[ { "path": ".editorconfig", "content": "[*]\nindent_style = tab\nindent_size = 2\n\n[*.{js,json,ts}]\nindent_style = space\nindent_size = 2\n" }, { "path": ".github/ISSUE_TEMPLATE/new-issue.md", "content": "---\nname: New issue\nabout: This is the template for new issues.\ntitle: ''\nlabels: ''\nassignees: ''\n\n---\n\n\n" }, { "path": ".github/workflows/ci.yml", "content": "name: CI\n\non:\n push:\n branches: ['*']\n pull_request:\n branches: ['*']\n workflow_dispatch:\n\npermissions:\n contents: read # to fetch code (actions/checkout)\n\njobs:\n esbuild-platforms:\n # Split this out into its own runner because it's slow\n name: esbuild CI (All Platforms)\n runs-on: ubuntu-latest\n\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Read go.version\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $GITHUB_ENV\n\n - name: Set up Go 1.x\n uses: actions/setup-go@v3\n with:\n go-version: ${{ env.GO_VERSION }}\n id: go\n\n - name: Setup Node.js environment\n uses: actions/setup-node@v3\n with:\n node-version: 18\n\n - name: Ensure all platforms can be built\n run: make platform-all\n\n # Plan 9 is not a supported platform, but someone wanted esbuild to be able to build for it anyway...\n - name: Ensure esbuild can be built for Plan 9\n run: |\n GOOS=plan9 GOARCH=386 go build ./cmd/esbuild\n GOOS=plan9 GOARCH=amd64 go build ./cmd/esbuild\n GOOS=plan9 GOARCH=arm go build ./cmd/esbuild\n\n esbuild-slow:\n # Split these out into their own runner because they're very slow\n name: esbuild CI (Slow Tests)\n runs-on: ubuntu-latest\n\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Read go.version\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $GITHUB_ENV\n\n - name: Set up Go 1.x\n uses: actions/setup-go@v3\n with:\n go-version: ${{ env.GO_VERSION }}\n id: go\n\n - name: Setup Node.js environment\n uses: actions/setup-node@v3\n with:\n node-version: 16\n\n # Note: These tests break with node version 18. Something about WebAssembly.\n - name: Rollup Tests\n run: make test-rollup\n\n - name: Uglify Tests\n run: CI=1 make uglify\n\n - name: Type check tsc using tsc\n run: make test-tsc\n\n esbuild:\n name: esbuild CI\n runs-on: ${{ matrix.os }}\n strategy:\n matrix:\n os: [ubuntu-latest, macos-latest, windows-latest]\n\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Read go.version (non-Windows)\n if: matrix.os != 'windows-latest'\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $GITHUB_ENV\n\n - name: Read go.version (Windows)\n if: matrix.os == 'windows-latest'\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $Env:GITHUB_ENV\n\n - name: Set up Go 1.x\n uses: actions/setup-go@v3\n with:\n go-version: ${{ env.GO_VERSION }}\n id: go\n\n - name: Setup Node.js environment\n uses: actions/setup-node@v3\n with:\n node-version: 18\n\n - name: Setup Deno 1.40.0\n uses: denoland/setup-deno@main\n with:\n deno-version: v1.40.0\n\n - name: go test\n run: go test -race ./internal/...\n\n - name: go vet\n run: go vet ./cmd/... ./internal/... ./pkg/...\n\n - name: Deno Tests (non-Windows)\n if: matrix.os != 'windows-latest'\n run: make test-deno\n\n - name: Deno Tests (Windows)\n if: matrix.os == 'windows-latest'\n run: make test-deno-windows\n\n - name: Test for path/filepath\n if: matrix.os == 'ubuntu-latest'\n run: make no-filepath\n\n - name: Make sure \"check-go-version\" works (non-Windows)\n if: matrix.os != 'windows-latest'\n run: make check-go-version\n\n - name: go fmt\n if: matrix.os == 'macos-latest'\n run: make fmt-go\n\n - name: npm ci\n run: cd scripts && npm ci\n\n - name: Register Test (ESBUILD_WORKER_THREADS=0, non-Windows)\n if: matrix.os != 'windows-latest'\n run: ESBUILD_WORKER_THREADS=0 node scripts/register-test.js\n\n - name: Register Test\n run: node scripts/register-test.js\n\n - name: Verify Source Map\n run: node scripts/verify-source-map.js\n\n - name: E2E Tests\n run: node scripts/end-to-end-tests.js\n\n - name: JS API Tests (ESBUILD_WORKER_THREADS=0, non-Windows)\n if: matrix.os != 'windows-latest'\n run: ESBUILD_WORKER_THREADS=0 node scripts/js-api-tests.js\n\n - name: JS API Tests\n run: node scripts/js-api-tests.js\n\n - name: NodeJS Unref Tests\n run: node scripts/node-unref-tests.js\n\n - name: Plugin Tests\n run: node scripts/plugin-tests.js\n\n - name: TypeScript Type Definition Tests\n if: matrix.os == 'ubuntu-latest'\n run: node scripts/ts-type-tests.js\n\n - name: JS API Type Check\n if: matrix.os == 'ubuntu-latest'\n run: make lib-typecheck\n\n - name: Decorator Tests\n if: matrix.os == 'ubuntu-latest'\n run: make decorator-tests\n\n - name: WebAssembly API Tests (browser)\n if: matrix.os == 'ubuntu-latest'\n run: make test-wasm-browser\n\n - name: WebAssembly API Tests (node, Linux)\n if: matrix.os == 'ubuntu-latest'\n run: make test-wasm-node\n\n - name: WebAssembly API Tests (node, non-Linux)\n if: matrix.os != 'ubuntu-latest'\n run: node scripts/wasm-tests.js\n\n - name: Sucrase Tests\n if: matrix.os == 'ubuntu-latest'\n run: make test-sucrase\n\n - name: Esprima Tests\n if: matrix.os == 'ubuntu-latest'\n run: make test-esprima\n\n - name: Preact Splitting Tests\n if: matrix.os == 'ubuntu-latest'\n run: make test-preact-splitting\n\n - name: Check the unicode table generator\n if: matrix.os == 'ubuntu-latest'\n run: cd scripts && node gen-unicode-table.js\n\n - name: Yarn PnP tests\n run: |\n # Note that Yarn recently deliberately broke \"npm install -g yarn\".\n # They say you now have to run \"corepack enable\" to fix it. They have\n # written about this here: https://yarnpkg.com/corepack\n corepack enable\n\n make test-yarnpnp\n\n esbuild-old-go-version:\n name: esbuild CI (old Go version)\n runs-on: ubuntu-latest\n\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Set up Go 1.13 (the minimum required Go version for esbuild)\n uses: actions/setup-go@v3\n with:\n go-version: 1.13\n id: go\n\n - name: go build\n run: go build ./cmd/esbuild\n\n - name: go test\n run: go test ./internal/...\n\n - name: make test-old-ts\n run: make test-old-ts\n\n esbuild-old-deno-version:\n name: esbuild CI (old Deno version)\n runs-on: ${{ matrix.os }}\n strategy:\n matrix:\n # Note: I'm excluding \"macos-latest\" here because GitHub recently\n # changed their macOS CI VMs from x86_64 to aarch64 (i.e. from Intel\n # to ARM) and it looks like old Deno versions have WASM bugs on ARM.\n # Specifically, this test now crashes like this when run on macOS:\n #\n # #\n # # Fatal error in , line 0\n # # Check failed: RwxMemoryWriteScope::IsAllowed().\n # #\n # #\n # #\n # #FailureMessage Object: 0x16f282368\n # ==== C stack trace ===============================\n #\n # 0 deno 0x0000000101bb8e78 v8::base::debug::StackTrace::StackTrace() + 24\n # 1 deno 0x0000000101bbda84 v8::platform::(anonymous namespace)::PrintStackTrace() + 24\n # 2 deno 0x0000000101bb6230 V8_Fatal(char const*, ...) + 268\n # 3 deno 0x000000010227e468 v8::internal::wasm::WasmCodeManager::MemoryProtectionKeysEnabled() const + 0\n # 4 deno 0x0000000102299994 v8::internal::wasm::WasmEngine::InitializeOncePerProcess() + 44\n # 5 deno 0x0000000101e78fd0 v8::internal::V8::Initialize() + 1576\n # 6 deno 0x0000000101c3b7d8 v8::V8::Initialize(int) + 32\n # 7 deno 0x00000001011833dc _ZN3std4sync4once4Once9call_once28_$u7b$$u7b$closure$u7d$$u7d$17h2bbe74d315ab3e84E + 488\n # 8 deno 0x00000001017f8854 std::sync::once::Once::call_inner::h70fbdd48fe002a01 + 724\n # 9 deno 0x000000010115ca80 deno_core::runtime::JsRuntime::new::h9c5f1a9c910f1eed + 192\n # 10 deno 0x00000001014d3b50 deno_runtime::worker::MainWorker::bootstrap_from_options::h91a0eaac48dfc18e + 4260\n # 11 deno 0x0000000100ee692c deno::create_main_worker::h0d1622755821ae7f + 1608\n # 12 deno 0x0000000100f6c688 _ZN97_$LT$core..future..from_generator..GenFuture$LT$T$GT$$u20$as$u20$core..future..future..Future$GT$4poll17h87ddfac9566887c8E + 492\n # 13 deno 0x0000000100f6ba18 tokio::runtime::task::raw::poll::h7d51f1a7d5a61c15 + 1396\n # 14 deno 0x0000000101917b98 std::sys_common::backtrace::__rust_begin_short_backtrace::hd384935dcffe6f2d + 332\n # 15 deno 0x0000000101917954 _ZN4core3ops8function6FnOnce40call_once$u7b$$u7b$vtable.shim$u7d$$u7d$17he2755732d5d29cf0E + 124\n # 16 deno 0x0000000101829684 std::sys::unix::thread::Thread::new::thread_start::h432bc30153e41f60 + 48\n # 17 libsystem_pthread.dylib 0x000000018a436f94 _pthread_start + 136\n # 18 libsystem_pthread.dylib 0x000000018a431d34 thread_start + 8\n #\n # Hopefully running this old Deno version on Linux is sufficiently\n # close to running it on macOS. For reference, I believe this is the\n # change that GitHub made which broke this test:\n # https://github.blog/changelog/2023-10-02-github-actions-apple-silicon-m1-macos-runners-are-now-available-in-public-beta/\n os: [ubuntu-latest, windows-latest]\n\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Read go.version (non-Windows)\n if: matrix.os != 'windows-latest'\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $GITHUB_ENV\n\n - name: Read go.version (Windows)\n if: matrix.os == 'windows-latest'\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $Env:GITHUB_ENV\n\n - name: Set up Go 1.x\n uses: actions/setup-go@v3\n with:\n go-version: ${{ env.GO_VERSION }}\n id: go\n\n # Make sure esbuild works with old versions of Deno. Note: It's important\n # to test a version before 1.31.0, which introduced the \"Deno.Command\" API.\n - name: Setup Deno 1.24.0\n uses: denoland/setup-deno@main\n with:\n deno-version: v1.24.0\n\n - name: Setup Node.js environment\n uses: actions/setup-node@v3\n with:\n node-version: 18\n\n - name: Deno Tests (non-Windows)\n if: matrix.os != 'windows-latest'\n run: make test-deno\n\n - name: Deno Tests (Windows)\n if: matrix.os == 'windows-latest'\n run: make test-deno-windows\n" }, { "path": ".github/workflows/e2e.yml", "content": "name: End-to-end install tests\n\non:\n schedule:\n - cron: '0 */6 * * *'\n workflow_dispatch:\n\npermissions:\n contents: read # to fetch code (actions/checkout)\n\njobs:\n validate:\n runs-on: ubuntu-latest\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Setup Node.js environment\n uses: actions/setup-node@v3\n with:\n node-version: 18\n\n # The version of Deno is pinned because version 1.25.1 was causing test\n # flakes due to random segfaults.\n - name: Setup Deno 1.24.0\n uses: denoland/setup-deno@main\n with:\n deno-version: v1.24.0\n\n - name: Test npm\n run: |\n npm i -g npm@next-7\n time make test-e2e-npm\n\n - name: Test pnpm\n run: |\n npm i -g pnpm@next-7\n time make test-e2e-pnpm\n\n - name: Test yarn (classic)\n run: |\n npm i -g yarn@latest\n time make test-e2e-yarn\n\n - name: Test yarn (berry)\n run: |\n npm i -g yarn@latest\n time make test-e2e-yarn-berry\n\n - name: Test deno\n run: |\n time make test-e2e-deno\n" }, { "path": ".github/workflows/publish.yml", "content": "name: Publish\n\npermissions:\n id-token: write\n contents: write\n\non:\n push:\n branches:\n - main\n paths:\n - version.txt\n\njobs:\n publish:\n runs-on: ubuntu-latest\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Read version info\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $GITHUB_ENV\n echo \"ESBUILD_VERSION=$(cat version.txt)\" >> $GITHUB_ENV\n\n # This is here to fail quickly if the release already exists\n - name: Try to create the \"v${{ env.ESBUILD_VERSION }}\" tag\n run: |\n git fetch --tags\n git tag \"v$ESBUILD_VERSION\"\n\n - name: Extract the release notes\n run: |\n CHANGELOG=$(awk -v \"ver=$ESBUILD_VERSION\" '/^## / { if (p) { exit }; if ($2 == ver) { p=1; next} } p' CHANGELOG.md)\n echo \"CHANGELOG<> $GITHUB_ENV\n echo \"$CHANGELOG\" >> $GITHUB_ENV\n echo \"EOF\" >> $GITHUB_ENV\n\n # Make sure we'll be able to generate release notes later on below\n - name: Release notes must not be empty\n run: |\n test -n \"$CHANGELOG\"\n\n - name: Set up Go ${{ env.GO_VERSION }}\n uses: actions/setup-go@v3\n with:\n go-version: ${{ env.GO_VERSION }}\n\n - name: Setup Node.js environment\n uses: actions/setup-node@v3\n with:\n node-version: 24\n\n # This updates the version in all \"package.json\" files\n - name: Build for all platforms\n run: |\n make platform-all\n\n # All \"package.json\" files should have been updated already by running \"make platform-all\" and committing the results\n - name: Reject uncommitted/untracked changes\n run: |\n git status --porcelain\n test -z \"$(git status --porcelain)\"\n\n # Trusted publishing requires this specific version of npm\n - name: Install npm\n run: |\n npm install -g npm@11.5.1\n\n - name: Publish packages\n run: |\n make publish-all\n\n - name: Push the tag to GitHub\n run: |\n git push origin tag \"v$ESBUILD_VERSION\"\n\n # Only do this after publishing was successful\n - name: Create a GitHub Release\n uses: actions/create-release@v1\n env:\n GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}\n with:\n tag_name: v${{ env.ESBUILD_VERSION }}\n release_name: v${{ env.ESBUILD_VERSION }}\n body: ${{ env.CHANGELOG }}\n draft: false\n prerelease: false\n" }, { "path": ".github/workflows/validate.yml", "content": "name: Validate release builds\n\non:\n push:\n tags: ['v*']\n workflow_dispatch:\n\npermissions:\n contents: read # to fetch code (actions/checkout)\n\njobs:\n release:\n runs-on: ubuntu-latest\n steps:\n - name: Checkout code\n uses: actions/checkout@v3\n\n - name: Read go.version\n run: |\n echo \"GO_VERSION=$(cat go.version)\" >> $GITHUB_ENV\n\n - name: Set up Go 1.x\n uses: actions/setup-go@v3\n with:\n go-version: ${{ env.GO_VERSION }}\n id: go\n\n - name: Validation checks\n run: |\n make validate-builds\n" }, { "path": ".gitignore", "content": ".DS_Store\n.idea/\n.vscode/\n/bench/\n/demo/\n/deno/\n/esbuild\n/github/\n/go/\n/lib/deno/lib.deno.d.ts\n/npm/@esbuild/android-arm/esbuild.wasm\n/npm/@esbuild/android-arm/wasm_exec_node.js\n/npm/@esbuild/android-arm/wasm_exec.js\n/npm/@esbuild/android-x64/esbuild.wasm\n/npm/@esbuild/android-x64/wasm_exec_node.js\n/npm/@esbuild/android-x64/wasm_exec.js\n/npm/@esbuild/openharmony-arm64/esbuild.wasm\n/npm/@esbuild/openharmony-arm64/wasm_exec_node.js\n/npm/@esbuild/openharmony-arm64/wasm_exec.js\n/npm/@esbuild/wasi-preview1/esbuild.wasm\n/npm/esbuild-wasm/browser.js\n/npm/esbuild-wasm/esbuild.wasm\n/npm/esbuild-wasm/esm/\n/npm/esbuild-wasm/lib/\n/npm/esbuild-wasm/wasm_exec_node.js\n/npm/esbuild-wasm/wasm_exec.js\n/npm/esbuild/install.js\n/npm/esbuild/lib/\n/require/*/bench/\n/require/*/demo/\n/scripts/.*/\n/validate/\n/www\nbin\nesbuild.exe\nnode_modules/\n" }, { "path": "CHANGELOG-2020.md", "content": "# Changelog: 2020\n\nThis changelog documents all esbuild versions published in the year 2020 (versions 0.3.0 through 0.8.28).\n\n## 0.8.28\n\n* Add a `--summary` flag that prints helpful information after a build ([#631](https://github.com/evanw/esbuild/issues/631))\n\n Normally esbuild's CLI doesn't print anything after doing a build if nothing went wrong. This allows esbuild to be used as part of a more complex chain of tools without the output cluttering the terminal. However, sometimes it is nice to have a quick overview in your terminal of what the build just did. You can now add the `--summary` flag when using the CLI and esbuild will print a summary of what the build generated. It looks something like this:\n\n ```\n $ ./esbuild --summary --bundle src/Three.js --outfile=build/three.js --sourcemap\n\n build/three.js 1.0mb ⚠️\n build/three.js.map 1.8mb\n\n ⚡ Done in 43ms\n ```\n\n* Keep unused imports in TypeScript code in one specific case ([#604](https://github.com/evanw/esbuild/issues/604))\n\n The official TypeScript compiler always removes imported symbols that aren't used as values when converting TypeScript to JavaScript. This is because these symbols could be types and not removing them could result in a run-time module instantiation failure because of missing exports. This even happens when the `tsconfig.json` setting `\"importsNotUsedAsValues\"` is set to `\"preserve\"`. Doing this just keeps the import statement itself but confusingly still removes the imports that aren't used as values.\n\n Previously esbuild always exactly matched the behavior of the official TypeScript compiler regarding import removal. However, that is problematic when trying to use esbuild to compile a partial module such as when converting TypeScript to JavaScript inside a file written in the [Svelte](https://svelte.dev/) programming language. Here is an example:\n\n ```html\n \n
\n

Hello {name}!

\n \n
\n ```\n\n The current Svelte compiler plugin for TypeScript only provides esbuild with the contents of the `\n \n ```\n\n In addition to this approach, you can now also use esbuild in the browser from a module-type script (note the use of `esm/browser.js` instead of `lib/browser.js`):\n\n ```html\n \n ```\n\n Part of this fix was contributed by [@calebeby](https://github.com/calebeby).\n\n## 0.7.16\n\n* Fix backward slashes in source maps on Windows ([#463](https://github.com/evanw/esbuild/issues/463))\n\n The relative path fix in the previous release caused a regression where paths in source maps contained `\\` instead of `/` on Windows. That is incorrect because source map paths are URLs, not file system paths. This release replaces `\\` with `/` for consistency on Windows.\n\n* `module.require()` is now an alias for `require()` ([#455](https://github.com/evanw/esbuild/issues/455))\n\n Some packages such as [apollo-server](https://github.com/apollographql/apollo-server) use `module.require()` instead of `require()` with the intent of bypassing the bundler's `require` and calling the underlying function from `node` instead. Unfortunately that doesn't actually work because CommonJS module semantics means `module` is a variable local to that file's CommonJS closure instead of the host's `module` object.\n\n This wasn't an issue when using `apollo-server` with Webpack because the literal expression `module.require()` is automatically rewritten to `require()` by Webpack: [webpack/webpack#7750](https://github.com/webpack/webpack/pull/7750). To get this package to work, esbuild now matches Webpack's behavior here. Calls to `module.require()` will become external calls to `require()` as long as the required path has been marked as external.\n\n## 0.7.15\n\n* Lower `export * as` syntax for ES2019 and below\n\n The `export * from 'path'` syntax was added in ES2015 but the `export * as name from 'path'` syntax was added more recently in ES2020. This is a shorthand for an import followed by an export:\n\n ```js\n // ES2020\n export * as name from 'path'\n\n // ES2019\n import * as name from 'path'\n export {name}\n ```\n\n With this release, esbuild will now undo this shorthand syntax when using `--target=es2019` or below.\n\n* Better code generation for TypeScript files with type-only exports ([#447](https://github.com/evanw/esbuild/issues/447))\n\n Previously TypeScript files could have an unnecessary CommonJS wrapper in certain situations. The specific situation is bundling a file that re-exports something from another file without any exports. This happens because esbuild automatically considers a module to be a CommonJS module if there is no ES6 `import`/`export` syntax.\n\n This behavior is undesirable because the CommonJS wrapper is usually unnecessary. It's especially undesirable for cases where the re-export uses `export * from` because then the re-exporting module is also converted to a CommonJS wrapper (since re-exporting everything from a CommonJS module must be done at run-time). That can also impact the bundle's exports itself if the entry point does this and the format is `esm`.\n\n It is generally equivalent to avoid the CommonJS wrapper and just rewrite the imports to an `undefined` literal instead:\n\n ```js\n import {name} from './empty-file'\n console.log(name)\n ```\n\n This can be rewritten to this instead (with a warning generated about `name` being missing):\n\n ```js\n console.log(void 0)\n ```\n\n With this release, this is now how cases like these are handled. The only case where this can't be done is when the import uses the `import * as` syntax. In that case a CommonJS wrapper is still necessary because the namespace cannot be rewritten to `undefined`.\n\n* Add support for `importsNotUsedAsValues` in TypeScript ([#448](https://github.com/evanw/esbuild/issues/448))\n\n The `importsNotUsedAsValues` field in `tsconfig.json` is now respected. Setting it to `\"preserve\"` means esbuild will no longer remove unused imports in TypeScript files. This field was added in TypeScript 3.8.\n\n* Fix relative paths in generated source maps ([#444](https://github.com/evanw/esbuild/issues/444))\n\n Currently paths in generated source map files don't necessarily correspond to real file system paths. They are really only meant to be human-readable when debugging in the browser.\n\n However, the Visual Studio Code debugger expects these paths to point back to the original files on the file system. With this release, it should now always be possible to get back to the original source file by joining the directory containing the source map file with the relative path in the source map.\n\n This fix was contributed by [@yoyo930021](https://github.com/yoyo930021).\n\n## 0.7.14\n\n* Fix a bug with compound import statements ([#446](https://github.com/evanw/esbuild/issues/446))\n\n Import statements can simultaneously contain both a default import and a namespace import like this:\n\n ```js\n import defVal, * as nsVal from 'path'\n ```\n\n These statements were previously miscompiled when bundling if the import path was marked as external, or when converting to a specific output format, and the namespace variable itself was used for something other than a property access. The generated code contained a syntax error because it generated a `{...}` import clause containing the default import.\n\n This particular problem was caused by code that converts namespace imports into import clauses for more efficient bundling. This transformation should not be done if the namespace import cannot be completely removed:\n\n ```js\n // Can convert namespace to clause\n import defVal, * as nsVal from 'path'\n console.log(defVal, nsVal.prop)\n ```\n\n ```js\n // Cannot convert namespace to clause\n import defVal, * as nsVal from 'path'\n console.log(defVal, nsVal)\n ```\n\n## 0.7.13\n\n* Fix `mainFields` in the JavaScript API ([#440](https://github.com/evanw/esbuild/issues/440) and [#441](https://github.com/evanw/esbuild/pull/441))\n\n It turns out the JavaScript bindings for the `mainFields` API option didn't work due to a copy/paste error. The fix for this was contributed by [@yoyo930021](https://github.com/yoyo930021).\n\n* The benchmarks have been updated\n\n The benchmarks now include Parcel 2 and Webpack 5 (in addition to Parcel 1 and Webpack 4, which were already included). It looks like Parcel 2 is slightly faster than Parcel 1 and Webpack 5 is significantly slower than Webpack 4.\n\n## 0.7.12\n\n* Fix another subtle ordering issue with `import` statements\n\n When importing a file while bundling, the import statement was ordered before the imported code. This could affect import execution order in complex scenarios involving nested hybrid ES6/CommonJS modules. The fix was to move the import statement to after the imported code instead. This issue affected the `@sentry/browser` package.\n\n## 0.7.11\n\n* Fix regression in 0.7.9 when minifying with code splitting ([#437](https://github.com/evanw/esbuild/issues/437))\n\n In certain specific cases, bundling and minifying with code splitting active can cause a crash. This is a regression that was introduced in version 0.7.9 due to the fix for issue [#421](https://github.com/evanw/esbuild/issues/421). The crash has been fixed and this case now has test coverage.\n\n## 0.7.10\n\n* Recover from bad `main` field in `package.json` ([#423](https://github.com/evanw/esbuild/issues/423))\n\n Some packages are published with invalid information in the `main` field of `package.json`. In that case, path resolution should fall back to searching for a file named `index.js` before giving up. This matters for the `simple-exiftool` package, for example.\n\n* Ignore TypeScript types on `catch` clause bindings ([435](https://github.com/evanw/esbuild/issues/435))\n\n This fixes an issue where using a type annotation in a `catch` clause like this was a syntax error:\n\n ```ts\n try {\n } catch (x: unknown) {\n }\n ```\n\n## 0.7.9\n\n* Fixed panic when using a `url()` import in CSS with the `--metafile` option\n\n This release fixes a crash that happens when `metafile` output is enabled and the `url()` syntax is used in a CSS file to import a successfully-resolved file.\n\n* Minify some CSS colors\n\n The minifier can now reduce the size of some CSS colors. This is the initial work to start CSS minification in general beyond whitespace removal. There is currently support for minifying hex, `rgb()/rgba()`, and `hsl()/hsla()` into hex or shorthand hex. The minification process respects the configured target browser and doesn't use any syntax that wouldn't be supported.\n\n* Lower newer CSS syntax for older browsers\n\n Newer color syntax such as `rgba(255 0 0 / 50%)` will be converted to older syntax (in this case `rgba(255, 0, 0, 0.5)`) when the target browser doesn't support the newer syntax. For example, this happens when using `--target=chrome60`.\n\n* Fix an ordering issue with `import` statements ([#421](https://github.com/evanw/esbuild/issues/421))\n\n Previously `import` statements that resolved to a CommonJS module turned into a call to `require()` inline. This was subtly incorrect when combined with tree shaking because it could sometimes cause imported modules to be reordered:\n\n ```js\n import {foo} from './cjs-file'\n import {bar} from './esm-file'\n console.log(foo, bar)\n ```\n\n That code was previously compiled into something like this, which is incorrect because the evaluation of `bar` may depend on side effects from importing `cjs-file.js`:\n\n ```js\n // ./cjs-file.js\n var require_cjs_file = __commonJS(() => {\n ...\n })\n\n // ./esm-file.js\n let bar = ...;\n\n // ./example.js\n const cjs_file = __toModule(require_cjs_file())\n console.log(cjs_file.foo, bar)\n ```\n\n That code is now compiled into something like this:\n\n ```js\n // ./cjs-file.js\n var require_cjs_file = __commonJS(() => {\n ...\n })\n\n // ./example.js\n const cjs_file = __toModule(require_cjs_file())\n\n // ./esm-file.js\n let bar = ...;\n\n // ./example.js\n console.log(cjs_file.foo, bar)\n ```\n\n This now means that a single input file can end up in multiple discontiguous regions in the output file as is the case with `example.js` here, which wasn't the case before this bug fix.\n\n## 0.7.8\n\n* Move external `@import` rules to the top\n\n Bundling could cause `@import` rules for paths that have been marked as external to be inserted in the middle of the CSS file. This would cause them to become invalid and be ignored by the browser since all `@import` rules must come first at the top of the file. These `@import` rules are now always moved to the top of the file so they stay valid.\n\n* Better support for `@keyframes` rules\n\n The parser now directly understands `@keyframes` rules, which means it can now format them more accurately and report more specific syntax errors.\n\n* Minify whitespace around commas in CSS\n\n Whitespace around commas in CSS will now be pretty-printed when not minifying and removed when minifying. So `a , b` becomes `a, b` when pretty-printed and `a,b` when minified.\n\n* Warn about unknown at-rules in CSS\n\n Using an `@rule` in a CSS file that isn't known by esbuild now generates a warning and these rules will be passed through unmodified. If they aren't known to esbuild, they are probably part of a CSS preprocessor syntax that should have been compiled away before giving the file to esbuild to parse.\n\n* Recoverable CSS syntax errors are now warnings\n\n The base CSS syntax can preserve nonsensical rules as long as they contain valid tokens and have matching opening and closing brackets. These rule with incorrect syntax now generate a warning instead of an error and esbuild preserves the syntax in the output file. This makes it possible to use esbuild to process CSS that was generated by another tool that contains bugs.\n\n For example, the following code is invalid CSS, and was presumably generated by a bug in an automatic prefix generator:\n\n ```css\n div {\n -webkit-undefined;\n -moz-undefined;\n -undefined;\n }\n ```\n\n This code will no longer prevent esbuild from processing the CSS file.\n\n* Treat `url(...)` in CSS files as an import ([#415](https://github.com/evanw/esbuild/issues/415))\n\n When bundling, the `url(...)` syntax in CSS now tries to resolve the URL as a path using the bundler's built in path resolution logic. The following loaders can be used with this syntax: `text`, `base64`, `file`, `dataurl`, and `binary`.\n\n* Automatically treat certain paths as external\n\n The following path forms are now automatically considered external:\n\n * `http://example.com/image.png`\n * `https://example.com/image.png`\n * `//example.com/image.png`\n * `data:image/png;base64,iVBORw0KGgo=`\n\n In addition, paths starting with `#` are considered external in CSS files, which allows the following syntax to continue to work:\n\n ```css\n path {\n /* This can be useful with SVG DOM content */\n fill: url(#filter);\n }\n ```\n\n## 0.7.7\n\n* Fix TypeScript decorators on static members\n\n This release fixes a bug with the TypeScript transform for the `experimentalDecorators` setting. Previously the target object for all decorators was the class prototype, which was incorrect for static members. Static members now correctly use the class object itself as a target object.\n\n* Experimental support for CSS syntax ([#20](https://github.com/evanw/esbuild/issues/20))\n\n This release introduces the new `css` loader, enabled by default for `.css` files. It has the following features:\n\n * You can now use esbuild to process CSS files by passing a CSS file as an entry point. This means CSS is a new first-class file type and you can use it without involving any JavaScript code at all.\n\n * When bundling is enabled, esbuild will bundle multiple CSS files together if they are referenced using the `@import \"./file.css\";` syntax. CSS files can be excluded from the bundle by marking them as external similar to JavaScript files.\n\n * There is basic support for pretty-printing CSS, and for whitespace removal when the `--minify` flag is present. There isn't any support for CSS syntax compression yet. Note that pretty-printing and whitespace removal both rely on the CSS syntax being recognized. Currently esbuild only recognizes certain CSS syntax and passes through unrecognized syntax unchanged.\n\n Some things to keep in mind:\n\n * CSS support is a significant undertaking and this is the very first release. There are almost certainly going to be issues. This is an experimental release to land the code and get feedback.\n\n * There is no support for CSS modules yet. Right now all class names are in the global namespace. Importing a CSS file into a JavaScript file will not result in any import names.\n\n * There is currently no support for code splitting of CSS. I haven't tested multiple entry-point scenarios yet and code splitting will require additional changes to the AST format.\n\n## 0.7.6\n\n* Fix JSON files with multiple entry points ([#413](https://github.com/evanw/esbuild/issues/413))\n\n This release fixes an issue where a single build operation containing multiple entry points and a shared JSON file which is used by more than one of those entry points can generate incorrect code for the JSON file when code splitting is disabled. The problem was not cloning the AST representing the JSON file before mutating it.\n\n* Silence warnings about `require.resolve()` for external paths ([#410](https://github.com/evanw/esbuild/issues/410))\n\n Bundling code containing a call to node's [`require.resolve()`](https://nodejs.org/api/modules.html#modules_require_resolve_request_options) function causes a warning because it's an unsupported use of `require` that does not end up being bundled. For example, the following code will likely have unexpected behavior if `foo` ends up being bundled because the `require()` call is evaluated at bundle time but the `require.resolve()` call is evaluated at run time:\n\n ```js\n let foo = {\n path: require.resolve('foo'),\n module: require('foo'),\n };\n ```\n\n These warnings can already be disabled by surrounding the code with a `try`/`catch` statement. With this release, these warnings can now also be disabled by marking the path as external.\n\n* Ensure external relative paths start with `./` or `../`\n\n Individual file paths can be marked as external in addition to package paths. In that case, the path to the file is rewritten to be relative to the output directory. However, previously the relative path for files in the output directory itself did not start with `./`, meaning they could potentially be interpreted as a package path instead of a relative path. These paths are now prefixed with `./` to avoid this edge case.\n\n## 0.7.5\n\n* Fix an issue with automatic semicolon insertion after `let` ([#409](https://github.com/evanw/esbuild/issues/409))\n\n The character sequence `let` can be considered either a keyword or an identifier depending on the context. A fix was previously landed in version 0.6.31 to consider `let` as an identifier in code like this:\n\n ```js\n if (0) let\n x = 0\n ```\n\n Handling this edge case is useless but the behavior is required by the specification. However, that fix also unintentionally caused `let` to be considered an identifier in code like this:\n\n ```js\n let\n x = 0\n ```\n\n In this case, `let` should be considered a keyword instead. This has been fixed.\n\n* Fix some additional conformance tests\n\n Some additional syntax edge cases are now forbidden including `let let`, `import {eval} from 'path'`, and `if (1) x: function f() {}`.\n\n## 0.7.4\n\n* Undo an earlier change to try to improve yarn compatibility ([#91](https://github.com/evanw/esbuild/pull/91) and [#407](https://github.com/evanw/esbuild/issues/407))\n\n The [yarn package manager](https://github.com/yarnpkg/yarn) behaves differently from npm and is not compatible in many ways. While npm is the only officially supported package manager for esbuild, people have contributed fixes for other package managers including yarn. One such fix is PR [#91](https://github.com/evanw/esbuild/pull/91) which makes sure the install script only runs once for a given installation directory.\n\n I suspect this fix is actually incorrect, and is the cause of issue [#407](https://github.com/evanw/esbuild/issues/407). The problem seems to be that if you change the version of a package using `yarn add esbuild@version`, yarn doesn't clear out the installation directory before reinstalling the package so the package ends up with a mix of files from both package versions. This is not how npm behaves and seems like a pretty severe bug in yarn. I am reverting PR [#91](https://github.com/evanw/esbuild/pull/91) in an attempt to fix this issue.\n\n* Disable some warnings for code inside `node_modules` directories ([#395](https://github.com/evanw/esbuild/issues/395) and [#402](https://github.com/evanw/esbuild/issues/402))\n\n Using esbuild to build code with certain suspicious-looking syntax may generate a warning. These warnings don't fail the build (the build still succeeds) but they point out code that is very likely to not behave as intended. This has caught real bugs in the past:\n\n * [rollup/rollup#3729](https://github.com/rollup/rollup/issues/3729): Invalid dead code removal for return statement due to ASI\n * [aws/aws-sdk-js#3325](https://github.com/aws/aws-sdk-js/issues/3325): Array equality bug in the Node.js XML parser\n * [olifolkerd/tabulator#2962](https://github.com/olifolkerd/tabulator/issues/2962): Nonsensical comparisons with typeof and \"null\"\n * [mrdoob/three.js#11183](https://github.com/mrdoob/three.js/pull/11183): Comparison with -0 in Math.js\n * [mrdoob/three.js#11182](https://github.com/mrdoob/three.js/pull/11182): Operator precedence bug in WWOBJLoader2.js\n\n However, it's not esbuild's job to find bugs in other libraries, and these warnings are problematic for people using these libraries with esbuild. The only fix is to either disable all esbuild warnings and not get warnings about your own code, or to try to get the warning fixed in the affected library. This is especially annoying if the warning is a false positive as was the case in https://github.com/firebase/firebase-js-sdk/issues/3814. So these warnings are now disabled for code inside `node_modules` directories.\n\n## 0.7.3\n\n* Fix compile error due to missing `unix.SYS_IOCTL` in the latest `golang.org/x/sys` ([#396](https://github.com/evanw/esbuild/pull/396))\n\n The `unix.SYS_IOCTL` export was apparently removed from `golang.org/x/sys` recently, which affected code in esbuild that gets the width of the terminal. This code now uses another method of getting the terminal width. The fix was contributed by [@akayj](https://github.com/akayj).\n\n* Validate that the versions of the host code and the binary executable match ([#407](https://github.com/evanw/esbuild/issues/407))\n\n After the install script runs, the version of the downloaded binary should always match the version of the package being installed. I have added some additional checks to verify this in case this invariant is ever broken. Breaking this invariant is very bad because it means the code being run is a mix of code from different package versions.\n\n## 0.7.2\n\n* Transform arrow functions to function expressions with `--target=es5` ([#182](https://github.com/evanw/esbuild/issues/182) and [#297](https://github.com/evanw/esbuild/issues/297))\n\n Arrow functions are now transformed into function expressions when targeting `es5`. For example, this code:\n\n ```js\n function foo() {\n var x = () => [this, arguments]\n return x()\n }\n ```\n\n is transformed into this code:\n\n ```js\n function foo() {\n var _this = this, _arguments = arguments;\n var x = function() {\n return [_this, _arguments];\n };\n return x();\n }\n ```\n\n* Parse template literal types from TypeScript 4.1\n\n TypeScript 4.1 includes a new feature called template literal types. You can read [the announcement](https://devblogs.microsoft.com/typescript/announcing-typescript-4-1-beta/#template-literal-types) for more details. The following syntax can now be parsed correctly by esbuild:\n\n ```ts\n let foo: `${'a' | 'b'}-${'c' | 'd'}` = 'a-c'\n ```\n\n* Parse key remapping in mapped types from TypeScript 4.1\n\n TypeScript 4.1 includes a new feature called key remapping in mapped types. You can read [the announcement](https://devblogs.microsoft.com/typescript/announcing-typescript-4-1-beta/#key-remapping-mapped-types) for more details. The following syntax can now be parsed correctly by esbuild:\n\n ```ts\n type RemoveField = { [K in keyof T as Exclude]: T[K] }\n ```\n\n* Allow automatic semicolon insertion before the TypeScript `as` operator\n\n The following code now correctly parses as two separate statements instead of one statement with a newline in the middle:\n\n ```ts\n let foo = bar\n as (null);\n ```\n\n* Fix a bug where `module` was incorrectly minified for non-JavaScript loaders\n\n If you pass a non-JavaScript file such as a `.json` file to esbuild, it will by default generate `module.exports = {...}`. However, the `module` variable would incorrectly be minified when `--minify` is present. This issue has been fixed. This bug did not appear if `--format=cjs` was also present, only if no `--format` flag was specified.\n\n* Fix bugs with `async` functions ([#388](https://github.com/evanw/esbuild/issues/388))\n\n This release contains correctness fixes for `async` arrow functions with regard to the `arguments` variable. This affected `async` arrow functions nested inside `function` expressions or statements. Part of this fix was contributed by [@rtsao](https://github.com/rtsao).\n\n* Fix `export` clause when converting to CommonJS in transform API calls ([#393](https://github.com/evanw/esbuild/issues/393))\n\n This release fixes some bugs with the recently-released feature in version 0.6.32 where you can specify an output format even when bundling is disabled. This is the case when using the transform API call, for example. Previously esbuild could generate code that crashed at run time while trying to export something incorrectly. This only affected code with top-level `export` statements. This has been fixed and these cases now have test coverage.\n\n## 0.7.1\n\n* Fix bug that forbids `undefined` values in the JavaScript API\n\n The validation added in the previous release was accidentally overly restrictive and forbids `undefined` values for optional properties. This release allows `undefined` values again (which are simply ignored).\n\n## 0.7.0\n\n* Mark output files with a hashbang as executable ([#364](https://github.com/evanw/esbuild/issues/364))\n\n Output files that start with a hashbang line such as `#!/usr/bin/env node` will now automatically be marked as executable. This lets you run them directly in a Unix-like shell without using the `node` command.\n\n* Use `\"main\"` for `require()` and `\"module\"` for `import` ([#363](https://github.com/evanw/esbuild/issues/363))\n\n The [node module resolution algorithm](https://nodejs.org/api/modules.html#modules_all_together) uses the `\"main\"` field in `package.json` to determine which file to load when a package is loaded with `require()`. Independent of node, most bundlers have converged on a convention where the `\"module\"` field takes precedence over the `\"main\"` field when present. Package authors can then use the `\"module\"` field to publish the same code in a different format for bundlers than for node.\n\n This is commonly used to publish \"dual packages\" that appear to use ECMAScript modules to bundlers but that appear to use CommonJS modules to node. This is useful because ECMAScript modules improve bundler output by taking advantage of \"tree shaking\" (basically dead-code elimination) and because ECMAScript modules cause lots of problems in node (for example, node doesn't support importing ECMAScript modules using `require()`).\n\n The problem is that if code using `require()` resolves to the `\"module\"` field in esbuild, the resulting value is currently always an object. ECMAScript modules export a namespace containing all exported properties. There is no direct equivalent of `module.exports = value` in CommonJS. The closest is `export default value` but the CommonJS equivalent of that is `exports.default = value`. This is problematic for code containing `module.exports = function() {}` which is a frequently-used CommonJS library pattern. An example of such an issue is Webpack issue [#6584](https://github.com/webpack/webpack/issues/6584).\n\n An often-proposed way to fix this is to map `require()` to `\"main\"` and map `import` to `\"module\"`. The problem with this is that it means the same package would be loaded into memory more than once if it is loaded both with `require()` and with `import` (perhaps from separate packages). An example of such an issue is GraphQL issue [#1479](https://github.com/graphql/graphql-js/issues/1479#issuecomment-416718578).\n\n The workaround for these problems in this release is that esbuild will now exclusively use `\"main\"` for a package that is loaded using `require()` at least once. Otherwise, if a package is only loaded using `import`, esbuild will exclusively use the `\"module\"` field. This still takes advantage of tree shaking for ECMAScript modules but gracefully falls back to CommonJS for compatibility.\n\n Keep in mind that the [`\"browser\"` field](https://github.com/defunctzombie/package-browser-field-spec) still takes precedence over both `\"module\"` and `\"main\"` when building for the browser platform.\n\n* Add the `--main-fields=` flag ([#363](https://github.com/evanw/esbuild/issues/363))\n\n This adopts a configuration option from Webpack that lets you specify the order of \"main fields\" from `package.json` to use when determining the main module file for a package. Node only uses `main` but bundlers often respect other ones too such as `module` or `browser`. You can read more about this feature in the Webpack documentation [here](https://webpack.js.org/configuration/resolve/#resolvemainfields).\n\n The default order when targeting the browser is essentially `browser,module,main` with the caveat that `main` may be chosen over `module` for CommonJS compatibility as described above. If choosing `module` over `main` at the expense of CommonJS compatibility is important to you, this behavior can be disabled by explicitly specifying `--main-fields=browser,module,main`.\n\n The default order when targeting node is `main,module`. Note that this is different than Webpack, which defaults to `module,main`. This is also for compatibility because some packages incorrectly treat `module` as meaning \"code for the browser\" instead of what it actually means, which is \"code for ES6 environments\". Unfortunately this disables most tree shaking that would otherwise be possible because it means CommonJS modules will be chosen over ECMAScript modules. If choosing `module` over `main` is important to you (e.g. to potentially take advantage of improved tree shaking), this behavior can be disabled by explicitly specifying `--main-fields=module,main`.\n\n* Additional validation of arguments to JavaScript API calls ([#381](https://github.com/evanw/esbuild/issues/381))\n\n JavaScript API calls each take an object with many optional properties as an argument. Previously there was only minimal validation of the contents of that object. If you aren't using TypeScript, this can lead to confusing situations when the data on the object is invalid. Now there is some additional validation done to the shape of the object and the types of the properties.\n\n It is now an error to pass an object with a property that esbuild won't use. This should help to catch typos. It is also now an error if a property on the object has an unexpected type.\n\n## 0.6.34\n\n* Fix parsing of `type;` statements followed by an identifier in TypeScript ([#377](https://github.com/evanw/esbuild/pull/377))\n\n The following TypeScript code is now correctly parsed as two separate expression statements instead of one type declaration statement:\n\n ```ts\n type\n Foo = {}\n ```\n\n This was contributed by [@rtsao](https://github.com/rtsao).\n\n* Fix `export {Type}` in TypeScript when bundling ([#379](https://github.com/evanw/esbuild/issues/379))\n\n In TypeScript, `export {Type}` is supposed to be silently removed by the compiler if `Type` does not refer to a value declared locally in the file. Previously this behavior was incompletely implemented. The statement itself was removed but the export record was not, so later stages of the pipeline could sometimes add the export statement back. This release removes the export record as well as the statement so it should stay removed in all cases.\n\n* Forbid exporting non-local symbols in JavaScript\n\n It is now an error to export an identifier using `export {foo}` if `foo` is not declared locally in the same file. This error matches the error that would happen at run-time if the code were to be evaluated in a JavaScript environment that supports ES6 module syntax. This is only an error in JavaScript. In TypeScript, the missing identifier is silently removed instead since it's assumed to be a type name.\n\n* Handle source maps with out-of-order mappings ([#378](https://github.com/evanw/esbuild/issues/378))\n\n Almost all tools that generate source maps write out the mappings in increasing order by generated position since the mappings are generated along with the output. However, some tools can apparently generate source maps with out-of-order mappings. It's impossible for generated line numbers to be out of order due to the way the source map format works, but it's possible for generated column numbers to be out of order. This release fixes this issue by sorting the mappings by generated position after parsing if necessary.\n\n## 0.6.33\n\n* Fix precedence of tagged template expressions ([#372](https://github.com/evanw/esbuild/issues/372))\n\n Previously `` await tag`text` `` and `` new tag`text` `` were incorrectly parsed as `` (await tag)`text` `` and `` (new tag)`text` ``. They are now correctly parsed as `` await (tag`text`) `` and `` new (tag`text`) `` instead.\n\n* Fix invalid syntax when lowering `super` inside `async` to `es2016` or earlier ([#375](https://github.com/evanw/esbuild/issues/375))\n\n This release fixes a bug where using `super.prop` inside an `async` function with `--target=es2016` or earlier generated code that contained a syntax error. This was because `async` functions are converted to generator functions inside a wrapper function in this case, and `super` is not available inside the wrapper function. The fix is to move the reference to `super` outside of the wrapper function.\n\n* Fix duplicate definition of `module` when targeting CommonJS ([#370](https://github.com/evanw/esbuild/issues/370))\n\n The bundler didn't properly reserve the identifier `module` when using `--format=cjs`. This meant automatically-generated variables named `module` could potentially not be renamed to avoid collisions with the CommonJS `module` variable. It was possible to get into this situation when importing a module named `module`, such as the [node built-in module by that name](https://nodejs.org/api/module.html). This name is now marked as reserved when bundling to CommonJS, so automatically-generated variables named `module` will now be renamed to `module2` to avoid collisions.\n\n## 0.6.32\n\n* Allow `--format` when bundling is disabled ([#109](https://github.com/evanw/esbuild/issues/109))\n\n This change means esbuild can be used to convert ES6 import and export syntax to CommonJS syntax. The following code:\n\n ```js\n import foo from 'foo'\n export const bar = foo\n ```\n\n will be transformed into the following code with `--format=cjs` (the code for `__export` and `__toModule` was omitted for brevity):\n\n ```js\n __export(exports, {\n bar: () => bar\n });\n const foo = __toModule(require(\"foo\"));\n const bar = foo.default;\n ```\n\n This also applies to non-JavaScript loaders too. The following JSON:\n\n ```json\n {\"foo\": true, \"bar\": false}\n ```\n\n is normally converted to the following code with `--loader=json`:\n\n ```js\n module.exports = {foo: true, bar: false};\n ```\n\n but will be transformed into the following code instead with `--loader=json --format=esm`:\n\n ```js\n var foo = true;\n var bar = false;\n var stdin_default = {foo, bar};\n export {\n bar,\n stdin_default as default,\n foo\n };\n ```\n\n Note that converting CommonJS `require()` calls to ES6 imports is not currently supported. Code containing a reference to `require` in these situations will generate a warning.\n\n* Change the flag for boolean and string minification ([#371](https://github.com/evanw/esbuild/issues/371))\n\n Previously setting the `--minify-whitespace` flag shortened `true` and `false` to `!0` and `!1` and shortened string literals containing many newlines by writing them as template literals instead. These shortening operations have been changed to the `--minify-syntax` flag instead. There is no change in behavior for the `--minify` flag because that flag already implies both `--minify-whitespace` and `--minify-syntax`.\n\n* Remove trailing `()` from `new` when minifying\n\n Now `new Foo()` will be printed as `new Foo` when minifying (as long as it's safe to do so), resulting in slightly shorter minified code.\n\n* Forbid `async` functions when the target is `es5`\n\n Previously using `async` functions did not cause a compile error when targeting `es5` since if they are unavailable, they are rewritten to use generator functions instead. However, generator functions may also be unsupported. It is now an error to use `async` functions if generator functions are unsupported.\n\n* Fix subtle issue with transforming `async` functions when targeting `es2016` or below\n\n The TypeScript compiler has a bug where, when the language target is set to `ES2016` or earlier, exceptions thrown during argument evaluation are incorrectly thrown immediately instead of later causing the returned promise to be rejected. Since esbuild replicates TypeScript's `async` function transformation pass, esbuild inherited this same bug. The behavior of esbuild has been changed to match the JavaScript specification.\n\n Here's an example of code that was affected:\n\n ```js\n async function test(value = getDefaultValue()) {}\n let promise = test()\n ```\n\n The call to `test()` here should never throw, even if `getDefaultValue()` throws an exception.\n\n## 0.6.31\n\n* Invalid source maps are no longer an error ([#367](https://github.com/evanw/esbuild/issues/367))\n\n Previously esbuild would fail the build with an error if it encountered a source map that failed validation according to [the specification](https://sourcemaps.info/spec.html). Now invalid source maps will be validated with an error-tolerant validator that will either silently ignore errors or generate a warning, but will never fail the build.\n\n* Fix various edge cases for conformance tests\n\n * Hoisted function declarations in nested scopes can now shadow symbols in the enclosing scope without a syntax error:\n\n ```js\n let foo\n {\n function foo() {}\n }\n ```\n\n * If statements directly containing function declarations now introduce a nested scope so this code is no longer a syntax error:\n\n ```js\n let foo\n if (true)\n function foo() {}\n ```\n\n * Keywords can now be used as export aliases with `export * as` statements:\n\n ```js\n export * as class from 'path'\n ```\n\n * It is now a syntax error to use `break` or `continue` in invalid locations:\n\n ```js\n function foo() { break }\n ```\n\n * Using `yield` as an identifier outside of a generator function is now allowed:\n\n ```js\n var yield = null\n ```\n\n * It is now a syntax error to use `yield` or `await` inside a generator or `async` function if it contains an escape sequence:\n\n ```js\n async function foo() {\n return \\u0061wait;\n }\n ```\n\n * It is now a syntax error to use an `import()` expression with the `new` operator without parentheses:\n\n ```js\n new import('path')\n ```\n\n * Using `let` as an identifier is now allowed:\n\n ```js\n let = null\n ```\n\n * It is no longer a compile-time error to assign to an import when not bundling:\n\n ```js\n import {foo} from 'path'\n foo = null\n ```\n\n Instead the behavior will be left up to the host environment at run-time, which should cause a run-time error. However, this will still be treated as a compile-time error when bundling because the scope-hoisting optimization that happens during bundling means the host may no longer cause run-time errors.\n\n * You can now declare a variable named `arguments` inside a function without an error:\n\n ```js\n function foo() {\n let arguments = null\n }\n ```\n\n * Comma expressions in the iterable position of for-of loops are now a syntax error:\n\n ```js\n for (var a of b, c) {\n }\n ```\n\n * It is now a syntax error to use `||` or `&&` with `??` without parentheses\n\n ```js\n a ?? b || c // Syntax error\n a ?? (b || c) // Allowed\n (a ?? b) || c // Allowed\n ```\n\n * It is now a syntax error to use `arguments` inside a `class` field initializer\n\n ```js\n class Foo {\n foo = arguments\n }\n ```\n\n * It is now a syntax error to a strict mode reserved word to name a `class`\n\n ```js\n class static {}\n ```\n\n## 0.6.30\n\n* Fix optional call of `super` property ([#362](https://github.com/evanw/esbuild/issues/362))\n\n This fixes a bug where lowering the code `super.foo?.()` was incorrectly transformed to this:\n\n ```js\n var _a, _b;\n (_b = (_a = super).foo) == null ? void 0 : _b.call(_a);\n ```\n\n This is invalid code because a bare `super` keyword is not allowed. Now that code is transformed to this instead:\n\n ```js\n var _a;\n (_a = super.foo) == null ? void 0 : _a.call(this);\n ```\n\n* Add a `--strict:optional-chaining` option\n\n This affects the transform for the `?.` optional chaining operator. In loose mode (the default), `a?.b` is transformed to `a == null ? void 0 : a.b`. This works fine in all cases except when `a` is the special object `document.all`. In strict mode, `a?.b` is transformed to `a === null || a === void 0 ? void 0 : a.b` which works correctly with `document.all`. Enable `--strict:optional-chaining` if you need to use `document.all` with the `?.` operator.\n\n## 0.6.29\n\n* Add a warning for comparison with `NaN`\n\n This warning triggers for code such as `x === NaN`. Code that does this is almost certainly a bug because `NaN === NaN` is false in JavaScript.\n\n* Add a warning for duplicate switch case clauses\n\n This warning detects situations when multiple `case` clauses in the same `switch` statement match on the same expression. This almost certainly indicates a problem with the code. This warning protects against situations like this:\n\n ```js\n switch (typeof x) {\n case 'object':\n // ...\n case 'function':\n // ...\n case 'boolean':\n // ...\n case 'object':\n // ...\n }\n ```\n\n* Allow getters and setters in ES5 ([#356](https://github.com/evanw/esbuild/issues/356))\n\n This was an oversight. I incorrectly thought getters and setters were added in ES6, not in ES5. This release allows getter and setter method syntax even when `--target=es5`.\n\n* Fix a Windows-only regression with missing directory errors ([#359](https://github.com/evanw/esbuild/issues/359))\n\n Various Go file system APIs return `ENOTDIR` for missing file system entries on Windows instead of `ENOENT` like they do on other platforms. This interfered with code added in the previous release that makes unexpected file system errors no longer silent. `ENOTDIR` is usually an unexpected error because it's supposed to happen when the file system entry is present but just unexpectedly a file instead of a directory. This release changes `ENOTDIR` to `ENOENT` in certain cases so that these Windows-only errors are no longer treated as unexpected errors.\n\n* Enforce object accessor argument counts\n\n According to the JavaScript specification, getter methods must have zero arguments and setter methods must have exactly one argument. This release enforces these rules.\n\n* Validate assignment targets\n\n Code containing invalid assignments such as `1 = 2` will now be correctly rejected as a syntax error. Previously such code was passed through unmodified and the output file would contain a syntax error (i.e. \"garbage in, garbage out\").\n\n## 0.6.28\n\n* Avoid running out of file handles when ulimit is low ([#348](https://github.com/evanw/esbuild/issues/348))\n\n When esbuild uses aggressive concurrency, it can sometimes simultaneously use more file handles than allowed by the system. This can be a problem when the limit is low (e.g. using `ulimit -n 32`). In this release, esbuild now limits itself to using a maximum of 32 file operations simultaneously (in practice this may use up to 64 file handles since some file operations need two handles). This limit was chosen to be low enough to not cause issues with normal ulimit values but high enough to not impact benchmark times.\n\n* Unexpected file system errors are no longer silent ([#348](https://github.com/evanw/esbuild/issues/348))\n\n All file system errors were previously treated the same; any error meant the file or directory was considered to not exist. This was problematic when the process ran out of available file handles because it meant esbuild could ignore files that do actually exist if file handles are exhausted. Then esbuild could potentially generate a different output instead of failing with an error. Now if esbuild gets into this situation, it should report unexpected file system errors and fail to build instead of continuing to build and potentially producing incorrect output.\n\n* Install script tries `npm install` before a direct download ([#347](https://github.com/evanw/esbuild/issues/347))\n\n The `esbuild` package has a post-install script that downloads the native binary for the current platform over HTTP. Some people have configured their environments such that HTTP requests to npmjs.org will hang, and configured npm to use a proxy for HTTP requests instead. In this case, esbuild's install script will still work as long as `npm install` works because the HTTP request will eventually time out, at which point the install script will run `npm install` as a fallback. The timeout is of course undesirable.\n\n This release changes the order of attempted download methods in the install script. Now `npm install` is tried first and directly downloading the file over HTTP will be tried as a fallback. This means installations will be slightly slower since npm is slow, but it should avoid the situation where the install script takes a long time because it's waiting for a HTTP timeout. This should still support the scenarios where there is a HTTP proxy configured, where there is a custom registry configured, and where the `npm` command isn't available.\n\n## 0.6.27\n\n* Add parentheses when calling `require()` inside `new` ([#339](https://github.com/evanw/esbuild/issues/339))\n\n This release fixes an issue where `new (require('path')).ctor()` became `new require_path().ctor()` after bundling, which caused `require_path()` to be invoked as the constructor instead of `ctor()`. With this fix the code `new (require_path()).ctor()` is generated instead, which correctly invokes `ctor()` as the constructor. This was contributed by [@rtsao](https://github.com/rtsao).\n\n## 0.6.26\n\n* Fix syntax error when minifying and bundling CommonJS to ES5 ([#335](https://github.com/evanw/esbuild/issues/335))\n\n With the flags `--minify --bundle --target=es5`, esbuild had a bug where the arrow function for the closure used to wrap CommonJS modules was not correctly printed as an ES5 function expression, causing a syntax error. This bug has been fixed.\n\n## 0.6.25\n\n* Avoid the `\\v` escape sequence in JSON strings\n\n Source maps are JSON files, and must obey the [JSON specification](https://www.json.org/). The escape sequence `\\v` (for the ASCII control character 11) is valid in JavaScript but not in JSON. Previously esbuild contained a bug where source maps for files containing this ASCII control character were invalid JSON. This release fixes the bug by printing this character as `\\u000B` instead.\n\n* Speedup for `esbuild-wasm` when using the command line\n\n The [esbuild-wasm](https://www.npmjs.com/package/esbuild-wasm) package includes a WebAssembly command-line tool called `esbuild` which functions the same as the native command-line tool called `esbuild` in the [esbuild](https://www.npmjs.com/package/esbuild) package. The difference is that the WebAssembly implementation is around an order of magnitude slower than the native version.\n\n This release changes the API used to instantiate the WebAssembly module from [WebAssembly.instantiate](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WebAssembly/instantiate) to [WebAssembly.Module](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WebAssembly/Module/Module), which reduces end-to-end build time by around 1 second on my development laptop. The WebAssembly version is still much slower than the native version, but now it's a little faster than before.\n\n* Optimize for the [@material-ui/icons](https://www.npmjs.com/package/@material-ui/icons) package\n\n This package has a directory containing over 11,000 files. Certain optimizations in esbuild that worked fine for common cases severely impacted performance for this edge case. This release changes some aspects of path resolution caching to fix these problems. Build time for a certain benchmark involving this package improved from 1.01s for the previous release to 0.22s for this release. Other benchmark times appear to be unaffected.\n\n## 0.6.24\n\n* Switch from base64 encoding to base32 encoding for file hashes\n\n Certain output files contain hashes in their name both to prevent collisions and to improve caching. For example, an SVG file named `example.svg` that is loaded using the `file` loader might be copied to a file named `example.T3K5TRK4.svg` in the build directory. The hashes are based on the file's contents so they only change when the file content itself changes.\n\n The hashes previously used [base64 encoding](https://en.wikipedia.org/wiki/Base64) but I recently realized that since certain file systems (e.g. Windows) are case-insensitive, this could lead to confusing situations where esbuild could theoretically generate two files with different case-sensitive names but with the same case-insensitive name. Hashes now use [base32 encoding](https://en.wikipedia.org/wiki/Base32) which only includes uppercase letters, not lowercase letters, which should avoid this confusing situation.\n\n* Optimize character frequency for better gzip compression\n\n The character sequence used to generate minified names is now the characters in the input files sorted descending by frequency. Previously it was just the valid identifier characters in alphabetic order. This means minified names are more likely to contain characters found elsewhere in the output file (e.g. in keywords and strings). This is a pretty small win but it was added because it's a consistent win, it's simple to implement, and it's very fast to compute.\n\n* Minor syntax minification improvements\n\n This release contains these additional rules for syntax minification:\n\n * `a ? b : b` is minified to `a, b`\n * `a ? a : b` is minified to `a || b`\n * `a ? b : a` is minified to `a && b`\n * `a == void 0` is minified to `a == null`\n * `a && (b && c)` is minified to `a && b && c` (same for `||`)\n * `a ? c : (b, c)` is minified to `(a || b), c`\n * `a ? (b, c) : c` is minified to `(a && b), c`\n * `a ? b || c : c` is minified to `(a && b) || c`\n * `a ? c : b && c` is minified to `(a || b) && c`\n * `a ? b(c) : b(d)` is minified to `b(a ? c : d)`\n * `a ? true : false` is minified to `!!a`\n * `a != null ? a : b` is minified to `a ?? b` if it's supported in the target environment\n * `a ? (b ? c : d) : d` is minified to `(a && b) ? c : d`\n * `a ? b : (c ? b : d)` is minified to `(a || c) ? b : d`\n * `(function foo() {})` is minified to `(function() {})`\n * `typeof a === \"string\"` is minified to `typeof a == \"string\"`\n * `if (a) if (b) return c` is minified to `if (a && b) return c`\n * `while (a) if (!b) break;` is minified to `for (; a && b; ) ;`\n * `a === null || a === undefined` is minified to `a == null`\n\n These improvements cause minified code to be slightly smaller.\n\n## 0.6.23\n\n* Add an error message for a missing `--tsconfig` file ([#330](https://github.com/evanw/esbuild/issues/330))\n\n The `--tsconfig` flag that was added in version 0.6.1 didn't report an error if the provided file doesn't actually exist. This release makes doing this an error that will fail the build.\n\n* Avoid generating the minified label name `if` ([#332](https://github.com/evanw/esbuild/issues/332))\n\n The recent minification changes in 0.6.20 introduced a regression where input files containing 333 or more label statements resulted in a label being assigned the minified name `if`, which is a JavaScript keyword. This is the first JavaScript keyword in the minified name sequence that esbuild uses for label names: `a b c ... aa ba ca ...`. The regression has been fixed and there is now test coverage for this case.\n\n## 0.6.22\n\n* The bell character is now escaped\n\n In most terminals, printing the bell character (ASCII code 7) will trigger a sound. The macOS terminal will also flash the screen if sound is muted. This is annoying, and can happen when dumping the output of esbuild to the terminal if the input contains a bell character. Now esbuild will always escape bell characters in the output to avoid this problem.\n\n* CommonJS modules now export properties of prototype ([#326](https://github.com/evanw/esbuild/issues/326))\n\n This change is for compatibility with Webpack. You can now assign an object with a custom prototype to `module.exports` and esbuild will consider all enumerable properties on the prototype as exports. This behavior is necessary to correctly bundle the [paper.js](https://github.com/paperjs/paper.js) library, for example.\n\n## 0.6.21\n\n* Upgrade from Go 1.14 to Go 1.15\n\n This change isn't represented by a commit in the repo, but from now on I will be using Go 1.15 to build the distributed binaries instead of Go 1.14. The [release notes for Go 1.15](https://golang.org/doc/go1.15) mention improvements to binary size:\n\n > Go 1.15 reduces typical binary sizes by around 5% compared to Go 1.14 by eliminating certain types of GC metadata and more aggressively eliminating unused type metadata.\n\n Initial testing shows that upgrading Go reduces the esbuild binary size on macOS from 7.4mb to 5.3mb, which is a 30% smaller binary! I assume the binary size savings are similar for other platforms. Run-time performance on the esbuild benchmarks seems consistent with previous releases.\n\n* Lower non-tag template literals to ES5 ([#297](https://github.com/evanw/esbuild/issues/297))\n\n You can now use non-tag template literals such as `` `abc` `` and `` `a${b}c` `` with `--target=es5` and esbuild will convert them to string addition such as `\"abc\"` and `\"a\" + b + \"c\"` instead of reporting an error.\n\n* Newline normalization in template literals\n\n This fixes a bug with esbuild that caused carriage-return characters to incorrectly end up in multi-line template literals if the source file used Windows-style line endings (i.e. `\\r\\n`). The ES6 language specification says that both carriage-return characters and Windows carriage-return line-feed sequences must be converted to line-feed characters instead. With this change, esbuild's parsing of multi-line template literals should no longer be platform-dependent.\n\n* Fix minification bug with variable hoisting\n\n Hoisted variables that are declared with `var` in a nested scope but hoisted to the top-level scope were incorrectly minified as a nested scope symbol instead of a top-level symbol, which could potentially cause a name collision. This bug has been fixed.\n\n## 0.6.20\n\n* Symbols are now renamed separately per chunk ([#16](https://github.com/evanw/esbuild/issues/16))\n\n Previously, bundling with code splitting assigned minified names using a single frequency distribution calculated across all chunks. This meant that typical code changes in one chunk would often cause the contents of all chunks to change, which negated some of the benefits of the browser cache.\n\n Now symbol renaming (both minified and not minified) is done separately per chunk. It was challenging to implement this without making esbuild a lot slower and causing it to use a lot more memory. Symbol renaming has been mostly rewritten to accomplish this and appears to actually usually use a little less memory and run a bit faster than before, even for code splitting builds that generate a lot of chunks. In addition, minified chunks are now slightly smaller because a given minified name can now be reused by multiple chunks.\n\n## 0.6.19\n\n* Reduce memory usage for large builds by 30-40% ([#304](https://github.com/evanw/esbuild/issues/304))\n\n This release reduces memory usage. These specific percentages are likely only accurate for builds with a large number of files. Memory is reduced by ~30% for all builds by avoiding unnecessary per-file symbol maps, and is reduced by an additional ~10% for builds with source maps by preallocating some large arrays relating to source map output.\n\n* Replace `.js` and `.jsx` with `.ts` or `.tsx` when resolving ([#118](https://github.com/evanw/esbuild/issues/118))\n\n This adds an import path resolution behavior that's specific to the TypeScript compiler where you can use an import path that ends in `.js` or `.jsx` when the correct import path actually ends in `.ts` or `.tsx` instead. See the discussion here for more historical context: https://github.com/microsoft/TypeScript/issues/4595.\n\n## 0.6.18\n\n* Install script falls back to `npm install` ([#319](https://github.com/evanw/esbuild/issues/319))\n\n The `esbuild` package has a post-install script that downloads the esbuild binary. However, this will fail if `registry.npmjs.org` (or the configured custom npm registry) is inaccessible.\n\n This release adds an additional fallback for when the download fails. It tries to use the `npm install` command to download the esbuild binary instead. This handles situations where users have either configured npm with a proxy or have a custom command in their path called `npm`.\n\n## 0.6.17\n\n* Add a download cache to the install script\n\n This speeds up repeated esbuild installs for the same version by only downloading the binary from npm the first time and then reusing it for subsequent installs. The binary files are cached in these locations, which are the same locations as the Electron install script:\n\n * Windows: `%USERPROFILE%\\AppData\\Local\\Cache\\esbuild\\bin`\n * macOS: `~/Library/Caches/esbuild/bin`\n * Other: `~/.cache/esbuild/bin`\n\n The cache holds a maximum of 5 entries and purges least-recently-used entries above that limit.\n\n* Omit `export default` of local type names ([#316](https://github.com/evanw/esbuild/issues/316))\n\n Normally the `export default` syntax takes a value expression to export. However, TypeScript has a special case for `export default ` where the identifier is allowed to be a type expression instead of a value expression. In that case, the type expression should not be emitted in the resulting bundle. This release improves support for this case by omitting the export when the identifier matches a local type name.\n\n## 0.6.16\n\n* Colors for Windows console output\n\n Console output on Windows now uses color instead of being monochrome. This should make log messages easier to read.\n\n* Parenthesize destructuring assignment in arrow function expressions ([#313](https://github.com/evanw/esbuild/issues/313))\n\n This fixes a bug where `() => ({} = {})` was incorrectly printed as `() => ({}) = {}`, which is a syntax error. This case is now printed correctly.\n\n## 0.6.15\n\n* Support symlinks with absolute paths in `node_modules` ([#310](https://github.com/evanw/esbuild/issues/310))\n\n Previously esbuild only supported symlinks with relative paths, not absolute paths. Adding support for absolute paths in symlinks fixes issues with esbuild and [pnpm](https://github.com/pnpm/pnpm) on Windows.\n\n* Preserve leading comments inside `import()` expressions ([#309](https://github.com/evanw/esbuild/issues/309))\n\n This makes it possible to use esbuild as a faster TypeScript-to-JavaScript frontend for Webpack, which has special [magic comments](https://webpack.js.org/api/module-methods/#magic-comments) inside `import()` expressions that affect Webpack's behavior.\n\n* Fix crash for source files beginning with `\\r\\n` when using source maps ([#311](https://github.com/evanw/esbuild/issues/311))\n\n The source map changes in version 0.6.13 introduced a regression that caused source files beginning with `\\r\\n` to crash esbuild when source map generation was enabled. This was not caught during testing both because not many source files begin with a newline and not many source files have Windows-style line endings in them. This regression has been fixed and Windows-style line endings now have test coverage.\n\n## 0.6.14\n\n* Add support for parsing top-level await ([#253](https://github.com/evanw/esbuild/issues/253))\n\n It seems appropriate for esbuild to support top-level await syntax now that [node is supporting top-level await syntax by default](https://github.com/nodejs/node/issues/34551) (it's the first widely-used platform to do so). This syntax can now be parsed by esbuild and is always passed through untransformed. It's only allowed when the target is `esnext` because the proposal is still in stage 3. It also cannot be used when bundling. Adding support for top-level await to the bundler is complicated since it causes imports to be asynchronous, which has far-reaching implications. This change is mainly for people using esbuild as a library to transform TypeScript into JavaScript one file at a time.\n\n## 0.6.13\n\n* Exclude non-JavaScript files from source maps ([#304](https://github.com/evanw/esbuild/issues/304))\n\n Previously all input files were eligible for source map generation, even binary files included using loaders such as `dataurl`. This was not intentional. Doing this doesn't serve a purpose and can massively bloat the resulting source maps. Now all files are excluded except those loaded by the `js`, `jsx`, `ts`, and `tsx` loaders.\n\n* Fix incorrect source maps with code splitting ([#303](https://github.com/evanw/esbuild/issues/303))\n\n Source maps were completely incorrect when code splitting was enabled for chunk files that imported other chunk files. The source map offsets were not being adjusted past the automatically-generated cross-chunk import statements. This has been fixed.\n\n* Change source map column offsets from bytes to UTF-16 code units\n\n The [source map specification](https://sourcemaps.info/spec.html) leaves many things unspecified including what column numbers mean. Until now esbuild has been generating byte offsets for column numbers, but Mozilla's popular [source-map](https://github.com/mozilla/source-map) library appears to use UTF-16 code unit counts for column numbers instead. With this release, esbuild now also uses UTF-16 code units for column numbers in source maps. This should help esbuild's compatibility with other tools in the ecosystem.\n\n* Fix a bug with partial source mappings\n\n The source map specification makes it valid to have mappings that don't actually map to anything. These mappings were never generated by esbuild but they are sometimes present in source maps generated by other tools. There was a bug where the source map line number would be thrown off if one of these mappings was present at the end of a line. This bug has been fixed.\n\n## 0.6.12\n\n* Fix bugs with cross-chunk assignment handling ([#302](https://github.com/evanw/esbuild/issues/302))\n\n The code splitting process may end up moving the declaration of a file-local variable into a separate chunk from an assignment to that variable. However, it's not possible to assign to a variable in another chunk because assigning to an import is not allowed in ES6. To avoid generating invalid code, esbuild runs an additional pass after code splitting to force all code involved in cross-chunk assignments into the same chunk.\n\n The logic to do this is quite tricky. For example, moving code between chunks may introduce more cross-chunk assignments that also need to be handled. In this case the bug was caused by not handling complex cases with three or more levels of cross-chunk assignment dependency recursion. These cases now have test coverage and should be handled correctly.\n\n## 0.6.11\n\n* Code splitting chunks now use content hashes ([#16](https://github.com/evanw/esbuild/issues/16))\n\n Code that is shared between multiple entry points is separated out into \"chunk\" files when code splitting is enabled. These files are named `chunk.HASH.js` where `HASH` is a string of characters derived from a hash (e.g. `chunk.iJkFSV6U.js`).\n\n Previously the hash was computed from the paths of all entry points which needed that chunk. This was done because it was a simple way to ensure that each chunk was unique, since each chunk represents shared code from a unique set of entry points. But it meant that changing the contents of the chunk did not cause the chunk name to change.\n\n Now the hash is computed from the contents of the chunk file instead. This better aligns esbuild with the behavior of other bundlers. If changing the contents of the file always causes the name to change, you can serve these files with a very large `max-age` so the browser knows to never re-request them from your server if they are already cached.\n\n Note that the names of entry points _do not_ currently contain a hash, so this optimization does not apply to entry points. Do not serve entry point files with a very large `max-age` or the browser may not re-request them even when they are updated. Including a hash in the names of entry point files has not been done in this release because that would be a breaking change. This release is an intermediate step to a state where all output file names contain content hashes.\n\n The reason why this hasn't been done before now is because this change makes chunk generation more complex. Generating the contents of a chunk involves generating import statements for the other chunks which that chunk depends on. However, if chunk names now include a content hash, chunk generation must wait until the dependency chunks have finished. This more complex behavior has now been implemented.\n\n Care was taken to still parallelize as much as possible despite parts of the code having to block. Each input file in a chunk is still printed to a string fully in parallel. Waiting was only introduced in the chunk assembly stage where input file strings are joined together. In practice, this change doesn't appear to have slowed down esbuild by a noticeable amount.\n\n* Fix an off-by-one error with source map generation ([#289](https://github.com/evanw/esbuild/issues/289))\n\n The nested source map support added in version 0.6.5 contained a bug. Input files that were included in the bundle but that didn't themselves contain any generated code caused the source index to shift by one, throwing off the source names of all files after it. This could happen with files consisting only of re-export statements (e.g. `export {name} from 'path'`). This bug has been fixed and this specific scenario now has test coverage.\n\n## 0.6.10\n\n* Revert the binary operator chain change\n\n It turns out this caused some behavior bugs in the generated code.\n\n## 0.6.9\n\n* Performance optimizations for large file transforms\n\n There are two main JavaScript APIs: `build()` which operates on the file system and `transform()` which operates on in-memory data. Previously transforming large files using the JavaScript `transform()` API could be significantly slower than just writing the in-memory string to the file system, calling `build()`, and reading the result back from the file system. This is based on performance tests done on macOS 10.15.\n\n Now esbuild will go through the file system when transforming large files (currently >1mb). This approach is only faster for large files, and can be significantly slower for small files, so small files still keep everything in memory.\n\n* Avoid stack overflow for binary operator chains\n\n Syntax trees with millions of sequential binary operators nested inside each other can cause the parser to stack overflow because it uses a recursive visitor pattern, so each binary operator added an entry to the call stack. Now code like this no longer triggers a stack overflow because the visitor uses the heap instead of the stack in this case. This is unlikely to matter in real-world code but can show up in certain artificial test cases, especially when `--minify-syntax` is enabled.\n\n* Resolve implicitly-named `tsconfig.json` base files ([#279](https://github.com/evanw/esbuild/issues/279))\n\n The official TypeScript compiler lets you specify a package path as the `extends` property of a `tsconfig.json` file. The base file is then searched for in the relevant `node_modules` directory. Previously the package path had to end with the name of the base file. Now you can additionally omit the name of the base file if the file name is `tsconfig.json`. This more closely matches the behavior of the official TypeScript compiler.\n\n* Support for 32-bit Windows systems ([#285](https://github.com/evanw/esbuild/issues/285))\n\n You can now install the esbuild npm package on 32-bit Windows systems.\n\n## 0.6.8\n\n* Attempt to support the taobao.org registry ([#291](https://github.com/evanw/esbuild/issues/291))\n\n This release attempts to add support for the registry at https://registry.npm.taobao.org, which uses a different URL structure than the official npm registry. Also, the install script will now fall back to the official npm registry if installing with the configured custom registry fails.\n\n## 0.6.7\n\n* Custom registry can now have a path ([#286](https://github.com/evanw/esbuild/issues/286))\n\n This adds support for custom registries hosted at a path other than `/`. Previously the registry had to be hosted at the domain level, like npm itself.\n\n* Nested source maps use relative paths ([#289](https://github.com/evanw/esbuild/issues/289))\n\n The original paths in nested source maps are now modified to be relative to the directory containing the source map. This means source maps from packages inside `node_modules` will stay inside `node_modules` in browser developer tools instead of appearing at the root of the virtual file system where they might collide with the original paths of files in other packages.\n\n* Support for 32-bit Linux systems ([#285](https://github.com/evanw/esbuild/issues/285))\n\n You can now install the esbuild npm package on 32-bit Linux systems.\n\n## 0.6.6\n\n* Fix minification bug with `this` values for function calls ([#282](https://github.com/evanw/esbuild/issues/282))\n\n Previously `(0, this.fn)()` was incorrectly minified to `this.fn()`, which changes the value of `this` used for the function call. Now syntax like this is preserved during minification.\n\n* Install script now respects the npm registry setting ([#286](https://github.com/evanw/esbuild/issues/286))\n\n If you have configured npm to use a custom registry using `npm config set registry ` or by installing esbuild using `npm install --registry= ...`, this custom registry URL should now be respected by the esbuild install script.\n\n Specifically, the install script now uses the URL from the `npm_config_registry` environment variable if present instead of the default registry URL `https://registry.npmjs.org/`. Note that the URL must have both a protocol and a host name.\n\n* Fixed ordering between `node_modules` and a force-overridden `tsconfig.json` ([#278](https://github.com/evanw/esbuild/issues/278))\n\n When the `tsconfig.json` settings have been force-overridden using the new `--tsconfig` flag, the path resolution behavior behaved subtly differently than if esbuild naturally discovers the `tsconfig.json` file without the flag. The difference caused package paths present in a `node_modules` directory to incorrectly take precedence over custom path aliases configured in `tsconfig.json`. The ordering has been corrected such that custom path aliases always take place over `node_modules`.\n\n* Add the `--out-extension` flag for custom output extensions ([#281](https://github.com/evanw/esbuild/issues/281))\n\n Previously esbuild could only output files ending in `.js`. Now you can override this to another extension by passing something like `--out-extension:.js=.mjs`. This allows generating output files with the node-specific `.cjs` and `.mjs` extensions without having to use a separate command to rename them afterwards.\n\n## 0.6.5\n\n* Fix IIFE wrapper for ES5\n\n The wrapper for immediately-invoked function expressions is hard-coded to an arrow function and was not updated when the ES5 target was added. This meant that bundling ES5 code would generate a bundle what wasn't ES5-compatible. Doing this now uses a function expression instead.\n\n* Add support for nested source maps ([#211](https://github.com/evanw/esbuild/issues/211))\n\n Source map comments of the form `//# sourceMappingURL=...` inside input files are now respected. This means you can bundle files with source maps and esbuild will generate a source map that maps all the way back to the original files instead of to the intermediate file with the source map.\n\n## 0.6.4\n\n* Allow extending `tsconfig.json` paths inside packages ([#269](https://github.com/evanw/esbuild/issues/269))\n\n Previously the `extends` field in `tsconfig.json` only worked with relative paths (paths starting with `./` or `../`). Now this field can also take a package path, which will be resolved by looking for the package in the `node_modules` directory.\n\n* Install script now avoids the `npm` command ([#274](https://github.com/evanw/esbuild/issues/274))\n\n The install script now downloads the binary directly from npmjs.org instead of using the `npm` command to install the package. This should be more compatible with unusual node environments (e.g. having multiple old copies of npm installed).\n\n* Fix a code splitting bug with re-exported symbols ([#273](https://github.com/evanw/esbuild/issues/273))\n\n Re-exporting a symbol in an entry point didn't correctly track the cross-chunk dependency, which caused the output file to be missing a required import. This bug has been fixed.\n\n* Fix code splitting if a dynamic entry point is doubled as a normal entry point ([#272](https://github.com/evanw/esbuild/issues/272))\n\n Using a dynamic `import()` expression automatically adds the imported path as an entry point. However, manually adding the imported path to the bundler entry point list resulted in a build failure. This case is now handled.\n\n* Fix dynamic imports from a parent directory ([#264](https://github.com/evanw/esbuild/issues/264))\n\n The nested output directory feature interacted badly with the code splitting feature when an entry point contained a dynamic `import()` to a file from a directory that was a parent directory to all entry points. This caused esbuild to generate output paths starting with `../` which stepped outside of the output directory.\n\n The directory structure of the input files is mirrored in the output directory relative to the [lowest common ancestor](https://en.wikipedia.org/wiki/Lowest_common_ancestor) among all entry point paths. However, code splitting introduces a new entry point for each dynamic import. These additional entry points are not in the original entry point list so they were ignored by the lowest common ancestor algorithm. The fix is to make sure all entry points are included, user-specified and dynamic.\n\n## 0.6.3\n\n* Fix `/* @__PURE__ */` IIFEs at start of statement ([#258](https://github.com/evanw/esbuild/issues/258))\n\n The introduction of support for `/* @__PURE__ */` comments in an earlier release introduced a bug where parentheses were no longer inserted if a statement started with a function expression that was immediately invoked. This bug has been fixed and parentheses are now inserted correctly.\n\n* Add support for `@jsx` and `@jsxFrag` comments ([#138](https://github.com/evanw/esbuild/issues/138))\n\n You can now override the JSX factory and fragment values on a per-file basis using comments:\n\n ```jsx\n // @jsx h\n // @jsxFrag Fragment\n import {h, Fragment} from 'preact'\n console.log(<>)\n ```\n\n This now generates the following code:\n\n ```js\n import {h, Fragment} from \"preact\";\n console.log(h(Fragment, null, h(\"a\", null)));\n ```\n\n* Add the `Write` option to the Go API\n\n This brings the Go API to parity with the JavaScript API, and makes certain uses of the `api.Build()` call simpler. You can now specify `Write: true` to have the output files written to the file system during the build instead of having to do that yourself.\n\n## 0.6.2\n\n* Fix code splitting bug with re-export cycles ([#251](https://github.com/evanw/esbuild/issues/251))\n\n Two files that both re-export each other could cause invalid code to be generated when code splitting is enabled. The specific failure was an export statement without a matching import statement from the shared code chunk. This bug has been fixed.\n\n Semantically a `export * from 'path'` statement should behave like a `export {name} from 'path'` statement with the export list determined automatically. And likewise `export {name} from 'path'` should behave like `import {name} from 'path'; export {name}`.\n\n This issue was caused by the re-exported symbols not registering themselves as if they were imported with an import statement. That caused code splitting to fail to generate an import statement when the definition of the symbol ended up in a different chunk than the use of the symbol.\n\n* Fix code splitting bug with missing generated imports\n\n An ES6 module that doesn't import or export anything but that still uses ES6 module syntax (e.g. `import.meta`) interacted badly with some optimizations and caused invalid code to be generated. This generated an import statement without a matching export statement. The bug has been fixed.\n\n To improve tree shaking, esbuild automatically converts `import * as ns from 'path'; use(ns.prop)` into `import {prop} from 'path'; use(prop)` at parse time. The parser doesn't yet know anything about `path` because parsing happens in parallel, so this transformation is always performed.\n\n Later on `path` is determined to be an ES6 module with no exports. This means that there is no symbol to bind `prop` to. Since it was originally a property access on what is now known to be an empty exports object, its value is guaranteed to be undefined. It's no longer a property access so esbuild inlines the undefined value at all uses by replacing `prop` with `void 0`.\n\n However, code splitting wasn't aware of this and still thought imports needed to be generated for uses of `prop`, even though it doesn't actually exist. That caused invalid and unnecessary import statements to be generated. Now code splitting is aware of this undefined substitution behavior and ignores these symbol uses.\n\n## 0.6.1\n\n* Allow bundling with stdin as input ([#212](https://github.com/evanw/esbuild/issues/212))\n\n You can now use `--bundle` without providing any input files and the input will come from stdin instead. Use `--sourcefile=...` to set the name of the input file for error messages and source maps. Dependencies of the input file will be resolved relative to the current working directory.\n\n ```\n # These two commands are now basically equivalent\n esbuild --bundle example.js\n esbuild --bundle < example.js --sourcefile=example.js\n ```\n\n This option has also been added to the JavaScript and Go APIs. If needed, you can customize the resolve directory with the `resolveDir` option:\n\n ```js\n const {outputFiles: [stdout]} = await build({\n stdin: {\n contents: `\n import {version} from './package.json'\n console.log(version as string)\n `,\n sourcefile: 'example.ts',\n resolveDir: __dirname,\n loader: 'ts',\n },\n bundle: true,\n write: false,\n })\n console.log(stdout)\n ```\n\n* Implement `extends` for `tsconfig.json` ([#233](https://github.com/evanw/esbuild/issues/233))\n\n A `tsconfig.json` file can inherit configurations from another file using the `extends` property. Before this release, esbuild didn't support this property and any inherited settings were missing. Now esbuild should include these inherited settings.\n\n* Allow manually overriding `tsconfig.json` ([#226](https://github.com/evanw/esbuild/issues/226))\n\n Normally esbuild finds the appropriate `tsconfig.json` file by walking up the directory tree. This release adds the `--tsconfig=...` flag which lets you disable this feature and force esbuild to use the provided configuration file instead. This corresponds to the TypeScript compiler's `--project` flag.\n\n* Remove gaps in source maps within a file ([#249](https://github.com/evanw/esbuild/issues/249))\n\n The widely-used [source-map](https://github.com/mozilla/source-map) library for parsing source maps [has a bug](https://github.com/mozilla/source-map/issues/261) where it doesn't return mappings from previous lines. This can cause queries within generated code to fail even though there are valid mappings on both sides of the query.\n\n To work around this issue with the source-map library, esbuild now generates a mapping for every line of code that is generated from an input file. This means that queries with the source-map library should be more robust. For example, you should now be able to query within a multi-line template literal and not have the query fail.\n\n Note that some lines of code generated during bundling will still not have source mappings. Examples include run-time library code and cross-chunk imports and exports.\n\n## 0.6.0\n\n* Output directory may now contain nested directories ([#224](https://github.com/evanw/esbuild/issues/224))\n\n Note: This is a breaking change if you use multiple entry points from different directories. Output paths may change with this upgrade.\n\n Previously esbuild would fail to bundle multiple entry points with the same name because all output files were written to the same directory. This can happen if your entry points are in different nested directories like this:\n\n ```\n src/\n ├─ a/\n │ └─ page.js\n └─ b/\n └─ page.js\n ```\n\n With this release, esbuild will now generate nested directories in the output directory that mirror the directory structure of the original entry points. This avoids collisions because the output files will now be in separate directories. The directory structure is mirrored relative to the [lowest common ancestor](https://en.wikipedia.org/wiki/Lowest_common_ancestor) among all entry point paths. This is the same behavior as [Parcel](https://github.com/parcel-bundler/parcel) and the TypeScript compiler.\n\n* Silence errors about missing dependencies inside try/catch blocks ([#247](https://github.com/evanw/esbuild/issues/247))\n\n This release makes it easier to use esbuild with libraries such as [debug](npmjs.com/package/debug) which contain a use of `require()` inside a `try`/`catch` statement for a module that isn't listed in its dependencies. Normally you need to mark the library as `--external` to silence this error. However, calling `require()` and catching errors is a common pattern for conditionally importing an unknown module, so now esbuild automatically treats the missing module as external in these cases.\n\n* TypeScript type definitions for the browser API\n\n The node-based JavaScript API already ships with TypeScript type checking for the `esbuild` and `esbuild-wasm` packages. However, up until now the browser-based JavaScript API located in `esbuild-wasm/lib/browser` did not have type definitions. This release adds type definitions so you can now import `esbuild-wasm/lib/browser` in TypeScript and get type checking.\n\n* Add chunk imports to metadata file ([#225](https://github.com/evanw/esbuild/issues/225))\n\n With code splitting, it's sometimes useful to list out the chunks that will be needed by a given entry point. For example, you may want to use that list to insert one `` tag for each chunk in your page header. This information is now present in the JSON metadata file that's generated with the `--metafile` flag. Each object in the `outputs` map now has an `imports` array, and each import has a `path`.\n\n## 0.5.26\n\n* Allow disabling non-existent modules with the `browser` package.json field ([#238](https://github.com/evanw/esbuild/issues/238))\n\n The [browser field](https://github.com/defunctzombie/package-browser-field-spec) in package.json allows you to disable a module (i.e. force it to become empty) by adding an override that points to `false`. Previously esbuild still required it to have an existing absolute path on the file system so that the disabled module could have a consistent identity. Now this is no longer required, so you can disable modules that don't exist on the file system. For example, you can now use this feature to disable the `fs` module.\n\n* Fix a bug with syntax transformation and `super()` calls ([#242](https://github.com/evanw/esbuild/issues/242))\n\n In certain situations, esbuild accidentally transformed a class constructor such that a call to `super()` that came first in the original code no longer came first in the generated code. This code generation bug has now been fixed. Calls to `super()` that come first are should now stay that way.\n\n## 0.5.25\n\n* Performance improvment for repeated API calls\n\n Previously every build or transform API call required parsing a new copy of the [esbuild JavaScript runtime code](internal/runtime/runtime.go). This added a constant overhead for every operation. Now the parsing of the runtime code is cached across API calls. The effect on performance depends on the size of the files you're transforming. Transform API calls appear to be >2x faster for small files, around ~10% faster for normal-sized files, and insignificant for large files.\n\n* Add a binary loader\n\n You can now assign the `binary` loader to a file extension to load all files of that type into a Uint8Array. The data is encoded as a base64 string and decoded into a Uint8Array at run time. The decoder defaults to a custom platform-independent implementation (faster than `atob`) but it switches to using the `Buffer` API with `--platform=node`.\n\n* Add fine-grained `--target` environments ([#231](https://github.com/evanw/esbuild/issues/231))\n\n You can now configure individual JavaScript environments as targets. The `--target` flag now takes a comma-separated list of values like this: `--target=chrome58,firefox57,safari11,edge16`. Compatibility data was mainly sourced from [this widely-used compatibility table](https://kangax.github.io/compat-table/es2016plus/).\n\n There is also now an additional `es5` target. Since no transforms to ES5 are implemented yet, its purpose is mainly to prevent ES6 syntax from accidentally being compiled. This target also prevents esbuild from doing some ES6-specific optimizations that would unintentionally change ES5 code into ES6 code.\n\n## 0.5.24\n\n* Smaller code for loaders that generate expressions\n\n Loaders that generate expressions (`json`, `text`, `base64`, `file`, and `dataurl`) export them using an assignment to `module.exports`. However, that forces the creation of a CommonJS module which adds unnecessary extra code. Now if the file for that loader is only imported using ES6 import statements instead of `require()`, the expression is exported using an `export default` statement instead. This generates smaller code. The bundler still falls back to the old `module.exports` behavior if the file is imported using `require()` instead of an ES6 import statement.\n\n Example input file:\n\n ```js\n import txt from './example.txt'\n console.log(txt)\n ```\n\n Old bundling behavior:\n\n ```js\n // ...code for __commonJS() and __toModule() omitted...\n\n // example.txt\n var require_example = __commonJS((exports, module) => {\n module.exports = \"This is a text file.\";\n });\n\n // example.ts\n const example = __toModule(require_example());\n console.log(example.default);\n ```\n\n New bundling behavior:\n\n ```js\n // example.txt\n var example_default = \"This is a text file.\";\n\n // example.ts\n console.log(example_default);\n ```\n\n In addition, top-level properties of imported JSON files are now converted into individual ES6 exports for better tree shaking. For example, that means you can now import the `version` property from your `package.json` file and the entire JSON file will be removed from the bundle:\n\n ```js\n import {version} from './package.json'\n console.log(version)\n ```\n\n The example above will now generate code that looks like this:\n\n ```js\n // package.json\n var version = \"1.0.0\";\n\n // example.ts\n console.log(version);\n ```\n\n## 0.5.23\n\n* Fix `export declare` inside `namespace` in TypeScript ([#227](https://github.com/evanw/esbuild/issues/227))\n\n The TypeScript parser assumed that ambient declarations (the `declare` keyword) just declared types and did not affect the output. This was an incorrect assumption for exported declarations of local variables inside namespaces. The assignment to `foo` in the example below must be rewritten to an assignment to `ns.foo`:\n\n ```ts\n namespace ns {\n export declare let foo: number\n foo = 123\n }\n ```\n\n This should now work correctly.\n\n* Preserve certain statement-level comments ([#221](https://github.com/evanw/esbuild/issues/221))\n\n Statement-level comments starting with `//!` or `/*!` or containing `@preserve` or `@license` are now preserved in the output. This matches the behavior of other JavaScript tools such as [Terser](https://github.com/terser/terser).\n\n* Higher memory limit for synchronous JavaScript APIs ([#228](https://github.com/evanw/esbuild/issues/228))\n\n Apparently the synchronous APIs in node's child process module that esbuild relies on will fail with `ENOBUFS` if the output is larger than a certain size. This caused issues with the `write: false` feature from the previous release. The memory limit has been raised to 16mb which should hopefully avoid these crashes. If that limit is still too low, it can be overridden with the `ESBUILD_MAX_BUFFER` environment variable.\n\n## 0.5.22\n\n* JavaScript build API can now avoid writing to the file system ([#139](https://github.com/evanw/esbuild/issues/139) and [#220](https://github.com/evanw/esbuild/issues/220))\n\n You can now pass `write: false` to the JavaScript build API to avoid writing to the file system. Instead, the returned object will have the `outputFiles` property with an array of output files, each of which has a string `path` property and a Uint8Array `contents` property. This brings the JavaScript API to parity with the Go API, which already had this feature.\n\n* Support `/* @__PURE__ */` annotations for tree shaking\n\n You can now annotate call expressions and new expressions with a `/* @__PURE__ */` comment, which tells esbuild that the function call is allowed to be removed if the result is not used. This is a convention from other tools (e.g. UglifyJS and Rollup).\n\n For example, the code below will now be completely removed during bundling if the `fib` variable is never used. The initializer is a function call and esbuild cannot determine that it has no side effects, but the annotation forces esbuild to consider it removable anyway:\n\n ```js\n let fib = /* @__PURE__ */ (() => {\n let cache = {}\n return function f(n) {\n return cache[n] || (cache[n] =\n n <= 2 ? 1 : f(n - 1) + f(n - 2));\n }\n })()\n ```\n\n* Add `--pure:name` to annotate calls to globals ([#28](https://github.com/evanw/esbuild/issues/28))\n\n This flag makes calls to the named function behave as if that call was prefixed by `/* @__PURE__ */`. For example, `--pure:console.log` means calls to `console.log()` will behave as if they were calls to `/* @__PURE__ */ console.log()` instead. This means when `--minify` is active, the calls will be removed as long as the return value is unused (any function arguments with side effects will be kept, however).\n\n* Add basic tree shaking of JSX elements\n\n Automatically-generated calls to the JSX factory function (usually `React.createElement`) are now marked as `/* @__PURE__ */`. This means the construction of a JSX element is now not considered to have side effects. For example, the code below will be completely removed during bundling if the `element` variable is never used:\n\n ```jsx\n let element =
an unused element
\n ```\n\n* Fixed a concurrency issue with the JavaScript API\n\n Before this release, multiple concurrent JavaScript API calls that used different values for the `define` option could end up using the value from another API call. This bug was due to inverted boolean logic in code that was intended to cache the define map only when there were no user-specified defines. The issue has been fixed.\n\n## 0.5.21\n\n* Binaries for FreeBSD ([#217](https://github.com/evanw/esbuild/pull/217))\n\n There are now esbuild binaries for FreeBSD, both for AMD64 and ARM64. This was contributed by [@kikuchan](https://github.com/kikuchan).\n\n* Remove nested `node_modules` directory\n\n The install script for the `esbuild` npm package invokes `npm` recursively to install the binary for the current platform. However, the left over nested `node_modules` directory could potentially cause problems with tools that scan for nested `node_modules` directories. Now the install script no longer leaves a nested `node_modules` directory around after finishing.\n\n## 0.5.20\n\n* Allow multiple `.` characters in loader extensions ([#215](https://github.com/evanw/esbuild/issues/215))\n\n You are now able to configure two loaders such that one is the suffix of the other. For example, you can now configure both `--loader:.txt=text` and `--loader:.base64.txt=base64`. The loader with the longer matching suffix will be used.\n\n* Add support for scoped external packages ([#214](https://github.com/evanw/esbuild/issues/214))\n\n You can now mark scoped packages as external. For example, `--external:@babel/core` marks the package `@babel/core` as external. This was contributed by [@floydspace](https://github.com/floydspace).\n\n* Add support for external paths ([#127](https://github.com/evanw/esbuild/issues/127) and [#191](https://github.com/evanw/esbuild/issues/191))\n\n Previously the `--external:M` flag only worked if `M` was a package name. For example, you can mark the `fs` package as external with `--external:fs`.\n\n With this release, you can now also mark file paths as external using the same syntax. For example, `--external:./index.js` marks the file `index.js` in the current working directory as external. The path to the external module used in the output file will be relative to the output directory.\n\n## 0.5.19\n\n* Fix bug with TypeScript `typeof` operator ([#213](https://github.com/evanw/esbuild/issues/213))\n\n The TypeScript parser in esbuild incorrectly treated `readonly` in `typeof readonly` as a type operator instead of an identifier, which meant that it expected a type expression to follow the `readonly` identifier. Type expressions containing `typeof readonly` are now parsed correctly.\n\n## 0.5.18\n\n* Fix bug with code splitting and side effects\n\n This release fixes a bug with experimental code splitting. Chunks with side effects but without any exports were not imported by the entry points that depended on them, which meant that their side effects accidentally did not occur. The fix ensures that all entry points import all relevant chunks regardless of whether or not the chunks have exports, so their side effects should never be omitted.\n\n## 0.5.17\n\n* Pass through `import.meta` syntax ([#208](https://github.com/evanw/esbuild/issues/208))\n\n The `import.meta` syntax is a way for code in an ES6 module to access metadata about itself. For example, `import.meta.url` in the browser is the URL of the current module.\n\n It's a new feature that doesn't work in older browsers, so esbuild converts it to a module-local variable to avoid generating code with a syntax error. However, this is only necessary when targeting older browsers or if the output format doesn't support `import.meta`.\n\n The `import.meta` syntax is now passed through unmodified when the target is `es2020` or newer and the output format is `esm`. This lets you use features such as `import.meta.url` in those situations.\n\n## 0.5.16\n\n* Experimental code splitting with `--splitting` ([#16](https://github.com/evanw/esbuild/issues/16))\n\n This release includes experimental support for code splitting. Enable it with the `--splitting` flag. This currently only works with the `esm` output format. Support for the `cjs` and `iife` formats will come later. It's being released early so people can try it out and provide feedback.\n\n When enabled, code splitting does two things:\n\n * An asynchronous `import('path')` expression will create another chunk that will only be loaded when that expression is evaluated. This is intended to be used for lazily loading additional code. All additional chunks will be written to the directory configured with `outdir`.\n\n Note that when code splitting is disabled (i.e. the default behavior), an `import('path')` expression behaves similar to `Promise.resolve(require('path'))` and still bundles the imported file into the entry point bundle. No additional chunks are generated in this case.\n\n * Multiple entry points will cause additional chunks to be created for code that is shared between entry points. Chunks are generated automatically based on simple principles: code should only ever be in one chunk (i.e. no duplication) and no unnecessary code should be loaded (i.e. chunk boundaries are minimal).\n\n The way this works is by traversing through the module dependency graph and marking which top-level statements are reachable from which entry points. The set of entry points for a given top-level statement determines which chunk that statement is in.\n\n This is an advanced form of code splitting where even a single file may end up being split into different chunks. This is not something most other bundlers can do at the moment.\n\n Note that using code splitting with many entry points may generate many chunks for shared code reachable from different combinations of entry points. This should work fine and should still be efficient with HTTP/2. If you want to only let certain entry points share code, you can run esbuild multiple times for different groups of entry points.\n\n Please try it out and report any issues on [#16](https://github.com/evanw/esbuild/issues/16).\n\n## 0.5.15\n\n* Remove some unnecessary helper functions ([#206](https://github.com/evanw/esbuild/issues/206))\n\n Certain unnecessary helper functions were sometimes generated when the output format was `esm`. These helper functions should now only be generated when necessary.\n\n* Optimize CommonJS-to-ES6 module conversion\n\n CommonJS modules that exported raw strings were unnecessarily slow when imported using an ES6 import statement. This scenario should now be much faster.\n\n The CommonJS-to-ES6 module conversion in esbuild copies properties off the object one-by-one onto a new object. This is the same approach that the TypeScript compiler uses. However, strings have numeric properties 0 to N-1 where N is the length of the string. Copying all of these numeric properties can take a significantly long time for long strings and is almost certainly unhelpful. Now esbuild's CommonJS-to-ES6 module conversion only copies properties if the export is an object.\n\n* Support JSX fields in `tsconfig.json`\n\n This release adds support for the `jsxFactory` and `jsxFragmentFactory` fields in `tsconfig.json`. Now you do not have to configure JSX again for esbuild if you have already configured it for TypeScript. The `jsxFragmentFactory` field is a [new feature in the upcoming TypeScript 4.0 release](https://devblogs.microsoft.com/typescript/announcing-typescript-4-0-beta/#custom-jsx-factories).\n\n## 0.5.14\n\n* Prevent assignment to ES6 imports ([#202](https://github.com/evanw/esbuild/issues/202))\n\n ES6 imports are live bindings to other values, sort of like a getter-only property on an object. An assignment to an import identifier should cause a `TypeError` at run time according to the specification. However, when bundling esbuild performs the \"scope hoisting\" optimization and merges all modules into a single scope. Imports inside the bundle refer to the imported identifiers without any indirection and an assignment will not throw a `TypeError` at run time.\n\n This release turns assignments to imports into compile-time errors to reject invalid code instead of allowing it to cause this non-conforming behavior. Handling this at compile-time is consistent with other tools such as TypeScript and Rollup.\n\n* Exclude external child paths from the bundle ([#186](https://github.com/evanw/esbuild/pull/186))\n\n Marking a module as external via `--external:foo` means any imports for the module `foo` will be preserved in the output instead of being traversed by the bundler. This is helpful if the module contains problematic code such as a native node module that can't be bundled.\n\n However, code often uses child paths to import a file within a module directly such as `import \"foo/bar\"`. These paths accidentally bypassed the external module check. The fix means all paths under an external module are now also considered external. This was contributed by [@floydspace](https://github.com/floydspace).\n\n## 0.5.13\n\n* Add support for TypeScript labelled tuples\n\n This is a new TypeScript feature to be released in TypeScript 4. Tuple types can now have labels:\n\n ```ts\n let foo: [number, number] // Without labels\n let bar: [min: number, max: number] // With labels\n ```\n\n These labels are ignored by the TypeScript compiler and are only there to improve readability. You can read more here: https://devblogs.microsoft.com/typescript/announcing-typescript-4-0-beta/.\n\n## 0.5.12\n\n* Fix a JSX whitespace bug ([#195](https://github.com/evanw/esbuild/issues/195))\n\n Whitespace behavior in JSX has unfortunately been [left out of the JSX specification](https://github.com/facebook/jsx/issues/6), so it's up to each implementation to determine how to handle whitespace characters. Most of the JSX parsers in the ecosystem have converged on similar behavior. When they differ, esbuild follows the behavior of the TypeScript JSX parser.\n\n This release fixes a bug where esbuild's JSX parser behaved differently than TypeScript. Certain whitespace characters between JSX elements were incorrectly removed. For example, the space in ` ` must be preserved to match the TypeScript JSX parser. These cases now have test coverage.\n\n## 0.5.11\n\n* Fix a JavaScript API crash on node 10.x\n\n The current LTS version of node is 12.x, but some people are still running 10.x and want to use esbuild. Before this fix, attempting to use the esbuild JavaScript API with node 10.x would crash with `ReferenceError: TextEncoder is not defined`. The JavaScript API has been changed to not require `TextEncoder` and now works fine with node 10.x.\n\n## 0.5.10\n\n* Transform object rest properties\n\n This release transforms object rest property bindings such as `let {...x} = y` when the language target is set to `--target=es2017` or earlier.\n\n If you're using Babel to transform your source code to ES6 for older browsers, this probably means esbuild's JavaScript API could now be a suitable replacement for Babel in your case. The only remaining features that esbuild can't yet transform to ES6 are a few very rarely used features that don't matter for the vast majority of real-world code (`for async` loops and `async` generators).\n\n## 0.5.9\n\n* Add the `--strict:nullish-coalescing` option\n\n This affects the transform for the `??` nullish coalescing operator. In loose mode (the default), `a ?? b` is transformed to `a != null ? a : b`. This works fine in all cases except when `a` is the special object `document.all`. In strict mode, `a ?? b` is transformed to `a !== null && a !== void 0 ? a : b` which works correctly with `document.all`. Enable `--strict:nullish-coalescing` if you need to use `document.all` with the `??` operator.\n\n* Add the `--strict:class-fields` option\n\n This affects the transform for instance and static class fields. In loose mode (the default), class field initialization is transformed to a normal assignment. This is what the TypeScript compiler does by default. However, it doesn't follow the JavaScript specification exactly (e.g. it may call setter methods). Either enable `--strict:class-fields` or add `useDefineForClassFields` to your `tsconfig.json` file if you need accurate class field initialization.\n\nNote that you can also just use `--strict` to enable strictness for all transforms instead of using `--strict:...` for each transform.\n\n## 0.5.8\n\n* Transform async functions ([#137](https://github.com/evanw/esbuild/issues/137))\n\n This release transforms async functions into generator functions for older browsers when the language target is set to `--target=es2016` or below. The transform esbuild uses is similar to the one used by the TypeScript compiler.\n\n## 0.5.7\n\n* Transform private fields and private methods ([#47](https://github.com/evanw/esbuild/issues/47))\n\n Private names are an access control mechanism for classes. They begin with a `#` and are not accessible outside of the class they are declared in. Support for parsing this syntax was added in esbuild version 0.4.9 but the syntax was passed through unmodified, meaning it didn't work in older browsers.\n\n This release adds support for transforming private fields and private methods for older browsers that don't support this syntax. This transform uses `WeakMap` and `WeakSet` to preserve the privacy properties of this feature, similar to the corresponding transforms in the Babel and TypeScript compilers.\n\n This code:\n\n ```js\n class Counter {\n #count = 1\n get value() { return this.#count }\n increment() { ++this.#count }\n }\n ```\n\n is transformed into this code when using `--target=es2020`:\n\n ```js\n var _count;\n class Counter {\n constructor() { _count.set(this, 1); }\n get value() { return __privateGet(this, _count); }\n increment() { __privateSet(this, _count, +__privateGet(this, _count) + 1); }\n }\n _count = new WeakMap();\n ```\n\n Note that most modern JavaScript engines (V8, JavaScriptCore, and SpiderMonkey but not ChakraCore) may not have good performance characteristics for large `WeakMap` and `WeakSet` objects. Creating many instances of classes with private fields or private methods with this syntax transform active may cause a lot of overhead for the garbage collector. This is because modern engines (other than ChakraCore) store weak values in an actual map object instead of as hidden properties on the keys themselves, and large map objects can cause performance issues with garbage collection. See [this reference](https://github.com/tc39/ecma262/issues/1657#issuecomment-518916579) for more information.\n\n* Fix re-exports when bundling\n\n This is similar to the fix for re-exports in version 0.5.6 except that it applies when bundling, instead of just when transforming. It needed to be fixed differently because of how cross-file linking works when bundling.\n\n## 0.5.6\n\n* Fix re-export statements ([#190](https://github.com/evanw/esbuild/issues/190))\n\n The previous release caused a regression due to some behind-the-scenes work for the upcoming code splitting feature. The re-export alias in statements of the form `export { foo as bar } from 'path'` could sometimes incorrectly be renamed to something else, such as `foo` becoming `foo2`. This release fixes the bug.\n\n## 0.5.5\n\n* Implement logical assignment operator transforms\n\n There are three new logical assignment operators: `??=`, `&&=`, and `||=`. With this release, you can now use them in older browsers by setting `--target` to a language version other than `esnext`. See [the V8 blog post](https://v8.dev/features/logical-assignment) for more information about how they work.\n\n* Fix re-exports of a CommonJS module in `esm` format\n\n Previously re-exports of an individual identifier from a CommonJS module generated JavaScript that crashed at run-time when using the `esm` output format. This was because esbuild always tries to generate \"live\" exports for CommonJS modules that always return the current value of the export instead of \"dead\" bindings that only return the initial value of the export. The bug happened because the ES6 module format doesn't have a way to forward a live binding to a CommonJS module as an ES6 export. The fix is to generate \"dead\" exports instead, which is the only available option in this edge case.\n\n These input files:\n\n ```js\n // entry_point.js\n export {foo} from './cjs-format.js'\n ```\n\n ```js\n // cjs-format.js\n Object.defineProperty(exports, 'foo', {\n enumerable: true,\n get: () => Math.random(),\n })\n ```\n\n Now become this output file:\n\n ```js\n // cjs-format.js\n var require_cjs_format = __commonJS((exports) => {\n Object.defineProperty(exports, \"foo\", {\n enumerable: true,\n get: () => Math.random()\n });\n });\n\n // entry_point.js\n const cjs_format = __toModule(require_cjs_format());\n const export_foo = cjs_format.foo; // This is a \"dead\" re-export\n export {\n export_foo as foo\n };\n ```\n\n## 0.5.4\n\n* Source maps use `/` on Windows ([#188](https://github.com/evanw/esbuild/issues/188))\n\n Before generated source maps used `\\` on Windows, which meant that tools consuming these source maps (e.g. Chrome) didn't recognize these characters as path separators. Now all platforms consistently use `/` as a path separator.\n\n* Prevent input files from being overwritten\n\n There are now checks in place to avoid input files being accidentally overwritten. This could easily happen with `--bundle --outdir=.` when bundling JavaScript files since the output file name ends up being the same as the entry point name, and is written to the same directory.\n\n## 0.5.3\n\n* Special-case `require` in browserify bundles ([#80](https://github.com/evanw/esbuild/issues/80) and [#90](https://github.com/evanw/esbuild/issues/90))\n\n [Browserify](https://browserify.org/) generates code containing the expression `typeof require == \"function\" && require` which then ends up in a lot of npm packages. This expression is problematic because bundling involves statically determining all source files and their dependencies. Using `require` dynamically like this defeats the static analysis. It's also problematic because esbuild replaces `typeof require == \"function\"` with `true` since `require` is a function at compile-time when bundling. Then `true && require` becomes `require` in the generated code, which crashes at run time.\n\n Previously esbuild would generate an error for these expressions. Now esbuild replaces `typeof require == \"function\" && require` with `false` when targeting the browser and `require` when targeting node. This matches the intent of the browserify prelude snippet and allows esbuild to build libraries containing this code without errors or warnings.\n\n* Allow dynamic dependencies ([#113](https://github.com/evanw/esbuild/issues/113))\n\n Bundling `require()` or `import()` when the argument isn't a string literal is a dynamic dependency. The dependency path relies on dynamic run-time behavior and cannot be statically determined by esbuild at bundle time.\n\n Dynamic dependencies used to be an error but are now just a warning. Builds containing them now succeed and the generated code contains the `require()` or `import()` expression. This is useful either when the dynamic dependency is intentional or when you know the dynamic dependency won't ever be triggered. Doing this still generates a warning to alert you that some code was excluded from the bundle and because these expressions may still crash at run time if the imported path isn't valid.\n\n## 0.5.2\n\n* Fix a regression with `--define` and identifiers\n\n The API refactor introduced a regression where using a `--define` flag to replace something with an identifier followed by another `--define` flag unintentionally caused the first `--define` to use the value from the second `--define` for replacement. This regression was caused by a loop that was added around a Go closure, which caused all closures in that loop to close over the same variable. The bug has been fixed.\n\n* Fix interpretation of legacy `-->` single-line HTML comments\n\n The `-->` sequence starts a single-line comment similar to `//`. This is legacy behavior from [annex B](https://www.ecma-international.org/ecma-262/6.0/#sec-html-like-comments) under the name `SingleLineHTMLCloseComment`. However, `-->` was incorrectly treated as the start of a comment even when it didn't come at the beginning of the line. Now `-->` only starts a comment if there are no tokens before it on that line.\n\n* Allow shadowing of CommonJS variables ([#165](https://github.com/evanw/esbuild/issues/165))\n\n It's now no longer an error to re-declare `exports`, `module`, or `require` in a module scope. The re-declared symbol will just silently shadow the CommonJS variable with that name. This allows to use a variable called `exports` in an ES6 module, for example.\n\n## 0.5.1\n\n* Go documentation was moved to godoc ([#177](https://github.com/evanw/esbuild/pull/177))\n\n The Go documentation is now in the source files itself instead of in an external Markdown file. View it online at https://godoc.org/github.com/evanw/esbuild/pkg/api and https://godoc.org/github.com/evanw/esbuild/pkg/cli.\n\n* The browser API now works in a script tag\n\n The initial release of the browser API required a bundler to use correctly since it was in CommonJS format. This release adds the ability to use the browser API directly in HTML.\n\n Here's an example using https://unpkg.com/ for simplicity, although you should consider hosting the files yourself:\n\n ```html\n \n \n ```\n\n## 0.5.0\n\n* Overhaul public-facing API code\n\n This is a rewrite of all externally facing API code. It fixes some bugs and inconsistencies, adds some new features, and makes it easier to support various use cases going forward.\n\n At a high-level, esbuild's API supports two separate operations: \"build\" and \"transform\". Building means reading from the file system and writing back to the file system. Transforming takes an input string and generates an output string. You should use the build API if you want to take advantage of esbuild's bundling capability, and you should use the transform API if you want to integrate esbuild as a library inside another tool (e.g. a \"minify\" plugin). This rewrite ensures the APIs for these two operations are exposed consistently for all ways of interacting with esbuild (both through the CLI and as a library).\n\n Here are some of the highlights:\n\n * There is now a public Go API ([#152](https://github.com/evanw/esbuild/issues/152))\n\n The main API can be found in the [`github.com/evanw/esbuild/pkg/api`](pkg/api/api.go) module. It exposes the exact same features as the JavaScript API. This means you can use esbuild as a JavaScript transformation and bundling library from Go code without having to run esbuild as a child process. There is also the [`github.com/evanw/esbuild/pkg/cli`](pkg/cli/cli.go) module which can be used to wrap the esbuild CLI itself.\n\n * There are now synchronous JavaScript APIs ([#136](https://github.com/evanw/esbuild/issues/136))\n\n Sometimes JavaScript source transformations must be synchronous. For example, using esbuild's API to shim `require()` for `.ts` files was previously not possible because esbuild only had an asynchronous transform API.\n\n This release adds the new `transformSync()` and `buildSync()` synchronous functions to mirror the existing `transform()` and `build()` asynchronous functions. Note that these synchronous calls incur the cost of starting up a new child process each time, so you should only use these instead of `startService()` if you have to (or if you don't care about optimal performance).\n\n * There is now an experimental browser-based API ([#172](https://github.com/evanw/esbuild/issues/172))\n\n The `esbuild-wasm` package now has a file called `browser.js` that exposes a `startService()` API which is similar to the esbuild API available in node. You can either import the `esbuild-wasm` package using a bundler that respects the `browser` field in `package.json` or import the `esbuild-wasm/lib/browser.js` file directly.\n\n This is what esbuild's browser API looks like:\n\n ```ts\n interface BrowserOptions {\n wasmURL: string\n worker?: boolean\n }\n\n interface BrowserService {\n transform(input: string, options: TransformOptions): Promise\n stop(): void\n }\n\n declare function startService(options: BrowserOptions): Promise\n ```\n\n You must provide the URL to the `esbuild-wasm/esbuild.wasm` file in `wasmURL`. The optional `worker` parameter can be set to `false` to load the WebAssembly module in the same thread instead of creating a worker thread. Using a worker thread is recommended because it means transforming will not block the main thread.\n\n This API is experimental and may be changed in the future depending on the feedback it gets.\n\n * Error messages now use `sourcefile` ([#131](https://github.com/evanw/esbuild/issues/131))\n\n Errors from transform API calls now use `sourcefile` as the original file name if present. Previously the file name in error messages was always `/input.js`.\n\n## 0.4.14\n\n* Do not reorder `\"use strict\"` after support code ([#173](https://github.com/evanw/esbuild/issues/173))\n\n Even when not in bundling mode, esbuild sometimes adds automatically-generated support code at the start of the output file. For example, using the `**` operator with `--target=es2015` causes `let __pow = Math.pow` to be inserted at the start of the file. This interfered with `\"use strict\"` directives, which must come first. Now `\"use strict\"` directives are written out first before any automatically-generated support code.\n\n* Fix bug with export star pointing to a re-export ([#176](https://github.com/evanw/esbuild/issues/176))\n\n This fixes a tree shaking bug that involves an `export * from ...` statement pointing to a file with a `export {name} from ...` statement. Now `name` will no longer be incorrectly removed from the bundle.\n\n## 0.4.13\n\n* Fix possible name collision with CommonJS the target ([#174](https://github.com/evanw/esbuild/issues/174))\n\n A bug meant that the export objects for individual modules with the same filename could in some cases end up reusing the same name in the output file, which then caused a syntax error. This only happened with the `cjs` target. The bug has been fixed.\n\n## 0.4.12\n\n* Support `export * from ...` for CommonJS modules ([#159](https://github.com/evanw/esbuild/issues/159))\n\n Wildcard re-exports are now supported when the exports come from a CommonJS or external module. Since CommonJS modules are not statically analyzable, this means in these cases the re-exports are evaluated at run time instead of at bundle time. Modules that re-export symbols this way will also be considered CommonJS modules during bundling because their exports are now also not statically analyzable.\n\n* Add 3rd-party library test coverage\n\n From the esbuild repo, you can now run `make test-extra` to build some 3rd-party libraries (Rollup, Sucrase, and Esprima) with esbuild and run their test suites. This ensures that these libraries will continue to work as esbuild releases new features.\n\n## 0.4.11\n\n* Fix top-level name minification with runtime\n\n When not bundling, esbuild only minifies top-level names if the file is an ES6 module (as determined by the presence of an ES6 import or export statement). This determination had a bug where a non-module file was considered a module if esbuild automatically generated an import to some internal support code called the \"runtime\". For example, using the `**` operator with `--target=es2015` generates an import for the `__pow` runtime function. Runtime imports are now ignored for module determination, so an automatically-generated runtime import no longer causes top-level names to be minified.\n\n* Fix class name generation for default exports\n\n Some changes to name generation for TypeScript decorators caused the generated class name for `export default class` statements to sometimes not match the name used for other references to that class in the same file. This bug has been fixed.\n\n## 0.4.10\n\n* Initial implementation of TypeScript decorators ([#104](https://github.com/evanw/esbuild/issues/104))\n\n This release contains an initial implementation of the non-standard TypeScript-specific decorator syntax. This syntax transformation is enabled by default in esbuild, so no extra configuration is needed. The TypeScript compiler will need `\"experimentalDecorators\": true` configured in `tsconfig.json` for type checking to work with TypeScript decorators.\n\n Here's an example of a method decorator:\n\n ```ts\n function logged(target, key, descriptor) {\n let method = descriptor.value\n descriptor.value = function(...args) {\n let result = method.apply(this, args)\n let joined = args.map(x => JSON.stringify(x)).join(', ')\n console.log(`${key}(${joined}) => ${JSON.stringify(result)}`)\n return result\n }\n }\n\n class Example {\n @logged\n method(text: string) {\n return text + '!'\n }\n }\n\n const x = new Example\n x.method('text')\n ```\n\n There are four kinds of TypeScript decorators: class, method, parameter, and field decorators. See [the TypeScript decorator documentation](https://www.typescriptlang.org/docs/handbook/decorators.html) for more information. Note that esbuild only implements TypeScript's `experimentalDecorators` setting. It does not implement the `emitDecoratorMetadata` setting because that requires type information.\n\n* Fix order of side effects for computed fields\n\n When transforming computed class fields, esbuild had a bug where the side effects of the field property names were not evaluated in source code order. The order of side effects now matches the order in the source code.\n\n* Fix private fields in TypeScript\n\n This fixes a bug with private instance fields in TypeScript where the private field declaration was incorrectly removed during the TypeScript class field transform, which inlines the initializers into the constructor. Now the initializers are still moved to the constructor but the private field declaration is preserved without the initializer.\n\n Note that since static private fields are not currently supported by the official TypeScript compiler, they are also not supported by esbuild in TypeScript files. They are supported by esbuild in JavaScript files, however.\n\n## 0.4.9\n\n* Initial support for private names ([#47](https://github.com/evanw/esbuild/issues/47))\n\n Private names are an access control mechanism for classes. They begin with a `#` and are not accessible outside of the class they are declared in. The private name syntax can now be parsed, printed, and minified correctly. Transforming this syntax for older browsers is not supported yet. This is what the syntax looks like:\n\n ```js\n class Counter {\n #count = 1\n get value() { return this.#count }\n increment() { this.#count++ }\n }\n ```\n\n You can read more about these features here:\n\n * https://github.com/tc39/proposal-private-methods\n * https://github.com/tc39/proposal-class-fields\n * https://github.com/tc39/proposal-static-class-features\n\n* Initial support for logical assignment operators\n\n This adds support for the three new logical assignment operators `||=`, `&&=`, and `??=`, which can now be parsed and passed through to the output. Transforming this syntax for older browsers is not supported yet. You can read more about these operators here: https://github.com/tc39/proposal-logical-assignment.\n\n* Data loaders now set \"no side effects\"\n\n Files loaded using the `json`, `text`, `base64`, `dataurl`, and `file` loaders are now removed from the bundle if the files that import them never use the imports. This is the same behavior as the `\"sideEffects\": false` setting in `package.json`.\n\n## 0.4.8\n\n* Add the `--metafile` flag ([#140](https://github.com/evanw/esbuild/issues/140))\n\n Pass `--metafile=meta.json` to write metadata about the build to the file `meta.json`. This includes information such as which files are in the bundle, what other files a given file depends on, and how much of each file ended up in the bundle. This is similar to the [stats option in Webpack](https://webpack.js.org/api/stats/).\n\n The format looks like this:\n\n ```ts\n interface Metadata {\n inputs: {\n [path: string]: {\n bytes: number\n imports: {\n path: string\n }[]\n }\n }\n outputs: {\n [path: string]: {\n bytes: number\n inputs: {\n [path: string]: {\n bytesInOutput: number\n }\n }\n }\n }\n }\n ```\n\n* Shorten numeric literals ([#122](https://github.com/evanw/esbuild/issues/122))\n\n Certain numeric literals now use shorter representations in the generated JavaScript code. For example, `123400000` is now written out as `1234e5`.\n\n## 0.4.7\n\n* Fixed `sideEffects` and nested directories\n\n This fixes a bug where `package.json` files with `\"sideEffects\": false` were not respected for files in nested directories. When this bug occurred, bundles could be bigger than necessary. The `sideEffects` hint is now respected if any parent directory contains the hint instead of just the immediate enclosing directory.\n\n* Fixed `sideEffects` and default exports with side effects\n\n This fixes a bug with default exports with side effects inside a `\"sideEffects\": false` context that were imported and used. These exports were incorrectly discarded instead of being retained, which could cause the resulting bundle to crash.\n\n## 0.4.6\n\n* Respect the `sideEffects` field when tree shaking ([#50](https://github.com/evanw/esbuild/issues/50))\n\n Tree shaking now respects `\"sideEffects\": false` in `package.json`, which means esbuild now generates smaller bundles with certain libraries such as [lodash-es](https://www.npmjs.com/package/lodash-es). This setting is a [convention from Webpack](https://webpack.js.org/guides/tree-shaking/#mark-the-file-as-side-effect-free). Any files in a package with this setting will not be included in the bundle if they are imported using an ES6 import and then never used.\n\n## 0.4.5\n\n* Fix a crash with more than 8 entry points ([#162](https://github.com/evanw/esbuild/pull/162))\n\n This bug was due to the wrong index being used for an internal bit set. That caused a crash due to an out-of-bounds array read when esbuild is run with more than 8 entry points. I now have test coverage for large numbers of entry points, so this should not happen again.\n\n* Fix slash characters in file loader ([#164](https://github.com/evanw/esbuild/pull/164))\n\n This fixes a bug where the base64-encoded hash included in the file name could sometimes contain a `/` character. The fix is to use the base64 character set for URL-encoding, which replaces the `/` character with a `_` character.\n\n## 0.4.4\n\n* Fix optional chaining with TypeScript operators ([#168](https://github.com/evanw/esbuild/issues/168))\n\n The work on optional chaining in the previous release introduced a regression where the TypeScript infix operators `!` and `<>` incorrectly stopped the propagation of optional chaining. That meant `a?.b!()` and `a?.b()` incorrectly behaved like `(a?.b)()` instead of `a?.b()`. This now has test coverage.\n\n* Add support for the `\"paths\"` field in `tsconfig.json` ([#60](https://github.com/evanw/esbuild/issues/60) and [#144](https://github.com/evanw/esbuild/issues/144))\n\n This provides a way of remapping module paths to local file paths. It's relatively powerful because it supports wildcard patterns and multiple fallback locations. See [the documentation in the TypeScript handbook](https://www.typescriptlang.org/docs/handbook/module-resolution.html#path-mapping) for more information about how this feature works. This was contributed by [@viankakrisna](https://github.com/viankakrisna).\n\n* Add the `file` loader ([#14](https://github.com/evanw/esbuild/issues/14) and [#135](https://github.com/evanw/esbuild/pull/135))\n\n The `file` loader copies the input file to the output directory and exports the path of the file as a string to any modules that import the file. For example, `--loader:.png=file` enables this loader for all imported `.png` files. This was contributed by [@viankakrisna](https://github.com/viankakrisna).\n\n* Add the `--resolve-extensions` flag ([#142](https://github.com/evanw/esbuild/pull/142))\n\n This lets you override the implicit extensions that are tested when importing a file. It must be a comma-separated list of extensions. For example, setting `--resolve-extensions=.jsx,.js` means `import \"./foo\"` will check for `./foo` then `./foo.jsx` then `./foo.js` in that order. The behavior corresponds to [the similarly-named feature in Webpack](https://webpack.js.org/configuration/resolve/#resolveextensions). This was contributed by [@viankakrisna](https://github.com/viankakrisna).\n\n## 0.4.3\n\n* Fix bug with optional chaining parentheses ([#156](https://github.com/evanw/esbuild/issues/156))\n\n One edge case with JavaScript optional chaining syntax is that parentheses stop the chain. So `a?.b.c` will be `undefined` if `a` is nullish but `(a?.b).c` will crash if `a` is nullish.\n\n This was handled correctly when lowering is enabled (i.e. when the language target is `es2019` or below) but was not handled correctly when lowering is disabled (i.e. when the language target is `es2020` or above). The output for `(a?.b).c` was incorrectly `a?.b.c` instead of `(a?.b).c`, which would no longer crash if `a` is nullish. The fix is to preserve the parentheses in the output.\n\n* Support for the PowerPC 64-bit Little Endian architecture on Linux ([#146](https://github.com/evanw/esbuild/pull/146))\n\n This was contributed by [@runlevel5](https://github.com/runlevel5).\n\n## 0.4.2\n\n* Bind imports to re-exports ([#149](https://github.com/evanw/esbuild/issues/149))\n\n This fixes a bug where imports of re-exported symbols were not correctly merged in some cases. This resulted in the generated code referencing symbols that were not declared, resulting in a crash.\n\n## 0.4.1\n\n* Add a log level setting ([#117](https://github.com/evanw/esbuild/issues/117))\n\n You can now silence esbuild except for errors with `--log-level=error`, or except for errors and warnings with `--log-level=warning`.\n\n* Now `jsconfig.json` is an alternative to `tsconfig.json` ([#132](https://github.com/evanw/esbuild/pull/132))\n\n The `\"baseUrl\"` setting in `tsconfig.json`, which lets you avoid `../../` relative import paths, is respected by esbuild. With this change, esbuild will also check for this setting in `jsconfig.json` if no `tsconfig.json` file is found. This is relevant to some projects that use the TypeScript compiler with JavaScript files instead of TypeScript files. You can read more about this feature [here](https://code.visualstudio.com/docs/languages/jsconfig). This was contributed by [@viankakrisna](https://github.com/viankakrisna).\n\n* Chinese translation of documentation ([#129](https://github.com/evanw/esbuild/pull/129))\n\n Both the readme and the architecture documentation have been translated into Chinese, which is available here: http://docs.breword.com/evanw-esbuild. This was contributed by [@92hackers](https://github.com/92hackers).\n\n* Async generator functions require `--target=es2018`\n\n This fixes a bug where async generator functions were incorrectly allowed with `--target=es2017`, which is incorrect because the [asynchronous iteration spec](https://github.com/tc39/proposal-async-iteration) is part of ES2018.\n\n## 0.4.0\n\n* Add the `esm` output format ([#48](https://github.com/evanw/esbuild/issues/48))\n\n It is now possible to generate a bundle in ES6 module format using `--format=esm`. The generated code uses ES6 import and export statements. This is useful for bundling code to be used as a library, for using in a `\n \n ```\n\n Previously the implementers of these languages had to use the `importsNotUsedAsValues` setting as a hack for esbuild to preserve the import statements. With this release, esbuild now follows the behavior of the TypeScript compiler so implementers will need to use the new `preserveValueImports` setting to do this instead. This is the breaking change.\n\n* TypeScript code follows JavaScript class field semantics with `--target=esnext` ([#1480](https://github.com/evanw/esbuild/issues/1480))\n\n TypeScript 4.3 included a subtle breaking change that wasn't mentioned in the [TypeScript 4.3 blog post](https://devblogs.microsoft.com/typescript/announcing-typescript-4-3/): class fields will now be compiled with different semantics if `\"target\": \"ESNext\"` is present in `tsconfig.json`. Specifically in this case `useDefineForClassFields` will default to `true` when not specified instead of `false`. This means class field behavior in TypeScript code will now match JavaScript instead of doing something else:\n\n ```js\n class Base {\n set foo(value) { console.log('set', value) }\n }\n class Derived extends Base {\n foo = 123\n }\n new Derived()\n ```\n\n In TypeScript 4.2 and below, the TypeScript compiler would generate code that prints `set 123` when `tsconfig.json` contains `\"target\": \"ESNext\"` but in TypeScript 4.3 and above, the TypeScript compiler will now generate code that doesn't print anything. This is the difference between \"assign\" semantics and \"define\" semantics.\n\n Previously you had to create a `tsconfig.json` file and specify `\"target\": \"ESNext\"` to get this behavior in esbuild. With this release, you can now also just pass `--target=esnext` to esbuild to force-enable this behavior. Note that esbuild doesn't do this by default even though the default value of `--target=` otherwise behaves like `esnext`. Since TypeScript's compiler doesn't do this behavior by default, it seems like a good idea for esbuild to not do this behavior by default either.\n\nIn addition to the breaking changes above, the following changes are also included in this release:\n\n* Allow certain keywords as tuple type labels in TypeScript ([#1797](https://github.com/evanw/esbuild/issues/1797))\n\n Apparently TypeScript lets you use certain keywords as tuple labels but not others. For example, `type x = [function: number]` is allowed while `type x = [class: number]` isn't. This release replicates this behavior in esbuild's TypeScript parser:\n\n * Allowed keywords: `false`, `function`, `import`, `new`, `null`, `this`, `true`, `typeof`, `void`\n\n * Forbidden keywords: `break`, `case`, `catch`, `class`, `const`, `continue`, `debugger`, `default`, `delete`, `do`, `else`, `enum`, `export`, `extends`, `finally`, `for`, `if`, `in`, `instanceof`, `return`, `super`, `switch`, `throw`, `try`, `var`, `while`, `with`\n\n* Support sibling namespaces in TypeScript ([#1410](https://github.com/evanw/esbuild/issues/1410))\n\n TypeScript has a feature where sibling namespaces with the same name can implicitly reference each other's exports without an explicit property access. This goes against how scope lookup works in JavaScript, so it previously didn't work with esbuild. This release adds support for this feature:\n\n ```ts\n // Original TypeScript code\n namespace x {\n export let y = 123\n }\n namespace x {\n export let z = y\n }\n\n // Old JavaScript output\n var x;\n (function(x2) {\n x2.y = 123;\n })(x || (x = {}));\n (function(x2) {\n x2.z = y;\n })(x || (x = {}));\n\n // New JavaScript output\n var x;\n (function(x2) {\n x2.y = 123;\n })(x || (x = {}));\n (function(x2) {\n x2.z = x2.y;\n })(x || (x = {}));\n ```\n\n Notice how the identifier `y` is now compiled to the property access `x2.y` which references the export named `y` on the namespace, instead of being left as the identifier `y` which references the global named `y`. This matches how the TypeScript compiler treats namespace objects. This new behavior also works for enums:\n\n ```ts\n // Original TypeScript code\n enum x {\n y = 123\n }\n enum x {\n z = y + 1\n }\n\n // Old JavaScript output\n var x;\n (function(x2) {\n x2[x2[\"y\"] = 123] = \"y\";\n })(x || (x = {}));\n (function(x2) {\n x2[x2[\"z\"] = y + 1] = \"z\";\n })(x || (x = {}));\n\n // New JavaScript output\n var x;\n (function(x2) {\n x2[x2[\"y\"] = 123] = \"y\";\n })(x || (x = {}));\n (function(x2) {\n x2[x2[\"z\"] = 124] = \"z\";\n })(x || (x = {}));\n ```\n\n Note that this behavior does **not** work across files. Each file is still compiled independently so the namespaces in each file are still resolved independently per-file. Implicit namespace cross-references still do not work across files. Getting this to work is counter to esbuild's parallel architecture and does not fit in with esbuild's design. It also doesn't make sense with esbuild's bundling model where input files are either in ESM or CommonJS format and therefore each have their own scope.\n\n* Change output for top-level TypeScript enums\n\n The output format for top-level TypeScript enums has been changed to reduce code size and improve tree shaking, which means that esbuild's enum output is now somewhat different than TypeScript's enum output. The behavior of both output formats should still be equivalent though. Here's an example that shows the difference:\n\n ```ts\n // Original code\n enum x {\n y = 1,\n z = 2\n }\n\n // Old output\n var x;\n (function(x2) {\n x2[x2[\"y\"] = 1] = \"y\";\n x2[x2[\"z\"] = 2] = \"z\";\n })(x || (x = {}));\n\n // New output\n var x = /* @__PURE__ */ ((x2) => {\n x2[x2[\"y\"] = 1] = \"y\";\n x2[x2[\"z\"] = 2] = \"z\";\n return x2;\n })(x || {});\n ```\n\n The function expression has been changed to an arrow expression to reduce code size and the enum initializer has been moved into the variable declaration to make it possible to be marked as `/* @__PURE__ */` to improve tree shaking. The `/* @__PURE__ */` annotation is now automatically added when all of the enum values are side-effect free, which means the entire enum definition can be removed as dead code if it's never referenced. Direct enum value references within the same file that have been inlined do not count as references to the enum definition so this should eliminate enums from the output in many cases:\n\n ```ts\n // Original code\n enum Foo { FOO = 1 }\n enum Bar { BAR = 2 }\n console.log(Foo, Bar.BAR)\n\n // Old output (with --bundle --minify)\n var n;(function(e){e[e.FOO=1]=\"FOO\"})(n||(n={}));var l;(function(e){e[e.BAR=2]=\"BAR\"})(l||(l={}));console.log(n,2);\n\n // New output (with --bundle --minify)\n var n=(e=>(e[e.FOO=1]=\"FOO\",e))(n||{});console.log(n,2);\n ```\n\n Notice how the new output is much shorter because the entire definition for `Bar` has been completely removed as dead code by esbuild's tree shaking.\n\n The output may seem strange since it would be simpler to just have a plain object literal as an initializer. However, TypeScript's enum feature behaves similarly to TypeScript's namespace feature which means enums can merge with existing enums and/or existing namespaces (and in some cases also existing objects) if the existing definition has the same name. This new output format keeps its similarity to the original output format so that it still handles all of the various edge cases that TypeScript's enum feature supports. Initializing the enum using a plain object literal would not merge with existing definitions and would break TypeScript's enum semantics.\n\n* Fix legal comment parsing in CSS ([#1796](https://github.com/evanw/esbuild/issues/1796))\n\n Legal comments in CSS either start with `/*!` or contain `@preserve` or `@license` and are preserved by esbuild in the generated CSS output. This release fixes a bug where non-top-level legal comments inside a CSS file caused esbuild to skip any following legal comments even if those following comments are top-level:\n\n ```css\n /* Original code */\n .example {\n --some-var: var(--tw-empty, /*!*/ /*!*/);\n }\n /*! Some legal comment */\n body {\n background-color: red;\n }\n\n /* Old output (with --minify) */\n .example{--some-var: var(--tw-empty, )}body{background-color:red}\n\n /* New output (with --minify) */\n .example{--some-var: var(--tw-empty, )}/*! Some legal comment */body{background-color:red}\n ```\n\n* Fix panic when printing invalid CSS ([#1803](https://github.com/evanw/esbuild/issues/1803))\n\n This release fixes a panic caused by a conditional CSS `@import` rule with a URL token. Code like this caused esbuild to enter an unexpected state because the case where tokens in the import condition with associated import records wasn't handled. This case is now handled correctly:\n\n ```css\n @import \"example.css\" url(foo);\n ```\n\n* Mark `Set` and `Map` with array arguments as pure ([#1791](https://github.com/evanw/esbuild/issues/1791))\n\n This release introduces special behavior for references to the global `Set` and `Map` constructors that marks them as `/* @__PURE__ */` if they are known to not have any side effects. These constructors evaluate the iterator of whatever is passed to them and the iterator could have side effects, so this is only safe if whatever is passed to them is an array, since the array iterator has no side effects.\n\n Marking a constructor call as `/* @__PURE__ */` means it's safe to remove if the result is unused. This is an existing feature that you can trigger by manually adding a `/* @__PURE__ */` comment before a constructor call. The difference is that this release contains special behavior to automatically mark `Set` and `Map` as pure for you as long as it's safe to do so. As with all constructor calls that are marked `/* @__PURE__ */`, any internal expressions which could cause side effects are still preserved even though the constructor call itself is removed:\n\n ```js\n // Original code\n new Map([\n ['a', b()],\n [c(), new Set(['d', e()])],\n ]);\n\n // Old output (with --minify)\n new Map([[\"a\",b()],[c(),new Set([\"d\",e()])]]);\n\n // New output (with --minify)\n b(),c(),e();\n ```\n\n## 0.13.15\n\n* Fix `super` in lowered `async` arrow functions ([#1777](https://github.com/evanw/esbuild/issues/1777))\n\n This release fixes an edge case that was missed when lowering `async` arrow functions containing `super` property accesses for compile targets that don't support `async` such as with `--target=es6`. The problem was that lowering transforms `async` arrow functions into generator function expressions that are then passed to an esbuild helper function called `__async` that implements the `async` state machine behavior. Since function expressions do not capture `this` and `super` like arrow functions do, this led to a mismatch in behavior which meant that the transform was incorrect. The fix is to introduce a helper function to forward `super` access into the generator function expression body. Here's an example:\n\n ```js\n // Original code\n class Foo extends Bar {\n foo() { return async () => super.bar() }\n }\n\n // Old output (with --target=es6)\n class Foo extends Bar {\n foo() {\n return () => __async(this, null, function* () {\n return super.bar();\n });\n }\n }\n\n // New output (with --target=es6)\n class Foo extends Bar {\n foo() {\n return () => {\n var __superGet = (key) => super[key];\n return __async(this, null, function* () {\n return __superGet(\"bar\").call(this);\n });\n };\n }\n }\n ```\n\n* Avoid merging certain CSS rules with different units ([#1732](https://github.com/evanw/esbuild/issues/1732))\n\n This release no longer collapses `border-radius`, `margin`, `padding`, and `inset` rules when they have units with different levels of browser support. Collapsing multiple of these rules into a single rule is not equivalent if the browser supports one unit but not the other unit, since one rule would still have applied before the collapse but no longer applies after the collapse due to the whole rule being ignored. For example, Chrome 10 supports the `rem` unit but not the `vw` unit, so the CSS code below should render with rounded corners in Chrome 10. However, esbuild previously merged everything into a single rule which would cause Chrome 10 to ignore the rule and not round the corners. This issue is now fixed:\n\n ```css\n /* Original CSS */\n div {\n border-radius: 1rem;\n border-top-left-radius: 1vw;\n margin: 0;\n margin-top: 1Q;\n left: 10Q;\n top: 20Q;\n right: 10Q;\n bottom: 20Q;\n }\n\n /* Old output (with --minify) */\n div{border-radius:1vw 1rem 1rem;margin:1Q 0 0;inset:20Q 10Q}\n\n /* New output (with --minify) */\n div{border-radius:1rem;border-top-left-radius:1vw;margin:0;margin-top:1Q;inset:20Q 10Q}\n ```\n\n Notice how esbuild can still collapse rules together when they all share the same unit, even if the unit is one that doesn't have universal browser support such as the unit `Q`. One subtlety is that esbuild now distinguishes between \"safe\" and \"unsafe\" units where safe units are old enough that they are guaranteed to work in any browser a user might reasonably use, such as `px`. Safe units are allowed to be collapsed together even if there are multiple different units while multiple different unsafe units are not allowed to be collapsed together. Another detail is that esbuild no longer minifies zero lengths by removing the unit if the unit is unsafe (e.g. `0rem` into `0`) since that could cause a rendering difference if a previously-ignored rule is now no longer ignored due to the unit change. If you are curious, you can learn more about browser support levels for different CSS units in [Mozilla's documentation about CSS length units](https://developer.mozilla.org/en-US/docs/Web/CSS/length).\n\n* Avoid warning about ignored side-effect free imports for empty files ([#1785](https://github.com/evanw/esbuild/issues/1785))\n\n When bundling, esbuild warns about bare imports such as `import \"lodash-es\"` when the package has been marked as `\"sideEffects\": false` in its `package.json` file. This is because the only reason to use a bare import is because you are relying on the side effects of the import, but imports for packages marked as side-effect free are supposed to be removed. If the package indicates that it has no side effects, then this bare import is likely a bug.\n\n However, some people have packages just for TypeScript type definitions. These package can actually have a side effect as they can augment the type of the global object in TypeScript, even if they are marked with `\"sideEffects\": false`. To avoid warning in this case, esbuild will now only issue this warning if the imported file is non-empty. If the file is empty, then it's irrelevant whether you import it or not so any import of that file does not indicate a bug. This fixes this case because `.d.ts` files typically end up being empty after esbuild parses them since they typically only contain type declarations.\n\n* Attempt to fix packages broken due to the `node:` prefix ([#1760](https://github.com/evanw/esbuild/issues/1760))\n\n Some people have started using the node-specific `node:` path prefix in their packages. This prefix forces the following path to be interpreted as a node built-in module instead of a package on the file system. So `require(\"node:path\")` will always import [node's `path` module](https://nodejs.org/api/path.html) and never import [npm's `path` package](https://www.npmjs.com/package/path).\n\n Adding the `node:` prefix breaks that code with older node versions that don't understand the `node:` prefix. This is a problem with the package, not with esbuild. The package should be adding a fallback if the `node:` prefix isn't available. However, people still want to be able to use these packages with older node versions even though the code is broken. Now esbuild will automatically strip this prefix if it detects that the code will break in the configured target environment (as specified by `--target=`). Note that this only happens during bundling, since import paths are only examined during bundling.\n\n## 0.13.14\n\n* Fix dynamic `import()` on node 12.20+ ([#1772](https://github.com/evanw/esbuild/issues/1772))\n\n When you use flags such as `--target=node12.20`, esbuild uses that version number to see what features the target environment supports. This consults an internal table that stores which target environments are supported for each feature. For example, `import(x)` is changed into `Promise.resolve().then(() => require(x))` if dynamic `import` expressions are unsupported.\n\n Previously esbuild's internal table only stored one version number, since features are rarely ever removed in newer versions of software. Either the target environment is before that version and the feature is unsupported, or the target environment is after that version and the feature is supported. This approach has work for all relevant features in all cases except for one: dynamic `import` support in node. This feature is supported in node 12.20.0 up to but not including node 13.0.0, and then is also supported in node 13.2.0 up. The feature table implementation has been changed to store an array of potentially discontiguous version ranges instead of one version number.\n\n Up until now, esbuild used 13.2.0 as the lowest supported version number to avoid generating dynamic `import` expressions when targeting node versions that don't support it. But with this release, esbuild will now use the more accurate discontiguous version range in this case. This means dynamic `import` expressions can now be generated when targeting versions of node 12.20.0 up to but not including node 13.0.0.\n\n* Avoid merging certain qualified rules in CSS ([#1776](https://github.com/evanw/esbuild/issues/1776))\n\n A change was introduced in the previous release to merge adjacent CSS rules that have the same content:\n\n ```css\n /* Original code */\n a { color: red }\n b { color: red }\n\n /* Minified output */\n a,b{color:red}\n ```\n\n However, that introduced a regression in cases where the browser considers one selector to be valid and the other selector to be invalid, such as in the following example:\n\n ```css\n /* This rule is valid, and is applied */\n a { color: red }\n\n /* This rule is invalid, and is ignored */\n b:-x-invalid { color: red }\n ```\n\n Merging these two rules into one causes the browser to consider the entire merged rule to be invalid, which disables both rules. This is a change in behavior from the original code.\n\n With this release, esbuild will now only merge adjacent duplicate rules together if they are known to work in all browsers (specifically, if they are known to work in IE 7 and up). Adjacent duplicate rules will no longer be merged in all other cases including modern pseudo-class selectors such as `:focus`, HTML5 elements such as `video`, and combinators such as `a + b`.\n\n* Minify syntax in the CSS `font`, `font-family`, and `font-weight` properties ([#1756](https://github.com/evanw/esbuild/pull/1756))\n\n This release includes size reductions for CSS font syntax when minification is enabled:\n\n ```css\n /* Original code */\n div {\n font: bold 1rem / 1.2 \"Segoe UI\", sans-serif, \"Segoe UI Emoji\";\n }\n\n /* Output with \"--minify\" */\n div{font:700 1rem/1.2 Segoe UI,sans-serif,\"Segoe UI Emoji\"}\n ```\n\n Notice how `bold` has been changed to `700` and the quotes were removed around `\"Segoe UI\"` since it was safe to do so.\n\n This feature was contributed by [@sapphi-red](https://github.com/sapphi-red).\n\n## 0.13.13\n\n* Add more information about skipping `\"main\"` in `package.json` ([#1754](https://github.com/evanw/esbuild/issues/1754))\n\n Configuring `mainFields: []` breaks most npm packages since it tells esbuild to ignore the `\"main\"` field in `package.json`, which most npm packages use to specify their entry point. This is not a bug with esbuild because esbuild is just doing what it was told to do. However, people may do this without understanding how npm packages work, and then be confused about why it doesn't work. This release now includes additional information in the error message:\n\n ```\n > foo.js:1:27: error: Could not resolve \"events\" (use \"--platform=node\" when building for node)\n 1 │ var EventEmitter = require('events')\n ╵ ~~~~~~~~\n node_modules/events/package.json:20:2: note: The \"main\" field was ignored because the list of main fields to use is currently set to []\n 20 │ \"main\": \"./events.js\",\n ╵ ~~~~~~\n ```\n\n* Fix a tree-shaking bug with `var exports` ([#1739](https://github.com/evanw/esbuild/issues/1739))\n\n This release fixes a bug where a variable named `var exports = {}` was incorrectly removed by tree-shaking (i.e. dead code elimination). The `exports` variable is a special variable in CommonJS modules that is automatically provided by the CommonJS runtime. CommonJS modules are transformed into something like this before being run:\n\n ```js\n function(exports, module, require) {\n var exports = {}\n }\n ```\n\n So using `var exports = {}` should have the same effect as `exports = {}` because the variable `exports` should already be defined. However, esbuild was incorrectly overwriting the definition of the `exports` variable with the one provided by CommonJS. This release merges the definitions together so both are included, which fixes the bug.\n\n* Merge adjacent CSS selector rules with duplicate content ([#1755](https://github.com/evanw/esbuild/issues/1755))\n\n With this release, esbuild will now merge adjacent selectors when minifying if they have the same content:\n\n ```css\n /* Original code */\n a { color: red }\n b { color: red }\n\n /* Old output (with --minify) */\n a{color:red}b{color:red}\n\n /* New output (with --minify) */\n a,b{color:red}\n ```\n\n* Shorten `top`, `right`, `bottom`, `left` CSS property into `inset` when it is supported ([#1758](https://github.com/evanw/esbuild/pull/1758))\n\n This release enables collapsing of `inset` related properties:\n\n ```css\n /* Original code */\n div {\n top: 0;\n right: 0;\n bottom: 0;\n left: 0;\n }\n\n /* Output with \"--minify-syntax\" */\n div {\n inset: 0;\n }\n ```\n\n This minification rule is only enabled when `inset` property is supported by the target environment. Make sure to set esbuild's `target` setting correctly when minifying if the code will be running in an older environment (e.g. earlier than Chrome 87).\n\n This feature was contributed by [@sapphi-red](https://github.com/sapphi-red).\n\n## 0.13.12\n\n* Implement initial support for simplifying `calc()` expressions in CSS ([#1607](https://github.com/evanw/esbuild/issues/1607))\n\n This release includes basic simplification of `calc()` expressions in CSS when minification is enabled. The approach mainly follows the official CSS specification, which means it should behave the way browsers behave: https://www.w3.org/TR/css-values-4/#calc-func. This is a basic implementation so there are probably some `calc()` expressions that can be reduced by other tools but not by esbuild. This release mainly focuses on setting up the parsing infrastructure for `calc()` expressions to make it straightforward to implement additional simplifications in the future. Here's an example of this new functionality:\n\n ```css\n /* Input CSS */\n div {\n width: calc(60px * 4 - 5px * 2);\n height: calc(100% / 4);\n }\n\n /* Output CSS (with --minify-syntax) */\n div {\n width: 230px;\n height: 25%;\n }\n ```\n\n Expressions that can't be fully simplified will still be partially simplified into a reduced `calc()` expression:\n\n ```css\n /* Input CSS */\n div {\n width: calc(100% / 5 - 2 * 1em - 2 * 1px);\n }\n\n /* Output CSS (with --minify-syntax) */\n div {\n width: calc(20% - 2em - 2px);\n }\n ```\n\n Note that this transformation doesn't attempt to modify any expression containing a `var()` CSS variable reference. These variable references can contain any number of tokens so it's not safe to move forward with a simplification assuming that `var()` is a single token. For example, `calc(2px * var(--x) * 3)` is not transformed into `calc(6px * var(--x))` in case `var(--x)` contains something like `4 + 5px` (`calc(2px * 4 + 5px * 3)` evaluates to `23px` while `calc(6px * 4 + 5px)` evaluates to `29px`).\n\n* Fix a crash with a legal comment followed by an import ([#1730](https://github.com/evanw/esbuild/issues/1730))\n\n Version 0.13.10 introduced parsing for CSS legal comments but caused a regression in the code that checks whether there are any rules that come before `@import`. This is not desired because browsers ignore `@import` rules after other non-`@import` rules, so esbuild warns you when you do this. However, legal comments are modeled as rules in esbuild's internal AST even though they aren't actual CSS rules, and the code that performs this check wasn't updated. This release fixes the crash.\n\n## 0.13.11\n\n* Implement class static blocks ([#1558](https://github.com/evanw/esbuild/issues/1558))\n\n This release adds support for a new upcoming JavaScript feature called [class static blocks](https://github.com/tc39/proposal-class-static-block) that lets you evaluate code inside of a class body. It looks like this:\n\n ```js\n class Foo {\n static {\n this.foo = 123\n }\n }\n ```\n\n This can be useful when you want to use `try`/`catch` or access private `#name` fields during class initialization. Doing that without this feature is quite hacky and basically involves creating temporary static fields containing immediately-invoked functions and then deleting the fields after class initialization. Static blocks are much more ergonomic and avoid performance loss due to `delete` changing the object shape.\n\n Static blocks are transformed for older browsers by moving the static block outside of the class body and into an immediately invoked arrow function after the class definition:\n\n ```js\n // The transformed version of the example code above\n const _Foo = class {\n };\n let Foo = _Foo;\n (() => {\n _Foo.foo = 123;\n })();\n ```\n\n In case you're wondering, the additional `let` variable is to guard against the potential reassignment of `Foo` during evaluation such as what happens below. The value of `this` must be bound to the original class, not to the current value of `Foo`:\n\n ```js\n let bar\n class Foo {\n static {\n bar = () => this\n }\n }\n Foo = null\n console.log(bar()) // This should not be \"null\"\n ```\n\n* Fix issues with `super` property accesses\n\n Code containing `super` property accesses may need to be transformed even when they are supported. For example, in ES6 `async` methods are unsupported while `super` properties are supported. An `async` method containing `super` property accesses requires those uses of `super` to be transformed (the `async` function is transformed into a nested generator function and the `super` keyword cannot be used inside nested functions).\n\n Previously esbuild transformed `super` property accesses into a function call that returned the corresponding property. However, this was incorrect for uses of `super` that write to the inherited setter since a function call is not a valid assignment target. This release fixes writing to a `super` property:\n\n ```js\n // Original code\n class Base {\n set foo(x) { console.log('set foo to', x) }\n }\n class Derived extends Base {\n async bar() { super.foo = 123 }\n }\n new Derived().bar()\n\n // Old output with --target=es6 (contains a syntax error)\n class Base {\n set foo(x) {\n console.log(\"set foo to\", x);\n }\n }\n class Derived extends Base {\n bar() {\n var __super = (key) => super[key];\n return __async(this, null, function* () {\n __super(\"foo\") = 123;\n });\n }\n }\n new Derived().bar();\n\n // New output with --target=es6 (works correctly)\n class Base {\n set foo(x) {\n console.log(\"set foo to\", x);\n }\n }\n class Derived extends Base {\n bar() {\n var __superSet = (key, value) => super[key] = value;\n return __async(this, null, function* () {\n __superSet(\"foo\", 123);\n });\n }\n }\n new Derived().bar();\n ```\n\n All known edge cases for assignment to a `super` property should now be covered including destructuring assignment and using the unary assignment operators with BigInts.\n\n In addition, this release also fixes a bug where a `static` class field containing a `super` property access was not transformed when it was moved outside of the class body, which can happen when `static` class fields aren't supported.\n\n ```js\n // Original code\n class Base {\n static get foo() {\n return 123\n }\n }\n class Derived extends Base {\n static bar = super.foo\n }\n\n // Old output with --target=es6 (contains a syntax error)\n class Base {\n static get foo() {\n return 123;\n }\n }\n class Derived extends Base {\n }\n __publicField(Derived, \"bar\", super.foo);\n\n // New output with --target=es6 (works correctly)\n class Base {\n static get foo() {\n return 123;\n }\n }\n const _Derived = class extends Base {\n };\n let Derived = _Derived;\n __publicField(Derived, \"bar\", __superStaticGet(_Derived, \"foo\"));\n ```\n\n All known edge cases for `super` inside `static` class fields should be handled including accessing `super` after prototype reassignment of the enclosing class object.\n\n## 0.13.10\n\n* Implement legal comment preservation for CSS ([#1539](https://github.com/evanw/esbuild/issues/1539))\n\n This release adds support for legal comments in CSS the same way they are already supported for JS. A legal comment is one that starts with `/*!` or that contains the text `@license` or `@preserve`. These comments are preserved in output files by esbuild since that follows the intent of the original authors of the code. The specific behavior is controlled via `--legal-comments=` in the CLI and `legalComments` in the JS API, which can be set to any of the following options:\n\n * `none`: Do not preserve any legal comments\n * `inline`: Preserve all rule-level legal comments\n * `eof`: Move all rule-level legal comments to the end of the file\n * `linked`: Move all rule-level legal comments to a `.LEGAL.txt` file and link to them with a comment\n * `external`: Move all rule-level legal comments to a `.LEGAL.txt` file but to not link to them\n\n The default behavior is `eof` when bundling and `inline` otherwise.\n\n* Allow uppercase `es*` targets ([#1717](https://github.com/evanw/esbuild/issues/1717))\n\n With this release, you can now use target names such as `ESNext` instead of `esnext` as the target name in the CLI and JS API. This is important because people don't want to have to call `.toLowerCase()` on target strings from TypeScript's `tsconfig.json` file before passing it to esbuild (TypeScript uses case-agnostic target names).\n\n This feature was contributed by [@timse](https://github.com/timse).\n\n* Update to Unicode 14.0.0\n\n The character tables that determine which characters form valid JavaScript identifiers have been updated from Unicode version 13.0.0 to the newly-released Unicode version 14.0.0. I'm not putting an example in the release notes because all of the new characters will likely just show up as little squares since fonts haven't been updated yet. But you can read https://www.unicode.org/versions/Unicode14.0.0/#Summary for more information about the changes.\n\n## 0.13.9\n\n* Add support for `imports` in `package.json` ([#1691](https://github.com/evanw/esbuild/issues/1691))\n\n This release adds basic support for the `imports` field in `package.json`. It behaves similarly to the `exports` field but only applies to import paths that start with `#`. The `imports` field provides a way for a package to remap its own internal imports for itself, while the `exports` field provides a way for a package to remap its external exports for other packages. This is useful because the `imports` field respects the currently-configured conditions which means that the import mapping can change at run-time. For example:\n\n ```\n $ cat entry.mjs\n import '#example'\n\n $ cat package.json\n {\n \"imports\": {\n \"#example\": {\n \"foo\": \"./example.foo.mjs\",\n \"default\": \"./example.mjs\"\n }\n }\n }\n\n $ cat example.foo.mjs\n console.log('foo is enabled')\n\n $ cat example.mjs\n console.log('foo is disabled')\n\n $ node entry.mjs\n foo is disabled\n\n $ node --conditions=foo entry.mjs\n foo is enabled\n ```\n\n Now that esbuild supports this feature too, import paths starting with `#` and any provided conditions will be respected when bundling:\n\n ```\n $ esbuild --bundle entry.mjs | node\n foo is disabled\n\n $ esbuild --conditions=foo --bundle entry.mjs | node\n foo is enabled\n ```\n\n* Fix using `npm rebuild` with the `esbuild` package ([#1703](https://github.com/evanw/esbuild/issues/1703))\n\n Version 0.13.4 accidentally introduced a regression in the install script where running `npm rebuild` multiple times could fail after the second time. The install script creates a copy of the binary executable using [`link`](https://man7.org/linux/man-pages/man2/link.2.html) followed by [`rename`](https://www.man7.org/linux/man-pages/man2/rename.2.html). Using `link` creates a hard link which saves space on the file system, and `rename` is used for safety since it atomically replaces the destination.\n\n However, the `rename` syscall has an edge case where it silently fails if the source and destination are both the same link. This meant that the install script would fail after being run twice in a row. With this release, the install script now deletes the source after calling `rename` in case it has silently failed, so this issue should now be fixed. It should now be safe to use `npm rebuild` with the `esbuild` package.\n\n* Fix invalid CSS minification of `border-radius` ([#1702](https://github.com/evanw/esbuild/issues/1702))\n\n CSS minification does collapsing of `border-radius` related properties. For example:\n\n ```css\n /* Original CSS */\n div {\n border-radius: 1px;\n border-top-left-radius: 5px;\n }\n\n /* Minified CSS */\n div{border-radius:5px 1px 1px}\n ```\n\n However, this only works for numeric tokens, not identifiers. For example:\n\n ```css\n /* Original CSS */\n div {\n border-radius: 1px;\n border-top-left-radius: inherit;\n }\n\n /* Minified CSS */\n div{border-radius:1px;border-top-left-radius:inherit}\n ```\n\n Transforming this to `div{border-radius:inherit 1px 1px}`, as was done in previous releases of esbuild, is an invalid transformation and results in incorrect CSS. This release of esbuild fixes this CSS transformation bug.\n\n## 0.13.8\n\n* Fix `super` inside arrow function inside lowered `async` function ([#1425](https://github.com/evanw/esbuild/issues/1425))\n\n When an `async` function is transformed into a regular function for target environments that don't support `async` such as `--target=es6`, references to `super` inside that function must be transformed too since the `async`-to-regular function transformation moves the function body into a nested function, so the `super` references are no longer syntactically valid. However, this transform didn't handle an edge case and `super` references inside of an arrow function were overlooked. This release fixes this bug:\n\n ```js\n // Original code\n class Foo extends Bar {\n async foo() {\n return () => super.foo()\n }\n }\n\n // Old output (with --target=es6)\n class Foo extends Bar {\n foo() {\n return __async(this, null, function* () {\n return () => super.foo();\n });\n }\n }\n\n // New output (with --target=es6)\n class Foo extends Bar {\n foo() {\n var __super = (key) => super[key];\n return __async(this, null, function* () {\n return () => __super(\"foo\").call(this);\n });\n }\n }\n ```\n\n* Remove the implicit `/` after `[dir]` in entry names ([#1661](https://github.com/evanw/esbuild/issues/1661))\n\n The \"entry names\" feature lets you customize the way output file names are generated. The `[dir]` and `[name]` placeholders are filled in with the directory name and file name of the corresponding entry point file, respectively.\n\n Previously `--entry-names=[dir]/[name]` and `--entry-names=[dir][name]` behaved the same because the value used for `[dir]` always had an implicit trailing slash, since it represents a directory. However, some people want to be able to remove the file name with `--entry-names=[dir]` and the implicit trailing slash gets in the way.\n\n With this release, you can now use the `[dir]` placeholder without an implicit trailing slash getting in the way. For example, the command `esbuild foo/bar/index.js --outbase=. --outdir=out --entry-names=[dir]` previously generated the file `out/foo/bar/.js` but will now generate the file `out/foo/bar.js`.\n\n## 0.13.7\n\n* Minify CSS alpha values correctly ([#1682](https://github.com/evanw/esbuild/issues/1682))\n\n When esbuild uses the `rgba()` syntax for a color instead of the 8-character hex code (e.g. when `target` is set to Chrome 61 or earlier), the 0-to-255 integer alpha value must be printed as a floating-point fraction between 0 and 1. The fraction was only printed to three decimal places since that is the minimal number of decimal places required for all 256 different alpha values to be uniquely determined. However, using three decimal places does not necessarily result in the shortest result. For example, `128 / 255` is `0.5019607843137255` which is printed as `\".502\"` using three decimal places, but `\".5\"` is equivalent because `round(0.5 * 255) == 128`, so printing `\".5\"` would be better. With this release, esbuild will always use the minimal numeric representation for the alpha value:\n\n ```css\n /* Original code */\n a { color: #FF800080 }\n\n /* Old output (with --minify --target=chrome61) */\n a{color:rgba(255,128,0,.502)}\n\n /* New output (with --minify --target=chrome61) */\n a{color:rgba(255,128,0,.5)}\n ```\n\n* Match node's behavior for core module detection ([#1680](https://github.com/evanw/esbuild/issues/1680))\n\n Node has a hard-coded list of core modules (e.g. `fs`) that, when required, short-circuit the module resolution algorithm and instead return the corresponding internal core module object. When you pass `--platform=node` to esbuild, esbuild also implements this short-circuiting behavior and doesn't try to bundle these import paths. This was implemented in esbuild using the existing `external` feature (e.g. essentially `--external:fs`). However, there is an edge case where esbuild's `external` feature behaved differently than node.\n\n Modules specified via esbuild's `external` feature also cause all sub-paths to be excluded as well, so for example `--external:foo` excludes both `foo` and `foo/bar` from the bundle. However, node's core module check is only an exact equality check, so for example `fs` is a core module and bypasses the module resolution algorithm but `fs/foo` is not a core module and causes the module resolution algorithm to search the file system.\n\n This behavior can be used to load a module on the file system with the same name as one of node's core modules. For example, `require('fs/')` will load the module `fs` from the file system instead of loading node's core `fs` module. With this release, esbuild will now match node's behavior in this edge case. This means the external modules that are automatically added by `--platform=node` now behave subtly differently than `--external:`, which allows code that relies on this behavior to be bundled correctly.\n\n* Fix WebAssembly builds on Go 1.17.2+ ([#1684](https://github.com/evanw/esbuild/pull/1684))\n\n Go 1.17.2 introduces a change (specifically a [fix for CVE-2021-38297](https://go-review.googlesource.com/c/go/+/354591/)) that causes Go's WebAssembly bootstrap script to throw an error when it's run in situations with many environment variables. One such situation is when the bootstrap script is run inside [GitHub Actions](https://github.com/features/actions). This change was introduced because the bootstrap script writes a copy of the environment variables into WebAssembly memory without any bounds checking, and writing more than 4096 bytes of data ends up writing past the end of the buffer and overwriting who-knows-what. So throwing an error in this situation is an improvement. However, this breaks esbuild which previously (at least seemingly) worked fine.\n\n With this release, esbuild's WebAssembly bootstrap script that calls out to Go's WebAssembly bootstrap script will now delete all environment variables except for the ones that esbuild checks for, of which there are currently only four: `NO_COLOR`, `NODE_PATH`, `npm_config_user_agent`, and `WT_SESSION`. This should avoid a crash when esbuild is built using Go 1.17.2+ and should reduce the likelihood of memory corruption when esbuild is built using Go 1.17.1 or earlier. This release also updates the Go version that esbuild ships with to version 1.17.2. Note that this problem only affects the `esbuild-wasm` package. The `esbuild` package is not affected.\n\n See also:\n\n * https://github.com/golang/go/issues/48797\n * https://github.com/golang/go/issues/49011\n\n## 0.13.6\n\n* Emit decorators for `declare` class fields ([#1675](https://github.com/evanw/esbuild/issues/1675))\n\n In version 3.7, TypeScript introduced the `declare` keyword for class fields that avoids generating any code for that field:\n\n ```ts\n // TypeScript input\n class Foo {\n a: number\n declare b: number\n }\n\n // JavaScript output\n class Foo {\n a;\n }\n ```\n\n However, it turns out that TypeScript still emits decorators for these omitted fields. With this release, esbuild will now do this too:\n\n ```ts\n // TypeScript input\n class Foo {\n @decorator a: number;\n @decorator declare b: number;\n }\n\n // Old JavaScript output\n class Foo {\n a;\n }\n __decorateClass([\n decorator\n ], Foo.prototype, \"a\", 2);\n\n // New JavaScript output\n class Foo {\n a;\n }\n __decorateClass([\n decorator\n ], Foo.prototype, \"a\", 2);\n __decorateClass([\n decorator\n ], Foo.prototype, \"b\", 2);\n ```\n\n* Experimental support for esbuild on NetBSD ([#1624](https://github.com/evanw/esbuild/pull/1624))\n\n With this release, esbuild now has a published binary executable for [NetBSD](https://www.netbsd.org/) in the [`esbuild-netbsd-64`](https://www.npmjs.com/package/esbuild-netbsd-64) npm package, and esbuild's installer has been modified to attempt to use it when on NetBSD. Hopefully this makes installing esbuild via npm work on NetBSD. This change was contributed by [@gdt](https://github.com/gdt).\n\n ⚠️ Note: NetBSD is not one of [Node's supported platforms](https://nodejs.org/api/process.html#process_process_platform), so installing esbuild may or may not work on NetBSD depending on how Node has been patched. This is not a problem with esbuild. ⚠️\n\n* Disable the \"esbuild was bundled\" warning if `ESBUILD_BINARY_PATH` is provided ([#1678](https://github.com/evanw/esbuild/pull/1678))\n\n The `ESBUILD_BINARY_PATH` environment variable allows you to substitute an alternate binary executable for esbuild's JavaScript API. This is useful in certain cases such as when debugging esbuild. The JavaScript API has some code that throws an error if it detects that it was bundled before being run, since bundling prevents esbuild from being able to find the path to its binary executable. However, that error is unnecessary if `ESBUILD_BINARY_PATH` is present because an alternate path has been provided. This release disables the warning when `ESBUILD_BINARY_PATH` is present so that esbuild can be used when bundled as long as you also manually specify `ESBUILD_BINARY_PATH`.\n\n This change was contributed by [@heypiotr](https://github.com/heypiotr).\n\n* Remove unused `catch` bindings when minifying ([#1660](https://github.com/evanw/esbuild/pull/1660))\n\n With this release, esbuild will now remove unused `catch` bindings when minifying:\n\n ```js\n // Original code\n try {\n throw 0;\n } catch (e) {\n }\n\n // Old output (with --minify)\n try{throw 0}catch(t){}\n\n // New output (with --minify)\n try{throw 0}catch{}\n ```\n\n This takes advantage of the new [optional catch binding](https://github.com/tc39/proposal-optional-catch-binding) syntax feature that was introduced in ES2019. This minification rule is only enabled when optional catch bindings are supported by the target environment. Specifically, it's not enabled when using `--target=es2018` or older. Make sure to set esbuild's `target` setting correctly when minifying if the code will be running in an older JavaScript environment.\n\n This change was contributed by [@sapphi-red](https://github.com/sapphi-red).\n\n## 0.13.5\n\n* Improve watch mode accuracy ([#1113](https://github.com/evanw/esbuild/issues/1113))\n\n Watch mode is enabled by `--watch` and causes esbuild to become a long-running process that automatically rebuilds output files when input files are changed. It's implemented by recording all calls to esbuild's internal file system interface and then invalidating the build whenever these calls would return different values. For example, a call to esbuild's internal `ReadFile()` function is considered to be different if either the presence of the file has changed (e.g. the file didn't exist before but now exists) or the presence of the file stayed the same but the content of the file has changed.\n\n Previously esbuild's watch mode operated at the `ReadFile()` and `ReadDirectory()` level. When esbuild checked whether a directory entry existed or not (e.g. whether a directory contains a `node_modules` subdirectory or a `package.json` file), it called `ReadDirectory()` which then caused the build to depend on that directory's set of entries. This meant the build would be invalidated even if a new unrelated entry was added or removed, since that still changes the set of entries. This is problematic when using esbuild in environments that constantly create and destroy temporary directory entries in your project directory. In that case, esbuild's watch mode would constantly rebuild as the directory was constantly considered to be dirty.\n\n With this release, watch mode now operates at the `ReadFile()` and `ReadDirectory().Get()` level. So when esbuild checks whether a directory entry exists or not, the build should now only depend on the presence status for that one directory entry. This should avoid unnecessary rebuilds due to unrelated directory entries being added or removed. The log messages generated using `--watch` will now also mention the specific directory entry whose presence status was changed if a build is invalidated for this reason.\n\n Note that this optimization does not apply to plugins using the `watchDirs` return value because those paths are only specified at the directory level and do not describe individual directory entries. You can use `watchFiles` or `watchDirs` on the individual entries inside the directory to get a similar effect instead.\n\n* Disallow certain uses of `<` in `.mts` and `.cts` files\n\n The upcoming version 4.5 of TypeScript is introducing the `.mts` and `.cts` extensions that turn into the `.mjs` and `.cjs` extensions when compiled. However, unlike the existing `.ts` and `.tsx` extensions, expressions that start with `<` are disallowed when they would be ambiguous depending on whether they are parsed in `.ts` or `.tsx` mode. The ambiguity is caused by the overlap between the syntax for JSX elements and the old deprecated syntax for type casts:\n\n | Syntax | `.ts` | `.tsx` | `.mts`/`.cts` |\n |-------------------------------|----------------------|------------------|----------------------|\n | `y` | ✅ Type cast | 🚫 Syntax error | 🚫 Syntax error |\n | `() => {}` | ✅ Arrow function | 🚫 Syntax error | 🚫 Syntax error |\n | `y` | 🚫 Syntax error | ✅ JSX element | 🚫 Syntax error |\n | `() => {}` | 🚫 Syntax error | ✅ JSX element | 🚫 Syntax error |\n | `() => {}` | 🚫 Syntax error | ✅ JSX element | 🚫 Syntax error |\n | `() => {}` | 🚫 Syntax error | ✅ JSX element | 🚫 Syntax error |\n | `() => {}` | ✅ Arrow function | ✅ Arrow function | ✅ Arrow function |\n | `() => {}` | ✅ Arrow function | ✅ Arrow function | ✅ Arrow function |\n\n This release of esbuild introduces a syntax error for these ambiguous syntax constructs in `.mts` and `.cts` files to match the new behavior of the TypeScript compiler.\n\n* Do not remove empty `@keyframes` rules ([#1665](https://github.com/evanw/esbuild/issues/1665))\n\n CSS minification in esbuild automatically removes empty CSS rules, since they have no effect. However, empty `@keyframes` rules still trigger JavaScript animation events so it's incorrect to remove them. To demonstrate that empty `@keyframes` rules still have an effect, here is a bug report for Firefox where it was incorrectly not triggering JavaScript animation events for empty `@keyframes` rules: https://bugzilla.mozilla.org/show_bug.cgi?id=1004377.\n\n With this release, empty `@keyframes` rules are now preserved during minification:\n\n ```css\n /* Original CSS */\n @keyframes foo {\n from {}\n to {}\n }\n\n /* Old output (with --minify) */\n\n /* New output (with --minify) */\n @keyframes foo{}\n ```\n\n This fix was contributed by [@eelco](https://github.com/eelco).\n\n* Fix an incorrect duplicate label error ([#1671](https://github.com/evanw/esbuild/pull/1671))\n\n When labeling a statement in JavaScript, the label must be unique within the enclosing statements since the label determines the jump target of any labeled `break` or `continue` statement:\n\n ```js\n // This code is valid\n x: y: z: break x;\n\n // This code is invalid\n x: y: x: break x;\n ```\n\n However, an enclosing label with the same name *is* allowed as long as it's located in a different function body. Since `break` and `continue` statements can't jump across function boundaries, the label is not ambiguous. This release fixes a bug where esbuild incorrectly treated this valid code as a syntax error:\n\n ```js\n // This code is valid, but was incorrectly considered a syntax error\n x: (() => {\n x: break x;\n })();\n ```\n\n This fix was contributed by [@nevkontakte](https://github.com/nevkontakte).\n\n## 0.13.4\n\n* Fix permission issues with the install script ([#1642](https://github.com/evanw/esbuild/issues/1642))\n\n The `esbuild` package contains a small JavaScript stub file that implements the CLI (command-line interface). Its only purpose is to spawn the binary esbuild executable as a child process and forward the command-line arguments to it.\n\n The install script contains an optimization that replaces this small JavaScript stub with the actual binary executable at install time to avoid the overhead of unnecessarily creating a new `node` process. This optimization can't be done at package publish time because there is only one `esbuild` package but there are many supported platforms, so the binary executable for the current platform must live outside of the `esbuild` package.\n\n However, the optimization was implemented with an [unlink](https://www.man7.org/linux/man-pages/man2/unlink.2.html) operation followed by a [link](https://www.man7.org/linux/man-pages/man2/link.2.html) operation. This means that if the first step fails, the package is left in a broken state since the JavaScript stub file is deleted but not yet replaced.\n\n With this release, the optimization is now implemented with a [link](https://www.man7.org/linux/man-pages/man2/link.2.html) operation followed by a [rename](https://www.man7.org/linux/man-pages/man2/rename.2.html) operation. This should always leave the package in a working state even if either step fails.\n\n* Add a fallback for `npm install esbuild --no-optional` ([#1647](https://github.com/evanw/esbuild/issues/1647))\n\n The installation method for esbuild's platform-specific binary executable was recently changed in version 0.13.0. Before that version esbuild downloaded it in an install script, and after that version esbuild lets the package manager download it using the `optionalDependencies` feature in `package.json`. This change was made because downloading the binary executable in an install script never really fully worked. The reasons are complex but basically there are a variety of edge cases where people people want to install esbuild in environments that they have customized such that downloading esbuild isn't possible. Using `optionalDependencies` instead lets the package manager deal with it instead, which should work fine in all cases (either that or your package manager has a bug, but that's not esbuild's problem).\n\n There is one case where this new installation method doesn't work: if you pass the `--no-optional` flag to npm to disable the `optionalDependencies` feature. If you do this, you prevent esbuild from being installed. This is not a problem with esbuild because you are manually enabling a flag to change npm's behavior such that esbuild doesn't install correctly. However, people still want to do this.\n\n With this release, esbuild will now fall back to the old installation method if the new installation method fails. **THIS MAY NOT WORK.** The new `optionalDependencies` installation method is the only supported way to install esbuild with npm. The old downloading installation method was removed because it doesn't always work. The downloading method is only being provided to try to be helpful but it's not the supported installation method. If you pass `--no-optional` and the download fails due to some environment customization you did, the recommended fix is to just remove the `--no-optional` flag.\n\n* Support the new `.mts` and `.cts` TypeScript file extensions\n\n The upcoming version 4.5 of TypeScript has two new file extensions: `.mts` and `.cts`. Files with these extensions can be imported using the `.mjs` and `.cjs`, respectively. So the statement `import \"./foo.mjs\"` in TypeScript can actually succeed even if the file `./foo.mjs` doesn't exist on the file system as long as the file `./foo.mts` does exist. The import path with the `.mjs` extension is automatically re-routed to the corresponding file with the `.mts` extension at type-checking time by the TypeScript compiler. See [the TypeScript 4.5 beta announcement](https://devblogs.microsoft.com/typescript/announcing-typescript-4-5-beta/#new-file-extensions) for details.\n\n With this release, esbuild will also automatically rewrite `.mjs` to `.mts` and `.cjs` to `.cts` when resolving import paths to files on the file system. This should make it possible to bundle code written in this new style. In addition, the extensions `.mts` and `.cts` are now also considered valid TypeScript file extensions by default along with the `.ts` extension.\n\n* Fix invalid CSS minification of `margin` and `padding` ([#1657](https://github.com/evanw/esbuild/issues/1657))\n\n CSS minification does collapsing of `margin` and `padding` related properties. For example:\n\n ```css\n /* Original CSS */\n div {\n margin: auto;\n margin-top: 5px;\n margin-left: 5px;\n }\n\n /* Minified CSS */\n div{margin:5px auto auto 5px}\n ```\n\n However, while this works for the `auto` keyword, it doesn't work for other keywords. For example:\n\n ```css\n /* Original CSS */\n div {\n margin: inherit;\n margin-top: 5px;\n margin-left: 5px;\n }\n\n /* Minified CSS */\n div{margin:inherit;margin-top:5px;margin-left:5px}\n ```\n\n Transforming this to `div{margin:5px inherit inherit 5px}`, as was done in previous releases of esbuild, is an invalid transformation and results in incorrect CSS. This release of esbuild fixes this CSS transformation bug.\n\n## 0.13.3\n\n* Support TypeScript type-only import/export specifiers ([#1637](https://github.com/evanw/esbuild/pull/1637))\n\n This release adds support for a new TypeScript syntax feature in the upcoming version 4.5 of TypeScript. This feature lets you prefix individual imports and exports with the `type` keyword to indicate that they are types instead of values. This helps tools such as esbuild omit them from your source code, and is necessary because esbuild compiles files one-at-a-time and doesn't know at parse time which imports/exports are types and which are values. The new syntax looks like this:\n\n ```ts\n // Input TypeScript code\n import { type Foo } from 'foo'\n export { type Bar }\n\n // Output JavaScript code (requires \"importsNotUsedAsValues\": \"preserve\" in \"tsconfig.json\")\n import {} from \"foo\";\n export {};\n ```\n\n See [microsoft/TypeScript#45998](https://github.com/microsoft/TypeScript/pull/45998) for full details. From what I understand this is a purely ergonomic improvement since this was already previously possible using a type-only import/export statements like this:\n\n ```ts\n // Input TypeScript code\n import type { Foo } from 'foo'\n export type { Bar }\n import 'foo'\n export {}\n\n // Output JavaScript code (requires \"importsNotUsedAsValues\": \"preserve\" in \"tsconfig.json\")\n import \"foo\";\n export {};\n ```\n\n This feature was contributed by [@g-plane](https://github.com/g-plane).\n\n## 0.13.2\n\n* Fix `export {}` statements with `--tree-shaking=true` ([#1628](https://github.com/evanw/esbuild/issues/1628))\n\n The new `--tree-shaking=true` option allows you to force-enable tree shaking in cases where it wasn't previously possible. One such case is when bundling is disabled and there is no output format configured, in which case esbuild just preserves the format of whatever format the input code is in. Enabling tree shaking in this context caused a bug where `export {}` statements were stripped. This release fixes the bug so `export {}` statements should now be preserved when you pass `--tree-shaking=true`. This bug only affected this new functionality and didn't affect existing scenarios.\n\n## 0.13.1\n\n* Fix the `esbuild` package in yarn 2+\n\n The [yarn package manager](https://yarnpkg.com/) version 2 and above has a mode called [PnP](https://next.yarnpkg.com/features/pnp/) that installs packages inside zip files instead of using individual files on disk, and then hijacks node's `fs` module to pretend that paths to files inside the zip file are actually individual files on disk so that code that wasn't written specifically for yarn still works. Unfortunately that hijacking is incomplete and it still causes certain things to break such as using these zip file paths to create a JavaScript worker thread or to create a child process.\n\n This was an issue for the new `optionalDependencies` package installation strategy that was just released in version 0.13.0 since the binary executable is now inside of an installed package instead of being downloaded using an install script. When it's installed with yarn 2+ in PnP mode the binary executable is inside a zip file and can't be run. To work around this, esbuild detects yarn's PnP mode and copies the binary executable to a real file outside of the zip file.\n\n Unfortunately the code to do this didn't create the parent directory before writing to the file path. That caused esbuild's API to crash when it was run for the first time. This didn't come up during testing because the parent directory already existed when the tests were run. This release changes the location of the binary executable from a shared cache directory to inside the esbuild package itself, which should fix this crash. This problem only affected esbuild's JS API when it was run through yarn 2+ with PnP mode active.\n\n## 0.13.0\n\n**This release contains backwards-incompatible changes.** Since esbuild is before version 1.0.0, these changes have been released as a new minor version to reflect this (as [recommended by npm](https://docs.npmjs.com/cli/v6/using-npm/semver/)). You should either be pinning the exact version of `esbuild` in your `package.json` file or be using a version range syntax that only accepts patch upgrades such as `~0.12.0`. See the documentation about [semver](https://docs.npmjs.com/cli/v6/using-npm/semver/) for more information.\n\n* Allow tree shaking to be force-enabled and force-disabled ([#1518](https://github.com/evanw/esbuild/issues/1518), [#1610](https://github.com/evanw/esbuild/issues/1610), [#1611](https://github.com/evanw/esbuild/issues/1611), [#1617](https://github.com/evanw/esbuild/pull/1617))\n\n This release introduces a breaking change that gives you more control over when tree shaking happens (\"tree shaking\" here refers to declaration-level dead code removal). Previously esbuild's tree shaking was automatically enabled or disabled for you depending on the situation and there was no manual override to change this. Specifically, tree shaking was only enabled either when bundling was enabled or when the output format was set to `iife` (i.e. wrapped in an immediately-invoked function expression). This was done to avoid issues with people appending code to output files in the `cjs` and `esm` formats and expecting that code to be able to reference code in the output file that isn't otherwise referenced.\n\n You now have the ability to explicitly force-enable or force-disable tree shaking to bypass this default behavior. This is a breaking change because there is already a setting for tree shaking that does something else, and it has been moved to a separate setting instead. The previous setting allowed you to control whether or not to ignore manual side-effect annotations, which is related to tree shaking since only side-effect free code can be removed as dead code. Specifically you can annotate function calls with `/* @__PURE__ */` to indicate that they can be removed if they are not used, and you can annotate packages with `\"sideEffects\": false` to indicate that imports of that package can be removed if they are not used. Being able to ignore these annotations is necessary because [they are sometimes incorrect](https://github.com/tensorflow/tfjs/issues/4248). This previous setting has been moved to a separate setting because it actually impacts dead-code removal within expressions, which also applies when minifying with tree-shaking disabled.\n\n ### Old behavior\n\n * CLI\n * Ignore side-effect annotations: `--tree-shaking=ignore-annotations`\n * JS\n * Ignore side-effect annotations: `treeShaking: 'ignore-annotations'`\n * Go\n * Ignore side-effect annotations: `TreeShaking: api.TreeShakingIgnoreAnnotations`\n\n ### New behavior\n\n * CLI\n * Ignore side-effect annotations: `--ignore-annotations`\n * Force-disable tree shaking: `--tree-shaking=false`\n * Force-enable tree shaking: `--tree-shaking=true`\n * JS\n * Ignore side-effect annotations: `ignoreAnnotations: true`\n * Force-disable tree shaking: `treeShaking: false`\n * Force-enable tree shaking: `treeShaking: true`\n * Go\n * Ignore side-effect annotations: `IgnoreAnnotations: true`\n * Force-disable tree shaking: `TreeShaking: api.TreeShakingFalse`\n * Force-enable tree shaking: `TreeShaking: api.TreeShakingTrue`\n\n* The npm package now uses `optionalDependencies` to install the platform-specific binary executable ([#286](https://github.com/evanw/esbuild/issues/286), [#291](https://github.com/evanw/esbuild/issues/291), [#319](https://github.com/evanw/esbuild/issues/319), [#347](https://github.com/evanw/esbuild/issues/347), [#369](https://github.com/evanw/esbuild/issues/369), [#547](https://github.com/evanw/esbuild/issues/547), [#565](https://github.com/evanw/esbuild/issues/565), [#789](https://github.com/evanw/esbuild/issues/789), [#921](https://github.com/evanw/esbuild/issues/921), [#1193](https://github.com/evanw/esbuild/issues/1193), [#1270](https://github.com/evanw/esbuild/issues/1270), [#1382](https://github.com/evanw/esbuild/issues/1382), [#1422](https://github.com/evanw/esbuild/issues/1422), [#1450](https://github.com/evanw/esbuild/issues/1450), [#1485](https://github.com/evanw/esbuild/issues/1485), [#1546](https://github.com/evanw/esbuild/issues/1546), [#1547](https://github.com/evanw/esbuild/pull/1547), [#1574](https://github.com/evanw/esbuild/issues/1574), [#1609](https://github.com/evanw/esbuild/issues/1609))\n\n This release changes esbuild's installation strategy in an attempt to improve compatibility with edge cases such as custom registries, custom proxies, offline installations, read-only file systems, or when post-install scripts are disabled. It's being treated as a breaking change out of caution because it's a significant change to how esbuild works with JS package managers, and hasn't been widely tested yet.\n\n **The old installation strategy** manually downloaded the correct binary executable in a [post-install script](https://docs.npmjs.com/cli/v7/using-npm/scripts). The binary executable is hosted in a separate platform-specific npm package such as [`esbuild-darwin-64`](https://www.npmjs.com/package/esbuild-darwin-64). The install script first attempted to download the package via the `npm` command in case npm had custom network settings configured. If that didn't work, the install script attempted to download the package from https://registry.npmjs.org/ before giving up. This was problematic for many reasons including:\n\n * Not all of npm's settings can be forwarded due to npm bugs such as https://github.com/npm/cli/issues/2284, and npm has said these bugs will never be fixed.\n * Some people have configured their network environments such that downloading from https://registry.npmjs.org/ will hang instead of either succeeding or failing.\n * The installed package was broken if you used `npm --ignore-scripts` because then the post-install script wasn't run. Some people enable this option so that malicious packages must be run first before being able to do malicious stuff.\n\n **The new installation strategy** automatically downloads the correct binary executable using npm's `optionalDependencies` feature to depend on all esbuild packages for all platforms but only have the one for the current platform be installed. This is a built-in part of the package manager so my assumption is that it should work correctly in all of these edge cases that currently don't work. And if there's an issue with this, then the problem is with the package manager instead of with esbuild so this should hopefully reduce the maintenance burden on esbuild itself. Changing to this installation strategy has these drawbacks:\n\n * Old versions of certain package managers (specifically npm and yarn) print lots of useless log messages during the installation, at least one for each platform other than the current one. These messages are harmless and can be ignored. However, they are annoying. There is nothing I can do about this. If you have this problem, one solution is to upgrade your package manager to a newer version.\n\n * Installation will be significantly slower in old versions of npm, old versions of pnpm, and all versions of yarn. These package managers download all packages for all platforms even though they aren't needed and actually cannot be used. This problem has been fixed in npm and pnpm and the problem has been communicated to yarn: https://github.com/yarnpkg/berry/issues/3317. If you have this problem, one solution is to use a newer version of npm or pnpm as your package manager.\n\n * This installation strategy does not work if you use `npm --no-optional` since then the package with the binary executable is not installed. If you have this problem, the solution is to not pass the `--no-optional` flag when installing packages.\n\n * There is still a small post-install script but it's now optional in that the `esbuild` package should still function correctly if post-install scripts are disabled (such as with `npm --ignore-scripts`). This post-install script optimizes the installed package by replacing the `esbuild` JavaScript command shim with the actual binary executable at install time. This avoids the overhead of launching another `node` process when using the `esbuild` command. So keep in mind that installing with `--ignore-scripts` will result in a slower `esbuild` command.\n\n Despite the drawbacks of the new installation strategy, I believe this change is overall a good thing to move forward with. It should fix edge case scenarios where installing esbuild currently doesn't work at all, and this only comes at the expense of the install script working in a less-optimal way (but still working) if you are using an old version of npm. So I'm going to switch installation strategies and see how it goes.\n\n The platform-specific binary executables are still hosted on npm in the same way, so anyone who wrote code that downloads builds from npm using the instructions here should not have to change their code: https://esbuild.github.io/getting-started/#download-a-build. However, note that these platform-specific packages no longer specify the `bin` field in `package.json` so the `esbuild` command will no longer be automatically put on your path. The `bin` field had to be removed because of a collision with the `bin` field of the `esbuild` package (now that the `esbuild` package depends on all of these platform-specific packages as optional dependencies).\n\nIn addition to the breaking changes above, the following features are also included in this release:\n\n* Treat `x` guarded by `typeof x !== 'undefined'` as side-effect free\n\n This is a small tree-shaking (i.e. dead code removal) improvement. Global identifier references are considered to potentially have side effects since they will throw a reference error if the global identifier isn't defined, and code with side effects cannot be removed as dead code. However, there's a somewhat-common case where the identifier reference is guarded by a `typeof` check to check that it's defined before accessing it. With this release, code that does this will now be considered to have no side effects which allows it to be tree-shaken:\n\n ```js\n // Original code\n var __foo = typeof foo !== 'undefined' && foo;\n var __bar = typeof bar !== 'undefined' && bar;\n console.log(__bar);\n\n // Old output (with --bundle, which enables tree-shaking)\n var __foo = typeof foo !== 'undefined' && foo;\n var __bar = typeof bar !== 'undefined' && bar;\n console.log(__bar);\n\n // New output (with --bundle, which enables tree-shaking)\n var __bar = typeof bar !== 'undefined' && bar;\n console.log(__bar);\n ```\n\n## 0.12.29\n\n* Fix compilation of abstract class fields in TypeScript ([#1623](https://github.com/evanw/esbuild/issues/1623))\n\n This release fixes a bug where esbuild could incorrectly include a TypeScript abstract class field in the compiled JavaScript output. This is incorrect because the official TypeScript compiler never does this. Note that this only happened in scenarios where TypeScript's `useDefineForClassFields` setting was set to `true` (or equivalently where TypeScript's `target` setting was set to `ESNext`). Here is the difference:\n\n ```js\n // Original code\n abstract class Foo {\n abstract foo: any;\n }\n\n // Old output\n class Foo {\n foo;\n }\n\n // New output\n class Foo {\n }\n ```\n\n* Proxy from the `__require` shim to `require` ([#1614](https://github.com/evanw/esbuild/issues/1614))\n\n Some background: esbuild's bundler emulates a CommonJS environment. The bundling process replaces the literal syntax `require()` with the referenced module at compile-time. However, other uses of `require` such as `require(someFunction())` are not bundled since the value of `someFunction()` depends on code evaluation, and esbuild does not evaluate code at compile-time. So it's possible for some references to `require` to remain after bundling.\n\n This was causing problems for some CommonJS code that was run in the browser and that expected `typeof require === 'function'` to be true (see [#1202](https://github.com/evanw/esbuild/issues/1202)), since the browser does not provide a global called `require`. Thus esbuild introduced a shim `require` function called `__require` (shown below) and replaced all references to `require` in the bundled code with `__require`:\n\n ```js\n var __require = x => {\n if (typeof require !== 'undefined') return require(x);\n throw new Error('Dynamic require of \"' + x + '\" is not supported');\n };\n ```\n\n However, this broke code that referenced `require.resolve` inside the bundle, which could hypothetically actually work since you could assign your own implementation to `window.require.resolve` (see [#1579](https://github.com/evanw/esbuild/issues/1579)). So the implementation of `__require` was changed to this:\n\n ```js\n var __require = typeof require !== 'undefined' ? require : x => {\n throw new Error('Dynamic require of \"' + x + '\" is not supported');\n };\n ```\n\n However, that broke code that assigned to `window.require` later on after the bundle was loaded ([#1614](https://github.com/evanw/esbuild/issues/1614)). So with this release, the code for `__require` now handles all of these edge cases:\n\n * `typeof require` is still `function` even if `window.require` is undefined\n * `window.require` can be assigned to either before or after the bundle is loaded\n * `require.resolve` and arbitrary other properties can still be accessed\n * `require` will now forward any number of arguments, not just the first one\n\n Handling all of these edge cases is only possible with the [Proxy API](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy). So the implementation of `__require` now looks like this:\n\n ```js\n var __require = (x =>\n typeof require !== 'undefined' ? require :\n typeof Proxy !== 'undefined' ? new Proxy(x, {\n get: (a, b) => (typeof require !== 'undefined' ? require : a)[b]\n }) : x\n )(function(x) {\n if (typeof require !== 'undefined') return require.apply(this, arguments);\n throw new Error('Dynamic require of \"' + x + '\" is not supported');\n });\n ```\n\n* Consider `typeof x` to have no side effects\n\n The `typeof` operator does not itself trigger any code evaluation so it can safely be removed if evaluating the operand does not cause any side effects. However, there is a special case of the `typeof` operator when the operand is an identifier expression. In that case no reference error is thrown if the referenced symbol does not exist (e.g. `typeof x` does not throw an error if there is no symbol named `x`). With this release, esbuild will now consider `typeof x` to have no side effects even if evaluating `x` would have side effects (i.e. would throw a reference error):\n\n ```js\n // Original code\n var unused = typeof React !== 'undefined';\n\n // Old output\n var unused = typeof React !== 'undefined';\n\n // New output\n ```\n\n Note that there is actually an edge case where `typeof x` *can* throw an error: when `x` is being referenced inside of its TDZ, or temporal dead zone (i.e. before it's declared). This applies to `let`, `const`, and `class` symbols. However, esbuild doesn't currently handle TDZ rules so the possibility of errors thrown due to TDZ rules is not currently considered. This typically doesn't matter in real-world code so this hasn't been a priority to fix (and is actually tricky to fix with esbuild's current bundling approach). So esbuild may incorrectly remove a `typeof` expression that actually has side effects. However, esbuild already incorrectly did this in previous releases so its behavior regarding `typeof` and TDZ rules hasn't changed in this release.\n\n## 0.12.28\n\n* Fix U+30FB and U+FF65 in identifier names in ES5 vs. ES6+ ([#1599](https://github.com/evanw/esbuild/issues/1599))\n\n The ES6 specification caused two code points that were previously valid in identifier names in ES5 to no longer be valid in identifier names in ES6+. The two code points are:\n\n * `U+30FB` i.e. `KATAKANA MIDDLE DOT` i.e. `・`\n * `U+FF65` i.e. `HALFWIDTH KATAKANA MIDDLE DOT` i.e. `･`\n\n This means that using ES6+ parsing rules will fail to parse some valid ES5 code, and generating valid ES5 code may fail to be parsed using ES6+ parsing rules. For example, esbuild would previously fail to parse `x.y･` even though it's valid ES5 code (since it's not valid ES6+ code) and esbuild could generate `{y･:x}` when minifying even though it's not valid ES6+ code (since it's valid ES5 code). This problem is the result of my incorrect assumption that ES6 is a superset of ES5.\n\n As of this release, esbuild will now parse a superset of ES5 and ES6+ and will now quote identifier names when possible if it's not considered to be a valid identifier name in either ES5 or ES6+. In other words, a union of ES5 and ES6 rules is used for parsing and the intersection of ES5 and ES6 rules is used for printing.\n\n* Fix `++` and `--` on class private fields when used with big integers ([#1600](https://github.com/evanw/esbuild/issues/1600))\n\n Previously when esbuild lowered class private fields (e.g. `#foo`) to older JavaScript syntax, the transform of the `++` and `--` was not correct if the value is a big integer such as `123n`. The transform in esbuild is similar to Babel's transform which [has the same problem](https://github.com/babel/babel/issues/13756). Specifically, the code was transformed into code that either adds or subtracts the number `1` and `123n + 1` throws an exception in JavaScript. This problem has been fixed so this should now work fine starting with this release.\n\n## 0.12.27\n\n* Update JavaScript syntax feature compatibility tables ([#1594](https://github.com/evanw/esbuild/issues/1594))\n\n Most JavaScript syntax feature compatibility data is able to be obtained automatically via https://kangax.github.io/compat-table/. However, they are missing data for quite a few new JavaScript features (see ([kangax/compat-table#1034](https://github.com/kangax/compat-table/issues/1034))) so data on these new features has to be added manually. This release manually adds a few new entries:\n\n * Top-level await\n\n This feature lets you use `await` at the top level of a module, outside of an `async` function. Doing this holds up the entire module instantiation operation until the awaited expression is resolved or rejected. This release marks this feature as supported in Edge 89, Firefox 89, and Safari 15 (it was already marked as supported in Chrome 89 and Node 14.8). The data source for this is https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/await.\n\n * Arbitrary module namespace identifier names\n\n This lets you use arbitrary strings as module namespace identifier names as long as they are valid UTF-16 strings. An example is `export { x as \"🍕\" }` which can then be imported as `import { \"🍕\" as y } from \"./example.js\"`. This release marks this feature as supported in Firefox 87 (it was already marked as supported in Chrome 90 and Node 16). The data source for this is https://bugzilla.mozilla.org/show_bug.cgi?id=1670044.\n\n I would also like to add data for Safari. They have recently added support for arbitrary module namespace identifier names (https://bugs.webkit.org/show_bug.cgi?id=217576) and `export * as` (https://bugs.webkit.org/show_bug.cgi?id=214379). However, I have no idea how to determine which Safari release these bugs correspond to so this compatibility data for Safari has been omitted.\n\n* Avoid unnecessary additional log messages after the server is stopped ([#1589](https://github.com/evanw/esbuild/issues/1589))\n\n There is a development server built in to esbuild which is accessible via the `serve()` API call. This returns a promise that resolves to an object with a `stop()` method that immediately terminates the development server. Previously calling this could cause esbuild to print stray log messages since `stop()` could cause plugins to be unregistered while a build is still in progress. With this release, calling `stop()` no longer terminates the development server immediately. It now waits for any active builds to finish first so the builds are not interrupted and left in a confusing state.\n\n* Fix an accidental dependency on Go ≥1.17.0 ([#1585](https://github.com/evanw/esbuild/pull/1585))\n\n The source code of this release no longer uses the `math.MaxInt` constant that was introduced in Go version 1.17.0. This constant was preventing esbuild from being compiled on Go version <1.17.0. This fix was contributed by [@davezuko](https://github.com/davezuko).\n\n## 0.12.26\n\n* Add `--analyze` to print information about the bundle ([#1568](https://github.com/evanw/esbuild/issues/1568))\n\n The `--metafile=` flag tells esbuild to write information about the bundle into the provided metadata file in JSON format. It contains information about the input files and which other files each one imports, as well as the output files and which input files they include. This information is sufficient to answer many questions such as:\n\n * Which files are in my bundle?\n * What's are the biggest files in my bundle?\n * Why is this file included in my bundle?\n\n Previously you had to either write your own code to answer these questions, or use another tool such as https://bundle-buddy.com/esbuild to visualize the data. Starting with this release you can now also use `--analyze` to enable esbuild's built-in visualizer. It looks like this:\n\n ```\n $ esbuild --bundle example.jsx --outfile=out.js --minify --analyze\n\n out.js 27.6kb\n\n ⚡ Done in 6ms\n\n out.js 27.6kb 100.0%\n ├ node_modules/react-dom/cjs/react-dom-server.browser.production.min.js 19.2kb 69.8%\n ├ node_modules/react/cjs/react.production.min.js 5.9kb 21.4%\n ├ node_modules/object-assign/index.js 965b 3.4%\n ├ example.jsx 137b 0.5%\n ├ node_modules/react-dom/server.browser.js 50b 0.2%\n └ node_modules/react/index.js 50b 0.2%\n ```\n\n This tells you what input files were bundled into each output file as well as the final minified size contribution of each input file as well as the percentage of the output file it takes up. You can also enable verbose analysis with `--analyze=verbose` to see why each input file was included (i.e. which files imported it from the entry point file):\n\n ```\n $ esbuild --bundle example.jsx --outfile=out.js --minify --analyze=verbose\n\n out.js 27.6kb\n\n ⚡ Done in 6ms\n\n out.js ─────────────────────────────────────────────────────────────────── 27.6kb ─ 100.0%\n ├ node_modules/react-dom/cjs/react-dom-server.browser.production.min.js ─ 19.2kb ── 69.8%\n │ └ node_modules/react-dom/server.browser.js\n │ └ example.jsx\n ├ node_modules/react/cjs/react.production.min.js ───────────────────────── 5.9kb ── 21.4%\n │ └ node_modules/react/index.js\n │ └ example.jsx\n ├ node_modules/object-assign/index.js ──────────────────────────────────── 965b ──── 3.4%\n │ └ node_modules/react-dom/cjs/react-dom-server.browser.production.min.js\n │ └ node_modules/react-dom/server.browser.js\n │ └ example.jsx\n ├ example.jsx ──────────────────────────────────────────────────────────── 137b ──── 0.5%\n ├ node_modules/react-dom/server.browser.js ──────────────────────────────── 50b ──── 0.2%\n │ └ example.jsx\n └ node_modules/react/index.js ───────────────────────────────────────────── 50b ──── 0.2%\n └ example.jsx\n ```\n\n There is also a JS API for this:\n\n ```js\n const result = await esbuild.build({\n metafile: true,\n ...\n })\n console.log(await esbuild.analyzeMetafile(result.metafile, {\n verbose: true,\n }))\n ```\n\n and a Go API:\n\n ```js\n result := api.Build(api.BuildOptions{\n Metafile: true,\n ...\n })\n fmt.Println(api.AnalyzeMetafile(result.Metafile, api.AnalyzeMetafileOptions{\n Verbose: true,\n }))\n ```\n\n Note that this is not the only way to visualize this data. If you want a visualization that's different than the information displayed here, you can easily build it yourself using the information in the metafile that is generated with the `--metafile=` flag.\n\n Also note that this data is intended for humans, not machines. The specific format of this data may change over time which will likely break any tools that try to parse it. You should not write a tool to parse this data. You should be using the information in the JSON metadata file instead. Everything in this visualization is derived from the JSON metadata so you are not losing out on any information by not using esbuild's output.\n\n* Allow `require.resolve` in non-node builds ([#1579](https://github.com/evanw/esbuild/issues/1579))\n\n With this release, you can now use `require.resolve` in builds when the target platform is set to `browser` instead of `node` as long as the function `window.require.resolve` exists somehow. This was already possible when the platform is `node` but when the platform is `browser`, esbuild generates a no-op shim `require` function for compatibility reasons (e.g. because some code expects `typeof require` must be `\"function\"` even in the browser). The shim previously had a fallback to `window.require` if it exists, but additional properties of the `require` function such as `require.resolve` were not copied over to the shim. Now the shim function is only used if `window.require` is undefined so additional properties such as `require.resolve` should now work.\n\n This change was contributed by [@screetBloom](https://github.com/screetBloom).\n\n## 0.12.25\n\n* Fix a TypeScript parsing edge case with the postfix `!` operator ([#1560](https://github.com/evanw/esbuild/issues/1560))\n\n This release fixes a bug with esbuild's TypeScript parser where the postfix `!` operator incorrectly terminated a member expression after the `new` operator:\n\n ```js\n // Original input\n new Foo!.Bar();\n\n // Old output\n new Foo().Bar();\n\n // New output\n new Foo.Bar();\n ```\n\n The problem was that `!` was considered a postfix operator instead of part of a member expression. It is now considered to be part of a member expression instead, which fixes this edge case.\n\n* Fix a parsing crash with nested private brand checks\n\n This release fixes a bug in the parser where code of the form `#a in #b in c` caused a crash. This code now causes a syntax error instead. Private identifiers are allowed when followed by `in`, but only if the operator precedence level is such that the `in` operator is allowed. The parser was missing the operator precedence check.\n\n* Publish x86-64 binary executables for illumos ([#1562](https://github.com/evanw/esbuild/pull/1562))\n\n This release adds support for the [illumos](https://www.illumos.org/) operating system, which is related to Solaris and SunOS. Support for this platform was contributed by [@hadfl](https://github.com/hadfl).\n\n## 0.12.24\n\n* Fix an edge case with direct `eval` and variable renaming\n\n Use of the direct `eval` construct causes all variable names in the scope containing the direct `eval` and all of its parent scopes to become \"pinned\" and unable to be renamed. This is because the dynamically-evaluated code is allowed to reference any of those variables by name. When this happens esbuild avoids renaming any of these variables, which effectively disables minification for most of the file, and avoids renaming any non-pinned variables to the name of a pinned variable.\n\n However, there was previously a bug where the pinned variable name avoidance only worked for pinned variables in the top-level scope but not in nested scopes. This could result in a non-pinned variable being incorrectly renamed to the name of a pinned variable in certain cases. For example:\n\n ```js\n // Input to esbuild\n return function($) {\n function foo(arg) {\n return arg + $;\n }\n // Direct \"eval\" here prevents \"$\" from being renamed\n // Repeated \"$\" puts \"$\" at the top of the character frequency histogram\n return eval(foo($$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$))\n }(2);\n ```\n\n When this code is minified with `--minify-identifiers`, the non-pinned variable `arg` is incorrectly transformed into `$` resulting in a name collision with the nested pinned variable `$`:\n\n ```js\n // Old output from esbuild (incorrect)\n return function($) {\n function foo($) {\n return $ + $;\n }\n return eval(foo($$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$));\n }(2);\n ```\n\n This is because the non-pinned variable `arg` is renamed to the top character in the character frequency histogram `$` (esbuild uses a character frequency histogram for smaller gzipped output sizes) and the pinned variable `$` was incorrectly not present in the list of variable names to avoid. With this release, the output is now correct:\n\n ```js\n // New output from esbuild (correct)\n return function($) {\n function foo(n) {\n return n + $;\n }\n return eval(foo($$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$));\n }(2);\n ```\n\n Note that even when esbuild handles direct `eval` correctly, using direct `eval` is not recommended because it disables minification for the file and likely won't work correctly in the presence of scope hoisting optimizations. See https://esbuild.github.io/link/direct-eval for more details.\n\n## 0.12.23\n\n* Parsing of rest arguments in certain TypeScript types ([#1553](https://github.com/evanw/esbuild/issues/1553))\n\n This release implements parsing of rest arguments inside object destructuring inside arrow functions inside TypeScript type declarations. Support for rest arguments in this specific syntax was not previously implemented. The following code was incorrectly considered a syntax error before this release, but is no longer considered a syntax error:\n\n ```ts\n type F = ({ ...rest }) => void;\n ```\n\n* Fix error message for `watch: true` and `buildSync` ([#1552](https://github.com/evanw/esbuild/issues/1552))\n\n Watch mode currently only works with the `build` API. Previously using watch mode with the `buildSync` API caused a confusing error message. This release explicitly disallows doing this, so the error message is now more clear.\n\n* Fix an minification bug with the `--keep-names` option ([#1552](https://github.com/evanw/esbuild/issues/1552))\n\n This release fixes a subtle bug that happens with `--keep-names --minify` and nested function declarations in strict mode code. It can be triggered by the following code, which was being compiled incorrectly under those flags:\n\n ```js\n export function outer() {\n {\n function inner() {\n return Math.random();\n }\n const x = inner();\n console.log(x);\n }\n }\n outer();\n ```\n\n The bug was caused by an unfortunate interaction between a few of esbuild's behaviors:\n\n 1. Function declarations inside of nested scopes behave differently in different situations, so esbuild rewrites this function declaration to a local variable initialized to a function expression instead so that it behaves the same in all situations.\n\n More specifically, the interpretation of such function declarations depends on whether or not it currently exists in a strict mode context:\n\n ```\n > (function(){ { function x(){} } return x })()\n function x() {}\n\n > (function(){ 'use strict'; { function x(){} } return x })()\n ❌ Uncaught ReferenceError: x is not defined\n ```\n\n The bundling process sometimes erases strict mode context. For example, different files may have different strict mode status but may be merged into a single file which all shares the same strict mode status. Also, files in ESM format are automatically in strict mode but a bundle output file in IIFE format may not be executed in strict mode. Transforming the nested `function` to a `let` in strict mode and a `var` in non-strict mode means esbuild's output will behave reliably in different environments.\n\n 2. The \"keep names\" feature adds automatic calls to the built-in `__name` helper function to assign the original name to the `.name` property of the minified function object at run-time. That transforms the code into this:\n\n ```js\n let inner = function() {\n return Math.random();\n };\n __name(inner, \"inner\");\n const x = inner();\n console.log(x);\n ```\n\n This injected helper call does not count as a use of the associated function object so that dead-code elimination will still remove the function object as dead code if nothing else uses it. Otherwise dead-code elimination would stop working when the \"keep names\" feature is enabled.\n\n 3. Minification enables an optimization where an initialized variable with a single use immediately following that variable is transformed by inlining the initializer into the use. So for example `var a = 1; return a` is transformed into `return 1`. This code matches this pattern (initialized single-use variable + use immediately following that variable) so the optimization does the inlining, which transforms the code into this:\n\n ```js\n __name(function() {\n return Math.random();\n }, \"inner\");\n const x = inner();\n console.log(x);\n ```\n\n The code is now incorrect because `inner` actually has two uses, although only one was actually counted.\n\n This inlining optimization will now be avoided in this specific case, which fixes the bug without regressing dead-code elimination or initialized variable inlining in any other cases.\n\n## 0.12.22\n\n* Make HTTP range requests more efficient ([#1536](https://github.com/evanw/esbuild/issues/1536))\n\n The local HTTP server built in to esbuild supports [range requests](https://developer.mozilla.org/en-US/docs/Web/HTTP/Range_requests), which are necessary for video playback in Safari. This means you can now use `