorrectTwoslashType'});\nconst incorrectTwoslashFormatErrorAt = props => errorAt_({...props, messageId: 'incorrectTwoslashFormat'});\n\nruleTester.run('validate-jsdoc-codeblocks', validateJSDocCodeblocksRule, {\n\tvalid: [\n\t\t// Not exported\n\t\tdedenter`\n\t\t\t${jsdoc(fence(codeWithErrors))}\n\t\t\ttype NotExported = string;\n\t\t`,\n\t\tdedenter`\n\t\t\ttype NotExportedOptions = {\n\t\t\t\t${jsdoc(fence(codeWithErrors))}\n\t\t\t\tp1: string;\n\t\t\t}\n\t\t`,\n\n\t\t// Internal (leading underscore)\n\t\tdedenter`\n\t\t\t${jsdoc(fence(codeWithErrors))}\n\t\t\texport type _Internal = string;\n\t\t`,\n\t\tdedenter`\n\t\t\texport type _InternalOptions = {\n\t\t\t\t${jsdoc(fence(codeWithErrors))}\n\t\t\t\tp1: string;\n\t\t\t}\n\t\t`,\n\n\t\t// Without `Options` suffix\n\t\tdedenter`\n\t\t\texport type NoSuffix = {\n\t\t\t\t${jsdoc(fence(codeWithErrors))}\n\t\t\t\tp1: string;\n\t\t\t}\n\t\t`,\n\n\t\t// No JSDoc\n\t\texportTypeAndOption(''),\n\t\texportType('type Some = number;'),\n\t\texportTypeAndOption('// Not block comment'),\n\t\texportTypeAndOption('/* Block comment, but not JSDoc */'),\n\n\t\t// No codeblock in JSDoc\n\t\texportType(jsdoc('No codeblock here')),\n\n\t\t// With text before and after\n\t\texportTypeAndOption(jsdoc('Some description.', fence(code1), '@category Test')),\n\n\t\t// With line breaks before and after\n\t\texportTypeAndOption(\n\t\t\tjsdoc('Some description.\\n', 'Note: Some note.\\n', fence(code1, 'ts'), '\\n@category Test'),\n\t\t),\n\n\t\t// With `@example` tag\n\t\texportTypeAndOption(jsdoc('@example', fence(code1))),\n\n\t\t// With language specifiers\n\t\texportTypeAndOption(jsdoc(fence(code1, 'ts'))),\n\t\texportTypeAndOption(jsdoc(fence(code1, 'typescript'))),\n\n\t\t// Multiple code blocks\n\t\texportTypeAndOption(\n\t\t\tjsdoc('@example', fence(code1, 'ts'), '\\nSome text in between.\\n', '@example', fence(code2)),\n\t\t),\n\n\t\t// Multiple exports and multiple properties\n\t\texportTypeAndOption(jsdoc(fence(code1)), jsdoc(fence(code2))),\n\n\t\t// With @ts-expect-error\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\timport type {ExtractStrict} from 'type-fest';\n\n\t\t\t// @ts-expect-error\n\t\t\ttype A = ExtractStrict<'foo' | 'bar', 'baz'>;\n\t\t`))),\n\n\t\t// Indented code blocks\n\t\texportTypeAndOption(jsdoc(\n\t\t\t'Note:',\n\t\t\tdedenter`\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {Subtract} from 'type-fest';\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {Sum} from 'type-fest';\n\t\t\t\t\ttype A = Sum<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t`,\n\t\t)),\n\n\t\t// Compiler options overrides\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\t// @exactOptionalPropertyTypes: false\n\t\t\tconst foo: {a?: number} = {a: undefined};\n\t\t`))),\n\n\t\t// Incorrect compiler options are ignored\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\t// @noUnusedLocals: 'invalid-value'\n\t\t\tconst foo = {a: 1};\n\t\t`))),\n\n\t\t// Line comment between JSDoc and type/option\n\t\texportTypeAndOption(dedenter`\n\t\t\t${jsdoc(fence(code1))}\n\t\t\t// Some line comment between JSDoc and export\n\t\t`),\n\t],\n\tinvalid: [\n\t\t// With text before and after\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\tSome description.\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\texport type TOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\tSome description.\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t@category Test\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 4, textBeforeStart: 'type A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 14, textBeforeStart: '\\ttype A = ', target: 'Subtract'}),\n\t\t\t],\n\t\t},\n\n\t\t// With line breaks before and after\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\tSome description.\n\n\t\t\t\tNote: Some note.\n\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\\`\\`\\`\n\n\t\t\t\t@category Test\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\texport type TOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\tSome description.\n\n\t\t\t\t\tNote: Some note.\n\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\n\t\t\t\t\t@category Test\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 7, textBeforeStart: 'type A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 21, textBeforeStart: '\\ttype A = ', target: 'Subtract'}),\n\t\t\t],\n\t\t},\n\n\t\t// With `@example` tag\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\texport type TOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\t@example\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 4, textBeforeStart: 'type A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 13, textBeforeStart: '\\ttype A = ', target: 'Subtract'}),\n\t\t\t],\n\t\t},\n\n\t\t// With language specifiers\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\texport type TOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 3, textBeforeStart: 'type A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 11, textBeforeStart: '\\ttype A = ', target: 'Subtract'}),\n\t\t\t],\n\t\t},\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`typescript\n\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\texport type TOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\t\\`\\`\\`typescript\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 3, textBeforeStart: 'type A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 11, textBeforeStart: '\\ttype A = ', target: 'Subtract'}),\n\t\t\t],\n\t\t},\n\n\t\t// Multiple code blocks\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\\`\\`\\`\n\n\t\t\t\tSome text in between.\n\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\timport type {ExcludeStrict} from 'type-fest';\n\n\t\t\t\ttype A = ExcludeStrict;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\texport type TOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\t@example\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\n\t\t\t\t\tSome text in between.\n\n\t\t\t\t\t@example\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {ExcludeStrict} from 'type-fest';\n\n\t\t\t\t\ttype A = ExcludeStrict;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 4, textBeforeStart: 'type A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 13, textBeforeStart: 'type A = ExcludeStrict;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\timport type {ExcludeStrict} from 'type-fest';\n\n\t\t\t\ttype A = ExcludeStrict;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T1 = string;\n\n\t\t\t\texport type T0Options = {\n\t\t\t\t\t/**\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\n\t\t\t\t\t/**\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {ExcludeStrict} from 'type-fest';\n\n\t\t\t\t\ttype A = ExcludeStrict;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp1: string;\n\t\t\t\t};\n\n\t\t\t\texport type T1Options = {\n\t\t\t\t\t/**\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {Sum} from 'type-fest';\n\n\t\t\t\t\tSum<1, 2>; //=> 3\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 3, textBeforeStart: 'type A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 12, textBeforeStart: 'type A = ExcludeStrict;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\ttype A = Sum<1, 2>;\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\n\t\t\t\texport type TOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\tNote:\n\t\t\t\t\t1. First point\n\t\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t2. Second point\n\t\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\t\ttype A = Sum<1, 2>;\n\t\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t*/\n\t\t\t\t\tp0: string;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 5, textBeforeStart: '\\ttype A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 9, textBeforeStart: '\\ttype A = ', target: 'Sum'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 19, textBeforeStart: '\\t\\ttype A = ', target: 'Subtract'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 23, textBeforeStart: '\\t\\ttype A = ', target: 'Sum'}),\n\t\t\t],\n\t\t},\n\n\t\t// Missing import\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\tDescription\n\t\t\t\t\\`\\`\\`\n\t\t\t\ttype A = Sum<1, 2>;\n\t\t\t\t//=> 3\n\n\t\t\t\ttype B = Sum<-1, 2>;\n\t\t\t\t//=> 1\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type Sum = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 4, textBeforeStart: 'type A = ', target: 'Sum'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 7, textBeforeStart: 'type B = ', target: 'Sum'}),\n\t\t\t],\n\t\t},\n\n\t\t// Floating examples\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\timport type {IsUppercase} from 'type-fest';\n\n\t\t\tIsUppercase<'ABC'>;\n\t\t\t//=> true\n\n\t\t\tIsUppercase<'Abc'>;\n\t\t\t//=> false\n\t\t\t\\`\\`\\`\n\t\t\t@category Utilities\n\t\t\t*/\n\t\t\texport type IsUppercase = boolean;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 5, textBeforeStart: '', target: 'IsUppercase'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 8, textBeforeStart: '', target: 'IsUppercase'}),\n\t\t\t],\n\t\t},\n\n\t\t// Hypthetical references\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\tSome description\n\t\t\t\tSome note\n\t\t\t\t\\`\\`\\`\n\t\t\t\timport type {Except} from 'type-fest';\n\n\t\t\t\ttype PostPayload = Except;\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type Except = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 7, textBeforeStart: 'type PostPayload = Except<', target: 'UserData'}),\n\t\t\t],\n\t\t},\n\n\t\t// Duplicate identifiers\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\texport type IsTupleOptions = {\n\t\t\t\t\t/**\n\t\t\t\t\t@example\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\timport type {IsTuple} from 'type-fest';\n\n\t\t\t\t\ttype Example = IsTuple<[number, ...number[]], {fixedLengthOnly: true}>;\n\t\t\t\t\t//=> false\n\n\t\t\t\t\ttype Example = IsTuple<[number, ...number[]], {fixedLengthOnly: false}>;\n\t\t\t\t\t//=> true\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t\t@default true\n\t\t\t\t\t*/\n\t\t\t\t\tfixedLengthOnly: boolean;\n\t\t\t\t};\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 7, textBeforeStart: '\\ttype ', target: 'Example'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 10, textBeforeStart: '\\ttype ', target: 'Example'}),\n\t\t\t],\n\t\t},\n\n\t\t// Multi line error\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t@example\n\t\t\t\t\\`\\`\\`\n\t\t\t\tdeclare function updateConfig(newConfig: {name?: string; version?: number}): void;\n\n\t\t\t\tupdateConfig({\n\t\t\t\t\tname: undefined,\n\t\t\t\t\tversion: undefined,\n\t\t\t\t});\n\t\t\t\t\\`\\`\\`\n\t\t\t\t@category Utilities\n\t\t\t\t*/\n\t\t\t\texport type MultiLine = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 6, textBeforeStart: 'updateConfig(', endLine: 9, textBeforeEnd: '}'}),\n\t\t\t],\n\t\t},\n\n\t\t// Precise one character error\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`\n\t\t\timport type {ExcludeStrict} from 'type-fest';\n\n\t\t\ttype A = ExcludeStrict<'a' | 'b', 'A'>;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type ExcludeStrict = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({\n\t\t\t\t\tline: 5,\n\t\t\t\t\ttextBeforeStart: 'type A = ExcludeStrict<\\'a\\' | \\'b\\', ',\n\t\t\t\t\ttarget: '\\'A\\'',\n\t\t\t\t}),\n\t\t\t],\n\t\t},\n\n\t\t// `exactOptionalPropertyTypes` is enabled\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`\n\t\t\tconst test: {foo?: string} = {foo: undefined};\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type Test = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 3, textBeforeStart: 'const ', target: 'test'}),\n\t\t\t],\n\t\t},\n\n\t\t// Overlapping errors\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`typescript\n\t\t\timport type {ExcludeStrict, Sum} from 'type-fest';\n\n\t\t\ttype A = Sum<1, '2'>;\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type Test = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 5, textBeforeStart: 'type A = ', target: 'Sum<1, \\'2\\'>'}),\n\t\t\t\tinvalidCodeblockErrorAt({line: 5, textBeforeStart: 'type A = Sum<1, ', target: '\\'2\\''}),\n\t\t\t],\n\t\t},\n\n\t\t// Compiler options overrides\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t/**\n\t\t\t\\`\\`\\`ts\n\t\t\t// @noUnusedLocals: true\n\t\t\tconst foo = {a: 1};\n\t\t\t\\`\\`\\`\n\t\t\t*/\n\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tinvalidCodeblockErrorAt({line: 4, textBeforeStart: 'const ', target: 'foo'}),\n\t\t\t],\n\t\t},\n\t],\n});\n\n// Type mismatch tests\nruleTester.run('validate-jsdoc-codeblocks', validateJSDocCodeblocksRule, {\n\tvalid: [\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Foo = string;\n\t\t\t//=> string\n\t\t`))),\n\n\t\t// No twoslash comment at all\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst foo = 'bar';\n\t\t`))),\n\n\t\t// Twoslash comment at very first line\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\t//=> 'bar'\n\t\t\tconst foo = 'bar';\n\t\t`))),\n\n\t\t// Object type collapsed into single line\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst foo = {a: 1, b: {c: 'c'}};\n\t\t\t//=> {a: number; b: {c: string}}\n\t\t`))),\n\n\t\t// Multiline type\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\timport type {Simplify} from 'type-fest';\n\n\t\t\ttype Foo = {readonly a: number; readonly b?: number};\n\t\t\ttype Bar = {c?: string; d: {readonly e: boolean}; e: string};\n\t\t\ttype Baz = Simplify;\n\t\t\t//=> {\n\t\t\t// \treadonly a: number;\n\t\t\t// \treadonly b?: number;\n\t\t\t// \tc?: string;\n\t\t\t// \td: {\n\t\t\t// \t\treadonly e: boolean;\n\t\t\t// \t};\n\t\t\t// \te: string;\n\t\t\t// }\n\t\t`))),\n\n\t\t// Quick info at 0th index\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tlet foo = 1;\n\t\t\tfoo++;\n\t\t\t//=> number\n\t\t`))),\n\n\t\t// Quick info at some middle index\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst foo = 1 as string | number;\n\t\t\t//=> string | number\n\t\t`))),\n\n\t\t// Quick info at last index\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst foo = {n: 1}\n\t\t\tconst bar = foo\n\t\t\t\t.n\n\t\t\t//=> number\n\t\t`))),\n\n\t\t// Double-quotes properly replaced\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\timport type {Simplify} from 'type-fest';\n\n\t\t\ttype Foo = {a: 'abc'; b: 123; c: 'def'};\n\t\t\ttype Bar = {x: {y: 'y'; z: 'z'}};\n\t\t\ttype Baz = Simplify;\n\t\t\t//=> {a: 'abc'; b: 123; c: 'def'; x: {y: 'y'; z: 'z'}}\n\t\t`))),\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Foo = 'a\"b\"c';\n\t\t\t//=> 'a\"b\"c'\n\n\t\t\ttype Bar = \"d'e'f\";\n\t\t\t//=> 'd\\'e\\'f'\n\t\t`))),\n\n\t\t// Space indentation properly replaced\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\timport type {Simplify} from 'type-fest';\n\n\t\t\ttype Foo = {\n\t\t\t\ta: {\n\t\t\t\t\tab: boolean;\n\t\t\t\t\tac: {\n\t\t\t\t\t\tacd: string | number;\n\t\t\t\t\t};\n\t\t\t\t};\n\t\t\t\te: [\n\t\t\t\t\t{\n\t\t\t\t\t\tfgh: false;\n\t\t\t\t\t\tijk: {\n\t\t\t\t\t\t\tlmno: 'yes' | 'no';\n\t\t\t\t\t\t};\n\t\t\t\t\t},\n\t\t\t\t\tstring,\n\t\t\t\t\t[\n\t\t\t\t\t\t'foo',\n\t\t\t\t\t\t'bar',\n\t\t\t\t\t],\n\t\t\t\t];\n\t\t\t};\n\n\t\t\ttype Bar = Simplify;\n\t\t\t//=> {\n\t\t\t// \ta: {\n\t\t\t// \t\tab: boolean;\n\t\t\t// \t\tac: {\n\t\t\t// \t\t\tacd: string | number;\n\t\t\t// \t\t};\n\t\t\t// \t};\n\t\t\t// \te: [{\n\t\t\t// \t\tfgh: false;\n\t\t\t// \t\tijk: {\n\t\t\t// \t\t\tlmno: 'yes' | 'no';\n\t\t\t// \t\t};\n\t\t\t// \t}, string, ['foo', 'bar']];\n\t\t\t// }\n\t\t`))),\n\n\t\t// Compiler options overrides\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\t// @exactOptionalPropertyTypes: false\n\t\t\timport type {AllExtend} from 'type-fest';\n\n\t\t\ttype A = AllExtend<[1?, 2?, 3?], number>;\n\t\t\t//=> boolean\n\t\t`))),\n\n\t\t// Multiple `//=>`\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst foo = {a: true, b: false, c: {d: true}} as const;\n\t\t\t//=> {\n\t\t\t// \treadonly a: true;\n\t\t\t// \treadonly b: false;\n\t\t\t// \treadonly c: {\n\t\t\t// \t\treadonly d: true;\n\t\t\t// \t};\n\t\t\t// }\n\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t//=> readonly ['a', 'b', 'c']\n\t\t\tconst baz = new Set(bar);\n\t\t\t//=> Set<'a' | 'b' | 'c'>\n\t\t`))),\n\n\t\t// Indented code blocks\n\t\texportTypeAndOption(jsdoc(\n\t\t\t'Note:',\n\t\t\tdedenter`\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {Subtract} from 'type-fest';\n\t\t\t\t\ttype A = Subtract<1, 2>;\n\t\t\t\t\t//=> -1\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\timport type {Sum} from 'type-fest';\n\t\t\t\t\ttype A = Sum<1, 2>;\n\t\t\t\t\t//=> 3\n\t\t\t\t\t\\`\\`\\`\n\t\t\t`,\n\t\t)),\n\n\t\t// Order of non-numbers in unions doesn't matter\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Test = 'a' | 'b' | {x: ['c' | 'd' | 'e']; y: {z: 'f' | 'g' | 'h'}};\n\n\t\t\ttype Valid = Test\n\t\t\t//=> 'b' | 'a' | {x: ['d' | 'c' | 'e']; y: {z: 'g' | 'h' | 'f'}}\n\t\t\t\n\t\t\ttype Valid2 = Test\n\t\t\t//=> 'a' | {x: ['e' | 'd' | 'c']; y: {z: 'h' | 'g' | 'f'}} | 'b'\n\t\t\t\n\t\t\ttype Valid3 = Test\n\t\t\t//=> {x: ['e' | 'c' | 'd']; y: {z: 'h' | 'f' | 'g'}} | 'b' | 'a'\n\t\t`))),\n\n\t\t// Numbers are sorted in unions\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\timport type {IntClosedRange} from 'type-fest';\n\n\t\t\ttype ZeroToNine = IntClosedRange<0, 9>;\n\t\t\t//=> 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9\n\t\t`))),\n\n\t\t// Numbers in nested unions are sorted\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Test = {w: 0 | 10 | 5; x: [2 | 16 | 4]; y: {z: 3 | 27 | 9}};\n\t\t\t//=> {w: 0 | 5 | 10; x: [2 | 4 | 16]; y: {z: 3 | 9 | 27}}\n\t\t`))),\n\n\t\t// Numbers in unions inside unions are sorted, non-numbers can be in any order\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Test = {a: 'foo' | 27 | 1 | {b: 2 | 1 | 8 | 4} | 'baz' | 9 | 3 | 'bar'};\n\n\t\t\ttype Valid = Test;\n\t\t\t//=> {a: 1 | 3 | 9 | 27 | {b: 1 | 2 | 4 | 8} | 'bar' | 'foo' | 'baz'}\n\t\t\t\n\t\t\ttype Valid2 = Test;\n\t\t\t//=> {a: {b: 1 | 2 | 4 | 8} | 1 | 'foo' | 3 | 'baz' | 'bar' | 9 | 27}\n\t\t\t\n\t\t\ttype Valid3 = Test;\n\t\t\t//=> {a: 'baz' | 'foo' | 1 | 3 | 9 | 'bar' | 27 | {b: 1 | 2 | 4 | 8}}\n\t\t`))),\n\n\t\t// Only numbers are sorted in unions, non-numbers can be in any order\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\timport type {ArrayElement} from 'type-fest';\n\n\t\t\ttype Tuple1 = ArrayElement<[null, string, boolean, 1, 3, 0, -2, 4, 2, -1]>;\n\t\t\t//=> string | -2 | -1 | boolean | 0 | null | 1 | 2 | 3 | 4\n\n\t\t\ttype Tuple2 = ArrayElement<[null, 1, 3, string, 0, -2, 4, 2, boolean, -1]>;\n\t\t\t//=> -2 | boolean | -1 | 0 | 1 | 2 | 3 | 4 | null | string\n\t\t`))),\n\n\t\t// Tuples are in single line\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\timport type {TupleOf} from 'type-fest';\n\n\t\t\ttype RGB = TupleOf<3, number>;\n\t\t\t//=> [number, number, number]\n\n\t\t\ttype TicTacToeBoard = TupleOf<3, TupleOf<3, 'X' | 'O' | null>>;\n\t\t\t//=> [['X' | 'O' | null, 'X' | 'O' | null, 'X' | 'O' | null], ['X' | 'O' | null, 'X' | 'O' | null, 'X' | 'O' | null], ['X' | 'O' | null, 'X' | 'O' | null, 'X' | 'O' | null]]\n\t\t`))),\n\n\t\t// Emojis are preserved\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Pets = '🦄' | '🐶' | '🐇';\n\t\t\t//=> '🦄' | '🐶' | '🐇'\n\t\t`))),\n\n\t\t// `0` and `Infinity` verbosity levels\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Test = {a: Pick<{b: Pick<{c: Pick<{d: 1}, 'd'>}, 'c'>}, 'b'>};\n\n\t\t\ttype LevelZero = Test;\n\t\t\t//=> {a: {b: {c: {d: 1}}}}\n\n\t\t\ttype LevelThree = Test;\n\t\t\t//=> {\n\t\t\t// \ta: Pick<{\n\t\t\t// \t\tb: Pick<{\n\t\t\t// \t\t\tc: Pick<{\n\t\t\t// \t\t\t\td: 1;\n\t\t\t// \t\t\t}, 'd'>;\n\t\t\t// \t\t}, 'c'>;\n\t\t\t// \t}, 'b'>;\n\t\t\t// }\n\t\t`))),\n\n\t\t// Custom verbosity level\n\t\t// `0` and `Infinity` verbosity levels are still allowed\n\t\t{\n\t\t\tcode: exportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\t\ttype Test = {a: Pick<{b: Pick<{c: Pick<{d: 1}, 'd'>}, 'c'>}, 'b'>};\n\n\t\t\t\ttype LevelZero = Test;\n\t\t\t\t//=> {a: {b: {c: {d: 1}}}}\n\n\t\t\t\ttype LevelOne = Test;\n\t\t\t\t//=> {a: {b: Pick<{c: Pick<{d: 1}, 'd'>}, 'c'>}}\n\n\t\t\t\ttype LevelTwo = Test;\n\t\t\t\t//=> {a: {b: {c: Pick<{d: 1}, 'd'>}}}\n\n\t\t\t\ttype LevelThree = Test;\n\t\t\t\t//=> {\n\t\t\t\t// \ta: Pick<{\n\t\t\t\t// \t\tb: Pick<{\n\t\t\t\t// \t\t\tc: Pick<{\n\t\t\t\t// \t\t\t\td: 1;\n\t\t\t\t// \t\t\t}, 'd'>;\n\t\t\t\t// \t\t}, 'c'>;\n\t\t\t\t// \t}, 'b'>;\n\t\t\t\t// }\n\t\t\t`))),\n\t\t\toptions: [{verbosityLevels: [1, 2]}],\n\t\t},\n\n\t\t// === Different types of quick info ===\n\t\t// Function\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tdeclare function foo(a: string): {b: string; c: number};\n\t\t\tfoo('a');\n\t\t\t//=> {b: string; c: number}\n\t\t`))),\n\n\t\t// Variable\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst foo = 'foo';\n\t\t\t//=> 'foo'\n\n\t\t\tlet bar = {a: 1};\n\t\t\t//=> {a: number}\n\n\t\t\tvar baz = true;\n\t\t\t//=> boolean\n\t\t`))),\n\n\t\t// Type Alias\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\ttype Foo = {a: number};\n\t\t\t//=> {a: number}\n\t\t`))),\n\n\t\t// Interface\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tinterface Foo { foo: string; }\n\t\t\t//=> Foo\n\t\t`))),\n\n\t\t// Generic interface\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tinterface Foo { foo: T; }\n\t\t\t//=> Foo\n\t\t`))),\n\n\t\t// Parameter\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tfunction foo(n: number) {\n\t\t\t\tn++;\n\t\t\t\t//=> number\n\t\t\t}\n\t\t`))),\n\n\t\t// Property\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst foo = {n: 1};\n\t\t\tfoo\n\t\t\t\t.n++;\n\t\t\t//=> number\n\t\t`))),\n\n\t\t// Method\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tclass Foo {\n\t\t\t\tm() {\n\t\t\t\t\treturn 'foo';\n\t\t\t\t}\n\t\t\t}\n\n\t\t\tconst f = new Foo()\n\t\t\t\t.m();\n\t\t\t//=> string\n\t\t`))),\n\n\t\t// Constructor\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tclass Foo {\n\t\t\t\tconstructor() {\n\t\t\t\t\t//=> Foo\n\t\t\t\t\tconsole.log('Foo');\n\t\t\t\t}\n\t\t\t}\n\t\t`))),\n\n\t\t// Enum\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tenum Foo {}\n\t\t\t//=> Foo\n\t\t`))),\n\n\t\t// Const enum\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tconst enum Foo { A = 1 }\n\t\t\t//=> Foo\n\t\t`))),\n\n\t\t// Enum Member\n\t\texportTypeAndOption(jsdoc(fence(dedenter`\n\t\t\tenum Foo { A }\n\t\t\tvoid Foo\n\t\t\t.A;\n\t\t\t//=> 0\n\t\t`))),\n\t],\n\tinvalid: [\n\t\t// === Twoslash format errors ===\n\n\t\t// No space after `//=>`\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = string;\n\t\t\t\t//=>string\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4,\ttextBeforeStart: '',\ttarget: '//=>string'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = string;\n\t\t\t\t//=> string\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// More than one space after `//=>`\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = string;\n\t\t\t\t//=> string\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', target: '//=> string'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = string;\n\t\t\t\t//=> string\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Incorrect spacing\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = 'a' | 'b' | { c: 'd' } | 'e';\n\t\t\t\t//=> 'a'|'b' | { c : 'd' }| 'e' \n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', target: '//=> \\'a\\'|\\'b\\' | { c : \\'d\\' }| \\'e\\' '}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = 'a' | 'b' | { c: 'd' } | 'e';\n\t\t\t\t//=> 'a' | 'b' | {c: 'd'} | 'e'\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// No space in subsequent lines\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: true, b: true, c: false, d: false, e: true} as const;\n\t\t\t\t//=> {\n\t\t\t\t//\treadonly a: true;\n\t\t\t\t//\treadonly b: true;\n\t\t\t\t//\treadonly c: false;\n\t\t\t\t//\treadonly d: false;\n\t\t\t\t//\treadonly e: true;\n\t\t\t\t//}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', endLine: 10, textBeforeEnd: '//}'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: true, b: true, c: false, d: false, e: true} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly a: true;\n\t\t\t\t// \treadonly b: true;\n\t\t\t\t// \treadonly c: false;\n\t\t\t\t// \treadonly d: false;\n\t\t\t\t// \treadonly e: true;\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Incorrect double quotes\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = [\"a\", {b: \"c\", d: {e: \"f\"}}, \"g\" | \"h\"];\n\t\t\t\t//=> [\"a\", {b: \"c\"; d: {e: \"f\"}}, \"g\" | \"h\"]\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', target: '//=> [\"a\", {b: \"c\"; d: {e: \"f\"}}, \"g\" | \"h\"]'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = [\"a\", {b: \"c\", d: {e: \"f\"}}, \"g\" | \"h\"];\n\t\t\t\t//=> ['a', {b: 'c'; d: {e: 'f'}}, 'g' | 'h']\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Incorrect multiline tuples\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\timport type {TupleOf} from 'type-fest';\n\n\t\t\t\ttype RGB = TupleOf<3, number>;\n\t\t\t\t//=> [\n\t\t\t\t// \tnumber,\n\t\t\t\t// \tnumber,\n\t\t\t\t// \tnumber,\n\t\t\t\t// ]\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 6, textBeforeStart: '', endLine: 10, textBeforeEnd: '// ]'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\timport type {TupleOf} from 'type-fest';\n\n\t\t\t\ttype RGB = TupleOf<3, number>;\n\t\t\t\t//=> [number, number, number]\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Multi line to single line\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = [{a: 1}] as const;\n\t\t\t\t//=> readonly [{\n\t\t\t\t// \treadonly a: 1;\n\t\t\t\t// }]\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', endLine: 6, textBeforeEnd: '// }]'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = [{a: 1}] as const;\n\t\t\t\t//=> readonly [{readonly a: 1}]\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Single line to multi line\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: true, b: true, c: false, d: false, e: true} as const;\n\t\t\t\t//=> {readonly a: true; readonly b: true; readonly c: false; readonly d: false; readonly e: true}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', target: '//=> {readonly a: true; readonly b: true; readonly c: false; readonly d: false; readonly e: true}'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: true, b: true, c: false, d: false, e: true} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly a: true;\n\t\t\t\t// \treadonly b: true;\n\t\t\t\t// \treadonly c: false;\n\t\t\t\t// \treadonly d: false;\n\t\t\t\t// \treadonly e: true;\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Incorrect order of numbers in unions\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype T1 = 5 | 4 | 3 | 2 | 1;\n\t\t\t\t//=> 5 | 4 | 1 | 2 | 3\n\n\t\t\t\ttype T2 = 1 | 2 | 3 | 'a';\n\t\t\t\t//=> 2 | 'a' | 3 | 1\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', target: '//=> 5 | 4 | 1 | 2 | 3'}),\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 7, textBeforeStart: '', target: '//=> 2 | \\'a\\' | 3 | 1'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype T1 = 5 | 4 | 3 | 2 | 1;\n\t\t\t\t//=> 1 | 2 | 3 | 4 | 5\n\n\t\t\t\ttype T2 = 1 | 2 | 3 | 'a';\n\t\t\t\t//=> 1 | 'a' | 2 | 3\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Indented code blocks\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\tNote:\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst foo = {a: true, b: false, c: {d: true}};\n\t\t\t\t\t//=> {a: boolean; b: boolean;\n\t\t\t\t\t// c: {d: boolean};\n\t\t\t\t\t// }\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t\t//=> readonly [ 'a', 'b', 'c' ]\n\t\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t\t//=>Set< 'a'|'b'|'c' >\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 6, textBeforeStart: '\\t', endLine: 8, textBeforeEnd: '\\t// }'}),\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 13, textBeforeStart: '\\t', target: '//=> readonly [ \\'a\\', \\'b\\', \\'c\\' ]'}),\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 15, textBeforeStart: '\\t', target: '//=>Set< \\'a\\'|\\'b\\'|\\'c\\' >'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\tNote:\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst foo = {a: true, b: false, c: {d: true}};\n\t\t\t\t\t//=> {a: boolean; b: boolean; c: {d: boolean}}\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t\t//=> readonly ['a', 'b', 'c']\n\t\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t\t//=> Set<'a' | 'b' | 'c'>\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Multiple `//=>`\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: 'a', b: 'b'} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly a: 'a';\n\t\t\t\t// \treadonly b: 'b';\n\t\t\t\t// }\n\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t//=> readonly [\n\t\t\t\t// \t'a', \n\t\t\t\t// \t'b', \n\t\t\t\t// \t'c'\n\t\t\t\t// ]\n\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t//=> Set<\n\t\t\t\t// \t| 'a'\n\t\t\t\t// \t| 'b'\n\t\t\t\t// \t| 'c'\n\t\t\t\t// >\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 4, textBeforeStart: '', endLine: 7, textBeforeEnd: '// }'}),\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 9, textBeforeStart: '', endLine: 13, textBeforeEnd: '// ]'}),\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 15, textBeforeStart: '', endLine: 19, textBeforeEnd: '// >'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: 'a', b: 'b'} as const;\n\t\t\t\t//=> {readonly a: 'a'; readonly b: 'b'}\n\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t//=> readonly ['a', 'b', 'c']\n\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t//=> Set<'a' | 'b' | 'c'>\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Preserves the specified verbosity level during formatting fixes\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = {a: Pick<{b: Pick<{c: Pick<{d: 'abracadabra'}, 'd'>}, 'c'>}, 'b'>};\n\n\t\t\t\ttype LevelOne = Test;\n\t\t\t\t//=> {a: {b: Pick<{c: Pick<{d: 'abracadabra'}, 'd'>}, 'c'>}}\n\n\t\t\t\ttype LevelTwo = Test;\n\t\t\t\t//=> {a: {b: {c: Pick<{d: \"abracadabra\"}, \"d\">}}}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 6, textBeforeStart: '', target: '//=> {a: {b: Pick<{c: Pick<{d: \\'abracadabra\\'}, \\'d\\'>}, \\'c\\'>}}'}),\n\t\t\t\tincorrectTwoslashFormatErrorAt({line: 9, textBeforeStart: '', target: '//=> {a: {b: {c: Pick<{d: \"abracadabra\"}, \"d\">}}}'}),\n\t\t\t],\n\t\t\toptions: [{verbosityLevels: [1, 2]}],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = {a: Pick<{b: Pick<{c: Pick<{d: 'abracadabra'}, 'd'>}, 'c'>}, 'b'>};\n\n\t\t\t\ttype LevelOne = Test;\n\t\t\t\t//=> {\n\t\t\t\t// \ta: {\n\t\t\t\t// \t\tb: Pick<{\n\t\t\t\t// \t\t\tc: Pick<{\n\t\t\t\t// \t\t\t\td: 'abracadabra';\n\t\t\t\t// \t\t\t}, 'd'>;\n\t\t\t\t// \t\t}, 'c'>;\n\t\t\t\t// \t};\n\t\t\t\t// }\n\n\t\t\t\ttype LevelTwo = Test;\n\t\t\t\t//=> {a: {b: {c: Pick<{d: 'abracadabra'}, 'd'>}}}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// === Twoslash type errors ===\n\n\t\t// Incorrect type\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = 'bar';\n\t\t\t\t//=> 'baz'\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', target: '//=> \\'baz\\''}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = 'bar';\n\t\t\t\t//=> 'bar'\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Empty `//=>`\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = string;\n\t\t\t\t//=>\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', target: '//=>'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Foo = string;\n\t\t\t\t//=> string\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Broken type\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: 1, b: 2};\n\t\t\t\t//=> {a\n\t\t\t\t\n\t\t\t\tconst bar = {a: 1, b: 2};\n\t\t\t\t//=> {a: number\n\t\t\t\t// \tb:\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', target: '//=> {a'}),\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 7, textBeforeStart: '', endLine: 8, textBeforeEnd: '// \tb:'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: 1, b: 2};\n\t\t\t\t//=> {a: number; b: number}\n\n\t\t\t\tconst bar = {a: 1, b: 2};\n\t\t\t\t//=> {a: number; b: number}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Multiline replace\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {foo: true, bar: {baz: true, qux: [true, false]}} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \tfoo: true;\n\t\t\t\t// \treadonly bar: {\n\t\t\t\t// \t\treadonly baz: false;\n\t\t\t\t// \t\treadonly qux: [true, false];\n\t\t\t\t// \t};\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', endLine: 10, textBeforeEnd: '// }'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {foo: true, bar: {baz: true, qux: [true, false]}} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly foo: true;\n\t\t\t\t// \treadonly bar: {\n\t\t\t\t// \t\treadonly baz: true;\n\t\t\t\t// \t\treadonly qux: readonly [true, false];\n\t\t\t\t// \t};\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Multiline add missing lines\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {foo: true, bar: {baz: true, qux: [true, false]}} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly bar: {\n\t\t\t\t// \t\treadonly qux: readonly [true, false];\n\t\t\t\t// \t};\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', endLine: 8, textBeforeEnd: '// }'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {foo: true, bar: {baz: true, qux: [true, false]}} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly foo: true;\n\t\t\t\t// \treadonly bar: {\n\t\t\t\t// \t\treadonly baz: true;\n\t\t\t\t// \t\treadonly qux: readonly [true, false];\n\t\t\t\t// \t};\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Multiline remove extra lines\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {bar: {qux: [true, false]}, quux: [null, undefined]} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly foo: true;\n\t\t\t\t// \treadonly bar: {\n\t\t\t\t// \t\treadonly baz: true;\n\t\t\t\t// \t\treadonly qux: readonly [true, false];\n\t\t\t\t// \t};\n\t\t\t\t// \treadonly quux: readonly [null, undefined];\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', endLine: 11, textBeforeEnd: '// }'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {bar: {qux: [true, false]}, quux: [null, undefined]} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly bar: {\n\t\t\t\t// \t\treadonly qux: readonly [true, false];\n\t\t\t\t// \t};\n\t\t\t\t// \treadonly quux: readonly [null, undefined];\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Compiler options overrides\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\t// @exactOptionalPropertyTypes: false\n\t\t\t\ttype Prettify = {\n\t\t\t\t\t[P in keyof T]: T[P];\n\t\t\t\t};\n\n\t\t\t\ttype T1 = Prettify<{a?: string; b?: number}>;\n\t\t\t\t//=> {\n\t\t\t\t// \ta?: string;\n\t\t\t\t// \tb?: number;\n\t\t\t\t// }\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 9, textBeforeStart: '', endLine: 12, textBeforeEnd: '// }'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\t// @exactOptionalPropertyTypes: false\n\t\t\t\ttype Prettify = {\n\t\t\t\t\t[P in keyof T]: T[P];\n\t\t\t\t};\n\n\t\t\t\ttype T1 = Prettify<{a?: string; b?: number}>;\n\t\t\t\t//=> {a?: string | undefined; b?: number | undefined}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Incorrect type and improper formatting\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: 'a', b: 'b'} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \ta: 'a';\n\t\t\t\t// \tb: 'b';\n\t\t\t\t// }\n\n\t\t\t\tconst bar = 'bar';\n\t\t\t\t//=>\"baz\"\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', endLine: 7, textBeforeEnd: '// }'}),\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 10, textBeforeStart: '', target: '//=>\"baz\"'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: 'a', b: 'b'} as const;\n\t\t\t\t//=> {readonly a: 'a'; readonly b: 'b'}\n\n\t\t\t\tconst bar = 'bar';\n\t\t\t\t//=> 'bar'\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Indented code blocks\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\tNote:\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst foo = {a: true, b: false, c: {d: true}} as const;\n\t\t\t\t\t//=> {\n\t\t\t\t\t// \ta?: false;\n\t\t\t\t\t// \tc?: {\n\t\t\t\t\t// \t\td?: false;\n\t\t\t\t\t// \t};\n\t\t\t\t\t// }\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t\t//=> ['a', 'c']\n\t\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t\t//=> Set\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 6, textBeforeStart: '\\t', endLine: 11, textBeforeEnd: '\\t// }'}),\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 16, textBeforeStart: '\\t', target: '//=> [\\'a\\', \\'c\\']'}),\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 18, textBeforeStart: '\\t', target: '//=> Set'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\tNote:\n\t\t\t\t1. First point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst foo = {a: true, b: false, c: {d: true}} as const;\n\t\t\t\t\t//=> {\n\t\t\t\t\t// \treadonly a: true;\n\t\t\t\t\t// \treadonly b: false;\n\t\t\t\t\t// \treadonly c: {\n\t\t\t\t\t// \t\treadonly d: true;\n\t\t\t\t\t// \t};\n\t\t\t\t\t// }\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t2. Second point\n\t\t\t\t\t\\`\\`\\`ts\n\t\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t\t//=> readonly ['a', 'b', 'c']\n\t\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t\t//=> Set<'a' | 'b' | 'c'>\n\t\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Multiple `//=>`\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: true, b: false, c: {d: true}} as const;\n\t\t\t\t//=>\n\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t//=>\n\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t//=>\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', target: '//=>'}),\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 6, textBeforeStart: '', target: '//=>'}),\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 8, textBeforeStart: '', target: '//=>'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\tconst foo = {a: true, b: false, c: {d: true}} as const;\n\t\t\t\t//=> {\n\t\t\t\t// \treadonly a: true;\n\t\t\t\t// \treadonly b: false;\n\t\t\t\t// \treadonly c: {\n\t\t\t\t// \t\treadonly d: true;\n\t\t\t\t// \t};\n\t\t\t\t// }\n\t\t\t\tconst bar = ['a', 'b', 'c'] as const;\n\t\t\t\t//=> readonly ['a', 'b', 'c']\n\t\t\t\tconst baz = new Set(bar);\n\t\t\t\t//=> Set<'a' | 'b' | 'c'>\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Fixer suggests types at `Infinity` verbosity level\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = {foo: Pick<{bar: Pick<{baz: string}, 'baz'>}, 'bar'>};\n\t\t\t\t//=>\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', target: '//=>'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = {foo: Pick<{bar: Pick<{baz: string}, 'baz'>}, 'bar'>};\n\t\t\t\t//=> {foo: {bar: {baz: string}}}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\n\t\t// Only `0` and `Infinity` verbosity levels are allowed by default\n\t\t{\n\t\t\tcode: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = {foo: Pick<{bar: Pick<{baz: string}, 'baz'>}, 'bar'>};\n\t\t\t\t//=> {foo: {bar: Pick<{baz: string}, 'baz'>}}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t\terrors: [\n\t\t\t\tincorrectTwoslashTypeErrorAt({line: 4, textBeforeStart: '', target: '//=> {foo: {bar: Pick<{baz: string}, \\'baz\\'>}}'}),\n\t\t\t],\n\t\t\toutput: dedenter`\n\t\t\t\t/**\n\t\t\t\t\\`\\`\\`ts\n\t\t\t\ttype Test = {foo: Pick<{bar: Pick<{baz: string}, 'baz'>}, 'bar'>};\n\t\t\t\t//=> {foo: {bar: {baz: string}}}\n\t\t\t\t\\`\\`\\`\n\t\t\t\t*/\n\t\t\t\texport type T0 = string;\n\t\t\t`,\n\t\t},\n\t],\n});\n" }, { "path": "media/readme.md", "content": "# Media\n\n## Attribution\n\n### Fireworks vector graphic\n\n[Free Vectors via Vecteezy!](https://www.vecteezy.com)\n" }, { "path": "package.json", "content": "{\n\t\"name\": \"type-fest\",\n\t\"version\": \"5.5.0\",\n\t\"description\": \"A collection of essential TypeScript types\",\n\t\"license\": \"(MIT OR CC0-1.0)\",\n\t\"repository\": \"sindresorhus/type-fest\",\n\t\"funding\": \"https://github.com/sponsors/sindresorhus\",\n\t\"author\": {\n\t\t\"name\": \"Sindre Sorhus\",\n\t\t\"email\": \"sindresorhus@gmail.com\",\n\t\t\"url\": \"https://sindresorhus.com\"\n\t},\n\t\"type\": \"module\",\n\t\"exports\": {\n\t\t\".\": {\n\t\t\t\"types\": \"./index.d.ts\"\n\t\t},\n\t\t\"./globals\": {\n\t\t\t\"types\": \"./source/globals/index.d.ts\"\n\t\t}\n\t},\n\t\"types\": \"./index.d.ts\",\n\t\"sideEffects\": false,\n\t\"engines\": {\n\t\t\"node\": \">=20\"\n\t},\n\t\"scripts\": {\n\t\t\"test:tsc\": \"node --max-old-space-size=6144 ./node_modules/.bin/tsc\",\n\t\t\"test:tsd\": \"node --max-old-space-size=6144 ./node_modules/.bin/tsd\",\n\t\t\"test:xo\": \"node --max-old-space-size=6144 ./node_modules/.bin/xo --ignores=lint-processors/fixtures/**/*.d.ts\",\n\t\t\"test:linter\": \"node --test\",\n\t\t\"test\": \"run-p test:*\"\n\t},\n\t\"files\": [\n\t\t\"index.d.ts\",\n\t\t\"source\",\n\t\t\"license-mit\",\n\t\t\"license-cc0\"\n\t],\n\t\"keywords\": [\n\t\t\"typescript\",\n\t\t\"ts\",\n\t\t\"types\",\n\t\t\"utility\",\n\t\t\"util\",\n\t\t\"utilities\",\n\t\t\"omit\",\n\t\t\"merge\",\n\t\t\"json\",\n\t\t\"generics\"\n\t],\n\t\"dependencies\": {\n\t\t\"tagged-tag\": \"^1.0.0\"\n\t},\n\t\"devDependencies\": {\n\t\t\"@sindresorhus/tsconfig\": \"^8.0.1\",\n\t\t\"@typescript-eslint/parser\": \"^8.44.0\",\n\t\t\"eslint\": \"^9.35.0\",\n\t\t\"@typescript/vfs\": \"^1.6.1\",\n\t\t\"dedent\": \"^1.7.0\",\n\t\t\"expect-type\": \"^1.2.2\",\n\t\t\"npm-run-all2\": \"^8.0.4\",\n\t\t\"tsd\": \"^0.33.0\",\n\t\t\"typescript\": \"^5.9.2\",\n\t\t\"typescript-eslint\": \"^8.47.0\",\n\t\t\"xo\": \"^1.2.2\"\n\t},\n\t\"tsd\": {\n\t\t\"compilerOptions\": {\n\t\t\t\"noUnusedLocals\": false\n\t\t}\n\t}\n}\n" }, { "path": "readme.md", "content": "
\n\t
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\n\t\"type-fest\"\n\t
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\n\tA collection of essential TypeScript types\n\t
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\n\n[![](https://img.shields.io/badge/unicorn-approved-ff69b4.svg)](https://giphy.com/gifs/illustration-rainbow-unicorn-26AHG5KGFxSkUWw1i)\n[![npm dependents](https://badgen.net/npm/dependents/type-fest)](https://www.npmjs.com/package/type-fest?activeTab=dependents)\n[![npm downloads](https://badgen.net/npm/dt/type-fest)](https://www.npmjs.com/package/type-fest)\n\nMany of the types here should have been built-in. You can help by suggesting some of them to the [TypeScript project](https://github.com/Microsoft/TypeScript/blob/main/CONTRIBUTING.md).\n\nEither add this package as a dependency or copy-paste the needed types. No credit required. 👌\n\nPR welcome for additional commonly needed types and docs improvements. Read the [contributing guidelines](.github/contributing.md) first.\n\n**Help wanted with reviewing [proposals](https://github.com/sindresorhus/type-fest/issues) and [pull requests](https://github.com/sindresorhus/type-fest/pulls).**\n\n## Install\n\n```sh\nnpm install type-fest\n```\n\n*Requires TypeScript >=5.9, [ESM](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c), and [`{strict: true}`](https://www.typescriptlang.org/tsconfig#strict) in your tsconfig.*\n\n> [!NOTE]\n> This readme shows the current development version. For docs about the latest version, see the [npm page](https://www.npmjs.com/package/type-fest).\n\n*You may also like my [`ts-extras`](https://github.com/sindresorhus/ts-extras) package which provides runtime functions for some of these types.*\n\n## Usage\n\n```ts\nimport type {Except} from 'type-fest';\n\ntype Foo = {\n\tunicorn: string;\n\trainbow: boolean;\n};\n\ntype FooWithoutRainbow = Except;\n//=> {unicorn: string}\n```\n\n## API\n\nClick the type names for complete docs.\n\n### Basic\n\n- [`Primitive`](source/primitive.d.ts) - Matches any [primitive value](https://developer.mozilla.org/en-US/docs/Glossary/Primitive).\n- [`Class`](source/basic.d.ts) - Matches a [`class`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes).\n- [`Constructor`](source/basic.d.ts) - Matches a [`class` constructor](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes).\n- [`AbstractClass`](source/basic.d.ts) - Matches an [`abstract class`](https://www.typescriptlang.org/docs/handbook/2/classes.html#abstract-classes-and-members).\n- [`AbstractConstructor`](source/basic.d.ts) - Matches an [`abstract class`](https://www.typescriptlang.org/docs/handbook/release-notes/typescript-4-2.html#abstract-construct-signatures) constructor.\n- [`TypedArray`](source/typed-array.d.ts) - Matches any [typed array](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray), like `Uint8Array` or `Float64Array`.\n- [`ObservableLike`](source/globals/observable-like.d.ts) - Matches a value that is like an [Observable](https://github.com/tc39/proposal-observable).\n- [`LowercaseLetter`](source/characters.d.ts) - Matches any lowercase letter in the basic Latin alphabet (a-z).\n- [`UppercaseLetter`](source/characters.d.ts) - Matches any uppercase letter in the basic Latin alphabet (A-Z).\n- [`DigitCharacter`](source/characters.d.ts) - Matches any digit as a string ('0'-'9').\n- [`Alphanumeric`](source/characters.d.ts) - Matches any lowercase letter (a-z), uppercase letter (A-Z), or digit ('0'-'9') in the basic Latin alphabet.\n\n### Utilities\n\n- [`EmptyObject`](source/empty-object.d.ts) - Represents a strictly empty plain object, the `{}` value.\n- [`NonEmptyObject`](source/non-empty-object.d.ts) - Represents an object with at least 1 non-optional key.\n- [`UnknownRecord`](source/unknown-record.d.ts) - Represents an object with `unknown` value. You probably want this instead of `{}`.\n- [`UnknownArray`](source/unknown-array.d.ts) - Represents an array with `unknown` value.\n- [`UnknownMap`](source/unknown-map.d.ts) - Represents a map with `unknown` key and value.\n- [`UnknownSet`](source/unknown-set.d.ts) - Represents a set with `unknown` value.\n- [`Except`](source/except.d.ts) - Create a type from an object type without certain keys. This is a stricter version of [`Omit`](https://www.typescriptlang.org/docs/handbook/utility-types.html#omittype-keys).\n- [`Writable`](source/writable.d.ts) - Create a type that strips `readonly` from the given type. Inverse of `Readonly`.\n- [`WritableDeep`](source/writable-deep.d.ts) - Create a deeply mutable version of an `object`/`ReadonlyMap`/`ReadonlySet`/`ReadonlyArray` type. The inverse of `ReadonlyDeep`. Use `Writable` if you only need one level deep.\n- [`Merge`](source/merge.d.ts) - Merge two types into a new type. Keys of the second type overrides keys of the first type.\n- [`ObjectMerge`](source/object-merge.d.ts) - Merge two object types into a new object type, where keys from the second override keys from the first.\n- [`MergeDeep`](source/merge-deep.d.ts) - Merge two objects or two arrays/tuples recursively into a new type.\n- [`MergeExclusive`](source/merge-exclusive.d.ts) - Create a type that has mutually exclusive keys.\n- [`OverrideProperties`](source/override-properties.d.ts) - Override only existing properties of the given type. Similar to `Merge`, but enforces that the original type has the properties you want to override.\n- [`RequireAtLeastOne`](source/require-at-least-one.d.ts) - Create a type that requires at least one of the given keys.\n- [`RequireExactlyOne`](source/require-exactly-one.d.ts) - Create a type that requires exactly a single key of the given keys and disallows more.\n- [`RequireAllOrNone`](source/require-all-or-none.d.ts) - Create a type that requires all of the given keys or none of the given keys.\n- [`RequireOneOrNone`](source/require-one-or-none.d.ts) - Create a type that requires exactly a single key of the given keys and disallows more, or none of the given keys.\n- [`SingleKeyObject`](source/single-key-object.d.ts) - Create a type that only accepts an object with a single key.\n- [`RequiredDeep`](source/required-deep.d.ts) - Create a deeply required version of another type. Use [`Required`](https://www.typescriptlang.org/docs/handbook/utility-types.html#requiredtype) if you only need one level deep.\n- [`PickDeep`](source/pick-deep.d.ts) - Pick properties from a deeply-nested object. Use [`Pick`](https://www.typescriptlang.org/docs/handbook/utility-types.html#picktype-keys) if you only need one level deep.\n- [`OmitDeep`](source/omit-deep.d.ts) - Omit properties from a deeply-nested object. Use [`Omit`](https://www.typescriptlang.org/docs/handbook/utility-types.html#omittype-keys) if you only need one level deep.\n- [`OmitIndexSignature`](source/omit-index-signature.d.ts) - Omit any index signatures from the given object type, leaving only explicitly defined properties.\n- [`PickIndexSignature`](source/pick-index-signature.d.ts) - Pick only index signatures from the given object type, leaving out all explicitly defined properties.\n- [`PartialDeep`](source/partial-deep.d.ts) - Create a deeply optional version of another type. Use [`Partial`](https://www.typescriptlang.org/docs/handbook/utility-types.html#partialtype) if you only need one level deep.\n- [`PartialOnUndefinedDeep`](source/partial-on-undefined-deep.d.ts) - Create a deep version of another type where all keys accepting `undefined` type are set to optional.\n- [`UndefinedOnPartialDeep`](source/undefined-on-partial-deep.d.ts) - Create a deep version of another type where all optional keys are set to also accept `undefined`.\n- [`UnwrapPartial`](source/unwrap-partial.d.ts) - Revert the `Partial` modifier on an object type.\n- [`ReadonlyDeep`](source/readonly-deep.d.ts) - Create a deeply immutable version of an `object`/`Map`/`Set`/`Array` type. Use [`Readonly`](https://www.typescriptlang.org/docs/handbook/utility-types.html#readonlytype) if you only need one level deep.\n- [`LiteralUnion`](source/literal-union.d.ts) - Create a union type by combining primitive types and literal types without sacrificing auto-completion in IDEs for the literal type part of the union. Workaround for [Microsoft/TypeScript#29729](https://github.com/Microsoft/TypeScript/issues/29729).\n- [`Tagged`](source/tagged.d.ts) - Create a [tagged type](https://medium.com/@KevinBGreene/surviving-the-typescript-ecosystem-branding-and-type-tagging-6cf6e516523d) that can support [multiple tags](https://github.com/sindresorhus/type-fest/issues/665) and [per-tag metadata](https://medium.com/@ethanresnick/advanced-typescript-tagged-types-improved-with-type-level-metadata-5072fc125fcf). (This replaces the previous [`Opaque`](source/tagged.d.ts) type, which is now deprecated.)\n- [`UnwrapTagged`](source/tagged.d.ts) - Get the untagged portion of a tagged type created with `Tagged`. (This replaces the previous [`UnwrapOpaque`](source/tagged.d.ts) type, which is now deprecated.)\n- [`InvariantOf`](source/invariant-of.d.ts) - Create an [invariant type](https://basarat.gitbook.io/typescript/type-system/type-compatibility#footnote-invariance), which is a type that does not accept supertypes and subtypes.\n- [`SetOptional`](source/set-optional.d.ts) - Create a type that makes the given keys optional.\n- [`SetReadonly`](source/set-readonly.d.ts) - Create a type that makes the given keys readonly.\n- [`SetRequired`](source/set-required.d.ts) - Create a type that makes the given keys required.\n- [`SetRequiredDeep`](source/set-required-deep.d.ts) - Like `SetRequired` except it selects the keys deeply.\n- [`SetNonNullable`](source/set-non-nullable.d.ts) - Create a type that makes the given keys non-nullable.\n- [`SetNonNullableDeep`](source/set-non-nullable-deep.d.ts) - Create a type that makes the specified keys non-nullable (removes `null` and `undefined`), supports deeply nested key paths, and leaves all other keys unchanged.\n- [`ValueOf`](source/value-of.d.ts) - Create a union of the given object's values, and optionally specify which keys to get the values from.\n- [`ConditionalKeys`](source/conditional-keys.d.ts) - Extract keys from a shape where values extend the given `Condition` type.\n- [`ConditionalPick`](source/conditional-pick.d.ts) - Like `Pick` except it selects properties from a shape where the values extend the given `Condition` type.\n- [`ConditionalPickDeep`](source/conditional-pick-deep.d.ts) - Like `ConditionalPick` except that it selects the properties deeply.\n- [`ConditionalExcept`](source/conditional-except.d.ts) - Like `Omit` except it removes properties from a shape where the values extend the given `Condition` type.\n- [`UnionToIntersection`](source/union-to-intersection.d.ts) - Convert a union type to an intersection type.\n- [`LiteralToPrimitive`](source/literal-to-primitive.d.ts) - Convert a [literal type](https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#literal-types) to the [primitive type](source/primitive.d.ts) it belongs to.\n- [`LiteralToPrimitiveDeep`](source/literal-to-primitive-deep.d.ts) - Like `LiteralToPrimitive` except it converts literal types inside an object or array deeply.\n- [`Stringified`](source/stringified.d.ts) - Create a type with the keys of the given type changed to `string` type.\n- [`IterableElement`](source/iterable-element.d.ts) - Get the element type of an `Iterable`/`AsyncIterable`. For example, `Array`, `Set`, `Map`, generator, stream, etc.\n- [`Entry`](source/entry.d.ts) - Create a type that represents the type of an entry of a collection.\n- [`Entries`](source/entries.d.ts) - Create a type that represents the type of the entries of a collection.\n- [`SetReturnType`](source/set-return-type.d.ts) - Create a function type with a return type of your choice and the same parameters as the given function type.\n- [`SetParameterType`](source/set-parameter-type.d.ts) - Create a function that replaces some parameters with the given parameters.\n- [`Simplify`](source/simplify.d.ts) - Useful to flatten the type output to improve type hints shown in editors. And also to transform an interface into a type to aide with assignability.\n- [`SimplifyDeep`](source/simplify-deep.d.ts) - Deeply simplifies an object type.\n- [`Get`](source/get.d.ts) - Get a deeply-nested property from an object using a key path, like [Lodash's `.get()`](https://lodash.com/docs/latest#get) function.\n- [`KeyAsString`](source/key-as-string.d.ts) - Get keys of the given type as strings.\n- [`Schema`](source/schema.d.ts) - Create a deep version of another object type where property values are recursively replaced into a given value type.\n- [`Exact`](source/exact.d.ts) - Create a type that does not allow extra properties.\n- [`KeysOfUnion`](source/keys-of-union.d.ts) - Create a union of all keys from a given type, even those exclusive to specific union members.\n- [`OptionalKeysOf`](source/optional-keys-of.d.ts) - Extract all optional keys from the given type.\n- [`HasOptionalKeys`](source/has-optional-keys.d.ts) - Create a `true`/`false` type depending on whether the given type has any optional fields.\n- [`RequiredKeysOf`](source/required-keys-of.d.ts) - Extract all required keys from the given type.\n- [`HasRequiredKeys`](source/has-required-keys.d.ts) - Create a `true`/`false` type depending on whether the given type has any required fields.\n- [`ReadonlyKeysOf`](source/readonly-keys-of.d.ts) - Extract all readonly keys from the given type.\n- [`HasReadonlyKeys`](source/has-readonly-keys.d.ts) - Create a `true`/`false` type depending on whether the given type has any readonly fields.\n- [`WritableKeysOf`](source/writable-keys-of.d.ts) - Extract all writable (non-readonly) keys from the given type.\n- [`HasWritableKeys`](source/has-writable-keys.d.ts) - Create a `true`/`false` type depending on whether the given type has any writable fields.\n- [`Spread`](source/spread.d.ts) - Mimic the type inferred by TypeScript when merging two objects or two arrays/tuples using the spread syntax.\n- [`IsEqual`](source/is-equal.d.ts) - Returns a boolean for whether the two given types are equal.\n- [`TaggedUnion`](source/tagged-union.d.ts) - Create a union of types that share a common discriminant property.\n- [`IntRange`](source/int-range.d.ts) - Generate a union of numbers (includes the start and excludes the end).\n- [`IntClosedRange`](source/int-closed-range.d.ts) - Generate a union of numbers (includes the start and the end).\n- [`ArrayIndices`](source/array-indices.d.ts) - Provides valid indices for a constant array or tuple.\n- [`ArrayValues`](source/array-values.d.ts) - Provides all values for a constant array or tuple.\n- [`ArraySplice`](source/array-splice.d.ts) - Create a new array type by adding or removing elements at a specified index range in the original array.\n- [`ArrayTail`](source/array-tail.d.ts) - Extract the type of an array or tuple minus the first element.\n- [`SetFieldType`](source/set-field-type.d.ts) - Create a type that changes the type of the given keys.\n- [`Paths`](source/paths.d.ts) - Generate a union of all possible paths to properties in the given object.\n- [`SharedUnionFields`](source/shared-union-fields.d.ts) - Create a type with shared fields from a union of object types.\n- [`SharedUnionFieldsDeep`](source/shared-union-fields-deep.d.ts) - Create a type with shared fields from a union of object types, deeply traversing nested structures.\n- [`AllUnionFields`](source/all-union-fields.d.ts) - Create a type with all fields from a union of object types.\n- [`DistributedOmit`](source/distributed-omit.d.ts) - Omits keys from a type, distributing the operation over a union.\n- [`DistributedPick`](source/distributed-pick.d.ts) - Picks keys from a type, distributing the operation over a union.\n- [`And`](source/and.d.ts) - Returns a boolean for whether two given types are both `true`.\n- [`Or`](source/or.d.ts) - Returns a boolean for whether either of two given types is `true`.\n- [`Xor`](source/xor.d.ts) - Returns a boolean for whether only one of two given types is `true`.\n- [`AndAll`](source/and-all.d.ts) - Returns a boolean for whether all of the given elements are `true`.\n- [`OrAll`](source/or-all.d.ts) - Returns a boolean for whether any of the given elements is `true`.\n- [`AllExtend`](source/all-extend.d.ts) - Returns a boolean for whether every element in an array type extends another type.\n- [`SomeExtend`](source/some-extend.d.ts) - Returns a boolean for whether some element in an array type extends another type.\n- [`NonEmptyTuple`](source/non-empty-tuple.d.ts) - Matches any non-empty tuple.\n- [`NonEmptyString`](source/non-empty-string.d.ts) - Matches any non-empty string.\n- [`FindGlobalType`](source/find-global-type.d.ts) - Tries to find the type of a global with the given name.\n- [`FindGlobalInstanceType`](source/find-global-type.d.ts) - Tries to find one or more types from their globally-defined constructors.\n- [`ConditionalSimplify`](source/conditional-simplify.d.ts) - Simplifies a type while including and/or excluding certain types from being simplified.\n- [`ConditionalSimplifyDeep`](source/conditional-simplify-deep.d.ts) - Recursively simplifies a type while including and/or excluding certain types from being simplified.\n- [`ExclusifyUnion`](source/exclusify-union.d.ts) - Ensure mutual exclusivity in object unions by adding other members’ keys as `?: never`.\n- [`Optional`](source/optional.d.ts) - Create a type that represents either the value or `undefined`, while stripping `null` from the type.\n- [`UnionMember`](source/union-member.d.ts) - Returns an arbitrary member of a union type.\n\n### Type Guard\n\n- [`If`](source/if.d.ts) - An if-else-like type that resolves depending on whether the given `boolean` type is `true` or `false`.\n- [`IsLiteral`](source/is-literal.d.ts) - Returns a boolean for whether the given type is a [literal type](https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#literal-types).\n- [`IsStringLiteral`](source/is-literal.d.ts) - Returns a boolean for whether the given type is a `string` [literal type](https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#literal-types).\n- [`IsNumericLiteral`](source/is-literal.d.ts) - Returns a boolean for whether the given type is a `number` or `bigint` [literal type](https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#literal-types).\n- [`IsBooleanLiteral`](source/is-literal.d.ts) - Returns a boolean for whether the given type is a `true` or `false` [literal type](https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#literal-types).\n- [`IsSymbolLiteral`](source/is-literal.d.ts) - Returns a boolean for whether the given type is a `symbol` [literal type](https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#literal-types).\n- [`IsAny`](source/is-any.d.ts) - Returns a boolean for whether the given type is `any`.\n- [`IsNever`](source/is-never.d.ts) - Returns a boolean for whether the given type is `never`.\n- [`IsUnknown`](source/is-unknown.d.ts) - Returns a boolean for whether the given type is `unknown`.\n- [`IsEmptyObject`](source/empty-object.d.ts) - Returns a boolean for whether the type is strictly equal to an empty plain object, the `{}` value.\n- [`IsNull`](source/is-null.d.ts) - Returns a boolean for whether the given type is `null`.\n- [`IsUndefined`](source/is-undefined.d.ts) - Returns a boolean for whether the given type is `undefined`.\n- [`IsTuple`](source/is-tuple.d.ts) - Returns a boolean for whether the given array is a tuple.\n- [`IsUnion`](source/is-union.d.ts) - Returns a boolean for whether the given type is a union.\n- [`IsLowercase`](source/is-lowercase.d.ts) - Returns a boolean for whether the given string literal is lowercase.\n- [`IsUppercase`](source/is-uppercase.d.ts) - Returns a boolean for whether the given string literal is uppercase.\n- [`IsOptional`](source/is-optional.d.ts) - Returns a boolean for whether the given type includes `undefined`.\n- [`IsNullable`](source/is-nullable.d.ts) - Returns a boolean for whether the given type includes `null`.\n- [`IsOptionalKeyOf`](source/is-optional-key-of.d.ts) - Returns a boolean for whether the given key is an optional key of type.\n- [`IsRequiredKeyOf`](source/is-required-key-of.d.ts) - Returns a boolean for whether the given key is a required key of type.\n- [`IsReadonlyKeyOf`](source/is-readonly-key-of.d.ts) - Returns a boolean for whether the given key is a readonly key of type.\n- [`IsWritableKeyOf`](source/is-writable-key-of.d.ts) - Returns a boolean for whether the given key is a writable key of type.\n\n### JSON\n\n- [`Jsonify`](source/jsonify.d.ts) - Transform a type to one that is assignable to the `JsonValue` type.\n- [`Jsonifiable`](source/jsonifiable.d.ts) - Matches a value that can be losslessly converted to JSON.\n- [`JsonPrimitive`](source/json-value.d.ts) - Matches a JSON primitive.\n- [`JsonObject`](source/json-value.d.ts) - Matches a JSON object.\n- [`JsonArray`](source/json-value.d.ts) - Matches a JSON array.\n- [`JsonValue`](source/json-value.d.ts) - Matches any valid JSON value.\n\n### Structured clone\n\n- [`StructuredCloneable`](source/structured-cloneable.d.ts) - Matches a value that can be losslessly cloned using `structuredClone`.\n\n### Async\n\n- [`Promisable`](source/promisable.d.ts) - Create a type that represents either the value or the value wrapped in `PromiseLike`.\n- [`AsyncReturnType`](source/async-return-type.d.ts) - Unwrap the return type of a function that returns a `Promise`.\n- [`Asyncify`](source/asyncify.d.ts) - Create an async version of the given function type.\n\n### String\n\n- [`Trim`](source/trim.d.ts) - Remove leading and trailing spaces from a string.\n- [`Split`](source/split.d.ts) - Represents an array of strings split using a given character or character set.\n- [`Words`](source/words.d.ts) - Represents an array of strings split using a heuristic for detecting words.\n- [`Replace`](source/replace.d.ts) - Represents a string with some or all matches replaced by a replacement.\n- [`StringSlice`](source/string-slice.d.ts) - Returns a string slice of a given range, just like `String#slice()`.\n- [`StringRepeat`](source/string-repeat.d.ts) - Returns a new string which contains the specified number of copies of a given string, just like `String#repeat()`.\n- [`RemovePrefix`](source/remove-prefix.d.ts) - Remove the specified prefix from the start of a string.\n\n### Array\n\n- [`Arrayable`](source/arrayable.d.ts) - Create a type that represents either the value or an array of the value.\n- [`Includes`](source/includes.d.ts) - Returns a boolean for whether the given array includes the given item.\n- [`Join`](source/join.d.ts) - Join an array of strings and/or numbers using the given string as a delimiter.\n- [`ArraySlice`](source/array-slice.d.ts) - Returns an array slice of a given range, just like `Array#slice()`.\n- [`ArrayElement`](source/array-element.d.ts) - Extracts the element type of an array or tuple.\n- [`LastArrayElement`](source/last-array-element.d.ts) - Extract the type of the last element of an array.\n- [`FixedLengthArray`](source/fixed-length-array.d.ts) - Create a type that represents an array of the given type and length. The `Array` prototype methods that manipulate its length are excluded from the resulting type.\n- [`MultidimensionalArray`](source/multidimensional-array.d.ts) - Create a type that represents a multidimensional array of the given type and dimensions.\n- [`MultidimensionalReadonlyArray`](source/multidimensional-readonly-array.d.ts) - Create a type that represents a multidimensional readonly array of the given type and dimensions.\n- [`ReadonlyTuple`](source/readonly-tuple.d.ts) - Create a type that represents a read-only tuple of the given type and length.\n- [`TupleToUnion`](source/tuple-to-union.d.ts) - Convert a tuple/array into a union type of its elements.\n- [`UnionToTuple`](source/union-to-tuple.d.ts) - Convert a union type into an unordered tuple type of its elements.\n- [`TupleToObject`](source/tuple-to-object.d.ts) - Transforms a tuple into an object, mapping each tuple index to its corresponding type as a key-value pair.\n- [`TupleOf`](source/tuple-of.d.ts) - Create a tuple type of the specified length with elements of the specified type.\n- [`SplitOnRestElement`](source/split-on-rest-element.d.ts) - Splits an array into three parts, where the first contains all elements before the rest element, the second is the [`rest`](https://www.typescriptlang.org/docs/handbook/2/objects.html#tuple-types) element itself, and the third contains all elements after the rest element.\n- [`ExtractRestElement`](source/extract-rest-element.d.ts) - Extract the [`rest`](https://www.typescriptlang.org/docs/handbook/2/objects.html#tuple-types) element type from an array.\n- [`ExcludeRestElement`](source/exclude-rest-element.d.ts) - Create a tuple with the [`rest`](https://www.typescriptlang.org/docs/handbook/2/objects.html#tuple-types) element removed.\n- [`ArrayReverse`](source/array-reverse.d.ts) - Reverse the order of elements in a tuple type.\n- [`ArrayLength`](source/array-length.d.ts) - Return the length of an array. Equivalent to `T['length']` where `T` extends any array.\n\n### Numeric\n\n- [`PositiveInfinity`](source/numeric.d.ts) - Matches the hidden `Infinity` type.\n- [`NegativeInfinity`](source/numeric.d.ts) - Matches the hidden `-Infinity` type.\n- [`Finite`](source/numeric.d.ts) - A finite `number`.\n- [`Integer`](source/numeric.d.ts) - A `number` that is an integer.\n- [`Float`](source/numeric.d.ts) - A `number` that is not an integer.\n- [`NegativeFloat`](source/numeric.d.ts) - A negative (`-∞ < x < 0`) `number` that is not an integer.\n- [`Negative`](source/numeric.d.ts) - A negative `number`/`bigint` (`-∞ < x < 0`)\n- [`NonNegative`](source/numeric.d.ts) - A non-negative `number`/`bigint` (`0 <= x < ∞`).\n- [`NegativeInteger`](source/numeric.d.ts) - A negative (`-∞ < x < 0`) `number` that is an integer.\n- [`NonNegativeInteger`](source/numeric.d.ts) - A non-negative (`0 <= x < ∞`) `number` that is an integer.\n- [`IsNegative`](source/numeric.d.ts) - Returns a boolean for whether the given number is a negative number.\n- [`IsFloat`](source/is-float.d.ts) - Returns a boolean for whether the given number is a float, like `1.5` or `-1.5`.\n- [`IsInteger`](source/is-integer.d.ts) - Returns a boolean for whether the given number is an integer, like `-5`, `1.0` or `100`.\n- [`GreaterThan`](source/greater-than.d.ts) - Returns a boolean for whether a given number is greater than another number.\n- [`GreaterThanOrEqual`](source/greater-than-or-equal.d.ts) - Returns a boolean for whether a given number is greater than or equal to another number.\n- [`LessThan`](source/less-than.d.ts) - Returns a boolean for whether a given number is less than another number.\n- [`LessThanOrEqual`](source/less-than-or-equal.d.ts) - Returns a boolean for whether a given number is less than or equal to another number.\n- [`Sum`](source/sum.d.ts) - Returns the sum of two numbers.\n- [`Subtract`](source/subtract.d.ts) - Returns the difference between two numbers.\n\n### Change case\n\n- [`CamelCase`](source/camel-case.d.ts) - Convert a string literal to camel-case (`fooBar`).\n- [`CamelCasedProperties`](source/camel-cased-properties.d.ts) - Convert object properties to camel-case (`fooBar`).\n- [`CamelCasedPropertiesDeep`](source/camel-cased-properties-deep.d.ts) - Convert object properties to camel-case recursively (`fooBar`).\n- [`KebabCase`](source/kebab-case.d.ts) - Convert a string literal to kebab-case (`foo-bar`).\n- [`KebabCasedProperties`](source/kebab-cased-properties.d.ts) - Convert object properties to kebab-case (`foo-bar`).\n- [`KebabCasedPropertiesDeep`](source/kebab-cased-properties-deep.d.ts) - Convert object properties to kebab-case recursively (`foo-bar`).\n- [`PascalCase`](source/pascal-case.d.ts) - Convert a string literal to pascal-case (`FooBar`).\n- [`PascalCasedProperties`](source/pascal-cased-properties.d.ts) - Convert object properties to pascal-case (`FooBar`).\n- [`PascalCasedPropertiesDeep`](source/pascal-cased-properties-deep.d.ts) - Convert object properties to pascal-case recursively (`FooBar`).\n- [`SnakeCase`](source/snake-case.d.ts) - Convert a string literal to snake-case (`foo_bar`).\n- [`SnakeCasedProperties`](source/snake-cased-properties.d.ts) - Convert object properties to snake-case (`foo_bar`).\n- [`SnakeCasedPropertiesDeep`](source/snake-cased-properties-deep.d.ts) - Convert object properties to snake-case recursively (`foo_bar`).\n- [`ScreamingSnakeCase`](source/screaming-snake-case.d.ts) - Convert a string literal to screaming-snake-case (`FOO_BAR`).\n- [`DelimiterCase`](source/delimiter-case.d.ts) - Convert a string literal to a custom string delimiter casing.\n- [`DelimiterCasedProperties`](source/delimiter-cased-properties.d.ts) - Convert object properties to a custom string delimiter casing.\n- [`DelimiterCasedPropertiesDeep`](source/delimiter-cased-properties-deep.d.ts) - Convert object properties to a custom string delimiter casing recursively.\n\n### Miscellaneous\n\n- [`GlobalThis`](source/global-this.d.ts) - Declare locally scoped properties on `globalThis`.\n- [`PackageJson`](source/package-json.d.ts) - Type for [npm's `package.json` file](https://docs.npmjs.com/creating-a-package-json-file). It also includes support for [TypeScript Declaration Files](https://www.typescriptlang.org/docs/handbook/declaration-files/publishing.html).\n- [`TsConfigJson`](source/tsconfig-json.d.ts) - Type for [TypeScript's `tsconfig.json` file](https://www.typescriptlang.org/docs/handbook/tsconfig-json.html).\n\n### Improved built-in\n\n- [`ExtendsStrict`](source/extends-strict.d.ts) - A stricter, non-distributive version of `extends` for checking whether one type is assignable to another.\n- [`ExtractStrict`](source/extract-strict.d.ts) - A stricter version of `Extract` that ensures every member of `U` can successfully extract something from `T`.\n- [`ExcludeStrict`](source/exclude-strict.d.ts) - A stricter version of `Exclude` that ensures every member of `U` can successfully exclude something from `T`.\n- [`ExcludeExactly`](source/exclude-exactly.d.ts) - A stricter version of `Exclude` that excludes types only when they are exactly identical.\n\n## Declined types\n\n*If we decline a type addition, we will make sure to document the better solution here.*\n\n- [`Diff` and `Spread`](https://github.com/sindresorhus/type-fest/pull/7) - The pull request author didn't provide any real-world use-cases and the PR went stale. If you think this type is useful, provide some real-world use-cases and we might reconsider.\n- [`Dictionary`](https://github.com/sindresorhus/type-fest/issues/33) - You only save a few characters (`Dictionary` vs `Record`) from [`Record`](https://www.typescriptlang.org/docs/handbook/utility-types.html#recordkeys-type), which is more flexible and well-known. Also, you shouldn't use an object as a dictionary. We have `Map` in JavaScript now.\n- [`ExtractProperties` and `ExtractMethods`](https://github.com/sindresorhus/type-fest/pull/4) - The types violate the single responsibility principle. Instead, refine your types into more granular type hierarchies.\n- [`Url2Json`](https://github.com/sindresorhus/type-fest/pull/262) - Inferring search parameters from a URL string is a cute idea, but not very useful in practice, since search parameters are usually dynamic and defined separately.\n- [`Nullish`](https://github.com/sindresorhus/type-fest/pull/318) - The type only saves a couple of characters, not everyone knows what \"nullish\" means, and I'm also trying to [get away from `null`](https://github.com/sindresorhus/meta/discussions/7).\n- [`TitleCase`](https://github.com/sindresorhus/type-fest/pull/303) - It's not solving a common need and is a better fit for a separate package.\n- [`ExtendOr` and `ExtendAnd`](https://github.com/sindresorhus/type-fest/pull/247) - The benefits don't outweigh having to learn what they mean.\n- [`PackageJsonExtras`](https://github.com/sindresorhus/type-fest/issues/371) - There are too many possible configurations that can be put into `package.json`. If you would like to extend `PackageJson` to support an additional configuration in your project, please see the *Extending existing types* section below.\n\n## Alternative type names\n\n*If you know one of our types by a different name, add it here for discovery.*\n\n- `Prettify`- See [`Simplify`](source/simplify.d.ts)\n- `Expand`- See [`Simplify`](source/simplify.d.ts)\n- `PartialBy` - See [`SetOptional`](source/set-optional.d.ts)\n- `RecordDeep`- See [`Schema`](source/schema.d.ts)\n- `Mutable`- See [`Writable`](source/writable.d.ts)\n- `RequireOnlyOne`, `OneOf` - See [`RequireExactlyOne`](source/require-exactly-one.d.ts)\n- `AtMostOne` - See [`RequireOneOrNone`](source/require-one-or-none.d.ts)\n- `AllKeys` - See [`KeysOfUnion`](source/keys-of-union.d.ts)\n- `Branded` - See [`Tagged`](source/tagged.d.ts)\n- `Opaque` - See [`Tagged`](source/tagged.d.ts)\n- `SetElement` - See [`IterableElement`](source/iterable-element.d.ts)\n- `SetEntry` - See [`IterableElement`](source/iterable-element.d.ts)\n- `SetValues` - See [`IterableElement`](source/iterable-element.d.ts)\n- `PickByTypes` - See [`ConditionalPick`](source/conditional-pick.d.ts)\n- `HomomorphicOmit` - See [`Except`](source/except.d.ts)\n- `IfAny`, `IfNever`, `If*` - See [`If`](source/if.d.ts)\n- `Maybe`, `Option` - See [`Optional`](source/optional.d.ts)\n- `MaybePromise` - See [`Promisable`](source/promisable.d.ts)\n- `ReadonlyTuple` - See [`TupleOf`](source/tuple-of.d.ts)\n- `LastOfUnion` - See [`UnionMember`](source/union-member.d.ts)\n- `FirstOfUnion` - See [`UnionMember`](source/union-member.d.ts)\n\n## Tips\n\n### Extending existing types\n\n- [`PackageJson`](source/package-json.d.ts) - There are a lot of tools that place extra configurations inside the `package.json` file. You can extend `PackageJson` to support these additional configurations.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://www.typescriptlang.org/play?#code/JYWwDg9gTgLgBDAnmApnA3gBQIYGMDW2A5igFIDOEAdnNuXAEJ0o4HFmVUC+cAZlBBBwA5ElQBaXinIxhAbgCwAKFCRYCZGnQAZYFRgooPfoJHSANntmKlysWlaESFanAC8jZo-YuaAMgwLKwBhal5gIgB+AC44XX1DADpQqnCiLhsgA)\n\n\t```ts\n\timport type {PackageJson as BasePackageJson} from 'type-fest';\n\timport type {Linter} from 'eslint';\n\n\ttype PackageJson = BasePackageJson & {eslintConfig?: Linter.Config};\n\t```\n\t
\n\n### Related\n\n- [typed-query-selector](https://github.com/g-plane/typed-query-selector) - Enhances `document.querySelector` and `document.querySelectorAll` with a template literal type that matches element types returned from an HTML element query selector.\n- [`Linter.Config`](https://github.com/eslint/eslint/blob/main/lib/types/index.d.ts) - Definitions for the [ESLint configuration schema](https://eslint.org/docs/user-guide/configuring/language-options).\n\n### Built-in types\n\nThere are many advanced types most users don't know about.\n\n\n- [`Awaited`](https://www.typescriptlang.org/docs/handbook/utility-types.html#awaitedtype) - Extract the type of a value that a `Promise` resolves to.\n
\n \n \tExample\n \n\n [Playground](https://www.typescriptlang.org/play/?#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-C1QcxIKhJc0mWNWhngwK0YJQEJpdj8Wy5mEIU4rQFURXuZWq+5PF4raPJuPte0eHQ+fxkXHpWG6GCQKBOApuITIQGNCMM2xRGgqIPIeWwKJQOqmOACadafr+rToGiFDSj-RNEfFUo6EbgaDwJB0vGz9wnhqImpRb2Es8QBlLhZwDYjuBkGQrz+kMyC6OEfjnBAACONCXGAm5aCAEDKsqHTpPIs4fMgXjQNE2aFhkxx4d+gbBqoQjWJKChKKIxbwqWZqGI2VpqtQECPNo0BJpaSA4tCZEhhAYYRu23HMbxn7IDSUJAA)\n\n ```ts\n interface User {\n \tid: number;\n \tname: string;\n \tage: number;\n }\n\n class UserApiService {\n \tasync fetchUser(userId: number): Promise {\n \t\t// Fetch the user data from the database.\n \t\t// The actual implementation might look like this:\n \t\t// const response = await fetch('/api/user/${userId}');\n \t\t// const data = response.json();\n \t\t// return data;\n \t\treturn {\n \t\t\tid: 1,\n \t\t\tname: 'John Doe',\n \t\t\tage: 30\n \t\t};\n \t}\n }\n\n type FetchedUser = Awaited>;\n\n async function handleUserData(apiService: UserApiService, userId: number) {\n \ttry {\n \t\tconst user: FetchedUser = await apiService.fetchUser(userId);\n \t\t// After fetching user data, you can perform various actions such as updating the user interface,\n \t\t// caching the data for future use, or making additional API requests as needed.\n \t} catch (error) {\n \t\t// Error handling\n \t}\n }\n\n const userApiService = new UserApiService();\n handleUserData(userApiService, 1);\n ```\n\n- [`Partial`](https://www.typescriptlang.org/docs/handbook/utility-types.html#partialtype) - Make all properties in `T` optional.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://www.typescriptlang.org/play/#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)\n\n\t```ts\n\tinterface NodeConfig {\n\t\t\tappName: string;\n\t\t\tport: number;\n\t}\n\n\tclass NodeAppBuilder {\n\t\t\tprivate configuration: NodeConfig = {\n\t\t\t\t\tappName: 'NodeApp',\n\t\t\t\t\tport: 3000\n\t\t\t};\n\n\t\t\tprivate updateConfig(key: Key, value: NodeConfig[Key]) {\n\t\t\t\t\tthis.configuration[key] = value;\n\t\t\t}\n\n\t\t\tconfig(config: Partial) {\n\t\t\t\t\ttype NodeConfigKey = keyof NodeConfig;\n\n\t\t\t\t\tfor (const key of Object.keys(config) as NodeConfigKey[]) {\n\t\t\t\t\t\t\tconst updateValue = config[key];\n\n\t\t\t\t\t\t\tif (updateValue === undefined) {\n\t\t\t\t\t\t\t\t\tcontinue;\n\t\t\t\t\t\t\t}\n\n\t\t\t\t\t\t\tthis.updateConfig(key, updateValue);\n\t\t\t\t\t}\n\n\t\t\t\t\treturn this;\n\t\t\t}\n\t}\n\n\t// `Partial`` allows us to provide only a part of the\n\t// NodeConfig interface.\n\tnew NodeAppBuilder().config({appName: 'ToDoApp'});\n\t```\n\n\t`Partial` can be reverted with [`UnwrapPartial`](source/unwrap-partial.d.ts).\n\t
\n\n- [`Required`](https://www.typescriptlang.org/docs/handbook/utility-types.html#requiredtype) - Make all properties in `T` required.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#code/AQ4SwOwFwUwJwGYEMDGNgGED21VQGJZwC2wA3gFCjXAzFJgA2A-AFzADOUckA5gNxUaIYjA4ckvGG07c+g6gF8KQkAgCuEFFDA5O6gEbEwUbLm2ESwABQIixACJIoSdgCUYAR3Vg4MACYAPGYuFvYAfACU5Ko0APRxwADKMBD+wFAAFuh2Vv7OSBlYGdmc8ABu8LHKsRyGxqY4oQT21pTCIHQMjOwA5DAAHgACxAAOjDAAdChYxL0ANLHUouKSMH0AEmAAhJhY6ozpAJ77GTCMjMCiV0ToSAb7UJPPC9WRgrEJwAAqR6MwSRQPFGUFocDgRHYxnEfGAowh-zgUCOwF6KwkUl6tXqJhCeEsxDaS1AXSYfUGI3GUxmc0WSneQA)\n\n\t```ts\n\tinterface ContactForm {\n\t\t\temail?: string;\n\t\t\tmessage?: string;\n\t}\n\n\tfunction submitContactForm(formData: Required) {\n\t\t\t// Send the form data to the server.\n\t}\n\n\tsubmitContactForm({\n\t\t\temail: 'ex@mple.com',\n\t\t\tmessage: 'Hi! Could you tell me more about…',\n\t});\n\n\t// TypeScript error: missing property 'message'\n\tsubmitContactForm({\n\t\t\temail: 'ex@mple.com',\n\t});\n\t```\n\t
\n\n- [`Readonly`](https://www.typescriptlang.org/docs/handbook/utility-types.html#readonlytype) - Make all properties in `T` readonly.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#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)\n\n\t```ts\n\tenum LogLevel {\n\t\t\tOff,\n\t\t\tDebug,\n\t\t\tError,\n\t\t\tFatal\n\t};\n\n\tinterface LoggerConfig {\n\t\t\tname: string;\n\t\t\tlevel: LogLevel;\n\t}\n\n\tclass Logger {\n\t\t\tconfig: Readonly;\n\n\t\t\tconstructor({name, level}: LoggerConfig) {\n\t\t\t\t\tthis.config = {name, level};\n\t\t\t\t\tObject.freeze(this.config);\n\t\t\t}\n\t}\n\n\tconst config: LoggerConfig = {\n\t\tname: 'MyApp',\n\t\tlevel: LogLevel.Debug\n\t};\n\n\tconst logger = new Logger(config);\n\n\t// TypeScript Error: cannot assign to read-only property.\n\tlogger.config.level = LogLevel.Error;\n\n\t// We are able to edit config variable as we please.\n\tconfig.level = LogLevel.Error;\n\t```\n\t
\n\n- [`Pick`](https://www.typescriptlang.org/docs/handbook/utility-types.html#picktype-keys) - From `T`, pick a set of properties whose keys are in the union `K`.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#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)\n\n\t```ts\n\tinterface Article {\n\t\t\ttitle: string;\n\t\t\tthumbnail: string;\n\t\t\tcontent: string;\n\t}\n\n\t// Creates new type out of the `Article` interface composed\n\t// from the Articles' two properties: `title` and `thumbnail`.\n\t// `ArticlePreview = {title: string; thumbnail: string}`\n\ttype ArticlePreview = Pick;\n\n\t// Render a list of articles using only title and description.\n\tfunction renderArticlePreviews(previews: ArticlePreview[]): HTMLElement {\n\t\t\tconst articles = document.createElement('div');\n\n\t\t\tfor (const preview of previews) {\n\t\t\t\t\t// Append preview to the articles.\n\t\t\t}\n\n\t\t\treturn articles;\n\t}\n\n\tconst articles = renderArticlePreviews([\n\t\t\t{\n\t\t\t\ttitle: 'TypeScript tutorial!',\n\t\t\t\tthumbnail: '/assets/ts.jpg'\n\t\t\t}\n\t]);\n\t```\n\t
\n\n- [`Record`](https://www.typescriptlang.org/docs/handbook/utility-types.html#recordkeys-type) - Construct a type with a set of properties `K` of type `T`.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#code/AQ4ejYAUHsGcCWAXBMB2dgwGbAKYC2ADgDYwCeeemCaWArgE7ADGMxAhmuQHQBQoYEnJE8wALKEARnkaxEKdMAC8wAOS0kstGuAAfdQBM8ANzxlRjXQbVaWACwC0JPB0NqA3HwGgIwAJJoWozYHCxixnAsjAhStADmwESMMJYo1Fi4HMCIaPEu+MRklHj8gpqyoeHAAKJFFFTAAN4+giDYCIxwSAByHAR4AFw5SDF5Xm2gJBzdfQPD3WPxE5PAlBxdAPLYNQAelgh4aOHDaPQEMowrIAC+3oJ+AMKMrlrAXFhSAFZ4LEhC9g4-0BmA4JBISXgiCkBQABpILrJ5MhUGhYcATGD6Bk4Hh-jNgABrPDkOBlXyQAAq9ngYmJpOAAHcEOCRjAXqwYODfoo6DhakUSph+Uh7GI4P0xER4Cj0OSQGwMP8tP1hgAlX7swwAHgRl2RvIANALSA08ABtAC6AD4VM1Wm0Kow0MMrYaHYJjGYLLJXZb3at1HYnC43Go-QHQDcvA6-JsmEJXARgCDgMYWAhjIYhDAU+YiMAAFIwex0ZmilMITCGF79TLAGRsAgJYAAZRwSEZGzEABFTOZUrJ5Yn+jwnWgeER6HB7AAKJrADpdXqS4ZqYultTG6azVfqHswPBbtauLY7fayQ7HIbAAAMwBuAEoYw9IBq2Ixs9h2eFMOQYPQObALQKJgggABeYhghCIpikkKRpOQRIknAsZUiIeCttECBEP8NSMCkjDDAARMGziuIYxHwYOjDCMBmDNnAuTxA6irdCOBB1Lh5Dqpqn66tISIykawBnOCtqqC0gbjqc9DgpGkxegOliyfJDrRkAA)\n\n\t```ts\n\t// Positions of employees in our company.\n\ttype MemberPosition = 'intern' | 'developer' | 'tech-lead';\n\n\t// Interface describing properties of a single employee.\n\tinterface Employee {\n\t\t\tfirstName: string;\n\t\t\tlastName: string;\n\t\t\tyearsOfExperience: number;\n\t}\n\n\t// Create an object that has all possible `MemberPosition` values set as keys.\n\t// Those keys will store a collection of Employees of the same position.\n\tconst team: Record = {\n\t\t\tintern: [],\n\t\t\tdeveloper: [],\n\t\t\t'tech-lead': [],\n\t};\n\n\t// Our team has decided to help John with his dream of becoming Software Developer.\n\tteam.intern.push({\n\t\tfirstName: 'John',\n\t\tlastName: 'Doe',\n\t\tyearsOfExperience: 0\n\t});\n\n\t// `Record` forces you to initialize all of the property keys.\n\t// TypeScript Error: \"tech-lead\" property is missing\n\tconst teamEmpty: Record = {\n\t\t\tintern: null,\n\t\t\tdeveloper: null,\n\t};\n\t```\n\t
\n\n- [`Exclude`](https://www.typescriptlang.org/docs/handbook/utility-types.html#excludetype-excludedunion) - Exclude from `T` those types that are assignable to `U`.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#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)\n\n\t```ts\n\tinterface ServerConfig {\n\t\tport: null | string | number;\n\t}\n\n\ttype RequestHandler = (request: Request, response: Response) => void;\n\n\t// Exclude `null` type from `null | string | number`.\n\t// In case the port is equal to `null`, we will use default value.\n\tfunction getPortValue(port: Exclude): number {\n\t\tif (typeof port === 'string') {\n\t\t\treturn parseInt(port, 10);\n\t\t}\n\n\t\treturn port;\n\t}\n\n\tfunction startServer(handler: RequestHandler, config: ServerConfig): void {\n\t\tconst server = require('http').createServer(handler);\n\n\t\tconst port = config.port === null ? 3000 : getPortValue(config.port);\n\t\tserver.listen(port);\n\t}\n\t```\n\t
\n\n- [`Extract`](https://www.typescriptlang.org/docs/handbook/utility-types.html#extracttype-union) - Extract from `T` those types that are assignable to `U`.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#code/CYUwxgNghgTiAEAzArgOzAFwJYHtXzSwEdkQBJYACgEoAueVZAWwCMQYBuAKDDwGcM8MgBF4AXngBlAJ6scESgHIRi6ty5ZUGdoihgEABXZ888AN5d48ANoiAuvUat23K6ihMQ9ATE0BzV3goPy8GZjZOLgBfLi4Aejj4AEEICBwAdz54MAALKFQQ+BxEeAAHY1NgKAwoIKy0grr4DByEUpgccpgMaXgAaxBerCzi+B9-ZulygDouFHRsU1z8kKMYE1RhaqgAHkt4AHkWACt4EAAPbVRgLLWNgBp9gGlBs8uQa6yAUUuYPQwdgNpKM7nh7mMML4CgA+R5WABqUAgpDeVxuhxO1he0jsXGh8EoOBO9COx3BQPo2PBADckaR6IjkSA6PBqTgsMBzPsicdrEC7OJWXSQNwYvFEgAVTS9JLXODpeDpKBZFg4GCoWa8VACIJykAKiQWKy2YQOAioYikCg0OEMDyhRSy4DyxS24KhAAMjyi6gS8AAwjh5OD0iBFHAkJoEOksC1mnkMJq8gUQKDNttKPlnfrwYp3J5XfBHXqoKpfYkAOI4ansTxaeDADmoRSCCBYAbxhC6TDx6rwYHIRX5bScjA4bLJwoDmDwDkfbA9JMrVMVdM1TN69LgkTgwgkchUahqIA)\n\n\t```ts\n\tdeclare function uniqueId(): number;\n\n\tconst ID = Symbol('ID');\n\n\tinterface Person {\n\t\t[ID]: number;\n\t\tname: string;\n\t\tage: number;\n\t}\n\n\t// Allows changing the person data as long as the property key is of string type.\n\tfunction changePersonData<\n\t\tObj extends Person,\n\t\tKey extends Extract,\n\t\tValue extends Obj[Key]\n\t> (obj: Obj, key: Key, value: Value): void {\n\t\tobj[key] = value;\n\t}\n\n\t// Tiny Andrew was born.\n\tconst andrew = {\n\t\t[ID]: uniqueId(),\n\t\tname: 'Andrew',\n\t\tage: 0,\n\t};\n\n\t// Cool, we're fine with that.\n\tchangePersonData(andrew, 'name', 'Pony');\n\n\t// Government didn't like the fact that you wanted to change your identity.\n\tchangePersonData(andrew, ID, uniqueId());\n\t```\n\t
\n\n- [`NonNullable`](https://www.typescriptlang.org/docs/handbook/utility-types.html#nonnullabletype) - Exclude `null` and `undefined` from `T`.\n\t
\n\t\n\t\t\tExample\n\t\n\tWorks with strictNullChecks set to true.\n\n\t[Playground](https://typescript-play.js.org/?target=6#code/C4TwDgpgBACg9gJ2AOQK4FsBGEFQLxQDOwCAlgHYDmUAPlORtrnQwDasDcAUFwPQBU-WAEMkUOADMowqAGNWwwoSgATCBIqlgpOOSjAAFsOBRSy1IQgr9cKJlSlW1mZYQA3HFH68u8xcoBlHA8EACEHJ08Aby4oKDBUTFZSWXjEFEYcAEIALihkXTR2YSSIAB54JDQsHAA+blj4xOTUsHSACkMzPKD3HHDHNQQAGjSkPMqMmoQASh7g-oihqBi4uNIpdraxPAI2VhmVxrX9AzMAOm2ppnwoAA4ABifuE4BfKAhWSyOTuK7CS7pao3AhXF5rV48E4ICDAVAIPT-cGQyG+XTEIgLMJLTx7CAAdygvRCA0iCHaMwarhJOIQjUBSHaACJHk8mYdeLwxtdcVAAOSsh58+lXdr7Dlcq7A3n3J4PEUdADMcspUE53OluAIUGVTx46oAKuAIAFZGQwCYAKIIBCILjUxaDHAMnla+iodjcIA)\n\n\t```ts\n\ttype PortNumber = string | number | null;\n\n\t/** Part of a class definition that is used to build a server */\n\tclass ServerBuilder {\n\t\t\tportNumber!: NonNullable;\n\n\t\t\tport(this: ServerBuilder, port: PortNumber): ServerBuilder {\n\t\t\t\t\tif (port == null) {\n\t\t\t\t\t\t\tthis.portNumber = 8000;\n\t\t\t\t\t} else {\n\t\t\t\t\t\t\tthis.portNumber = port;\n\t\t\t\t\t}\n\n\t\t\t\t\treturn this;\n\t\t\t}\n\t}\n\n\tconst serverBuilder = new ServerBuilder();\n\n\tserverBuilder\n\t\t\t.port('8000') // portNumber = '8000'\n\t\t\t.port(null) // portNumber = 8000\n\t\t\t.port(3000); // portNumber = 3000\n\n\t// TypeScript error\n\tserverBuilder.portNumber = null;\n\t```\n\t
\n\n- [`Parameters`](https://www.typescriptlang.org/docs/handbook/utility-types.html#parameterstype) - Obtain the parameters of a function type in a tuple.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#code/GYVwdgxgLglg9mABAZwBYmMANgUwBQxgAOIUAXIgIZgCeA2gLoCUFAbnDACaIDeAUIkQB6IYgCypSlBxUATrMo1ECsJzgBbLEoipqAc0J7EMKMgDkiHLnU4wp46pwAPHMgB0fAL58+oSLARECEosLAA5ABUYG2QAHgAxJGdpVWREPDdMylk9ZApqemZEAF4APipacrw-CApEgBogkKwAYThwckQwEHUAIxxZJl4BYVEImiIZKF0oZRwiWVdbeygJmThgOYgcGFYcbhqApCJsyhtpWXcR1cnEePBoeDAABVPzgbTixFeFd8uEsClADcIxGiygIFkSEOT3SmTc2VydQeRx+ZxwF2QQ34gkEwDgsnSuFmMBKiAADEDjIhYk1Qm0OlSYABqZnYka4xA1DJZHJYkGc7yCbyeRA+CAIZCzNAYbA4CIAdxg2zJwVCkWirjwMswuEaACYmCCgA)\n\n\t```ts\n\tfunction shuffle(input: any[]): void {\n\t\t// Mutate array randomly changing its' elements indexes.\n\t}\n\n\tfunction callNTimes any> (func: Fn, callCount: number) {\n\t\t// Type that represents the type of the received function parameters.\n\t\ttype FunctionParameters = Parameters;\n\n\t\treturn function (...arguments_: FunctionParameters) {\n\t\t\tfor (let i = 0; i < callCount; i++) {\n\t\t\t\tfunc(...arguments_);\n\t\t\t}\n\t\t}\n\t}\n\n\tconst shuffleTwice = callNTimes(shuffle, 2);\n\t```\n\t
\n\n- [`ConstructorParameters`](https://www.typescriptlang.org/docs/handbook/utility-types.html#constructorparameterstype) - Obtain the parameters of a constructor function type in a tuple.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#code/MYGwhgzhAECCBOAXAlqApgWQPYBM0mgG8AoaaFRENALmgkXmQDsBzAblOmCycTV4D8teo1YdO3JiICuwRFngAKClWENmLAJRFOZRAAtkEAHQq00ALzlklNBzIBfYk+KhIMAJJTEYJsDQAwmDA+mgAPAAq0GgAHnxMODCKTGgA7tCKxllg8CwQtL4AngDaALraFgB80EWa1SRkAA6MAG5gfNAB4FABPDJyCrQR9tDNyG0dwMGhtBhgjWEiGgA00F70vv4RhY3hEZXVVinpc42KmuJkkv3y8Bly8EPaDWTkhiZd7r3e8LK3llwGCMXGQWGhEOsfH5zJlsrl8p0+gw-goAAo5MAAW3BaHgEEilU0tEhmzQ212BJ0ry4SOg+kg+gBBiMximIGA0nAfAQLGk2N4EAAEgzYcYcnkLsRdDTvNEYkYUKwSdCme9WdM0MYwYhFPSIPpJdTkAAzDKxBUaZX+aAAQgsVmkCTQxuYaBw2ng4Ok8CYcotSu8pMur09iG9vuObxZnx6SN+AyUWTF8MN0CcZE4Ywm5jZHK5aB5fP4iCFIqT4oRRTKRLo6lYVNeAHpG50wOzOe1zHr9NLQ+HoABybsD4HOKXXRA1JCoKhBELmI5pNaB6Fz0KKBAodDYPAgSUTmqYsAALx4m5nC6nW9nGq14KtaEUA9gR9PvuNCjQ9BgACNvcwNBtAcLiAA)\n\n\t```ts\n\tclass ArticleModel {\n\t\ttitle: string;\n\t\tcontent?: string;\n\n\t\tconstructor(title: string) {\n\t\t\tthis.title = title;\n\t\t}\n\t}\n\n\tclass InstanceCache any)> {\n\t\tprivate ClassConstructor: T;\n\t\tprivate cache: Map> = new Map();\n\n\t\tconstructor (ctr: T) {\n\t\t\tthis.ClassConstructor = ctr;\n\t\t}\n\n\t\tgetInstance (...arguments_: ConstructorParameters): InstanceType {\n\t\t\tconst hash = this.calculateArgumentsHash(...arguments_);\n\n\t\t\tconst existingInstance = this.cache.get(hash);\n\t\t\tif (existingInstance !== undefined) {\n\t\t\t\treturn existingInstance;\n\t\t\t}\n\n\t\t\treturn new this.ClassConstructor(...arguments_);\n\t\t}\n\n\t\tprivate calculateArgumentsHash(...arguments_: any[]): string {\n\t\t\t// Calculate hash.\n\t\t\treturn 'hash';\n\t\t}\n\t}\n\n\tconst articleCache = new InstanceCache(ArticleModel);\n\tconst amazonArticle = articleCache.getInstance('Amazon forests burning!');\n\t```\n\t
\n\n- [`ReturnType`](https://www.typescriptlang.org/docs/handbook/utility-types.html#returntypetype) - Obtain the return type of a function type.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#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-YhAA+qegAAYLKQLQj3ZsEsdccmnGcLor2Dn8xGedHGpEIBzEzspfsfMHDNAANTQACMVaIljV5GQkRA5DYmIpVKQAgAJARO9le33BDXIyi0YuLW2nJFGLqkOvxFB0YPdBSaLZ0IwNzyPkO8-xkGgsLh8Al427a3hWAhXwwHA8EHT5PmgAB1bAQBAANJ24adKWpft72RaBUTgRBUCAj89HAM8xCTaBjggABRQx0DuHJv25P9dCkWRZVIAAiBjoFImpmjlFBgA0NpsjadByDacgIDAEAIAAQmYpjoGYgAZSBsmGPw6DtZiiFA8CoJguDmAQmoZ2QvtUKQLdoAYmBTwgdEiCAA)\n\n\t```ts\n\t/** Provides every element of the iterable `iter` into the `callback` function and stores the results in an array. */\n\tfunction mapIter<\n\t\t\tElem,\n\t\t\tFunc extends (elem: Elem) => any,\n\t\t\tRet extends ReturnType\n\t>(iter: Iterable, callback: Func): Ret[] {\n\t\t\tconst mapped: Ret[] = [];\n\n\t\t\tfor (const elem of iter) {\n\t\t\t\t\tmapped.push(callback(elem));\n\t\t\t}\n\n\t\t\treturn mapped;\n\t}\n\n\tconst setObject: Set = new Set();\n\tconst mapObject: Map = new Map();\n\n\tmapIter(setObject, (value: string) => value.indexOf('Foo')); // number[]\n\n\tmapIter(mapObject, ([key, value]: [number, string]) => {\n\t\t\treturn key % 2 === 0 ? value : 'Odd';\n\t}); // string[]\n\t```\n\t
\n\n- [`InstanceType`](https://www.typescriptlang.org/docs/handbook/utility-types.html#instancetypetype) - Obtain the instance type of a constructor function type.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#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-YhAA+qegAAYLKQLQj3ZsEsdccmnGcLor2Dn8xGedHGpEIBzEzspfsfMHDNAANTQACMVaIljV5GQkRA5DYmIpVKQAgAJARO9le33BDXIyi0YuLW2nJFGLqkOvxFB0YPdBSaLZ0IwNzyPkO8-xkGgsLh8Al427a3hWAhXwwHA8EHT5PmgAB1bAQBAANJ24adKWpft72RaBUTgRBUCAj89HAM8xCTaBjggABRQx0DuHJv25P9dCkWRZVIAAiBjoFImpmjlFBgA0NpsjadByDacgIDAEAIAAQmYpjoGYgAZSBsmGPw6DtZiiFA8CoJguDmAQmoZ2QvtUKQLdoAYmBTwgdEiCAA)\n\n\t```ts\n\tclass IdleService {\n\t\t\tdoNothing (): void {}\n\t}\n\n\tclass News {\n\t\t\ttitle: string;\n\t\t\tcontent: string;\n\n\t\t\tconstructor(title: string, content: string) {\n\t\t\t\t\tthis.title = title;\n\t\t\t\t\tthis.content = content;\n\t\t\t}\n\t}\n\n\tconst instanceCounter: Map = new Map();\n\n\tinterface Constructor {\n\t\t\tnew(...arguments_: any[]): any;\n\t}\n\n\t// Keep track how many instances of `Constr` constructor have been created.\n\tfunction getInstance<\n\t\t\tConstr extends Constructor,\n\t\t\tArguments extends ConstructorParameters\n\t>(constructor: Constr, ...arguments_: Arguments): InstanceType {\n\t\t\tlet count = instanceCounter.get(constructor) || 0;\n\n\t\t\tconst instance = new constructor(...arguments_);\n\n\t\t\tinstanceCounter.set(constructor, count + 1);\n\n\t\t\tconsole.log(`Created ${count + 1} instances of ${Constr.name} class`);\n\n\t\t\treturn instance;\n\t}\n\n\n\tconst idleService = getInstance(IdleService);\n\t// Will log: `Created 1 instances of IdleService class`\n\tconst newsEntry = getInstance(News, 'New ECMAScript proposals!', 'Last month...');\n\t// Will log: `Created 1 instances of News class`\n\t```\n\t
\n\n- [`Omit`](https://www.typescriptlang.org/docs/handbook/utility-types.html#omittype-keys) - Constructs a type by picking all properties from T and then removing K.\n\t
\n\t\n\t\t\tExample\n\t\n\n\t[Playground](https://typescript-play.js.org/?target=6#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-SgfXlHqVUE4xiAA)\n\n\t```ts\n\tinterface Animal {\n\t\t\timageUrl: string;\n\t\t\tspecies: string;\n\t\t\timages: string[];\n\t\t\tparagraphs: string[];\n\t}\n\n\t// Creates new type with all properties of the `Animal` interface\n\t// except 'images' and 'paragraphs' properties. We can use this\n\t// type to render small hover tooltip for a wiki entry list.\n\ttype AnimalShortInfo = Omit;\n\n\tfunction renderAnimalHoverInfo (animals: AnimalShortInfo[]): HTMLElement {\n\t\t\tconst container = document.createElement('div');\n\t\t\t// Internal implementation.\n\t\t\treturn container;\n\t}\n\t```\n\t
\n\n- [`Uppercase`](https://www.typescriptlang.org/docs/handbook/utility-types.html#uppercasestringtype) - Transforms every character in a string into uppercase.\n\t
\n\t\n\t\tExample\n\t\n\n\t```ts\n\ttype T = Uppercase<'hello'>; // 'HELLO'\n\n\ttype T2 = Uppercase<'foo' | 'bar'>; // 'FOO' | 'BAR'\n\n\ttype T3 = Uppercase<`aB${S}`>;\n\ttype T4 = T3<'xYz'>; // 'ABXYZ'\n\n\ttype T5 = Uppercase; // string\n\ttype T6 = Uppercase; // any\n\ttype T7 = Uppercase; // never\n\ttype T8 = Uppercase<42>; // Error, type 'number' does not satisfy the constraint 'string'\n\t```\n\t
\n\n- [`Lowercase`](https://www.typescriptlang.org/docs/handbook/utility-types.html#lowercasestringtype) - Transforms every character in a string into lowercase.\n\t
\n\t\n\t\tExample\n\t\n\n\t```ts\n\ttype T = Lowercase<'HELLO'>; // 'hello'\n\n\ttype T2 = Lowercase<'FOO' | 'BAR'>; // 'foo' | 'bar'\n\n\ttype T3 = Lowercase<`aB${S}`>;\n\ttype T4 = T3<'xYz'>; // 'abxyz'\n\n\ttype T5 = Lowercase; // string\n\ttype T6 = Lowercase; // any\n\ttype T7 = Lowercase; // never\n\ttype T8 = Lowercase<42>; // Error, type 'number' does not satisfy the constraint 'string'\n\t```\n\t
\n\n- [`Capitalize`](https://www.typescriptlang.org/docs/handbook/utility-types.html#capitalizestringtype) - Transforms the first character in a string into uppercase.\n\t
\n\t\n\t\tExample\n\t\n\n\t```ts\n\ttype T = Capitalize<'hello'>; // 'Hello'\n\n\ttype T2 = Capitalize<'foo' | 'bar'>; // 'Foo' | 'Bar'\n\n\ttype T3 = Capitalize<`aB${S}`>;\n\ttype T4 = T3<'xYz'>; // 'ABxYz'\n\n\ttype T5 = Capitalize; // string\n\ttype T6 = Capitalize; // any\n\ttype T7 = Capitalize; // never\n\ttype T8 = Capitalize<42>; // Error, type 'number' does not satisfy the constraint 'string'\n\t```\n\t
\n\n- [`Uncapitalize`](https://www.typescriptlang.org/docs/handbook/utility-types.html#uncapitalizestringtype) - Transforms the first character in a string into lowercase.\n\t
\n\t\n\t\tExample\n\t\n\n\t```ts\n\ttype T = Uncapitalize<'Hello'>; // 'hello'\n\n\ttype T2 = Uncapitalize<'Foo' | 'Bar'>; // 'foo' | 'bar'\n\n\ttype T3 = Uncapitalize<`AB${S}`>;\n\ttype T4 = T3<'xYz'>; // 'aBxYz'\n\n\ttype T5 = Uncapitalize; // string\n\ttype T6 = Uncapitalize; // any\n\ttype T7 = Uncapitalize; // never\n\ttype T8 = Uncapitalize<42>; // Error, type 'number' does not satisfy the constraint 'string'\n\t```\n\t
\n\nYou can find some examples in the [TypeScript docs](https://www.typescriptlang.org/docs/handbook/utility-types.html).\n\n## Maintainers\n\n- [Sindre Sorhus](https://github.com/sindresorhus)\n- [Haozheng Li](https://github.com/Emiyaaaaa)\n- [Som Shekhar Mukherjee](https://github.com/som-sm)\n- [Jarek Radosz](https://github.com/CvX)\n- [Dimitri Benin](https://github.com/BendingBender)\n- [Pelle Wessman](https://github.com/voxpelli)\n- [Sébastien Mischler](https://github.com/skarab42)\n\n## License\n\n- [MIT](license-mit)\n- [CC0-1.0](license-cc0)\n\nSPDX-License-Identifier: (MIT OR CC0-1.0)\n" }, { "path": "source/all-extend.d.ts", "content": "import type {CollapseRestElement} from './internal/array.d.ts';\nimport type {ApplyDefaultOptions} from './internal/object.d.ts';\nimport type {IfNotAnyOrNever, Not} from './internal/type.d.ts';\nimport type {IsAny} from './is-any.d.ts';\nimport type {IsNever} from './is-never.d.ts';\nimport type {Or} from './or.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\n\n/**\n@see {@link AllExtend}\n*/\nexport type AllExtendOptions = {\n\t/**\n\tConsider `never` elements to match the target type only if the target type itself is `never` (or `any`).\n\n\t- When set to `true` (default), `never` is _not_ treated as a bottom type, instead, it is treated as a type that matches only itself (or `any`).\n\t- When set to `false`, `never` is treated as a bottom type, and behaves as it normally would.\n\n\t@default true\n\n\t@example\n\t```\n\timport type {AllExtend} from 'type-fest';\n\n\ttype A = AllExtend<[1, 2, never], number, {strictNever: true}>;\n\t//=> false\n\n\ttype B = AllExtend<[1, 2, never], number, {strictNever: false}>;\n\t//=> true\n\n\ttype C = AllExtend<[never, never], never, {strictNever: true}>;\n\t//=> true\n\n\ttype D = AllExtend<[never, never], never, {strictNever: false}>;\n\t//=> true\n\n\ttype E = AllExtend<['a', 'b', never], any, {strictNever: true}>;\n\t//=> true\n\n\ttype F = AllExtend<['a', 'b', never], any, {strictNever: false}>;\n\t//=> true\n\n\ttype G = AllExtend<[never, 1], never, {strictNever: true}>;\n\t//=> false\n\n\ttype H = AllExtend<[never, 1], never, {strictNever: false}>;\n\t//=> false\n\t```\n\t*/\n\tstrictNever?: boolean;\n};\n\ntype DefaultAllExtendOptions = {\n\tstrictNever: true;\n};\n\n/**\nReturns a boolean for whether every element in an array type extends another type.\n\n@example\n```\nimport type {AllExtend} from 'type-fest';\n\ntype A = AllExtend<[1, 2, 3], number>;\n//=> true\n\ntype B = AllExtend<[1, 2, '3'], number>;\n//=> false\n\ntype C = AllExtend<[number, number | string], number>;\n//=> boolean\n\ntype D = AllExtend<[true, boolean, true], true>;\n//=> boolean\n```\n\nNote: Behaviour of optional elements depend on the `exactOptionalPropertyTypes` compiler option. When the option is disabled, the target type must include `undefined` for a successful match.\n\n```\n// @exactOptionalPropertyTypes: true\nimport type {AllExtend} from 'type-fest';\n\ntype A = AllExtend<[1?, 2?, 3?], number>;\n//=> true\n```\n\n```\n// @exactOptionalPropertyTypes: false\nimport type {AllExtend} from 'type-fest';\n\ntype A = AllExtend<[1?, 2?, 3?], number>;\n//=> boolean\n\ntype B = AllExtend<[1?, 2?, 3?], number | undefined>;\n//=> true\n```\n\n@see {@link AllExtendOptions}\n\n@category Utilities\n@category Array\n*/\nexport type AllExtend =\n\t_AllExtend, Type, ApplyDefaultOptions>;\n\ntype _AllExtend> = IfNotAnyOrNever extends true\n\t\t\t? Or, IsAny>, Not> extends true\n\t\t\t\t// If target `Type` is also `never`, or is `any`, or `strictNever` is disabled, recurse further.\n\t\t\t\t? _AllExtend\n\t\t\t\t: false\n\t\t\t: First extends Type\n\t\t\t\t? _AllExtend\n\t\t\t\t: false\n\t\t: true,\n\tfalse, false>;\n\nexport {};\n" }, { "path": "source/all-union-fields.d.ts", "content": "import type {NonRecursiveType, ReadonlyKeysOfUnion, ValueOfUnion} from './internal/index.d.ts';\nimport type {KeysOfUnion} from './keys-of-union.d.ts';\nimport type {SharedUnionFields} from './shared-union-fields.d.ts';\nimport type {Simplify} from './simplify.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\n\n/**\nCreate a type with all fields from a union of object types.\n\nUse-cases:\n- You want a safe object type where each key exists in the union object.\n\n@example\n```\nimport type {AllUnionFields} from 'type-fest';\n\ntype Cat = {\n\tname: string;\n\ttype: 'cat';\n\tcatType: string;\n};\n\ntype Dog = {\n\tname: string;\n\ttype: 'dog';\n\tdogType: string;\n};\n\nfunction displayPetInfo(petInfo: Cat | Dog) {\n\t// typeof petInfo =>\n\t// {\n\t// \tname: string;\n\t// \ttype: 'cat';\n\t// \tcatType: string;\n\t// } | {\n\t// \tname: string;\n\t// \ttype: 'dog';\n\t// \tdogType: string;\n\t// }\n\n\tconsole.log('name:', petInfo.name);\n\tconsole.log('type:', petInfo.type);\n\n\t// TypeScript complains about `catType` and `dogType` not existing on type `Cat | Dog`.\n\t// @ts-expect-error\n\tconsole.log('animal type:', petInfo.catType ?? petInfo.dogType);\n}\n\nfunction displayPetInfoWithAllUnionFields(petInfo: AllUnionFields) {\n\t// typeof petInfo =>\n\t// {\n\t// \tname: string;\n\t// \ttype: 'cat' | 'dog';\n\t// \tcatType?: string;\n\t// \tdogType?: string;\n\t// }\n\n\tconsole.log('name:', petInfo.name);\n\tconsole.log('type:', petInfo.type);\n\n\t// No TypeScript error.\n\tconsole.log('animal type:', petInfo.catType ?? petInfo.dogType);\n}\n```\n\n@see {@link SharedUnionFields}\n\n@category Object\n@category Union\n*/\nexport type AllUnionFields =\nExtract | ReadonlySet | UnknownArray> extends infer SkippedMembers\n\t? Exclude extends infer RelevantMembers\n\t\t?\n\t\t| SkippedMembers\n\t\t| Simplify<\n\t\t// Include fields that are common in all union members\n\t\t\tSharedUnionFields &\n\t\t// Include readonly fields present in any union member\n\t\t\t{\n\t\t\t\treadonly [P in ReadonlyKeysOfUnion]?: ValueOfUnion>\n\t\t\t} &\n\t\t// Include remaining fields that are neither common nor readonly\n\t\t\t{\n\t\t\t\t[P in Exclude, ReadonlyKeysOfUnion | keyof RelevantMembers>]?: ValueOfUnion\n\t\t\t}\n\t\t>\n\t\t: never\n\t: never;\n\nexport {};\n" }, { "path": "source/and-all.d.ts", "content": "import type {AllExtend} from './all-extend.d.ts';\n\n/**\nReturns a boolean for whether all of the given elements are `true`.\n\nUse-cases:\n- Check if all conditions in a list of booleans are met.\n\n@example\n```\nimport type {AndAll} from 'type-fest';\n\ntype TTT = AndAll<[true, true, true]>;\n//=> true\n\ntype TTF = AndAll<[true, true, false]>;\n//=> false\n\ntype TFT = AndAll<[true, false, true]>;\n//=> false\n```\n\nNote: When `boolean` is passed as an element, it is distributed into separate cases, and the final result is a union of those cases.\nFor example, `AndAll<[true, boolean]>` expands to `AndAll<[true, true]> | AndAll<[true, false]>`, which simplifies to `true | false` (i.e., `boolean`).\n\n@example\n```\nimport type {AndAll} from 'type-fest';\n\ntype A = AndAll<[true, boolean]>;\n//=> boolean\n\ntype B = AndAll<[false, boolean]>;\n//=> false\n```\n\nNote: If any of the elements is `never`, the result becomes `false`.\n\n@example\n```\nimport type {AndAll} from 'type-fest';\n\ntype A = AndAll<[true, true, never]>;\n//=> false\n\ntype B = AndAll<[false, never, never]>;\n//=> false\n\ntype C = AndAll<[never, never, never]>;\n//=> false\n\ntype D = AndAll<[boolean, true, never]>;\n//=> false\n```\n\nNote: If `any` is passed as an element, it is treated as `boolean` and the result is computed accordingly.\n\n@example\n```\nimport type {AndAll} from 'type-fest';\n\ntype A = AndAll<[false, any]>;\n//=> false\n\ntype B = AndAll<[true, any]>;\n//=> boolean\n```\n\nNote: `AndAll<[]>` evaluates to `true` due to the concept of [vacuous truth](https://en.wikipedia.org/wiki/Logical_conjunction#:~:text=In%20keeping%20with%20the%20concept%20of%20vacuous%20truth%2C%20when%20conjunction%20is%20defined%20as%20an%20operator%20or%20function%20of%20arbitrary%20arity%2C%20the%20empty%20conjunction%20(AND%2Ding%20over%20an%20empty%20set%20of%20operands)%20is%20often%20defined%20as%20having%20the%20result%20true.), i.e., there are no `false` elements in an empty tuple.\n\n@see {@link And}\n@see {@link OrAll}\n*/\nexport type AndAll = AllExtend;\n\nexport {};\n" }, { "path": "source/and.d.ts", "content": "import type {AndAll} from './and-all.d.ts';\n\n/**\nReturns a boolean for whether two given types are both true.\n\nUse-case: Constructing complex conditional types where multiple conditions must be satisfied.\n\n@example\n```\nimport type {And} from 'type-fest';\n\ntype TT = And;\n//=> true\n\ntype TF = And;\n//=> false\n\ntype FT = And;\n//=> false\n\ntype FF = And;\n//=> false\n```\n\nNote: When `boolean` is passed as an argument, it is distributed into separate cases, and the final result is a union of those cases.\nFor example, `And` expands to `And | And`, which simplifies to `true | false` (i.e., `boolean`).\n\n@example\n```\nimport type {And} from 'type-fest';\n\ntype A = And;\n//=> boolean\n\ntype B = And;\n//=> boolean\n\ntype C = And;\n//=> false\n\ntype D = And;\n//=> false\n\ntype E = And;\n//=> boolean\n```\n\nNote: If either of the types is `never`, the result becomes `false`.\n\n@example\n```\nimport type {And} from 'type-fest';\n\ntype A = And;\n//=> false\n\ntype B = And;\n//=> false\n\ntype C = And;\n//=> false\n\ntype D = And;\n//=> false\n\ntype E = And;\n//=> false\n\ntype F = And;\n//=> false\n\ntype G = And;\n//=> false\n```\n\n@see {@link AndAll}\n@see {@link Or}\n@see {@link Xor}\n*/\nexport type And = AndAll<[A, B]>;\n\nexport {};\n" }, { "path": "source/array-element.d.ts", "content": "import type {UnknownArray} from './unknown-array.d.ts';\n\n/**\nExtracts the element type of an array or tuple.\n\nUse-cases:\n- When you need type-safe element extraction that returns `never` for non-arrays.\n- When extracting element types from generic array parameters in function signatures.\n- For better readability and explicit intent over using `T[number]` directly.\n\nNote: Returns `never` if the type is not an array.\n\n@example\n```\nimport type {ArrayElement} from 'type-fest';\n\n// Arrays\ntype StringArray = ArrayElement;\n//=> string\n\n// Tuples\ntype Tuple = ArrayElement<[1, 2, 3]>;\n//=> 1 | 2 | 3\n\n// Type-safe\ntype NotArray = ArrayElement<{a: string}>;\n//=> never\n\n// Practical example\ndeclare function getRandomElement(array: T): ArrayElement;\n\ngetRandomElement(['foo', 'bar', 'baz'] as const);\n//=> 'foo' | 'bar' | 'baz'\n```\n\n@see {@link ArrayValues} - For directly extracting values from a constant array type.\n@see {@link IterableElement} - For iterables like `Set`, `Map`, and generators (not suitable for all use cases due to different inference behavior).\n\n@category Array\n*/\nexport type ArrayElement =\n\tT extends UnknownArray\n\t\t? T[number]\n\t\t: never;\n\nexport {};\n" }, { "path": "source/array-indices.d.ts", "content": "/**\nProvides valid indices for a constant array or tuple.\n\nUse-case: This type is useful when working with constant arrays or tuples and you want to enforce type-safety for accessing elements by their indices.\n\n@example\n```\nimport type {ArrayIndices, ArrayValues} from 'type-fest';\n\nconst weekdays = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday'] as const;\n\ntype Weekday = ArrayIndices;\ntype WeekdayName = ArrayValues;\n\nconst getWeekdayName = (day: Weekday): WeekdayName => weekdays[day];\n```\n\n@see {@link ArrayValues}\n\n@category Array\n*/\nexport type ArrayIndices =\n\tExclude['length'], Element['length']>;\n\nexport {};\n" }, { "path": "source/array-length.d.ts", "content": "/**\nReturn the length of an array. Equivalent to `T['length']` where `T` extends any array.\n\nTuples resolve to numeric literals, while non-tuples resolve to the `number` type.\n\n@example\n```\nimport type {ArrayLength} from 'type-fest';\n\ntype TupleLength = ArrayLength<[1, 2, 3]>;\n//=> 3\n\ntype TupleWithOptionalMembersLength = ArrayLength<[1, 2, number?]>;\n//=> 2 | 3\n\ntype NonTupleArrayLength = ArrayLength;\n//=> number\n\ntype TupleWithRestElementLength = ArrayLength<[1, 2, ...string[]]>;\n//=> number\n\n// Distinguish between arrays with fixed and non-fixed lengths\ntype IsFixedLengthArray = number extends ArrayLength ? false : true;\n\ntype A = IsFixedLengthArray;\n//=> false\n\ntype B = IsFixedLengthArray<[1, 2, 3]>;\n//=> true\n```\n\n@category Array\n*/\nexport type ArrayLength = T['length'];\n\nexport {};\n" }, { "path": "source/array-reverse.d.ts", "content": "import type {If} from './if.d.ts';\nimport type {IsArrayReadonly} from './internal/array.d.ts';\nimport type {IfNotAnyOrNever, IsExactOptionalPropertyTypesEnabled} from './internal/type.d.ts';\nimport type {IsOptionalKeyOf} from './is-optional-key-of.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\n\n/**\nReverse the order of elements in a tuple type.\n\n@example\n```ts\nimport type {ArrayReverse} from 'type-fest';\n\ntype A = ArrayReverse<[string, number, boolean]>;\n//=> [boolean, number, string]\n\ntype B = ArrayReverse;\n//=> readonly [...boolean[], number, string]\n\ntype C = ArrayReverse<['foo', 'bar'] | readonly [1, 2, 3]>;\n//=> ['bar', 'foo'] | readonly [3, 2, 1]\n\ntype D = ArrayReverse;\n//=> string[]\n\ntype E = ArrayReverse<[]>;\n//=> []\n```\n\nNote: If the tuple contains optional elements, the result will be a union of tuples, refer to the examples below:\n\n@example\n```ts\nimport type {ArrayReverse} from 'type-fest';\n\ntype A = ArrayReverse<[string, number, boolean?]>;\n//=> [number, string] | [boolean, number, string]\n\ntype B = ArrayReverse<[string, number?, boolean?]>;\n//=> [string] | [number, string] | [boolean, number, string]\n\ntype C = ArrayReverse<[string?, number?, boolean?]>;\n//=> [] | [string] | [number, string] | [boolean, number, string]\n\ntype D = ArrayReverse<[string, number?, ...boolean[]]>;\n//=> [string] | [...boolean[], number, string]\n\ntype E = ArrayReverse<[string?, number?, ...boolean[]]>;\n//=> [] | [string] | [...boolean[], number, string]\n```\n\n@category Array\n*/\nexport type ArrayReverse = IfNotAnyOrNever extends infer Result\n\t\t\t? If, Readonly, Result>\n\t\t\t: never // Should never happen\n\t\t: never>; // Should never happen\n\ntype _ArrayReverse<\n\tTArray extends UnknownArray,\n\tBeforeRestAcc extends UnknownArray = [],\n\tAfterRestAcc extends UnknownArray = [],\n\tResult extends UnknownArray = never,\n> =\n\tkeyof TArray & `${number}` extends never\n\t\t// Enters this branch, if `TArray` is empty (e.g., `[]`),\n\t\t// or `TArray` contains no non-rest elements preceding the rest element (e.g., `[...string[]]` or `[...string[], string]`).\n\t\t? TArray extends readonly [...infer Rest, infer Last]\n\t\t\t? _ArrayReverse // Accumulate elements that are present after the rest element in reverse order.\n\t\t\t: Result | [...AfterRestAcc, ...TArray, ...BeforeRestAcc] // Add the rest element between the accumulated elements.\n\t\t: TArray extends readonly [(infer First)?, ...infer Rest]\n\t\t\t? IsOptionalKeyOf extends true\n\t\t\t\t? _ArrayReverse<\n\t\t\t\t\tRest,\n\t\t\t\t\t[First | (If), ...BeforeRestAcc], // Add `| undefined` for optional elements, if `exactOptionalPropertyTypes` is disabled.\n\t\t\t\t\tAfterRestAcc,\n\t\t\t\t\tResult | BeforeRestAcc\n\t\t\t\t>\n\t\t\t\t: _ArrayReverse\n\t\t\t: never; // Should never happen, since `readonly [(infer First)?, ...infer Rest]` is a top-type for arrays.\n\nexport {};\n" }, { "path": "source/array-slice.d.ts", "content": "import type {Sum} from './sum.d.ts';\nimport type {LessThanOrEqual} from './less-than-or-equal.d.ts';\nimport type {GreaterThanOrEqual} from './greater-than-or-equal.d.ts';\nimport type {GreaterThan} from './greater-than.d.ts';\nimport type {IsNegative} from './numeric.d.ts';\nimport type {Not, TupleMin} from './internal/index.d.ts';\nimport type {IsEqual} from './is-equal.d.ts';\nimport type {And} from './and.d.ts';\nimport type {ArraySplice} from './array-splice.d.ts';\nimport type {IsNever} from './is-never.d.ts';\n\n/**\nReturns an array slice of a given range, just like `Array#slice()`.\n\n@example\n```\nimport type {ArraySlice} from 'type-fest';\n\ntype T0 = ArraySlice<[0, 1, 2, 3, 4]>;\n//=> [0, 1, 2, 3, 4]\n\ntype T1 = ArraySlice<[0, 1, 2, 3, 4], 0, -1>;\n//=> [0, 1, 2, 3]\n\ntype T2 = ArraySlice<[0, 1, 2, 3, 4], 1, -2>;\n//=> [1, 2]\n\ntype T3 = ArraySlice<[0, 1, 2, 3, 4], -2, 4>;\n//=> [3]\n\ntype T4 = ArraySlice<[0, 1, 2, 3, 4], -2, -1>;\n//=> [3]\n\ntype T5 = ArraySlice<[0, 1, 2, 3, 4], 0, -999>;\n//=> []\n\nfunction arraySlice<\n\tconst Array_ extends readonly unknown[],\n\tStart extends number = 0,\n\tEnd extends number = Array_['length'],\n>(array: Array_, start?: Start, end?: End) {\n\treturn array.slice(start, end) as ArraySlice;\n}\n\nconst slice = arraySlice([1, '2', {a: 3}, [4, 5]], 0, -1);\n\ntype Slice = typeof slice;\n//=> [1, '2', {readonly a: 3}]\n\nconst value = slice[2].a;\n//=> 3\n\n// @ts-expect-error -- TS2493: Tuple type '[1, \"2\", {readonly a: 3}]' of length '3' has no element at index '3'.\nconst invalidIndexAccess = slice[3];\n```\n\n@category Array\n*/\nexport type ArraySlice<\n\tArray_ extends readonly unknown[],\n\tStart extends number = never,\n\tEnd extends number = never,\n> = Array_ extends unknown // To distributive type\n\t? IsNever extends true\n\t\t? IsNever extends true\n\t\t\t? _ArraySlice\n\t\t\t: End extends unknown // To distribute `End`\n\t\t\t\t? _ArraySlice\n\t\t\t\t: never // Never happens\n\t\t: IsNever extends true\n\t\t\t? Start extends unknown // To distribute `Start`\n\t\t\t\t? _ArraySlice\n\t\t\t\t: never // Never happens\n\t\t\t: Start extends unknown // To distribute `Start`\n\t\t\t\t? End extends unknown // To distribute `End`\n\t\t\t\t\t? _ArraySlice\n\t\t\t\t\t: never // Never happens\n\t\t\t\t: never // Never happens\n\t: never; // Never happens\n\ntype _ArraySlice<\n\tArray_ extends readonly unknown[],\n\tStart extends number = 0,\n\tEnd extends number = Array_['length'],\n> = And, IsEqual> extends true\n\t? Array_\n\t: number extends Array_['length']\n\t\t? VariableLengthArraySliceHelper\n\t\t: ArraySliceHelper extends true ? 0 : Start, IsEqual extends true ? Array_['length'] : End>;\n\ntype VariableLengthArraySliceHelper<\n\tArray_ extends readonly unknown[],\n\tStart extends number,\n\tEnd extends number,\n> = And>, IsEqual> extends true\n\t? ArraySplice\n\t: And<\n\t\tAnd>, Not>>,\n\t\tIsEqual, true>\n\t> extends true\n\t\t? ArraySliceByPositiveIndex\n\t\t: [];\n\ntype ArraySliceHelper<\n\tArray_ extends readonly unknown[],\n\tStart extends number = 0,\n\tEnd extends number = Array_['length'],\n\tTraversedElement extends Array = [],\n\tResult extends Array = [],\n\tArrayLength extends number = Array_['length'],\n\tPositiveS extends number = IsNegative extends true\n\t\t? Sum extends infer AddResult extends number\n\t\t\t? number extends AddResult // (ArrayLength + Start) < 0\n\t\t\t\t? 0\n\t\t\t\t: GreaterThan extends true ? AddResult : 0\n\t\t\t: never\n\t\t: Start,\n\tPositiveE extends number = IsNegative extends true ? Sum : End,\n> = true extends [IsNegative, LessThanOrEqual, GreaterThanOrEqual][number]\n\t? []\n\t: ArraySliceByPositiveIndex, TupleMin<[PositiveE, ArrayLength]>>;\n\ntype ArraySliceByPositiveIndex<\n\tArray_ extends readonly unknown[],\n\tStart extends number,\n\tEnd extends number,\n\tResult extends Array = [],\n> = Start extends End\n\t? Result\n\t: ArraySliceByPositiveIndex, End, [...Result, Array_[Start]]>;\n\nexport {};\n" }, { "path": "source/array-splice.d.ts", "content": "import type {StaticPartOfArray, VariablePartOfArray} from './internal/index.d.ts';\nimport type {GreaterThanOrEqual} from './greater-than-or-equal.d.ts';\nimport type {Subtract} from './subtract.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\nimport type {TupleOf} from './tuple-of.d.ts';\n\n/**\nThe implementation of `SplitArrayByIndex` for fixed length arrays.\n*/\ntype SplitFixedArrayByIndex =\nSplitIndex extends 0\n\t? [[], T]\n\t: T extends readonly [...TupleOf, ...infer V]\n\t\t? T extends readonly [...infer U, ...V]\n\t\t\t? [U, V]\n\t\t\t: [never, never]\n\t\t: [never, never];\n\n/**\nThe implementation of `SplitArrayByIndex` for variable length arrays.\n*/\ntype SplitVariableArrayByIndex['length']>,\n\tT2 = T1 extends number\n\t\t? TupleOf extends true ? T1 : number, VariablePartOfArray[number]>\n\t\t: [],\n> =\nSplitIndex extends 0\n\t? [[], T]\n\t: GreaterThanOrEqual['length'], SplitIndex> extends true\n\t\t? [\n\t\t\tSplitFixedArrayByIndex, SplitIndex>[0],\n\t\t\t[\n\t\t\t\t...SplitFixedArrayByIndex, SplitIndex>[1],\n\t\t\t\t...VariablePartOfArray,\n\t\t\t],\n\t\t]\n\t\t: [\n\t\t\t[\n\t\t\t\t...StaticPartOfArray,\n\t\t\t\t...(T2 extends UnknownArray ? T2 : []),\n\t\t\t],\n\t\t\tVariablePartOfArray,\n\t\t];\n\n/**\nSplit the given array `T` by the given `SplitIndex`.\n\n@example\n```\ntype A = SplitArrayByIndex<[1, 2, 3, 4], 2>;\n//=> [[1, 2], [3, 4]];\n\ntype B = SplitArrayByIndex<[1, 2, 3, 4], 0>;\n//=> [[], [1, 2, 3, 4]];\n```\n*/\ntype SplitArrayByIndex =\n\tSplitIndex extends 0\n\t\t? [[], T]\n\t\t: number extends T['length']\n\t\t\t? SplitVariableArrayByIndex\n\t\t\t: SplitFixedArrayByIndex;\n\n/**\nCreate a new array type by adding or removing elements at a specified index range in the original array.\n\nUse-case: Replace or insert items in an array type.\n\nLike [`Array#splice()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice) but for types.\n\n@example\n```\nimport type {ArraySplice} from 'type-fest';\n\ntype SomeMonths0 = ['January', 'April', 'June'];\ntype Months0 = ArraySplice;\n//=> ['January', 'Feb', 'March', 'April', 'June']\n\ntype SomeMonths1 = ['January', 'April', 'June'];\ntype Months1 = ArraySplice;\n//=> ['January', 'June']\n\ntype SomeMonths2 = ['January', 'Foo', 'April'];\ntype Months2 = ArraySplice;\n//=> ['January', 'Feb', 'March', 'April']\n```\n\n@category Array\n*/\nexport type ArraySplice<\n\tT extends UnknownArray,\n\tStart extends number,\n\tDeleteCount extends number,\n\tItems extends UnknownArray = [],\n> =\n\tSplitArrayByIndex extends [infer U extends UnknownArray, infer V extends UnknownArray]\n\t\t? SplitArrayByIndex extends [infer _Deleted extends UnknownArray, infer X extends UnknownArray]\n\t\t\t? [...U, ...Items, ...X]\n\t\t\t: never // Should never happen\n\t\t: never; // Should never happen\n\nexport {};\n" }, { "path": "source/array-tail.d.ts", "content": "import type {If} from './if.d.ts';\nimport type {IfNotAnyOrNever, IsArrayReadonly} from './internal/index.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\n\n/**\nExtract the type of an array or tuple minus the first element.\n\n@example\n```\nimport type {ArrayTail} from 'type-fest';\n\ntype A = ArrayTail<[1, 2, 3]>;\n//=> [2, 3]\n\ntype B = ArrayTail;\n//=> readonly [2, 3]\n\ntype C = ArrayTail<[1, 2, 3?, ...string[]]>;\n//=> [2, 3?, ...string[]]\n\ntype D = ArrayTail;\n//=> readonly []\n\ntype E = ArrayTail<[]>;\n//=> []\n\ntype F = ArrayTail;\n//=> string[]\n\ntype G = ArrayTail;\n//=> readonly [...string[], 1, 2]\n```\n\n@example\n```\nimport type {ArrayTail} from 'type-fest';\n\ntype Curry = Func extends (...agruments_: infer Arguments) => infer Return\n\t? Arguments extends readonly []\n\t\t? Return\n\t\t: (agrument: Arguments[0]) => Curry<(...agruments_: ArrayTail) => Return>\n\t: never;\n\ndeclare function curry(fn: Func): Curry;\n\ndeclare function searchBooks(genre: string, minRating: number, available: boolean): string[];\n\nconst availableTopSciFi = curry(searchBooks)('sci-fi')(4.5)(true);\n//=> string[]\n```\n\n@category Array\n*/\nexport type ArrayTail = IfNotAnyOrNever extends infer Result\n\t\t\t? If, Readonly, Result>\n\t\t\t: never // Should never happen\n\t\t: never\n>;\n\ntype _ArrayTail = TArray extends readonly [unknown?, ...infer Tail]\n\t? keyof TArray & `${number}` extends never\n\t\t? TArray extends readonly []\n\t\t\t? []\n\t\t\t: TArray // Happens when `TArray` is a non-tuple array (e.g., `string[]`) or has a leading rest element (e.g., `[...string[], number]`)\n\t\t: Tail\n\t: [];\n\nexport {};\n" }, { "path": "source/array-values.d.ts", "content": "/**\nProvides all values for a constant array or tuple.\n\nUse-case: This type is useful when working with constant arrays or tuples and you want to enforce type-safety with their values.\n\n@example\n```\nimport type {ArrayValues, ArrayIndices} from 'type-fest';\n\nconst weekdays = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday'] as const;\n\ntype WeekdayName = ArrayValues;\ntype Weekday = ArrayIndices;\n\nconst getWeekdayName = (day: Weekday): WeekdayName => weekdays[day];\n```\n\n@see {@link ArrayIndices}\n\n@category Array\n*/\nexport type ArrayValues = T[number];\n\nexport {};\n" }, { "path": "source/arrayable.d.ts", "content": "/**\nCreate a type that represents either the value or an array of the value.\n\n@see {@link Promisable}\n\n@example\n```\nimport type {Arrayable} from 'type-fest';\n\nfunction bundle(input: string, output: Arrayable) {\n\tconst outputList = Array.isArray(output) ? output : [output];\n\n\t// …\n\n\tfor (const output of outputList) {\n\t\tconsole.log(`write ${input} to: ${output}`);\n\t}\n}\n\nbundle('src/index.js', 'dist/index.js');\nbundle('src/index.js', ['dist/index.cjs', 'dist/index.mjs']);\n```\n\n@category Array\n*/\nexport type Arrayable =\n\tT\n// TODO: Use `readonly T[]` when this issue is resolved: https://github.com/microsoft/TypeScript/issues/17002\n\t| T[];\n\nexport {};\n" }, { "path": "source/async-return-type.d.ts", "content": "type AsyncFunction = (...arguments_: any[]) => PromiseLike;\n\n/**\nUnwrap the return type of a function that returns a `Promise`.\n\nThere has been [discussion](https://github.com/microsoft/TypeScript/pull/35998) about implementing this type in TypeScript.\n\n@example\n```ts\nimport type {AsyncReturnType} from 'type-fest';\n\ndeclare function asyncFunction(): Promise<{foo: string}>;\n\n// This type resolves to the unwrapped return type of `asyncFunction`.\ntype Value = AsyncReturnType;\n//=> {foo: string}\n\ndeclare function doSomething(value: Value): void;\n\nconst value = await asyncFunction();\ndoSomething(value);\n```\n\n@category Async\n*/\nexport type AsyncReturnType = Awaited>;\n\nexport {};\n" }, { "path": "source/asyncify.d.ts", "content": "import type {SetReturnType} from './set-return-type.d.ts';\n\n/**\nCreate an async version of the given function type, by boxing the return type in `Promise` while keeping the same parameter types.\n\nUse-case: You have two functions, one synchronous and one asynchronous that do the same thing. Instead of having to duplicate the type definition, you can use `Asyncify` to reuse the synchronous type.\n\n@example\n```\nimport type {Asyncify} from 'type-fest';\n\n// Synchronous function\ntype Config = {featureFlags: Record};\n\ndeclare function loadConfigSync(path: string): Config;\n\ntype LoadConfigAsync = Asyncify;\n//=> (path: string) => Promise\n```\n\n@category Async\n*/\nexport type Asyncify any> = SetReturnType>>>;\n\nexport {};\n" }, { "path": "source/basic.d.ts", "content": "/**\nMatches a [`class`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes).\n\n@category Class\n*/\nexport type Class = {\n\tprototype: Pick;\n\tnew(...arguments_: Arguments): T;\n};\n\n/**\nMatches a [`class` constructor](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes).\n\n@category Class\n*/\nexport type Constructor = new(...arguments_: Arguments) => T;\n\n/**\nMatches an [`abstract class`](https://www.typescriptlang.org/docs/handbook/2/classes.html#abstract-classes-and-members).\n\n@category Class\n\n@privateRemarks\nWe cannot use a `type` here because TypeScript throws: 'abstract' modifier cannot appear on a type member. (1070)\n*/\n// eslint-disable-next-line @typescript-eslint/consistent-type-definitions\nexport interface AbstractClass extends AbstractConstructor {\n\tprototype: Pick;\n}\n\n/**\nMatches an [`abstract class`](https://www.typescriptlang.org/docs/handbook/release-notes/typescript-4-2.html#abstract-construct-signatures) constructor.\n\n@category Class\n*/\nexport type AbstractConstructor = abstract new(...arguments_: Arguments) => T;\n\nexport {};\n" }, { "path": "source/camel-case.d.ts", "content": "import type {ApplyDefaultOptions} from './internal/index.d.ts';\nimport type {Words, WordsOptions} from './words.d.ts';\n\n/**\nCamelCase options.\n\n@see {@link CamelCase}\n*/\nexport type CamelCaseOptions = WordsOptions & {\n\t/**\n\tWhether to preserved consecutive uppercase letter.\n\n\t@default false\n\t*/\n\tpreserveConsecutiveUppercase?: boolean;\n};\n\nexport type _DefaultCamelCaseOptions = {\n\tsplitOnNumbers: true;\n\tpreserveConsecutiveUppercase: false;\n};\n\n/**\nConvert an array of words to camel-case.\n*/\ntype CamelCaseFromArray<\n\tWords extends string[],\n\tOptions extends Required,\n\tOutputString extends string = '',\n> = Words extends [\n\tinfer FirstWord extends string,\n\t...infer RemainingWords extends string[],\n]\n\t? Options['preserveConsecutiveUppercase'] extends true\n\t\t? `${Capitalize}${CamelCaseFromArray}`\n\t\t: `${Capitalize>}${CamelCaseFromArray}`\n\t: OutputString;\n\n/**\nConvert a string literal to camel-case.\n\nThis can be useful when, for example, converting some kebab-cased command-line flags or a snake-cased database result.\n\nBy default, consecutive uppercase letter are preserved. See {@link CamelCaseOptions.preserveConsecutiveUppercase preserveConsecutiveUppercase} option to change this behaviour.\n\n@example\n```\nimport type {CamelCase} from 'type-fest';\n\n// Simple\n\nconst someVariable: CamelCase<'foo-bar'> = 'fooBar';\nconst preserveConsecutiveUppercase: CamelCase<'foo-BAR-baz', {preserveConsecutiveUppercase: true}> = 'fooBARBaz';\n\n// Advanced\n\ntype CamelCasedProperties = {\n\t[K in keyof T as CamelCase]: T[K]\n};\n\ntype RawOptions = {\n\t'dry-run': boolean;\n\t'full_family_name': string;\n\tfoo: number;\n\tBAR: string;\n\tQUZ_QUX: number;\n\t'OTHER-FIELD': boolean;\n};\n\nconst dbResult: CamelCasedProperties = {\n\tdryRun: true,\n\tfullFamilyName: 'bar.js',\n\tfoo: 123,\n\tbar: 'foo',\n\tquzQux: 6,\n\totherField: false,\n};\n```\n\n@category Change case\n@category Template literal\n*/\nexport type CamelCase = Type extends string\n\t? string extends Type\n\t\t? Type\n\t\t: Uncapitalize ? Lowercase : Type, Options>,\n\t\t\tApplyDefaultOptions\n\t\t>>\n\t: Type;\n\nexport {};\n" }, { "path": "source/camel-cased-properties-deep.d.ts", "content": "import type {CamelCase, CamelCaseOptions, _DefaultCamelCaseOptions} from './camel-case.d.ts';\nimport type {ApplyDefaultOptions, NonRecursiveType} from './internal/index.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\n\n/**\nConvert object properties to camel case recursively.\n\nThis can be useful when, for example, converting some API types from a different style.\n\n@see {@link CamelCasedProperties}\n@see {@link CamelCase}\n\n@example\n```\nimport type {CamelCasedPropertiesDeep} from 'type-fest';\n\ntype User = {\n\tUserId: number;\n\tUserName: string;\n};\n\ntype UserWithFriends = {\n\tUserInfo: User;\n\tUserFriends: User[];\n};\n\nconst result: CamelCasedPropertiesDeep = {\n\tuserInfo: {\n\t\tuserId: 1,\n\t\tuserName: 'Tom',\n\t},\n\tuserFriends: [\n\t\t{\n\t\t\tuserId: 2,\n\t\t\tuserName: 'Jerry',\n\t\t},\n\t\t{\n\t\t\tuserId: 3,\n\t\t\tuserName: 'Spike',\n\t\t},\n\t],\n};\n\nconst preserveConsecutiveUppercase: CamelCasedPropertiesDeep<{fooBAR: {fooBARBiz: [{fooBARBaz: string}]}}, {preserveConsecutiveUppercase: true}> = {\n\tfooBAR: {\n\t\tfooBARBiz: [{\n\t\t\tfooBARBaz: 'string',\n\t\t}],\n\t},\n};\n```\n\n@category Change case\n@category Template literal\n@category Object\n*/\nexport type CamelCasedPropertiesDeep<\n\tValue,\n\tOptions extends CamelCaseOptions = {},\n> = _CamelCasedPropertiesDeep>;\n\ntype _CamelCasedPropertiesDeep<\n\tValue,\n\tOptions extends Required,\n> = Value extends NonRecursiveType\n\t? Value\n\t: Value extends UnknownArray\n\t\t? CamelCasedPropertiesArrayDeep\n\t\t: Value extends Set\n\t\t\t? Set<_CamelCasedPropertiesDeep>\n\t\t\t: Value extends object\n\t\t\t\t? {\n\t\t\t\t\t[K in keyof Value as CamelCase]: _CamelCasedPropertiesDeep;\n\t\t\t\t}\n\t\t\t\t: Value;\n\n// This is a copy of DelimiterCasedPropertiesArrayDeep (see: delimiter-cased-properties-deep.d.ts).\n// These types should be kept in sync.\ntype CamelCasedPropertiesArrayDeep<\n\tValue extends UnknownArray,\n\tOptions extends Required,\n> = Value extends []\n\t? []\n\t// Trailing spread array\n\t: Value extends [infer U, ...infer V]\n\t\t? [_CamelCasedPropertiesDeep, ..._CamelCasedPropertiesDeep]\n\t\t: Value extends readonly [infer U, ...infer V]\n\t\t\t? readonly [_CamelCasedPropertiesDeep, ..._CamelCasedPropertiesDeep]\n\t\t\t: // Leading spread array\n\t\t\tValue extends readonly [...infer U, infer V]\n\t\t\t\t? [..._CamelCasedPropertiesDeep, _CamelCasedPropertiesDeep]\n\t\t\t\t: // Array\n\t\t\t\tValue extends Array\n\t\t\t\t\t? Array<_CamelCasedPropertiesDeep>\n\t\t\t\t\t: Value extends ReadonlyArray\n\t\t\t\t\t\t? ReadonlyArray<_CamelCasedPropertiesDeep>\n\t\t\t\t\t\t: never;\n\nexport {};\n" }, { "path": "source/camel-cased-properties.d.ts", "content": "import type {CamelCase, CamelCaseOptions, _DefaultCamelCaseOptions} from './camel-case.d.ts';\nimport type {ApplyDefaultOptions} from './internal/index.d.ts';\n\n/**\nConvert object properties to camel case but not recursively.\n\nThis can be useful when, for example, converting some API types from a different style.\n\n@see {@link CamelCasedPropertiesDeep}\n@see {@link CamelCase}\n\n@example\n```\nimport type {CamelCasedProperties} from 'type-fest';\n\ntype User = {\n\tUserId: number;\n\tUserName: string;\n};\n\nconst result: CamelCasedProperties = {\n\tuserId: 1,\n\tuserName: 'Tom',\n};\n\nconst preserveConsecutiveUppercase: CamelCasedProperties<{fooBAR: string}, {preserveConsecutiveUppercase: true}> = {\n\tfooBAR: 'string',\n};\n```\n\n@category Change case\n@category Template literal\n@category Object\n*/\nexport type CamelCasedProperties = Value extends Function\n\t? Value\n\t: Value extends Array\n\t\t? Value\n\t\t: {\n\t\t\t[K in keyof Value as\n\t\t\tCamelCase>\n\t\t\t]: Value[K];\n\t\t};\n\nexport {};\n" }, { "path": "source/characters.d.ts", "content": "/**\nMatches any uppercase letter in the basic Latin alphabet (A-Z).\n\n@example\n```\nimport type {UppercaseLetter} from 'type-fest';\n\nconst a: UppercaseLetter = 'A'; // Valid\n// @ts-expect-error\nconst b: UppercaseLetter = 'a'; // Invalid\n// @ts-expect-error\nconst c: UppercaseLetter = 'AB'; // Invalid\n```\n\n@category Type\n*/\nexport type UppercaseLetter = 'A' | 'B' | 'C' | 'D' | 'E' | 'F' | 'G' | 'H' | 'I' | 'J' | 'K' | 'L' | 'M' | 'N' | 'O' | 'P' | 'Q' | 'R' | 'S' | 'T' | 'U' | 'V' | 'W' | 'X' | 'Y' | 'Z';\n\n/**\nMatches any lowercase letter in the basic Latin alphabet (a-z).\n\n@example\n```\nimport type {LowercaseLetter} from 'type-fest';\n\nconst a: LowercaseLetter = 'a'; // Valid\n// @ts-expect-error\nconst b: LowercaseLetter = 'A'; // Invalid\n```\n\n@category Type\n*/\nexport type LowercaseLetter = 'a' | 'b' | 'c' | 'd' | 'e' | 'f' | 'g' | 'h' | 'i' | 'j' | 'k' | 'l' | 'm' | 'n' | 'o' | 'p' | 'q' | 'r' | 's' | 't' | 'u' | 'v' | 'w' | 'x' | 'y' | 'z';\n\n/**\nMatches any digit as a string ('0'-'9').\n\n@example\n```\nimport type {DigitCharacter} from 'type-fest';\n\nconst a: DigitCharacter = '0'; // Valid\n// @ts-expect-error\nconst b: DigitCharacter = 0; // Invalid\n```\n\n@category Type\n*/\nexport type DigitCharacter = '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9';\n\n/**\nMatches any lowercase letter (a-z), uppercase letter (A-Z), or digit ('0'-'9') in the basic Latin alphabet.\n\n@example\n```\nimport type {Alphanumeric} from 'type-fest';\n\nconst a: Alphanumeric = 'A'; // Valid\n// @ts-expect-error\nconst b: Alphanumeric = '#'; // Invalid\n```\n\n@category Type\n*/\nexport type Alphanumeric = LowercaseLetter | UppercaseLetter | DigitCharacter;\n\nexport {};\n" }, { "path": "source/conditional-except.d.ts", "content": "import type {Except} from './except.d.ts';\nimport type {ConditionalKeys} from './conditional-keys.d.ts';\n\n/**\nExclude keys from a shape that matches the given `Condition`.\n\nThis is useful when you want to create a new type with a specific set of keys from a shape. For example, you might want to exclude all the primitive properties from a class and form a new shape containing everything but the primitive properties.\n\n@example\n```\nimport type {Primitive, ConditionalExcept} from 'type-fest';\n\nclass Awesome {\n\tconstructor(public name: string, public successes: number, public failures: bigint) {}\n\n\trun() {\n\t\t// do something\n\t}\n}\n\ntype ExceptPrimitivesFromAwesome = ConditionalExcept;\n//=> {run: () => void}\n```\n\n@example\n```\nimport type {ConditionalExcept} from 'type-fest';\n\ntype Example = {\n\ta: string;\n\tb: string | number;\n\tc: () => void;\n\td: {};\n};\n\ntype NonStringKeysOnly = ConditionalExcept;\n//=> {b: string | number; c: () => void; d: {}}\n```\n\n@category Object\n*/\nexport type ConditionalExcept = Except<\n\tBase,\n\tConditionalKeys\n>;\n\nexport {};\n" }, { "path": "source/conditional-keys.d.ts", "content": "import type {ExtendsStrict} from './extends-strict.d.ts';\nimport type {IfNotAnyOrNever} from './internal/type.d.ts';\nimport type {TupleToObject} from './tuple-to-object.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\n\n/**\nExtract the keys from a type where the value type of the key extends the given `Condition`.\n\nInternally this is used for the `ConditionalPick` and `ConditionalExcept` types.\n\n@example\n```\nimport type {ConditionalKeys} from 'type-fest';\n\ntype Example = {\n\ta: string;\n\tb: string | number;\n\tc?: string;\n\td: {};\n};\n\ntype StringKeysOnly = ConditionalKeys;\n//=> 'a'\n```\n\nNote: To extract optional keys, make sure your `Condition` is a union of `undefined` (for example, `string | undefined`) as demonstrated below.\n\n@example\n```\nimport type {ConditionalKeys} from 'type-fest';\n\ntype StringKeysAndUndefined = ConditionalKeys<{a?: string}, string | undefined>;\n//=> 'a'\n\ntype NoMatchingKeys = ConditionalKeys<{a?: string}, string>;\n//=> never\n```\n\nYou can also extract array indices whose value match the specified condition, as shown below:\n```\nimport type {ConditionalKeys} from 'type-fest';\n\ntype StringValueIndices = ConditionalKeys<[string, number, string], string>;\n//=> '0' | '2'\n\ntype NumberValueIndices = ConditionalKeys<[string, number?, string?], number | undefined>;\n//=> '1'\n```\n\n@category Object\n*/\nexport type ConditionalKeys = (Base extends UnknownArray ? TupleToObject : Base) extends infer _Base // Remove non-numeric keys from arrays\n\t? IfNotAnyOrNever<_Base, _ConditionalKeys<_Base, Condition>, keyof _Base>\n\t: never;\n\ntype _ConditionalKeys = keyof {\n\t[\n\tKey in (keyof Base & {}) as // `& {}` prevents homomorphism\n\tExtendsStrict extends true ? Key : never\n\t]: never\n};\n\nexport {};\n" }, { "path": "source/conditional-pick-deep.d.ts", "content": "import type {IsEqual} from './is-equal.d.ts';\nimport type {ConditionalExcept} from './conditional-except.d.ts';\nimport type {ConditionalSimplifyDeep} from './conditional-simplify-deep.d.ts';\nimport type {UnknownRecord} from './unknown-record.d.ts';\nimport type {EmptyObject} from './empty-object.d.ts';\nimport type {ApplyDefaultOptions, IsPlainObject} from './internal/index.d.ts';\n\n/**\nUsed to mark properties that should be excluded.\n*/\ndeclare const conditionalPickDeepSymbol: unique symbol;\n\n/**\nAssert the condition according to the {@link ConditionalPickDeepOptions.condition|condition} option.\n*/\ntype AssertCondition = Options['condition'] extends 'equality'\n\t? IsEqual\n\t: Type extends Condition\n\t\t? true\n\t\t: false;\n\n/**\nConditionalPickDeep options.\n\n@see {@link ConditionalPickDeep}\n*/\nexport type ConditionalPickDeepOptions = {\n\t/**\n\tThe condition assertion mode.\n\n\t@default 'extends'\n\t*/\n\tcondition?: 'extends' | 'equality';\n};\n\ntype DefaultConditionalPickDeepOptions = {\n\tcondition: 'extends';\n};\n\n/**\nPick keys recursively from the shape that matches the given condition.\n\n@see {@link ConditionalPick}\n\n@example\n```\nimport type {ConditionalPickDeep} from 'type-fest';\n\ntype Example = {\n\ta: string;\n\tb: string | boolean;\n\tc: {\n\t\td: string;\n\t\te: {\n\t\t\tf?: string;\n\t\t\tg?: boolean;\n\t\t\th: string | boolean;\n\t\t\ti: boolean | bigint;\n\t\t};\n\t\tj: boolean;\n\t};\n};\n\ntype StringPick = ConditionalPickDeep;\n//=> {a: string; c: {d: string}}\n\ntype StringPickOptional = ConditionalPickDeep;\n//=> {a: string; c: {d: string; e: {f?: string}}}\n\ntype StringPickOptionalOnly = ConditionalPickDeep;\n//=> {c: {e: {f?: string}}}\n\ntype BooleanPick = ConditionalPickDeep;\n//=> {c: {e: {g?: boolean}; j: boolean}}\n\ntype NumberPick = ConditionalPickDeep;\n//=> never\n\ntype StringOrBooleanPick = ConditionalPickDeep;\n//=> {\n// \ta: string;\n// \tb: string | boolean;\n// \tc: {\n// \t\td: string;\n// \t\te: {\n// \t\t\th: string | boolean;\n// \t\t};\n// \t\tj: boolean;\n// \t};\n// }\n\ntype StringOrBooleanPickOnly = ConditionalPickDeep;\n//=> {b: string | boolean; c: {e: {h: string | boolean}}}\n```\n\n@category Object\n*/\nexport type ConditionalPickDeep<\n\tType,\n\tCondition,\n\tOptions extends ConditionalPickDeepOptions = {},\n> = _NeverIfEmpty<_ConditionalPickDeep<\n\tType,\n\tCondition,\n\tApplyDefaultOptions\n>>;\n\ntype _NeverIfEmpty = Type extends EmptyObject ? never : Type;\n\ntype _ConditionalPickDeep<\n\tType,\n\tCondition,\n\tOptions extends Required,\n> = ConditionalSimplifyDeep extends true\n\t\t? Type[Key]\n\t\t: IsPlainObject extends true\n\t\t\t? _ConditionalPickDeep\n\t\t\t: typeof conditionalPickDeepSymbol;\n}, (typeof conditionalPickDeepSymbol | undefined) | EmptyObject>, never, UnknownRecord>;\n\nexport {};\n" }, { "path": "source/conditional-pick.d.ts", "content": "import type {ConditionalKeys} from './conditional-keys.d.ts';\nimport type {IsNever} from './is-never.d.ts';\n\n/**\nPick keys from the shape that matches the given `Condition`.\n\nThis is useful when you want to create a new type from a specific subset of an existing type. For example, you might want to pick all the primitive properties from a class and form a new automatically derived type.\n\n@example\n```\nimport type {Primitive, ConditionalPick} from 'type-fest';\n\nclass Awesome {\n\tconstructor(public name: string, public successes: number, public failures: bigint) {}\n\n\trun() {\n\t\t// do something\n\t}\n}\n\ntype PickPrimitivesFromAwesome = ConditionalPick;\n//=> {name: string; successes: number; failures: bigint}\n```\n\n@example\n```\nimport type {ConditionalPick} from 'type-fest';\n\ntype Example = {\n\ta: string;\n\tb: string | number;\n\tc: () => void;\n\td: {};\n};\n\ntype StringKeysOnly = ConditionalPick;\n//=> {a: string}\n```\n\n@category Object\n*/\nexport type ConditionalPick = ConditionalKeys extends infer Keys\n\t? IsNever extends true\n\t\t? never\n\t\t: Pick\n\t: never;\n\nexport {};\n" }, { "path": "source/conditional-simplify-deep.d.ts", "content": "/**\nRecursively simplifies a type while including and/or excluding certain types from being simplified.\n\n@example\n```\nimport type {ConditionalSimplifyDeep} from 'type-fest';\n\ntype TypeA = {\n\tfoo: {\n\t\ta: string;\n\t};\n};\n\ntype TypeB = {\n\tfoo: {\n\t\tb: string;\n\t};\n};\n\ntype SimplifyDeepTypeAB = ConditionalSimplifyDeep;\n//=> {foo: {a: string; b: string}}\n```\n\n@example\n```\nimport type {ConditionalSimplifyDeep} from 'type-fest';\n\ntype SomeComplexType1 = {\n\ta1: string;\n\tb1: number;\n\tc1: boolean;\n};\n\ntype SomeComplexType2 = {\n\ta2: string;\n\tb2: number;\n\tc2: boolean;\n};\n\ntype TypeA = {\n\tfoo: {\n\t\ta: string;\n\t\tcomplexType: SomeComplexType1;\n\t};\n};\n\ntype TypeB = {\n\tfoo: {\n\t\tb: string;\n\t\tcomplexType: SomeComplexType2;\n\t};\n};\n\ntype SimplifyDeepTypeAB = ConditionalSimplifyDeep;\n//=> {\n// \tfoo: {\n// \t\ta: string;\n// \t\tcomplexType: SomeComplexType1 & SomeComplexType2;\n// \t\tb: string;\n// \t};\n// }\n```\n\n@see {@link SimplifyDeep}\n@category Object\n*/\nexport type ConditionalSimplifyDeep = Type extends ExcludeType\n\t? Type\n\t: Type extends IncludeType\n\t\t? {[TypeKey in keyof Type]: ConditionalSimplifyDeep}\n\t\t: Type;\n\nexport {};\n" }, { "path": "source/conditional-simplify.d.ts", "content": "/**\nSimplifies a type while including and/or excluding certain types from being simplified.\n\nUseful to improve type hints shown in editors. And also to transform an `interface` into a `type` to aid with assignability.\n\n@example\n```\nimport type {ConditionalSimplify} from 'type-fest';\n\ntype TypeA = {\n\ta: string;\n};\n\ntype TypeB = {\n\tb: string;\n};\n\ntype TypeAB = TypeA & TypeB;\n//=> TypeA & TypeB\n\ntype SimplifyTypeAB = ConditionalSimplify;\n//=> {a: string; b: string}\n```\n\n@example\n```\nimport type {ConditionalSimplify} from 'type-fest';\n\ntype Simplify = ConditionalSimplify | Map | unknown[], object>;\n\ntype A = Simplify & Set>;\n//=> Set & Set\n\ntype B = Simplify & Map>;\n//=> Map & Map\n\ntype C = Simplify<{a: number} & {b: string}>;\n//=> {a: number; b: string}\n```\n\n@see {@link ConditionalSimplifyDeep}\n@category Object\n*/\nexport type ConditionalSimplify = Type extends ExcludeType\n\t? Type\n\t: Type extends IncludeType\n\t\t? {[TypeKey in keyof Type]: Type[TypeKey]}\n\t\t: Type;\n\nexport {};\n" }, { "path": "source/delimiter-case.d.ts", "content": "import type {ApplyDefaultOptions, AsciiPunctuation, StartsWith} from './internal/index.d.ts';\nimport type {IsStringLiteral} from './is-literal.d.ts';\nimport type {Merge} from './merge.d.ts';\nimport type {RemovePrefix} from './remove-prefix.d.ts';\nimport type {_DefaultWordsOptions, Words, WordsOptions} from './words.d.ts';\n\nexport type _DefaultDelimiterCaseOptions = Merge<_DefaultWordsOptions, {splitOnNumbers: false}>;\n\n/**\nConvert an array of words to delimiter case starting with a delimiter with input capitalization.\n*/\ntype DelimiterCaseFromArray<\n\tWords extends string[],\n\tDelimiter extends string,\n\tOutputString extends string = '',\n> = Words extends [\n\tinfer FirstWord extends string,\n\t...infer RemainingWords extends string[],\n]\n\t? DelimiterCaseFromArray extends true ? '' : Delimiter\n\t}${FirstWord}`>\n\t: OutputString;\n\n/**\nConvert a string literal to a custom string delimiter casing.\n\nThis can be useful when, for example, converting a camel-cased object property to an oddly cased one.\n\n@see {@link KebabCase}\n@see {@link SnakeCase}\n\n@example\n```\nimport type {DelimiterCase} from 'type-fest';\n\n// Simple\n\nconst someVariable: DelimiterCase<'fooBar', '#'> = 'foo#bar';\nconst someVariableNoSplitOnNumbers: DelimiterCase<'p2pNetwork', '#', {splitOnNumbers: false}> = 'p2p#network';\n\n// Advanced\n\ntype OddlyCasedProperties = {\n\t[K in keyof T as DelimiterCase]: T[K]\n};\n\ntype SomeOptions = {\n\tdryRun: boolean;\n\tincludeFile: string;\n\tfoo: number;\n};\n\nconst rawCliOptions: OddlyCasedProperties = {\n\t'dry#run': true,\n\t'include#file': 'bar.js',\n\tfoo: 123,\n};\n```\n\n@category Change case\n@category Template literal\n */\nexport type DelimiterCase<\n\tValue,\n\tDelimiter extends string,\n\tOptions extends WordsOptions = {},\n> = Value extends string\n\t? IsStringLiteral extends false\n\t\t? Value\n\t\t: Lowercase>,\n\t\t\tDelimiter\n\t\t>, string, {strict: false}>>\n\t: Value;\n\nexport {};\n" }, { "path": "source/delimiter-cased-properties-deep.d.ts", "content": "import type {_DefaultDelimiterCaseOptions, DelimiterCase} from './delimiter-case.d.ts';\nimport type {ApplyDefaultOptions, NonRecursiveType} from './internal/index.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\nimport type {WordsOptions} from './words.d.ts';\n\n/**\nConvert object properties to delimiter case recursively.\n\nThis can be useful when, for example, converting some API types from a different style.\n\n@see {@link DelimiterCase}\n@see {@link DelimiterCasedProperties}\n\n@example\n```\nimport type {DelimiterCasedPropertiesDeep} from 'type-fest';\n\ntype User = {\n\tuserId: number;\n\tuserName: string;\n};\n\ntype UserWithFriends = {\n\tuserInfo: User;\n\tuserFriends: User[];\n};\n\nconst result: DelimiterCasedPropertiesDeep = {\n\t'user-info': {\n\t\t'user-id': 1,\n\t\t'user-name': 'Tom',\n\t},\n\t'user-friends': [\n\t\t{\n\t\t\t'user-id': 2,\n\t\t\t'user-name': 'Jerry',\n\t\t},\n\t\t{\n\t\t\t'user-id': 3,\n\t\t\t'user-name': 'Spike',\n\t\t},\n\t],\n};\n\nconst splitOnNumbers: DelimiterCasedPropertiesDeep<{line1: {line2: [{line3: string}]}}, '-', {splitOnNumbers: true}> = {\n\t'line-1': {\n\t\t'line-2': [\n\t\t\t{\n\t\t\t\t'line-3': 'string',\n\t\t\t},\n\t\t],\n\t},\n};\n```\n\n@category Change case\n@category Template literal\n@category Object\n*/\nexport type DelimiterCasedPropertiesDeep<\n\tValue,\n\tDelimiter extends string,\n\tOptions extends WordsOptions = {},\n> = _DelimiterCasedPropertiesDeep>;\n\ntype _DelimiterCasedPropertiesDeep<\n\tValue,\n\tDelimiter extends string,\n\tOptions extends Required,\n> = Value extends NonRecursiveType\n\t? Value\n\t: Value extends UnknownArray\n\t\t? DelimiterCasedPropertiesArrayDeep\n\t\t: Value extends Set\n\t\t\t? Set<_DelimiterCasedPropertiesDeep>\n\t\t\t: Value extends object\n\t\t\t\t? {\n\t\t\t\t\t[K in keyof Value as DelimiterCase]:\n\t\t\t\t\t_DelimiterCasedPropertiesDeep\n\t\t\t\t}\n\t\t\t\t: Value;\n\n// This is a copy of CamelCasedPropertiesArrayDeep (see: camel-cased-properties-deep.d.ts).\n// These types should be kept in sync.\ntype DelimiterCasedPropertiesArrayDeep<\n\tValue extends UnknownArray,\n\tDelimiter extends string,\n\tOptions extends Required,\n> = Value extends []\n\t? []\n\t// Trailing spread array\n\t:\tValue extends [infer U, ...infer V]\n\t\t? [_DelimiterCasedPropertiesDeep, ..._DelimiterCasedPropertiesDeep]\n\t\t: Value extends readonly [infer U, ...infer V]\n\t\t\t? readonly [_DelimiterCasedPropertiesDeep, ..._DelimiterCasedPropertiesDeep]\n\t\t\t// Leading spread array\n\t\t\t: Value extends [...infer U, infer V]\n\t\t\t\t? [..._DelimiterCasedPropertiesDeep, _DelimiterCasedPropertiesDeep]\n\t\t\t\t: Value extends readonly [...infer U, infer V]\n\t\t\t\t\t? readonly [..._DelimiterCasedPropertiesDeep, _DelimiterCasedPropertiesDeep]\n\t\t\t\t\t// Array\n\t\t\t\t\t: Value extends Array\n\t\t\t\t\t\t? Array<_DelimiterCasedPropertiesDeep>\n\t\t\t\t\t\t: Value extends ReadonlyArray\n\t\t\t\t\t\t\t? ReadonlyArray<_DelimiterCasedPropertiesDeep>\n\t\t\t\t\t\t\t: never;\n\nexport {};\n" }, { "path": "source/delimiter-cased-properties.d.ts", "content": "import type {_DefaultDelimiterCaseOptions, DelimiterCase} from './delimiter-case.d.ts';\nimport type {ApplyDefaultOptions} from './internal/index.d.ts';\nimport type {WordsOptions} from './words.d.ts';\n\n/**\nConvert object properties to delimiter case but not recursively.\n\nThis can be useful when, for example, converting some API types from a different style.\n\n@see {@link DelimiterCase}\n@see {@link DelimiterCasedPropertiesDeep}\n\n@example\n```\nimport type {DelimiterCasedProperties} from 'type-fest';\n\ntype User = {\n\tuserId: number;\n\tuserName: string;\n};\n\nconst result: DelimiterCasedProperties = {\n\t'user-id': 1,\n\t'user-name': 'Tom',\n};\n\nconst splitOnNumbers: DelimiterCasedProperties<{line1: string}, '-', {splitOnNumbers: true}> = {\n\t'line-1': 'string',\n};\n```\n\n@category Change case\n@category Template literal\n@category Object\n*/\nexport type DelimiterCasedProperties<\n\tValue,\n\tDelimiter extends string,\n\tOptions extends WordsOptions = {},\n> = Value extends Function\n\t? Value\n\t: Value extends Array\n\t\t? Value\n\t\t: {[K in keyof Value as\n\t\t\tDelimiterCase>\n\t\t\t]: Value[K]};\n\nexport {};\n" }, { "path": "source/distributed-omit.d.ts", "content": "import type {KeysOfUnion} from './keys-of-union.d.ts';\n\n/**\nOmits keys from a type, distributing the operation over a union.\n\nTypeScript's `Omit` doesn't distribute over unions, leading to the erasure of unique properties from union members when omitting keys. This creates a type that only retains properties common to all union members, making it impossible to access member-specific properties after the Omit. Essentially, using `Omit` on a union type merges the types into a less specific one, hindering type narrowing and property access based on discriminants. This type solves that.\n\nExample:\n\n```\ntype A = {\n\tdiscriminant: 'A';\n\tfoo: string;\n\ta: number;\n};\n\ntype B = {\n\tdiscriminant: 'B';\n\tfoo: string;\n\tb: string;\n};\n\ntype Union = A | B;\n\ntype OmittedUnion = Omit;\n//=> {discriminant: 'A' | 'B'}\n\ndeclare const omittedUnion: OmittedUnion;\n\nif (omittedUnion.discriminant === 'A') {\n\t// We would like to narrow `omittedUnion`'s type\n\t// to `A` here, but we can't because `Omit`\n\t// doesn't distribute over unions.\n\n\t// @ts-expect-error\n\tconst aValue = omittedUnion.a;\n\t// Error: `a` is not a property of `{discriminant: 'A' | 'B'}`\n}\n```\n\nWhile `Except` solves this problem, it restricts the keys you can omit to the ones that are present in **ALL** union members, where `DistributedOmit` allows you to omit keys that are present in **ANY** union member.\n\n@example\n```\nimport type {DistributedOmit} from 'type-fest';\n\ntype A = {\n\tdiscriminant: 'A';\n\tfoo: string;\n\ta: number;\n};\n\ntype B = {\n\tdiscriminant: 'B';\n\tfoo: string;\n\tbar: string;\n\tb: string;\n};\n\ntype C = {\n\tdiscriminant: 'C';\n\tbar: string;\n\tc: boolean;\n};\n\n// Notice that `foo` exists in `A` and `B`, but not in `C`, and\n// `bar` exists in `B` and `C`, but not in `A`.\n\ntype Union = A | B | C;\n\ntype OmittedUnion = DistributedOmit;\n\ndeclare const omittedUnion: OmittedUnion;\n\nif (omittedUnion.discriminant === 'A') {\n\tconst aValue = omittedUnion.a;\n\t// OK\n\n\t// @ts-expect-error\n\tconst fooValue = omittedUnion.foo;\n\t// Error: `foo` is not a property of `{discriminant: 'A'; a: string}`\n\n\t// @ts-expect-error\n\tconst barValue = omittedUnion.bar;\n\t// Error: `bar` is not a property of `{discriminant: 'A'; a: string}`\n}\n```\n\n@category Object\n*/\nexport type DistributedOmit> =\n\tObjectType extends unknown\n\t\t? Omit\n\t\t: never;\n\nexport {};\n" }, { "path": "source/distributed-pick.d.ts", "content": "import type {KeysOfUnion} from './keys-of-union.d.ts';\n\n/**\nPick keys from a type, distributing the operation over a union.\n\nTypeScript's `Pick` doesn't distribute over unions, leading to the erasure of unique properties from union members when picking keys. This creates a type that only retains properties common to all union members, making it impossible to access member-specific properties after the Pick. Essentially, using `Pick` on a union type merges the types into a less specific one, hindering type narrowing and property access based on discriminants. This type solves that.\n\nExample:\n\n```\ntype A = {\n\tdiscriminant: 'A';\n\tfoo: {\n\t\tbar: string;\n\t};\n};\n\ntype B = {\n\tdiscriminant: 'B';\n\tfoo: {\n\t\tbaz: string;\n\t};\n};\n\ntype Union = A | B;\n\ntype PickedUnion = Pick;\n//=> {discriminant: 'A' | 'B'; foo: {bar: string} | {baz: string}}\n\ndeclare const pickedUnion: PickedUnion;\n\nif (pickedUnion.discriminant === 'A') {\n\t// We would like to narrow `pickedUnion`'s type\n\t// to `A` here, but we can't because `Pick`\n\t// doesn't distribute over unions.\n\n\t// @ts-expect-error\n\tconst barValue = pickedUnion.foo.bar;\n\t// Error: Property 'bar' does not exist on type '{bar: string} | {baz: string}'.\n}\n```\n\n@example\n```\nimport type {DistributedPick} from 'type-fest';\n\ntype A = {\n\tdiscriminant: 'A';\n\tfoo: {\n\t\tbar: string;\n\t};\n\textraneous: boolean;\n};\n\ntype B = {\n\tdiscriminant: 'B';\n\tfoo: {\n\t\tbaz: string;\n\t};\n\textraneous: boolean;\n};\n\n// Notice that `foo.bar` exists in `A` but not in `B`.\n\ntype Union = A | B;\n\ntype PickedUnion = DistributedPick;\n\ndeclare const pickedUnion: PickedUnion;\n\nif (pickedUnion.discriminant === 'A') {\n\tconst barValue = pickedUnion.foo.bar;\n\t// OK\n\n\t// @ts-expect-error\n\tconst extraneousValue = pickedUnion.extraneous;\n\t// Error: Property `extraneous` does not exist on type `Pick`.\n\n\t// @ts-expect-error\n\tconst bazValue = pickedUnion.foo.baz;\n\t// Error: `bar` is not a property of `{discriminant: 'A'; a: string}`.\n}\n```\n\n@category Object\n*/\nexport type DistributedPick> =\n\tObjectType extends unknown\n\t\t? Pick>\n\t\t: never;\n\nexport {};\n" }, { "path": "source/empty-object.d.ts", "content": "declare const emptyObjectSymbol: unique symbol;\n\n/**\nRepresents a strictly empty plain object, the `{}` value.\n\nWhen you annotate something as the type `{}`, it can be anything except `null` and `undefined`. This means that you cannot use `{}` to represent an empty plain object ([read more](https://stackoverflow.com/questions/47339869/typescript-empty-object-and-any-difference/52193484#52193484)).\n\n@example\n```\nimport type {EmptyObject} from 'type-fest';\n\n// The following illustrates the problem with `{}`.\nconst foo1: {} = {}; // Pass\nconst foo2: {} = []; // Pass\nconst foo3: {} = 42; // Pass\nconst foo4: {} = {a: 1}; // Pass\n\n// With `EmptyObject` only the first case is valid.\nconst bar1: EmptyObject = {}; // Pass\n// @ts-expect-error\nconst bar2: EmptyObject = []; // Fail\n// @ts-expect-error\nconst bar3: EmptyObject = 42; // Fail\n// @ts-expect-error\nconst bar4: EmptyObject = {a: 1}; // Fail\n```\n\nUnfortunately, `Record`, `Record` and `Record` do not work. See {@link https://github.com/sindresorhus/type-fest/issues/395 #395}.\n\n@category Object\n*/\nexport type EmptyObject = {[emptyObjectSymbol]?: never};\n\n/**\nReturns a `boolean` for whether the type is strictly equal to an empty plain object, the `{}` value.\n\n@example\n```\nimport type {IsEmptyObject} from 'type-fest';\n\ntype Pass = IsEmptyObject<{}>; //=> true\ntype Fail1 = IsEmptyObject<[]>; //=> false\ntype Fail2 = IsEmptyObject; //=> false\n```\n\n@see {@link EmptyObject}\n@category Object\n*/\nexport type IsEmptyObject = T extends EmptyObject ? true : false;\n\nexport {};\n" }, { "path": "source/entries.d.ts", "content": "import type {_ArrayEntry, _MapEntry, _ObjectEntry, _SetEntry} from './entry.d.ts';\n\ntype ArrayEntries = Array<_ArrayEntry>;\ntype MapEntries = Array<_MapEntry>;\ntype ObjectEntries = Array<_ObjectEntry>;\ntype SetEntries> = Array<_SetEntry>;\n\n/**\nMany collections have an `entries` method which returns an array of a given object's own enumerable string-keyed property [key, value] pairs. The `Entries` type will return the type of that collection's entries.\n\nFor example the {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries|`Object`}, {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/entries|`Map`}, {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/entries|`Array`}, and {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/entries|`Set`} collections all have this method. Note that `WeakMap` and `WeakSet` do not have this method since their entries are not enumerable.\n\n@see `Entry` if you want to just access the type of a single entry.\n\n@example\n```\nimport type {Entries} from 'type-fest';\n\ntype Example = {\n\tsomeKey: number;\n};\n\nconst manipulatesEntries = (examples: Entries) => examples.map(example => [\n\t// Does some arbitrary processing on the key (with type information available)\n\texample[0].toUpperCase(),\n\n\t// Does some arbitrary processing on the value (with type information available)\n\texample[1].toFixed(0),\n]);\n\nconst example: Example = {someKey: 1};\nconst entries = Object.entries(example) as Entries;\nconst output = manipulatesEntries(entries);\n\n// Objects\nconst objectExample = {a: 1};\nconst objectEntries: Entries = [['a', 1]];\n\n// Arrays\nconst arrayExample = ['a', 1];\nconst arrayEntries: Entries = [[0, 'a'], [1, 1]];\n\n// Maps\nconst mapExample = new Map([['a', 1]]);\nconst mapEntries: Entries = [['a', 1]];\n\n// Sets\nconst setExample = new Set(['a', 1]);\nconst setEntries: Entries = [['a', 'a'], [1, 1]];\n```\n\n@category Object\n@category Map\n@category Set\n@category Array\n*/\nexport type Entries =\n\tBaseType extends Map ? MapEntries\n\t\t: BaseType extends Set ? SetEntries\n\t\t\t: BaseType extends readonly unknown[] ? ArrayEntries\n\t\t\t\t: BaseType extends object ? ObjectEntries\n\t\t\t\t\t: never;\n\nexport {};\n" }, { "path": "source/entry.d.ts", "content": "type MapKey = BaseType extends Map ? KeyType : never;\ntype MapValue = BaseType extends Map ? ValueType : never;\n\nexport type _ArrayEntry = [number, BaseType[number]];\nexport type _MapEntry = [MapKey, MapValue];\nexport type _ObjectEntry = [keyof BaseType, BaseType[keyof BaseType]];\nexport type _SetEntry = BaseType extends Set ? [ItemType, ItemType] : never;\n\n/**\nMany collections have an `entries` method which returns an array of a given object's own enumerable string-keyed property [key, value] pairs. The `Entry` type will return the type of that collection's entry.\n\nFor example the {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries|`Object`}, {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/entries|`Map`}, {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/entries|`Array`}, and {@link https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set/entries|`Set`} collections all have this method. Note that `WeakMap` and `WeakSet` do not have this method since their entries are not enumerable.\n\n@see `Entries` if you want to just access the type of the array of entries (which is the return of the `.entries()` method).\n\n@example\n```\nimport type {Entry} from 'type-fest';\n\ntype Example = {\n\tsomeKey: number;\n};\n\nconst manipulatesEntry = (example: Entry) => [\n\t// Does some arbitrary processing on the key (with type information available)\n\texample[0].toUpperCase(),\n\n\t// Does some arbitrary processing on the value (with type information available)\n\texample[1].toFixed(0),\n];\n\nconst example: Example = {someKey: 1};\nconst entry = Object.entries(example)[0] as Entry;\nconst output = manipulatesEntry(entry);\n\n// Objects\nconst objectExample = {a: 1};\nconst objectEntry: Entry = ['a', 1];\n\n// Arrays\nconst arrayExample = ['a', 1];\nconst arrayEntryString: Entry = [0, 'a'];\nconst arrayEntryNumber: Entry = [1, 1];\n\n// Maps\nconst mapExample = new Map([['a', 1]]);\nconst mapEntry: Entry = ['a', 1];\n\n// Sets\nconst setExample = new Set(['a', 1]);\nconst setEntryString: Entry = ['a', 'a'];\nconst setEntryNumber: Entry = [1, 1];\n```\n\n@category Object\n@category Map\n@category Array\n@category Set\n*/\nexport type Entry =\n\tBaseType extends Map ? _MapEntry\n\t\t: BaseType extends Set ? _SetEntry\n\t\t\t: BaseType extends readonly unknown[] ? _ArrayEntry\n\t\t\t\t: BaseType extends object ? _ObjectEntry\n\t\t\t\t\t: never;\n\nexport {};\n" }, { "path": "source/exact.d.ts", "content": "import type {ObjectValue} from './internal/index.d.ts';\nimport type {ArrayElement} from './array-element.d.ts';\nimport type {IsEqual} from './is-equal.d.ts';\nimport type {KeysOfUnion} from './keys-of-union.d.ts';\nimport type {IsUnknown} from './is-unknown.d.ts';\nimport type {Primitive} from './primitive.d.ts';\n\n/**\nCreate a type from `ParameterType` and `InputType` and change keys exclusive to `InputType` to `never`.\n- Generate a list of keys that exists in `InputType` but not in `ParameterType`.\n- Mark these excess keys as `never`.\n*/\ntype ExactObject = {[Key in keyof ParameterType]: Exact>}\n\t& Record>, never>;\n\n/**\nCreate a type that does not allow extra properties, meaning it only allows properties that are explicitly declared.\n\nThis is useful for function type-guarding to reject arguments with excess properties. Due to the nature of TypeScript, it does not complain if excess properties are provided unless the provided value is an object literal.\n\n*Please upvote [this issue](https://github.com/microsoft/TypeScript/issues/12936) if you want to have this type as a built-in in TypeScript.*\n\n@example\n```\ntype OnlyAcceptName = {name: string};\n\ndeclare function onlyAcceptName(arguments_: OnlyAcceptName): void;\n\n// TypeScript complains about excess properties when an object literal is provided.\n// @ts-expect-error\nonlyAcceptName({name: 'name', id: 1});\n// `id` is excess\n\n// TypeScript does not complain about excess properties when the provided value is a variable (not an object literal).\nconst invalidInput = {name: 'name', id: 1};\nonlyAcceptName(invalidInput); // No errors\n```\n\nHaving `Exact` allows TypeScript to reject excess properties.\n\n@example\n```\nimport type {Exact} from 'type-fest';\n\ntype OnlyAcceptName = {name: string};\n\ndeclare function onlyAcceptNameImproved>(arguments_: T): void;\n\nconst invalidInput = {name: 'name', id: 1};\n// @ts-expect-error\nonlyAcceptNameImproved(invalidInput); // Compilation error\n```\n\n[Read more](https://stackoverflow.com/questions/49580725/is-it-possible-to-restrict-typescript-object-to-contain-only-properties-defined)\n\n@category Utilities\n*/\nexport type Exact =\n\t// Before distributing, check if the two types are equal and if so, return the parameter type immediately\n\tIsEqual extends true ? ParameterType\n\t\t// If the parameter is a primitive, return it as is immediately to avoid it being converted to a complex type\n\t\t: ParameterType extends Primitive ? ParameterType\n\t\t\t// If the parameter is an unknown, return it as is immediately to avoid it being converted to a complex type\n\t\t\t: IsUnknown extends true ? unknown\n\t\t\t\t// If the parameter is a Function, return it as is because this type is not capable of handling function, leave it to TypeScript\n\t\t\t\t: ParameterType extends Function ? ParameterType\n\t\t\t\t\t// Convert union of array to array of union: A[] & B[] => (A & B)[]\n\t\t\t\t\t: ParameterType extends unknown[] ? Array, ArrayElement>>\n\t\t\t\t\t\t// In TypeScript, Array is a subtype of ReadonlyArray, so always test Array before ReadonlyArray.\n\t\t\t\t\t\t: ParameterType extends readonly unknown[] ? ReadonlyArray, ArrayElement>>\n\t\t\t\t\t\t\t: ExactObject;\n\nexport {};\n" }, { "path": "source/except.d.ts", "content": "import type {ApplyDefaultOptions} from './internal/index.d.ts';\nimport type {IsEqual} from './is-equal.d.ts';\n\n/**\nFilter out keys from an object.\n\nReturns `never` if `Exclude` is strictly equal to `Key`.\nReturns `never` if `Key` extends `Exclude`.\nReturns `Key` otherwise.\n\n@example\n```\ntype Filtered = Filter<'foo', 'foo'>;\n//=> never\n```\n\n@example\n```\ntype Filtered = Filter<'bar', string>;\n//=> never\n```\n\n@example\n```\ntype Filtered = Filter<'bar', 'foo'>;\n//=> 'bar'\n```\n\n@see {Except}\n*/\ntype Filter = IsEqual extends true ? never : (KeyType extends ExcludeType ? never : KeyType);\n\nexport type ExceptOptions = {\n\t/**\n\tDisallow assigning non-specified properties.\n\n\tNote that any omitted properties in the resulting type will be present in autocomplete as `undefined`.\n\n\t@default false\n\t*/\n\trequireExactProps?: boolean;\n};\n\ntype DefaultExceptOptions = {\n\trequireExactProps: false;\n};\n\n/**\nCreate a type from an object type without certain keys.\n\nWe recommend setting the `requireExactProps` option to `true`.\n\nThis type is a stricter version of [`Omit`](https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-5.html#the-omit-helper-type). The `Omit` type does not restrict the omitted keys to be keys present on the given type, while `Except` does. The benefits of a stricter type are avoiding typos and allowing the compiler to pick up on rename refactors automatically.\n\nThis type was proposed to the TypeScript team, which declined it, saying they prefer that libraries implement stricter versions of the built-in types ([microsoft/TypeScript#30825](https://github.com/microsoft/TypeScript/issues/30825#issuecomment-523668235)).\n\n@example\n```\nimport type {Except} from 'type-fest';\n\ntype Foo = {\n\ta: number;\n\tb: string;\n};\n\ntype FooWithoutA = Except;\n//=> {b: string}\n\n// @ts-expect-error\nconst fooWithoutA: FooWithoutA = {a: 1, b: '2'};\n// errors: 'a' does not exist in type '{ b: string; }'\n\ntype FooWithoutB = Except;\n//=> {a: number} & Partial>\n\n// @ts-expect-error\nconst fooWithoutB: FooWithoutB = {a: 1, b: '2'};\n// errors at 'b': Type 'string' is not assignable to type 'undefined'.\n\n// The `Omit` utility type doesn't work when omitting specific keys from objects containing index signatures.\n\n// Consider the following example:\n\ntype UserData = {\n\t[metadata: string]: string;\n\temail: string;\n\tname: string;\n\trole: 'admin' | 'user';\n};\n\n// `Omit` clearly doesn't behave as expected in this case:\ntype PostPayload = Omit;\n//=> {[x: string]: string; [x: number]: string}\n\n// In situations like this, `Except` works better.\n// It simply removes the `email` key while preserving all the other keys.\ntype PostPayloadFixed = Except;\n//=> {[x: string]: string; name: string; role: 'admin' | 'user'}\n```\n\n@category Object\n*/\nexport type Except =\n\t_Except>;\n\ntype _Except> = {\n\t[KeyType in keyof ObjectType as Filter]: ObjectType[KeyType];\n} & (Options['requireExactProps'] extends true\n\t? Partial>\n\t: {});\n\nexport {};\n" }, { "path": "source/exclude-exactly.d.ts", "content": "import type {IsNever} from './is-never.d.ts';\nimport type {IsAny} from './is-any.d.ts';\nimport type {If} from './if.d.ts';\nimport type {IsEqual} from './is-equal.d.ts';\nimport type {IfNotAnyOrNever} from './internal/type.d.ts';\n\n/**\nA stricter version of `Exclude` that excludes types only when they are exactly identical.\n\n@example\n```\nimport type {ExcludeExactly} from 'type-fest';\n\ntype TestExclude1 = Exclude<'a' | 'b' | 'c' | 1 | 2 | 3, string>;\n//=> 1 | 2 | 3\n\ntype TestExcludeExactly1 = ExcludeExactly<'a' | 'b' | 'c' | 1 | 2 | 3, string>;\n//=> 'a' | 'b' | 'c' | 1 | 2 | 3\n\ntype TestExclude2 = Exclude<'a' | 'b' | 'c' | 1 | 2 | 3, any>;\n//=> never\n\ntype TestExcludeExactly2 = ExcludeExactly<'a' | 'b' | 'c' | 1 | 2 | 3, any>;\n//=> 'a' | 'b' | 'c' | 1 | 2 | 3\n\ntype TestExclude3 = Exclude<{a: string} | {a: string; b: string}, {a: string}>;\n//=> never\n\ntype TestExcludeExactly3 = ExcludeExactly<{a: string} | {a: string; b: string}, {a: string}>;\n//=> {a: string; b: string}\n```\n\n@category Improved Built-in\n*/\nexport type ExcludeExactly =\n\tIfNotAnyOrNever<\n\t\tUnion,\n\t\t_ExcludeExactly,\n\t\t// If `Union` is `any`, then if `Delete` is `any`, return `never`, else return `Union`.\n\t\tIf, never, Union>,\n\t\t// If `Union` is `never`, then if `Delete` is `never`, return `never`, else return `Union`.\n\t\tIf, never, Union>\n\t>;\n\ntype _ExcludeExactly =\n\tIfNotAnyOrNever, true, never>\n\t\t\t\t: never] extends [never] ? Union : never\n\t\t\t: never,\n\t\t// If `Delete` is `any` or `never`, then return `Union`,\n\t\t// because `Union` cannot be `any` or `never` here.\n\t\tUnion, Union\n\t>;\n\nexport {};\n" }, { "path": "source/exclude-rest-element.d.ts", "content": "import type {SplitOnRestElement} from './split-on-rest-element.d.ts';\nimport type {IsArrayReadonly} from './internal/array.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\nimport type {IfNotAnyOrNever} from './internal/type.d.ts';\n\n/**\nCreate a tuple with the [`rest`](https://www.typescriptlang.org/docs/handbook/2/objects.html#tuple-types) element removed.\n\n@example\n```\nimport type {ExcludeRestElement} from 'type-fest';\n\ntype T1 = ExcludeRestElement<[number, ...string[], string, 'foo']>;\n//=> [number, string, 'foo']\n\ntype T2 = ExcludeRestElement<[...boolean[], string]>;\n//=> [string]\n\ntype T3 = ExcludeRestElement<[...Array<'foo'>, true]>;\n//=> [true]\n\ntype T4 = ExcludeRestElement<[number, string]>;\n//=> [number, string]\n```\n\n@see {@link ExtractRestElement}\n@see {@link SplitOnRestElement}\n@category Array\n*/\nexport type ExcludeRestElement = IfNotAnyOrNever extends infer Result\n\t\t? Result extends readonly UnknownArray[]\n\t\t\t? IsArrayReadonly extends true\n\t\t\t\t? Readonly<[...Result[0], ...Result[2]]>\n\t\t\t\t: [...Result[0], ...Result[2]]\n\t\t\t: never\n\t\t: never\n>;\n\nexport {};\n" }, { "path": "source/exclude-strict.d.ts", "content": "/**\nA stricter version of {@link Exclude} that ensures every member of `U` can successfully exclude something from `T`.\n\nFor example, `ExcludeStrict` will error because `bigint` cannot exclude anything from `string | number | boolean`.\n\n@example\n```\n// Valid Examples\nimport type {ExcludeStrict} from 'type-fest';\n\ntype Example1 = ExcludeStrict<{status: 'success'; data: string[]} | {status: 'error'; error: string}, {status: 'success'}>;\n//=> {status: 'error'; error: string}\n\ntype Example2 = ExcludeStrict<'xs' | 's' | 'm' | 'l' | 'xl', 'xs' | 's'>;\n//=> 'm' | 'l' | 'xl'\n\ntype Example3 = ExcludeStrict<{x: number; y: number} | [number, number], unknown[]>;\n//=> {x: number; y: number}\n```\n\n@example\n```\n// Invalid Examples\nimport type {ExcludeStrict} from 'type-fest';\n\n// `'xxl'` cannot exclude anything from `'xs' | 's' | 'm' | 'l' | 'xl'`\n// @ts-expect-error\ntype Example1 = ExcludeStrict<'xs' | 's' | 'm' | 'l' | 'xl', 'xl' | 'xxl'>;\n// ~~~~~~~~~~~~\n// Error: Type \"'xl' | 'xxl'\" does not satisfy the constraint 'never'.\n\n// `unknown[]` cannot exclude anything from `{x: number; y: number} | {x: string; y: string}`\n// @ts-expect-error\ntype Example2 = ExcludeStrict<{x: number; y: number} | {x: string; y: string}, unknown[]>;\n// ~~~~~~~~~\n// Error: Type 'unknown[]' does not satisfy the constraint 'never'.\n```\n\n@category Improved Built-in\n*/\nexport type ExcludeStrict<\n\tT,\n\tU extends [U] extends [\n\t\t// Ensure every member of `U` excludes something from `T`\n\t\tU extends unknown ? ([T] extends [Exclude] ? never : U) : never,\n\t]\n\t\t? unknown\n\t\t: never,\n> = Exclude;\n\nexport {};\n" }, { "path": "source/exclusify-union.d.ts", "content": "import type {If} from './if.d.ts';\nimport type {IfNotAnyOrNever, MapsSetsOrArrays, NonRecursiveType} from './internal/type.d.ts';\nimport type {IsUnknown} from './is-unknown.d.ts';\nimport type {KeysOfUnion} from './keys-of-union.d.ts';\nimport type {Simplify} from './simplify.d.ts';\n\n/**\nEnsure mutual exclusivity in object unions by adding other members’ keys as `?: never`.\n\nUse-cases:\n- You want each union member to be exclusive, preventing overlapping object shapes.\n- You want to safely access any property defined across the union without additional type guards.\n\n@example\n```\nimport type {ExclusifyUnion} from 'type-fest';\n\ntype FileConfig = {\n\tfilePath: string;\n};\n\ntype InlineConfig = {\n\tcontent: string;\n};\n\ndeclare function loadConfig1(options: FileConfig | InlineConfig): void;\n\n// Someone could mistakenly provide both `filePath` and `content`.\nloadConfig1({filePath: './config.json', content: '{ \"name\": \"app\" }'}); // No errors\n\n// Use `ExclusifyUnion` to prevent that mistake.\ntype Config = ExclusifyUnion;\n//=> {\n// \tfilePath: string;\n// \tcontent?: never;\n// } | {\n// \tcontent: string;\n// \tfilePath?: never;\n// }\n\ndeclare function loadConfig2(options: Config): void;\n\n// @ts-expect-error\nloadConfig2({filePath: './config.json', content: '{ \"name\": \"app\" }'});\n// Error: Argument of type '{ filePath: string; content: string; }' is not assignable to parameter of type '{ filePath: string; content?: never; } | { content: string; filePath?: never; }'.\n\nloadConfig2({filePath: './config.json'}); // Ok\n\nloadConfig2({content: '{ \"name\": \"app\" }'}); // Ok\n```\n\n@example\n```\nimport type {ExclusifyUnion} from 'type-fest';\n\ntype CardPayment = {\n\tamount: number;\n\tcardNumber: string;\n};\n\ntype PaypalPayment = {\n\tamount: number;\n\tpaypalId: string;\n};\n\nfunction processPayment1(payment: CardPayment | PaypalPayment) {\n\t// @ts-expect-error\n\tconst details = payment.cardNumber ?? payment.paypalId; // Cannot access `cardNumber` or `paypalId` directly\n}\n\ntype Payment = ExclusifyUnion;\n//=> {\n// \tamount: number;\n// \tcardNumber: string;\n// \tpaypalId?: never;\n// } | {\n// \tamount: number;\n// \tpaypalId: string;\n// \tcardNumber?: never;\n// }\n\nfunction processPayment2(payment: Payment) {\n\tconst details = payment.cardNumber ?? payment.paypalId; // Ok\n\t//=> string\n}\n```\n\n@example\n```\nimport type {ExclusifyUnion} from 'type-fest';\n\ntype A = ExclusifyUnion<{a: string} | {b: number}>;\n//=> {a: string; b?: never} | {b: number; a?: never}\n\ntype B = ExclusifyUnion<{a: string} | {b: number} | {c: boolean}>;\n//=> {\n// \ta: string;\n// \tb?: never;\n// \tc?: never;\n// } | {\n// \tb: number;\n// \ta?: never;\n// \tc?: never;\n// } | {\n// \tc: boolean;\n// \ta?: never;\n// \tb?: never;\n// }\n\ntype C = ExclusifyUnion<{a: string; b: number} | {b: string; c: number}>;\n//=> {\n// \ta: string;\n// \tb: number;\n// \tc?: never;\n// } | {\n// \tb: string;\n// \tc: number;\n// \ta?: never;\n// }\n\ntype D = ExclusifyUnion<{a?: 1; readonly b: 2} | {d: 4}>;\n//=> {a?: 1; readonly b: 2; d?: never} | {d: 4; a?: never; b?: never}\n```\n\n@category Object\n@category Union\n*/\nexport type ExclusifyUnion = IfNotAnyOrNever, Union,\n\t\tExtract extends infer SkippedMembers\n\t\t\t? SkippedMembers | _ExclusifyUnion>\n\t\t\t: never\n\t>\n>;\n\ntype _ExclusifyUnion = Union extends unknown // For distributing `Union`\n\t? Simplify<\n\t\tUnion & Partial<\n\t\t\tRecord<\n\t\t\t\tExclude, keyof Union>,\n\t\t\t\tnever\n\t\t\t>\n\t\t>\n\t>\n\t: never; // Should never happen\n\nexport {};\n" }, { "path": "source/extends-strict.d.ts", "content": "import type {IsNever} from './is-never.d.ts';\nimport type {IsAny} from './is-any.d.ts';\n\n/**\nA stricter, non-distributive version of `extends` for checking whether one type is assignable to another.\n\nUnlike the built-in `extends` keyword, `ExtendsStrict`:\n\n1. Prevents distribution over union types by wrapping both types in tuples. For example, `ExtendsStrict` returns `false`, whereas `string | number extends number` would result in `boolean`.\n\n2. Treats `never` as a special case: `never` doesn't extend every other type, it only extends itself (or `any`). For example, `ExtendsStrict` returns `false` whereas `never extends number` would result in `true`.\n\n@example\n```\nimport type {ExtendsStrict} from 'type-fest';\n\ntype T1 = ExtendsStrict;\n//=> false\n\ntype T2 = ExtendsStrict;\n//=> false\n\ntype T3 = ExtendsStrict;\n//=> true\n\ntype T4 = ExtendsStrict;\n//=> true\n\ntype T5 = ExtendsStrict;\n//=> true\n```\n\n@category Improved Built-in\n*/\nexport type ExtendsStrict =\n\tIsAny extends true\n\t\t? true\n\t\t: IsNever extends true\n\t\t\t? IsNever\n\t\t\t: [Left] extends [Right]\n\t\t\t\t? true\n\t\t\t\t: false;\n\nexport {};\n" }, { "path": "source/extract-rest-element.d.ts", "content": "import type {SplitOnRestElement} from './split-on-rest-element.d.ts';\nimport type {UnknownArray} from './unknown-array.d.ts';\n\n/**\nExtract the [`rest`](https://www.typescriptlang.org/docs/handbook/2/objects.html#tuple-types) element type from an array.\n\n@example\n```\nimport type {ExtractRestElement} from 'type-fest';\n\ntype T1 = ExtractRestElement<[number, ...string[], string, 'foo']>;\n//=> string\n\ntype T2 = ExtractRestElement<[...boolean[], string]>;\n//=> boolean\n\ntype T3 = ExtractRestElement<[...Array<'foo'>, true]>;\n//=> 'foo'\n\ntype T4 = ExtractRestElement<[number, string]>;\n//=> never\n```\n\n@see {@link ExcludeRestElement}\n@see {@link SplitOnRestElement}\n@category Array\n*/\nexport type ExtractRestElement = SplitOnRestElement[1][number];\n\nexport {};\n" }, { "path": "source/extract-strict.d.ts", "content": "/**\nA stricter version of {@link Extract} that ensures every member of `U` can successfully extract something from `T`.\n\nFor example, `ExtractStrict` will error because `bigint` cannot extract anything from `string | number | boolean`.\n\n@example\n```\n// Valid Examples\nimport type {ExtractStrict} from 'type-fest';\n\ntype Example1 = ExtractStrict<{status: 'success'; data: string[]} | {status: 'error'; error: string}, {status: 'success'}>;\n//=> {status: 'success'; data: string[]}\n\ntype Example2 = ExtractStrict<'xs' | 's' | 'm' | 'l' | 'xl', 'xs' | 's'>;\n//=> 'xs' | 's'\n\ntype Example3 = ExtractStrict<{x: number; y: number} | [number, number], unknown[]>;\n//=> [number, number]\n```\n\n@example\n```\n// Invalid Examples\nimport type {ExtractStrict} from 'type-fest';\n\n// `'xxl'` cannot extract anything from `'xs' | 's' | 'm' | 'l' | 'xl'`\n// @ts-expect-error\ntype Example1 = ExtractStrict<'xs' | 's' | 'm' | 'l' | 'xl', 'xl' | 'xxl'>;\n// ~~~~~~~~~~~~\n// Error: Type \"'xl' | 'xxl'\" does not satisfy the constraint 'never'.\n\n// `unknown[]` cannot extract anything from `{x: number; y: number} | {x: string; y: string}`\n// @ts-expect-error\ntype Example2 = ExtractStrict<{x: number; y: number} | {x: string; y: string}, unknown[]>;\n// ~~~~~~~~~\n// Error: Type 'unknown[]' does not satisfy the constraint 'never'.\n```\n\n@category Improved Built-in\n*/\nexport type ExtractStrict<\n\tT,\n\tU extends [U] extends [\n\t\t// Ensure every member of `U` extracts something from `T`\n\t\tU extends unknown ? (Extract extends never ? never : U) : never,\n\t]\n\t\t? unknown\n\t\t: never,\n> = Extract;\n\nexport {};\n" }, { "path": "source/find-global-type.d.ts", "content": "/**\nTries to find the type of a global with the given name.\n\nLimitations: Due to peculiarities with the behavior of `globalThis`, \"globally defined\" only includes `var` declarations in `declare global` blocks, not `let` or `const` declarations.\n\n@example\n```\nimport type {FindGlobalType} from 'type-fest';\n\ndeclare global {\n\tconst foo: number; // let and const don't work\n\tvar bar: string; // var works\n}\n\ntype FooType = FindGlobalType<'foo'>; //=> never (let/const don't work)\ntype BarType = FindGlobalType<'bar'>; //=> string\ntype OtherType = FindGlobalType<'other'>; //=> never (no global named 'other')\n```\n\n@category Utilities\n*/\nexport type FindGlobalType = typeof globalThis extends Record ? T : never;\n\n/**\nTries to find one or more types from their globally-defined constructors.\n\nUse-case: Conditionally referencing DOM types only when the DOM library present.\n\n*Limitations:* Due to peculiarities with the behavior of `globalThis`, \"globally defined\" has a narrow definition in this case. Declaring a class in a `declare global` block won't work, instead you must declare its type using an interface and declare its constructor as a `var` (*not* `let`/`const`) inside the `declare global` block.\n\n@example\n```\nimport type {FindGlobalInstanceType} from 'type-fest';\n\nclass Point {\n\tconstructor(public x: number, public y: number) {}\n}\n\ntype PointLike = Point | FindGlobalInstanceType<'DOMPoint'>;\n```\n\n@example\n```\nimport type {FindGlobalInstanceType} from 'type-fest';\n\ndeclare global {\n\t// Class syntax won't add the key to `globalThis`\n\tclass Foo {}\n\n\t// interface + constructor style works\n\tinterface Bar {\n\t\tbar: string;\n\t}\n\tvar Bar: new () => Bar; // Not let or const\n}\n\ntype FindFoo = FindGlobalInstanceType<'Foo'>; // Doesn't work\ntype FindBar = FindGlobalInstanceType<'Bar'>; // Works\n```\n\n@category Utilities\n*/\nexport type FindGlobalInstanceType =\n\tName extends string\n\t\t? typeof globalThis extends Record infer T> ? T : never\n\t\t: never;\n\nexport {};\n" }, { "path": "source/fixed-length-array.d.ts", "content": "import type {Except} from './except.d.ts';\nimport type {TupleOf} from './tuple-of.d.ts';\n\n/**\nMethods to exclude.\n*/\ntype ArrayLengthMutationKeys = 'splice' | 'push' | 'pop' | 'shift' | 'unshift';\n\n/**\nCreate a type that represents an array of the given type and length. The `Array` prototype methods that manipulate its length are excluded from the resulting type.\n\nThe problem with the built-in tuple type is that it allows mutating methods like `push`, `pop` etc, which can cause issues, like in the following example:\n\n@example\n```\nconst color: [number, number, number] = [255, 128, 64];\n\nfunction toHex([r, g, b]: readonly [number, number, number]) {\n\treturn `#${r.toString(16)}${g.toString(16)}${b.toString(16)}`;\n}\n\ncolor.pop(); // Allowed\n\nconsole.log(toHex(color)); // Compiles fine, but fails at runtime since index `2` no longer contains a `number`.\n```\n\n`ArrayLengthMutationKeys` solves this problem by excluding methods like `push`, `pop` etc from the resulting type.\n\n@example\n```\nimport type {FixedLengthArray} from 'type-fest';\n\nconst color: FixedLengthArray = [255, 128, 64];\n\n// @ts-expect-error\ncolor.pop();\n// Error: Property 'pop' does not exist on type 'FixedLengthArray'.\n```\n\nUse-cases:\n- Declaring fixed-length tuples or arrays with a large number of items.\n- Creating an array of coordinates with a static length, for example, length of 3 for a 3D vector.\n\n@example\n```\nimport type {FixedLengthArray} from 'type-fest';\n\nlet color: FixedLengthArray = [255, 128, 64];\n\nconst red = color[0];\n//=> number\nconst green = color[1];\n//=> number\nconst blue = color[2];\n//=> number\n\n// @ts-expect-error\nconst alpha = color[3];\n// Error: Property '3' does not exist on type 'FixedLengthArray'.\n\n// You can write to valid indices.\ncolor[0] = 128;\ncolor[1] = 64;\ncolor[2] = 32;\n\n// But you cannot write to out-of-bounds indices.\n// @ts-expect-error\ncolor[3] = 0.5;\n// Error: Property '3' does not exist on type 'FixedLengthArray'.\n\n// @ts-expect-error\ncolor.push(0.5);\n// Error: Property 'push' does not exist on type 'FixedLengthArray'.\n\n// @ts-expect-error\ncolor = [0, 128, 255, 0.5];\n// Error: Type '[number, number, number, number]' is not assignable to type 'FixedLengthArray'. Types of property 'length' are incompatible.\n\n// @ts-expect-error\ncolor.length = 4;\n// Error: Cannot assign to 'length' because it is a read-only property.\n\nfunction toHex([r, g, b]: readonly [number, number, number]) {\n\treturn `#${r.toString(16)}${g.toString(16)}${b.toString(16)}`;\n}\n\nconsole.log(toHex(color)); // `FixedLengthArray` is assignable to `readonly [number, number, number]`.\n```\n\n@category Array\n*/\nexport type FixedLengthArray =\n\tExcept, ArrayLengthMutationKeys | number | 'length'>\n\t& {readonly length: Length}\n\t& (number extends Length ? {[n: number]: Element} : {}); // Add `number` index signature only for non-tuple arrays.\n\nexport {};\n" }, { "path": "source/get.d.ts", "content": "import type {ApplyDefaultOptions, ToString} from './internal/index.d.ts';\nimport type {_LiteralStringUnion} from './literal-union.d.ts';\nimport type {Paths} from './paths.d.ts';\nimport type {Split} from './split.d.ts';\nimport type {KeyAsString} from './key-as-string.d.ts';\nimport type {DigitCharacter} from './characters.d.ts';\n\nexport type GetOptions = {\n\t/**\n\tInclude `undefined` in the return type when accessing properties.\n\n\tSetting this to `false` is not recommended.\n\n\t@default true\n\t*/\n\tstrict?: boolean;\n};\n\ntype DefaultGetOptions = {\n\tstrict: true;\n};\n\n/**\nLike the `Get` type but receives an array of strings as a path parameter.\n*/\ntype GetWithPath> =\n\tKeys extends readonly []\n\t\t? BaseType\n\t\t: Keys extends readonly [infer Head, ...infer Tail]\n\t\t\t? GetWithPath<\n\t\t\t\tPropertyOf, Options>,\n\t\t\t\tExtract,\n\t\t\t\tOptions\n\t\t\t>\n\t\t\t: never;\n\n/**\nAdds `undefined` to `Type` if `strict` is enabled.\n*/\ntype Strictify> =\n\tOptions['strict'] extends false ? Type : (Type | undefined);\n\n/**\nIf `Options['strict']` is `true`, includes `undefined` in the returned type when accessing properties on `Record`.\n\nKnown limitations:\n- Does not include `undefined` in the type on object types with an index signature (for example, `{a: string; [key: string]: string}`).\n*/\ntype StrictPropertyOf> =\n\tRecord extends BaseType\n\t\t? string extends keyof BaseType\n\t\t\t? Strictify // Record\n\t\t\t: BaseType[Key] // Record<'a' | 'b', any> (Records with a string union as keys have required properties)\n\t\t: BaseType[Key];\n\n/**\nSplits a dot-prop style path into a tuple comprised of the properties in the path. Handles square-bracket notation.\n\n@example\n```\ntype A = ToPath<'foo.bar.baz'>;\n//=> ['foo', 'bar', 'baz']\n\ntype B = ToPath<'foo[0].bar.baz'>;\n//=> ['foo', '0', 'bar', 'baz']\n```\n*/\ntype ToPath = Split, '.', {strictLiteralChecks: false}>;\n\n/**\nReplaces square-bracketed dot notation with dots, for example, `foo[0].bar` -> `foo.0.bar`.\n*/\ntype FixPathSquareBrackets =\n\tPath extends `[${infer Head}]${infer Tail}`\n\t\t? Tail extends `[${string}`\n\t\t\t? `${Head}.${FixPathSquareBrackets}`\n\t\t\t: `${Head}${FixPathSquareBrackets}`\n\t\t: Path extends `${infer Head}[${infer Middle}]${infer Tail}`\n\t\t\t? `${Head}.${FixPathSquareBrackets<`[${Middle}]${Tail}`>}`\n\t\t\t: Path;\n\n/**\nReturns true if `LongString` is made up out of `Substring` repeated 0 or more times.\n\n@example\n```\ntype A = ConsistsOnlyOf<'aaa', 'a'>; //=> true\ntype B = ConsistsOnlyOf<'ababab', 'ab'>; //=> true\ntype C = ConsistsOnlyOf<'aBa', 'a'>; //=> false\ntype D = ConsistsOnlyOf<'', 'a'>; //=> true\n```\n*/\ntype ConsistsOnlyOf =\n\tLongString extends ''\n\t\t? true\n\t\t: LongString extends `${Substring}${infer Tail}`\n\t\t\t? ConsistsOnlyOf\n\t\t\t: false;\n\n/**\nConvert a type which may have number keys to one with string keys, making it possible to index using strings retrieved from template types.\n\n@example\n```\ntype WithNumbers = {foo: string; 0: boolean};\ntype WithStrings = WithStringKeys;\n\ntype WithNumbersKeys = keyof WithNumbers;\n//=> 'foo' | 0\ntype WithStringsKeys = keyof WithStrings;\n//=> 'foo' | '0'\n```\n*/\ntype WithStringKeys = {\n\t[Key in KeyAsString]: UncheckedIndex\n};\n\n/**\nPerform a `T[U]` operation if `T` supports indexing.\n*/\ntype UncheckedIndex = [T] extends [Record] ? T[U] : never;\n\n/**\nGet a property of an object or array. Works when indexing arrays using number-literal-strings, for example, `PropertyOf = number`, and when indexing objects with number keys.\n\nNote:\n- Returns `unknown` if `Key` is not a property of `BaseType`, since TypeScript uses structural typing, and it cannot be guaranteed that extra properties unknown to the type system will exist at runtime.\n- Returns `undefined` from nullish values, to match the behaviour of most deep-key libraries like `lodash`, `dot-prop`, etc.\n*/\ntype PropertyOf> =\n\tBaseType extends null | undefined\n\t\t? undefined\n\t\t: Key extends keyof BaseType\n\t\t\t? StrictPropertyOf\n\t\t\t// Handle arrays and tuples\n\t\t\t: BaseType extends readonly unknown[]\n\t\t\t\t? Key extends `${number}`\n\t\t\t\t\t// For arrays with unknown length (regular arrays)\n\t\t\t\t\t? number extends BaseType['length']\n\t\t\t\t\t\t? Strictify\n\t\t\t\t\t\t// For tuples: check if the index is valid\n\t\t\t\t\t\t: Key extends keyof BaseType\n\t\t\t\t\t\t\t? Strictify\n\t\t\t\t\t\t\t// Out-of-bounds access for tuples\n\t\t\t\t\t\t\t: unknown\n\t\t\t\t\t// Non-numeric string key for arrays/tuples\n\t\t\t\t\t: unknown\n\t\t\t\t// Handle array-like objects\n\t\t\t\t: BaseType extends {\n\t\t\t\t\t[n: number]: infer Item;\n\t\t\t\t\tlength: number; // Note: This is needed to avoid being too lax with records types using number keys like `{0: string; 1: boolean}`.\n\t\t\t\t}\n\t\t\t\t\t? (\n\t\t\t\t\t\tConsistsOnlyOf extends true\n\t\t\t\t\t\t\t? Strictify\n\t\t\t\t\t\t\t: unknown\n\t\t\t\t\t)\n\t\t\t\t\t: Key extends keyof WithStringKeys\n\t\t\t\t\t\t? StrictPropertyOf, Key, Options>\n\t\t\t\t\t\t: unknown;\n\n// This works by first splitting the path based on `.` and `[...]` characters into a tuple of string keys. Then it recursively uses the head key to get the next property of the current object, until there are no keys left. Number keys extract the item type from arrays, or are converted to strings to extract types from tuples and dictionaries with number keys.\n/**\nGet a deeply-nested property from an object using a key path, like Lodash's `.get()` function.\n\nUse-case: Retrieve a property from deep inside an API response or some other complex object.\n\n@example\n```\nimport type {Get} from 'type-fest';\n\ndeclare function get(object: BaseType, path: Path): Get;\n\ntype ApiResponse = {\n\thits: {\n\t\thits: Array<{\n\t\t\t_id: string;\n\t\t\t_source: {\n\t\t\t\tname: Array<{\n\t\t\t\t\tgiven: string[];\n\t\t\t\t\tfamily: string;\n\t\t\t\t}>;\n\t\t\t\tbirthDate: string;\n\t\t\t};\n\t\t}>;\n\t};\n};\n\nconst getName = (apiResponse: ApiResponse) => get(apiResponse, 'hits.hits[0]._source.name');\n//=> (apiResponse: ApiResponse) => {\n// \tgiven: string[];\n// \tfamily: string;\n// }[] | undefined\n\n// Path also supports a readonly array of strings\nconst getNameWithPathArray = (apiResponse: ApiResponse) => get(apiResponse, ['hits', 'hits', '0', '_source', 'name']);\n//=> (apiResponse: ApiResponse) => {\n// \tgiven: string[];\n// \tfamily: string;\n// }[] | undefined\n\n// Non-strict mode:\ntype A = Get;\n//=> string\n\ntype B = Get, 'foo', {strict: true}>;\n//=> string | undefined\n```\n\n@category Object\n@category Array\n@category Template literal\n*/\nexport type Get<\n\tBaseType,\n\tPath extends\n\t| readonly string[]\n\t| _LiteralStringUnion | Paths>>,\n\tOptions extends GetOptions = {},\n> =\n\tGetWithPath<\n\t\tBaseType,\n\t\tPath extends string ? ToPath : Path,\n\t\tApplyDefaultOptions\n\t>;\n\nexport {};\n" }, { "path": "source/global-this.d.ts", "content": "/**\nDeclare locally scoped properties on `globalThis`.\n\nWhen defining a global variable in a declaration file is inappropriate, it can be helpful to define a `type` or `interface` (say `ExtraGlobals`) with the global variable and then cast `globalThis` via code like `globalThis as unknown as ExtraGlobals`.\n\nInstead of casting through `unknown`, you can update your `type` or `interface` to extend `GlobalThis` and then directly cast `globalThis`.\n\n@example\n```\nimport type {GlobalThis} from 'type-fest';\n\ntype ExtraGlobals = GlobalThis & {\n\treadonly GLOBAL_TOKEN: string;\n};\n\nconst globalToken = (globalThis as ExtraGlobals).GLOBAL_TOKEN;\n//=> string\n```\n\n@category Type\n*/\nexport type GlobalThis = typeof globalThis;\n\nexport {};\n" }, { "path": "source/globals/index.d.ts", "content": "export type * from './observable-like.d.ts';\n\nexport {};\n" }, { "path": "source/globals/observable-like.d.ts", "content": "declare global {\n\t// eslint-disable-next-line @typescript-eslint/consistent-type-definitions -- It has to be an `interface` so that it can be merged.\n\tinterface SymbolConstructor {\n\t\treadonly observable: symbol;\n\t}\n}\n\n/**\n@remarks\nThe TC39 observable proposal defines a `closed` property, but some implementations (such as xstream) do not as of 10/08/2021.\nAs well, some guidance on making an `Observable` to not include `closed` property.\n\n@see https://github.com/tc39/proposal-observable/blob/master/src/Observable.js#L129-L130\n@see https://github.com/staltz/xstream/blob/6c22580c1d84d69773ee4b0905df44ad464955b3/src/index.ts#L79-L85\n@see https://github.com/benlesh/symbol-observable#making-an-object-observable\n\n@category Observable\n*/\n// eslint-disable-next-line type-fest/require-exported-types\nexport type Unsubscribable = {\n\tunsubscribe(): void;\n};\n\n/**\n@category Observable\n*/\ntype OnNext = (value: ValueType) => void;\n\n/**\n@category Observable\n*/\ntype OnError = (error: unknown) => void;\n\n/**\n@category Observable\n*/\ntype OnComplete = () => void;\n\n/**\n@category Observable\n*/\n// eslint-disable-next-line type-fest/require-exported-types\nexport type Observer = {\n\tnext: OnNext;\n\terror: OnError;\n\tcomplete: OnComplete;\n};\n\n/**\nMatches a value that is like an [Observable](https://github.com/tc39/proposal-observable).\n\nYou must import it as a sub-import:\n\n@example\n```\nimport type {ObservableLike} from 'type-fest/globals';\n```\n\n@remarks\nThe TC39 Observable proposal defines 2 forms of `subscribe()`:\n1. Three callback arguments: `subscribe(observer: OnNext, onError?: OnError, onComplete?: OnComplete): Unsubscribable;`\n2. A single `observer` argument: (as defined below)\n\nBut `Observable` implementations have evolved to preferring case 2 and some implementations choose not to implement case 1. Therefore, an `ObservableLike` cannot be trusted to implement the first case. (xstream and hand built observerables often do not implement case 1)\n\n@see https://github.com/tc39/proposal-observable#observable\n@see https://github.com/tc39/proposal-observable/blob/master/src/Observable.js#L246-L259\n@see https://benlesh.com/posts/learning-observable-by-building-observable/\n\n@category Observable\n*/\n// eslint-disable-next-line type-fest/require-exported-types\nexport type ObservableLike = {\n\tsubscribe(observer?: Partial>): Unsubscribable;\n\t[Symbol.observable](): ObservableLike;\n};\n\nexport {};\n" }, { "path": "source/greater-than-or-equal.d.ts", "content": "import type {GreaterThan} from './greater-than.d.ts';\n\n/**\nReturns a boolean for whether a given number is greater than or equal to another number.\n\n@example\n```\nimport type {GreaterThanOrEqual} from 'type-fest';\n\ntype A = GreaterThanOrEqual<1, -5>;\n//=> true\n\ntype B = GreaterThanOrEqual<1, 1>;\n//=> true\n\ntype C = GreaterThanOrEqual<1, 5>;\n//=> false\n```\n\nNote: If either argument is the non-literal `number` type, the result is `boolean`.\n\n@example\n```\nimport type {GreaterThanOrEqual} from 'type-fest';\n\ntype A = GreaterThanOrEqual;\n//=> boolean\n\ntype B = GreaterThanOrEqual<1, number>;\n//=> boolean\n\ntype C = GreaterThanOrEqual;\n//=> boolean\n```\n\n@example\n```\nimport type {GreaterThanOrEqual} from 'type-fest';\n\n// Use `GreaterThanOrEqual` to constrain a function parameter to non-negative numbers.\ndeclare function setNonNegative(value: GreaterThanOrEqual extends true ? N : never): void;\n\nsetNonNegative(0); // ✅ Allowed\nsetNonNegative(1); // ✅ Allowed\n\n// @ts-expect-error\nsetNonNegative(-1);\n\n// @ts-expect-error\nsetNonNegative(-2);\n```\n*/\nexport type GreaterThanOrEqual = number extends A | B\n\t? boolean\n\t: A extends number // For distributing `A`\n\t\t? B extends number // For distributing `B`\n\t\t\t? A extends B\n\t\t\t\t? true\n\t\t\t\t: GreaterThan\n\t\t\t: never // Should never happen\n\t\t: never; // Should never happen\n\nexport {};\n" }, { "path": "source/greater-than.d.ts", "content": "import type {NumberAbsolute, PositiveNumericStringGt} from './internal/index.d.ts';\nimport type {IsEqual} from './is-equal.d.ts';\nimport type {PositiveInfinity, NegativeInfinity, IsNegative} from './numeric.d.ts';\nimport type {And} from './and.d.ts';\nimport type {Or} from './or.d.ts';\n\n/**\nReturns a boolean for whether a given number is greater than another number.\n\n@example\n```\nimport type {GreaterThan} from 'type-fest';\n\ntype A = GreaterThan<1, -5>;\n//=> true\n\ntype B = GreaterThan<1, 1>;\n//=> false\n\ntype C = GreaterThan<1, 5>;\n//=> false\n```\n\nNote: If either argument is the non-literal `number` type, the result is `boolean`.\n\n@example\n```\nimport type {GreaterThan} from 'type-fest';\n\ntype A = GreaterThan;\n//=> boolean\n\ntype B = GreaterThan<1, number>;\n//=> boolean\n\ntype C = GreaterThan;\n//=> boolean\n```\n\n@example\n```\nimport type {GreaterThan} from 'type-fest';\n\n// Use `GreaterThan` to constrain a function parameter to positive numbers.\ndeclare function setPositive(value: GreaterThan extends true ? N : never): void;\n\nsetPositive(1); // ✅ Allowed\nsetPositive(2); // ✅ Allowed\n\n// @ts-expect-error\nsetPositive(0);\n\n// @ts-expect-error\nsetPositive(-1);\n```\n*/\nexport type GreaterThan =\n\tA extends number // For distributing `A`\n\t\t? B extends number // For distributing `B`\n\t\t\t? number extends A | B\n\t\t\t\t? boolean\n\t\t\t\t: [\n\t\t\t\t\tIsEqual, IsEqual,\n\t\t\t\t\tIsEqual, IsEqual,\n\t\t\t\t] extends infer R extends [boolean, boolean, boolean, boolean]\n\t\t\t\t\t? Or<\n\t\t\t\t\t\tAnd, IsEqual>,\n\t\t\t\t\t\tAnd, IsEqual>\n\t\t\t\t\t> extends true\n\t\t\t\t\t\t? true\n\t\t\t\t\t\t: Or<\n\t\t\t\t\t\t\tAnd, IsEqual>,\n\t\t\t\t\t\t\tAnd, IsEqual>\n\t\t\t\t\t\t> extends true\n\t\t\t\t\t\t\t? false\n\t\t\t\t\t\t\t: true extends R[number]\n\t\t\t\t\t\t\t\t? false\n\t\t\t\t\t\t\t\t: [IsNegative, IsNegative] extends infer R extends [boolean, boolean]\n\t\t\t\t\t\t\t\t\t? [true, false] extends R\n\t\t\t\t\t\t\t\t\t\t? false\n\t\t\t\t\t\t\t\t\t\t: [false, true] extends R\n\t\t\t\t\t\t\t\t\t\t\t? true\n\t\t\t\t\t\t\t\t\t\t\t: [false, false] extends R\n\t\t\t\t\t\t\t\t\t\t\t\t? PositiveNumericStringGt<`${A}`, `${B}`>\n\t\t\t\t\t\t\t\t\t\t\t\t: PositiveNumericStringGt<`${NumberAbsolute}`, `${NumberAbsolute}`>\n\t\t\t\t\t\t\t\t\t: never\n\t\t\t\t\t: never\n\t\t\t: never // Should never happen\n\t\t: never; // Should never happen\n\nexport {};\n" }, { "path": "source/has-optional-keys.d.ts", "content": "import type {OptionalKeysOf} from './optional-keys-of.d.ts';\n\n/**\nCreates a type that represents `true` or `false` depending on whether the given type has any optional fields.\n\nThis is useful when you want to create an API whose behavior depends on the presence or absence of optional fields.\n\n@example\n```\nimport type {HasOptionalKeys, OptionalKeysOf} from 'type-fest';\n\ntype UpdateService = {\n\tremoveField: HasOptionalKeys extends true\n\t\t? (field: OptionalKeysOf) => Promise\n\t\t: never;\n};\n```\n\n@category Utilities\n*/\nexport type HasOptionalKeys = OptionalKeysOf extends never ? false : true;\n\nexport {};\n" }, { "path": "source/has-readonly-keys.d.ts", "content": "import type {ReadonlyKeysOf} from './readonly-keys-of.d.ts';\n\n/**\nCreates a type that represents `true` or `false` depending on whether the given type has any readonly fields.\n\nThis is useful when you want to create an API whose behavior depends on the presence or absence of readonly fields.\n\n@example\n```\nimport type {HasReadonlyKeys, ReadonlyKeysOf} from 'type-fest';\n\ntype UpdateService = {\n\tremoveField: HasReadonlyKeys extends true\n\t\t? (field: ReadonlyKeysOf) => Promise\n\t\t: never;\n};\n```\n\n@category Utilities\n*/\nexport type HasReadonlyKeys = ReadonlyKeysOf extends never ? false : true;\n\nexport {};\n" }, { "path": "source/has-required-keys.d.ts", "content": "import type {RequiredKeysOf} from './required-keys-of.d.ts';\n\n/**\nCreates a type that represents `true` or `false` depending on whether the given type has any required fields.\n\nThis is useful when you want to create an API whose behavior depends on the presence or absence of required fields.\n\n@example\n```\nimport type {HasRequiredKeys} from 'type-fest';\n\ntype GeneratorOptions