Full Code of dtolnay/inherent for AI

Repository: dtolnay/inherent
Branch: master
Commit: 159002670802
Files: 21
Total size: 29.1 KB

Directory structure:
gitextract_a9m06ltv/

├── .github/
│   ├── FUNDING.yml
│   └── workflows/
│       └── ci.yml
├── .gitignore
├── Cargo.toml
├── LICENSE-APACHE
├── LICENSE-MIT
├── README.md
├── src/
│   ├── expand.rs
│   ├── lib.rs
│   ├── parse.rs
│   └── verbatim.rs
└── tests/
    ├── compiletest.rs
    ├── test.rs
    └── ui/
        ├── associated-type.rs
        ├── associated-type.stderr
        ├── blanket-impl.rs
        ├── blanket-impl.stderr
        ├── not-trait-impl.rs
        ├── not-trait-impl.stderr
        ├── not-visible.rs
        └── not-visible.stderr

================================================
FILE CONTENTS
================================================

================================================
FILE: .github/FUNDING.yml
================================================
github: dtolnay


================================================
FILE: .github/workflows/ci.yml
================================================
name: CI

on:
  push:
  pull_request:
  workflow_dispatch:
  schedule: [cron: "40 1 * * *"]

permissions:
  contents: read

env:
  RUSTFLAGS: -Dwarnings

jobs:
  pre_ci:
    uses: dtolnay/.github/.github/workflows/pre_ci.yml@master

  test:
    name: Rust ${{matrix.rust}}
    needs: pre_ci
    if: needs.pre_ci.outputs.continue
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        rust: [nightly, beta, stable, 1.85.0, 1.71.0]
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@master
        with:
          toolchain: ${{matrix.rust}}
      - name: Enable type layout randomization
        run: echo RUSTFLAGS=${RUSTFLAGS}\ -Zrandomize-layout >> $GITHUB_ENV
        if: matrix.rust == 'nightly'
      - run: cargo check
      - run: cargo test
        if: matrix.rust != '1.71.0'
      - uses: actions/upload-artifact@v6
        if: matrix.rust == 'nightly' && always()
        with:
          name: Cargo.lock
          path: Cargo.lock
        continue-on-error: true

  minimal:
    name: Minimal versions
    needs: pre_ci
    if: needs.pre_ci.outputs.continue
    runs-on: ubuntu-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@nightly
      - run: cargo generate-lockfile -Z minimal-versions
      - run: cargo check --locked

  doc:
    name: Documentation
    needs: pre_ci
    if: needs.pre_ci.outputs.continue
    runs-on: ubuntu-latest
    timeout-minutes: 45
    env:
      RUSTDOCFLAGS: -Dwarnings
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@nightly
      - uses: dtolnay/install@cargo-docs-rs
      - run: cargo docs-rs

  clippy:
    name: Clippy
    runs-on: ubuntu-latest
    if: github.event_name != 'pull_request'
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@clippy
      - run: cargo clippy --tests -- -Dclippy::all -Dclippy::pedantic

  miri:
    name: Miri
    needs: pre_ci
    if: needs.pre_ci.outputs.continue
    runs-on: ubuntu-latest
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@miri
      - run: cargo miri setup
      - run: cargo miri test
        env:
          MIRIFLAGS: -Zmiri-strict-provenance

  outdated:
    name: Outdated
    runs-on: ubuntu-latest
    if: github.event_name != 'pull_request'
    timeout-minutes: 45
    steps:
      - uses: actions/checkout@v6
      - uses: dtolnay/rust-toolchain@stable
      - uses: dtolnay/install@cargo-outdated
      - run: cargo outdated --workspace --exit-code 1


================================================
FILE: .gitignore
================================================
/target/
/Cargo.lock


================================================
FILE: Cargo.toml
================================================
[package]
name = "inherent"
version = "1.0.13"
authors = ["David Tolnay <dtolnay@gmail.com>"]
categories = ["rust-patterns", "no-std", "no-std::no-alloc"]
description = "Make trait methods callable without the trait in scope"
documentation = "https://docs.rs/inherent"
edition = "2021"
license = "MIT OR Apache-2.0"
repository = "https://github.com/dtolnay/inherent"
rust-version = "1.71"

[lib]
proc-macro = true

[dependencies]
proc-macro2 = "1.0.74"
quote = "1.0.35"
syn = { version = "2.0.46", features = ["full"] }

[dev-dependencies]
rustversion = "1.0.13"
trybuild = { version = "1.0.108", features = ["diff"] }

[package.metadata.docs.rs]
targets = ["x86_64-unknown-linux-gnu"]
rustdoc-args = [
    "--generate-link-to-definition",
    "--generate-macro-expansion",
    "--extern-html-root-url=core=https://doc.rust-lang.org",
    "--extern-html-root-url=alloc=https://doc.rust-lang.org",
    "--extern-html-root-url=std=https://doc.rust-lang.org",
    "--extern-html-root-url=proc_macro=https://doc.rust-lang.org",
]


================================================
FILE: LICENSE-APACHE
================================================
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                     http://www.apache.org/licenses/

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END OF TERMS AND CONDITIONS


================================================
FILE: LICENSE-MIT
================================================
Permission is hereby granted, free of charge, to any
person obtaining a copy of this software and associated
documentation files (the "Software"), to deal in the
Software without restriction, including without
limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software
is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice
shall be included in all copies or substantial portions
of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.


================================================
FILE: README.md
================================================
\#\[inherent\]
==============

[<img alt="github" src="https://img.shields.io/badge/github-dtolnay/inherent-8da0cb?style=for-the-badge&labelColor=555555&logo=github" height="20">](https://github.com/dtolnay/inherent)
[<img alt="crates.io" src="https://img.shields.io/crates/v/inherent.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/inherent)
[<img alt="docs.rs" src="https://img.shields.io/badge/docs.rs-inherent-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs" height="20">](https://docs.rs/inherent)
[<img alt="build status" src="https://img.shields.io/github/actions/workflow/status/dtolnay/inherent/ci.yml?branch=master&style=for-the-badge" height="20">](https://github.com/dtolnay/inherent/actions?query=branch%3Amaster)

This crate provides an attribute macro to make trait methods callable without
the trait in scope.

```toml
[dependencies]
inherent = "1.0"
```

## Example

```rust
mod types {
    use inherent::inherent;

    trait Trait {
        fn f(self);
    }

    pub struct Struct;

    #[inherent]
    impl Trait for Struct {
        pub fn f(self) {}
    }
}

fn main() {
    // types::Trait is not in scope, but method can be called.
    types::Struct.f();
}
```

Without the `inherent` macro on the trait impl, this would have failed with the
following error:

```console
error[E0599]: no method named `f` found for type `types::Struct` in the current scope
  --> src/main.rs:18:19
   |
8  |     pub struct Struct;
   |     ------------------ method `f` not found for this
...
18 |     types::Struct.f();
   |                   ^
   |
   = help: items from traits can only be used if the trait is implemented and in scope
   = note: the following trait defines an item `f`, perhaps you need to implement it:
           candidate #1: `types::Trait`
```

The `inherent` macro expands to inherent methods on the `Self` type of the trait
impl that forward to the trait methods. In the case above, the generated code
would be:

```rust
impl Struct {
    pub fn f(self) {
        <Self as Trait>::f(self)
    }
}
```

<br>

#### License

<sup>
Licensed under either of <a href="LICENSE-APACHE">Apache License, Version
2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option.
</sup>

<br>

<sub>
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
be dual licensed as above, without any additional terms or conditions.
</sub>


================================================
FILE: src/expand.rs
================================================
use crate::parse::TraitImpl;
use crate::verbatim::VerbatimFn;
use proc_macro2::{Span, TokenStream};
use quote::{quote, quote_spanned};
use syn::{Attribute, FnArg, Ident, ImplItem, Pat, Path, Signature, Visibility};

pub fn inherent(mut input: TraitImpl) -> TokenStream {
    let impl_token = &input.impl_token;
    let generics = &input.generics;
    let where_clause = &input.generics.where_clause;
    let trait_ = &input.trait_;
    let ty = &input.self_ty;

    let fwd_methods: Vec<_> = input
        .items
        .iter()
        .filter_map(|item| match item {
            ImplItem::Fn(method) => Some(fwd_method(
                trait_,
                &method.attrs,
                &method.vis,
                &method.sig,
                method.block.brace_token.span.join(),
            )),
            ImplItem::Verbatim(tokens) => {
                if let Ok(method) = syn::parse2::<VerbatimFn>(tokens.clone()) {
                    Some(fwd_method(
                        trait_,
                        &method.attrs,
                        &method.vis,
                        &method.sig,
                        method.semi_token.span,
                    ))
                } else {
                    None
                }
            }
            _ => None,
        })
        .collect();

    input.items = input
        .items
        .into_iter()
        .filter_map(|item| match item {
            ImplItem::Fn(mut method) => {
                method.vis = Visibility::Inherited;
                Some(ImplItem::Fn(method))
            }
            ImplItem::Verbatim(tokens) => {
                if syn::parse2::<VerbatimFn>(tokens.clone()).is_ok() {
                    None
                } else {
                    Some(ImplItem::Verbatim(tokens))
                }
            }
            item => Some(item),
        })
        .collect();

    let body = quote_spanned!(input.brace_token.span=> { #(#fwd_methods)* });

    quote! {
        #impl_token #generics #ty #where_clause #body

        #input
    }
}

fn fwd_method(
    trait_: &Path,
    attrs: &[Attribute],
    vis: &Visibility,
    sig: &Signature,
    body_span: Span,
) -> TokenStream {
    let constness = &sig.constness;
    let asyncness = &sig.asyncness;
    let unsafety = &sig.unsafety;
    let abi = &sig.abi;
    let fn_token = sig.fn_token;
    let ident = &sig.ident;
    let generics = &sig.generics;
    let output = &sig.output;
    let where_clause = &sig.generics.where_clause;

    let (arg_pat, arg_val): (Vec<_>, Vec<_>) = sig
        .inputs
        .pairs()
        .enumerate()
        .map(|(i, pair)| {
            let (input, comma_token) = pair.into_tuple();
            match input {
                FnArg::Receiver(receiver) => {
                    let self_token = receiver.self_token;
                    if receiver.reference.is_some() {
                        (quote!(#receiver #comma_token), quote!(#self_token))
                    } else {
                        (quote!(#self_token #comma_token), quote!(#self_token))
                    }
                }
                FnArg::Typed(arg) => {
                    let var = match arg.pat.as_ref() {
                        Pat::Ident(pat) => pat.ident.clone(),
                        _ => Ident::new(&format!("__arg{}", i), Span::call_site()),
                    };
                    let colon_token = arg.colon_token;
                    let ty = &arg.ty;
                    (quote!(#var #colon_token #ty #comma_token), quote!(#var))
                }
            }
        })
        .unzip();

    let types = generics.type_params().map(|param| &param.ident);
    let wait = asyncness.map(|_| quote!(.await));
    let body = quote!(<Self as #trait_>::#ident::<#(#types,)*>(#(#arg_val,)*) #wait);
    let block = quote_spanned!(body_span=> { #body });
    let args = quote_spanned!(sig.paren_token.span=> (#(#arg_pat)*));

    let has_doc = attrs.iter().any(|attr| attr.path().is_ident("doc"));
    let default_doc = if has_doc {
        None
    } else {
        let mut link = String::new();
        for segment in &trait_.segments {
            link += &segment.ident.to_string();
            link += "::";
        }
        let msg = format!("See [`{}{}`]", link, ident);
        Some(quote!(#[doc = #msg]))
    };

    quote! {
        #(#attrs)*
        #default_doc
        #vis #constness #asyncness #unsafety #abi #fn_token #ident #generics #args #output #where_clause #block
    }
}


================================================
FILE: src/lib.rs
================================================
//! [![github]](https://github.com/dtolnay/inherent)&ensp;[![crates-io]](https://crates.io/crates/inherent)&ensp;[![docs-rs]](https://docs.rs/inherent)
//!
//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs
//!
//! <br>
//!
//! ##### An attribute macro to make trait methods callable without the trait in scope.
//!
//! # Example
//!
//! ```rust
//! mod types {
//!     use inherent::inherent;
//!
//!     trait Trait {
//!         fn f(self);
//!     }
//!
//!     pub struct Struct;
//!
//!     #[inherent]
//!     impl Trait for Struct {
//!         pub fn f(self) {}
//!     }
//! }
//!
//! fn main() {
//!     // types::Trait is not in scope, but method can be called.
//!     types::Struct.f();
//! }
//! ```
//!
//! Without the `inherent` macro on the trait impl, this would have failed with the
//! following error:
//!
//! ```console
//! error[E0599]: no method named `f` found for type `types::Struct` in the current scope
//!   --> src/main.rs:18:19
//!    |
//! 8  |     pub struct Struct;
//!    |     ------------------ method `f` not found for this
//! ...
//! 18 |     types::Struct.f();
//!    |                   ^
//!    |
//!    = help: items from traits can only be used if the trait is implemented and in scope
//!    = note: the following trait defines an item `f`, perhaps you need to implement it:
//!            candidate #1: `types::Trait`
//! ```
//!
//! The `inherent` macro expands to inherent methods on the `Self` type of the trait
//! impl that forward to the trait methods. In the case above, the generated code
//! would be:
//!
//! ```rust
//! # trait Trait {
//! #     fn f(self);
//! # }
//! #
//! # pub struct Struct;
//! #
//! # impl Trait for Struct {
//! #     fn f(self) {}
//! # }
//! #
//! impl Struct {
//!     pub fn f(self) {
//!         <Self as Trait>::f(self)
//!     }
//! }
//! ```

#![doc(html_root_url = "https://docs.rs/inherent/1.0.13")]
#![allow(
    clippy::default_trait_access,
    clippy::module_name_repetitions,
    clippy::needless_doctest_main,
    clippy::needless_pass_by_value,
    clippy::uninlined_format_args
)]

extern crate proc_macro;

mod expand;
mod parse;
mod verbatim;

use proc_macro::TokenStream;
use syn::parse::Nothing;
use syn::parse_macro_input;

use crate::parse::TraitImpl;

#[proc_macro_attribute]
pub fn inherent(args: TokenStream, input: TokenStream) -> TokenStream {
    parse_macro_input!(args as Nothing);
    let input = parse_macro_input!(input as TraitImpl);
    expand::inherent(input).into()
}


================================================
FILE: src/parse.rs
================================================
use proc_macro2::{Span, TokenStream};
use quote::ToTokens;
use syn::parse::{Error, Parse, ParseStream, Result};
use syn::token::Brace;
use syn::{Attribute, Generics, ImplItem, ItemImpl, Path, Token, Type};

#[derive(Clone)]
pub struct TraitImpl {
    pub attrs: Vec<Attribute>,
    pub defaultness: Option<Token![default]>,
    pub unsafety: Option<Token![unsafe]>,
    pub impl_token: Token![impl],
    pub generics: Generics,
    pub trait_: Path,
    pub for_token: Token![for],
    pub self_ty: Type,
    pub brace_token: Brace,
    pub items: Vec<ImplItem>,
}

impl Parse for TraitImpl {
    fn parse(input: ParseStream) -> Result<Self> {
        let imp: ItemImpl = input.parse()?;

        let Some((_bang_token, trait_, for_token)) = imp.trait_ else {
            return Err(Error::new(
                Span::call_site(),
                "must be placed on a trait impl",
            ));
        };

        Ok(TraitImpl {
            attrs: imp.attrs,
            defaultness: imp.defaultness,
            unsafety: imp.unsafety,
            impl_token: imp.impl_token,
            generics: imp.generics,
            trait_,
            for_token,
            self_ty: *imp.self_ty,
            brace_token: imp.brace_token,
            items: imp.items,
        })
    }
}

impl ToTokens for TraitImpl {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        let imp = self.clone();

        ItemImpl::to_tokens(
            &ItemImpl {
                attrs: imp.attrs,
                defaultness: imp.defaultness,
                unsafety: imp.unsafety,
                impl_token: imp.impl_token,
                generics: imp.generics,
                trait_: Some((None, imp.trait_, imp.for_token)),
                self_ty: Box::new(imp.self_ty),
                brace_token: imp.brace_token,
                items: imp.items,
            },
            tokens,
        );
    }
}


================================================
FILE: src/verbatim.rs
================================================
use proc_macro2::TokenStream;
use quote::{ToTokens, TokenStreamExt};
use syn::parse::{Parse, ParseStream, Result};
use syn::{Attribute, Signature, Token, Visibility};

pub struct VerbatimFn {
    pub attrs: Vec<Attribute>,
    pub vis: Visibility,
    pub defaultness: Option<Token![default]>,
    pub sig: Signature,
    pub semi_token: Token![;],
}

impl Parse for VerbatimFn {
    fn parse(input: ParseStream) -> Result<Self> {
        Ok(VerbatimFn {
            attrs: input.call(Attribute::parse_outer)?,
            vis: input.parse()?,
            defaultness: input.parse()?,
            sig: input.parse()?,
            semi_token: input.parse()?,
        })
    }
}

impl ToTokens for VerbatimFn {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        tokens.append_all(&self.attrs);
        self.vis.to_tokens(tokens);
        self.defaultness.to_tokens(tokens);
        self.sig.to_tokens(tokens);
        self.semi_token.to_tokens(tokens);
    }
}


================================================
FILE: tests/compiletest.rs
================================================
#[rustversion::attr(not(nightly), ignore = "requires nightly")]
#[cfg_attr(miri, ignore = "incompatible with miri")]
#[test]
fn ui() {
    let t = trybuild::TestCases::new();
    t.compile_fail("tests/ui/*.rs");
}


================================================
FILE: tests/test.rs
================================================
mod types {
    use inherent::inherent;

    trait Trait {
        fn f<T: ?Sized>(self);
        // A default method
        fn g(&self) {}

        #[rustversion::since(1.75)]
        async fn a(&self);
    }

    pub struct Struct;

    #[inherent]
    impl Trait for Struct {
        pub fn f<T: ?Sized>(self) {}
        pub fn g(&self);

        #[rustversion::since(1.75)]
        pub async fn a(&self) {}
    }
}

#[test]
fn test() {
    // types::Trait is not in scope.
    let s = types::Struct;
    s.g();
    s.f::<str>();
}

#[rustversion::since(1.75)]
#[test]
fn test_async() {
    fn assert_future<T: std::future::Future<Output = ()>>(_: T) {}

    let s = types::Struct;
    assert_future(s.a());
}


================================================
FILE: tests/ui/associated-type.rs
================================================
use inherent::inherent;

pub trait Trait {
    type Assoc;
    fn f() -> Self::Assoc;
}

pub struct Struct;

#[inherent]
impl Trait for Struct {
    type Assoc = ();

    // TODO: https://github.com/dtolnay/inherent/issues/15
    fn f() -> Self::Assoc {}
}

fn main() {}


================================================
FILE: tests/ui/associated-type.stderr
================================================
error[E0223]: ambiguous associated type
  --> tests/ui/associated-type.rs:15:15
   |
15 |     fn f() -> Self::Assoc {}
   |               ^^^^^^^^^^^
   |
help: use fully-qualified syntax
   |
15 -     fn f() -> Self::Assoc {}
15 +     fn f() -> <Struct as Trait>::Assoc {}
   |


================================================
FILE: tests/ui/blanket-impl.rs
================================================
use inherent::inherent;

trait A {
    fn a(&self);
}

#[inherent]
impl<T> A for T {
    fn a(&self) {}
}

fn main() {}


================================================
FILE: tests/ui/blanket-impl.stderr
================================================
error[E0118]: no nominal type found for inherent implementation
 --> tests/ui/blanket-impl.rs:8:1
  |
8 | impl<T> A for T {
  | ^^^^^^^^^^^^^^^ impl requires a nominal type
  |
  = note: either implement a trait on it or create a newtype to wrap it instead


================================================
FILE: tests/ui/not-trait-impl.rs
================================================
use inherent::inherent;

struct Struct;

#[inherent]
impl Struct {
    fn f() {}
}

fn main() {}


================================================
FILE: tests/ui/not-trait-impl.stderr
================================================
error: must be placed on a trait impl
 --> tests/ui/not-trait-impl.rs:5:1
  |
5 | #[inherent]
  | ^^^^^^^^^^^
  |
  = note: this error originates in the attribute macro `inherent` (in Nightly builds, run with -Z macro-backtrace for more info)


================================================
FILE: tests/ui/not-visible.rs
================================================
mod types {
    use inherent::inherent;

    trait Trait {
        fn f();
    }

    pub struct Struct;

    #[inherent]
    impl Trait for Struct {
        fn f() {}
    }
}

fn main() {
    types::Struct::f();
}


================================================
FILE: tests/ui/not-visible.stderr
================================================
error[E0624]: associated function `f` is private
  --> tests/ui/not-visible.rs:17:20
   |
12 |         fn f() {}
   |         ------ private associated function defined here
...
17 |     types::Struct::f();
   |                    ^ private associated function