Clippy welcomes contributions from everyone. There are many ways to contribute to Clippy and the following document
explains how you can contribute and how to get started. If you have any questions about contributing or need help with
-anything, feel free to ask questions on issues or visit the `#clippy` on [Discord].
+anything, feel free to ask questions on issues or visit the `#clippy` on [Zulip].
All contributors are expected to follow the [Rust Code of Conduct].
-* [Getting started](#getting-started)
- * [Finding something to fix/improve](#finding-something-to-fiximprove)
-* [Writing code](#writing-code)
-* [How Clippy works](#how-clippy-works)
-* [Fixing nightly build failures](#fixing-build-failures-caused-by-rust)
-* [Issue and PR Triage](#issue-and-pr-triage)
-* [Bors and Homu](#bors-and-homu)
-* [Contributions](#contributions)
-
-[Discord]: https://discord.gg/rust-lang
+- [Contributing to Clippy](#contributing-to-clippy)
+ - [The Clippy book](#the-clippy-book)
+ - [High level approach](#high-level-approach)
+ - [Finding something to fix/improve](#finding-something-to-fiximprove)
+ - [Getting code-completion for rustc internals to work](#getting-code-completion-for-rustc-internals-to-work)
+ - [IntelliJ Rust](#intellij-rust)
+ - [Rust Analyzer](#rust-analyzer)
+ - [How Clippy works](#how-clippy-works)
+ - [Issue and PR triage](#issue-and-pr-triage)
+ - [Bors and Homu](#bors-and-homu)
+ - [Contributions](#contributions)
+
+[Zulip]: https://rust-lang.zulipchat.com/#narrow/stream/clippy
[Rust Code of Conduct]: https://www.rust-lang.org/policies/code-of-conduct
-## Getting started
+## The Clippy book
+
+If you're new to Clippy and don't know where to start the [Clippy book] includes
+a [developer guide] and is a good place to start your journey.
-High level approach:
+[Clippy book]: https://doc.rust-lang.org/nightly/clippy/index.html
+[developer guide]: https://doc.rust-lang.org/nightly/clippy/development/index.html
+
+## High level approach
1. Find something to fix/improve
2. Change code (likely some file in `clippy_lints/src/`)
-3. Follow the instructions in the [docs for writing lints](doc/adding_lints.md) such as running the `setup-toolchain.sh` script
+3. Follow the instructions in the [Basics docs](book/src/development/basics.md)
+ to get set up
4. Run `cargo test` in the root directory and wiggle code until it passes
5. Open a PR (also can be done after 2. if you run into problems)
-### Finding something to fix/improve
+## Finding something to fix/improve
-All issues on Clippy are mentored, if you want help with a bug just ask
-@Manishearth, @flip1995, @phansch or @yaahc.
+All issues on Clippy are mentored, if you want help simply ask someone from the
+Clippy team directly by mentioning them in the issue or over on [Zulip]. All
+currently active team members can be found
+[here](https://github.com/rust-lang/highfive/blob/master/highfive/configs/rust-lang/rust-clippy.json#L3)
-Some issues are easier than others. The [`good first issue`] label can be used to find the easy issues.
-If you want to work on an issue, please leave a comment so that we can assign it to you!
+Some issues are easier than others. The [`good-first-issue`] label can be used to find the easy
+issues. You can use `@rustbot claim` to assign the issue to yourself.
There are also some abandoned PRs, marked with [`S-inactive-closed`].
Pretty often these PRs are nearly completed and just need some extra steps
[`T-AST`] issues will generally need you to match against a predefined syntax structure.
To figure out how this syntax structure is encoded in the AST, it is recommended to run
-`rustc -Z ast-json` on an example of the structure and compare with the [nodes in the AST docs].
+`rustc -Z unpretty=ast-tree` on an example of the structure and compare with the [nodes in the AST docs].
Usually the lint will end up to be a nested series of matches and ifs, [like so][deep-nesting].
-But we can make it nest-less by using [if_chain] macro, [like this][nest-less].
+But we can make it nest-less by using [let chains], [like this][nest-less].
-[`E-medium`] issues are generally pretty easy too, though it's recommended you work on an E-easy issue first.
-They are mostly classified as [`E-medium`], since they might be somewhat involved code wise,
-but not difficult per-se.
+[`E-medium`] issues are generally pretty easy too, though it's recommended you work on an [`good-first-issue`]
+first. Sometimes they are only somewhat involved code wise, but not difficult per-se.
+Note that [`E-medium`] issues may require some knowledge of Clippy internals or some
+debugging to find the actual problem behind the issue.
[`T-middle`] issues can be more involved and require verifying types. The [`ty`] module contains a
lot of methods that are useful, though one of the most useful would be `expr_ty` (gives the type of
an AST expression). `match_def_path()` in Clippy's `utils` module can also be useful.
-[`good first issue`]: https://github.com/rust-lang/rust-clippy/labels/good%20first%20issue
+[`good-first-issue`]: https://github.com/rust-lang/rust-clippy/labels/good-first-issue
[`S-inactive-closed`]: https://github.com/rust-lang/rust-clippy/pulls?q=is%3Aclosed+label%3AS-inactive-closed
[`T-AST`]: https://github.com/rust-lang/rust-clippy/labels/T-AST
[`T-middle`]: https://github.com/rust-lang/rust-clippy/labels/T-middle
[`E-medium`]: https://github.com/rust-lang/rust-clippy/labels/E-medium
[`ty`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty
[nodes in the AST docs]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_ast/ast/
-[deep-nesting]: https://github.com/rust-lang/rust-clippy/blob/557f6848bd5b7183f55c1e1522a326e9e1df6030/clippy_lints/src/mem_forget.rs#L29-L43
-[if_chain]: https://docs.rs/if_chain/*/if_chain
-[nest-less]: https://github.com/rust-lang/rust-clippy/blob/557f6848bd5b7183f55c1e1522a326e9e1df6030/clippy_lints/src/bit_mask.rs#L124-L150
+[deep-nesting]: https://github.com/rust-lang/rust-clippy/blob/5e4f0922911536f80d9591180fa604229ac13939/clippy_lints/src/mem_forget.rs#L31-L45
+[let chains]: https://github.com/rust-lang/rust/pull/94927
+[nest-less]: https://github.com/rust-lang/rust-clippy/blob/5e4f0922911536f80d9591180fa604229ac13939/clippy_lints/src/bit_mask.rs#L133-L159
+
+## Getting code-completion for rustc internals to work
+
+### IntelliJ Rust
+Unfortunately, [`IntelliJ Rust`][IntelliJ_rust_homepage] does not (yet?) understand how Clippy uses compiler-internals
+using `extern crate` and it also needs to be able to read the source files of the rustc-compiler which are not
+available via a `rustup` component at the time of writing.
+To work around this, you need to have a copy of the [rustc-repo][rustc_repo] available which can be obtained via
+`git clone https://github.com/rust-lang/rust/`.
+Then you can run a `cargo dev` command to automatically make Clippy use the rustc-repo via path-dependencies
+which `IntelliJ Rust` will be able to understand.
+Run `cargo dev setup intellij --repo-path <repo-path>` where `<repo-path>` is a path to the rustc repo
+you just cloned.
+The command will add path-dependencies pointing towards rustc-crates inside the rustc repo to
+Clippy's `Cargo.toml`s and should allow `IntelliJ Rust` to understand most of the types that Clippy uses.
+Just make sure to remove the dependencies again before finally making a pull request!
+
+[rustc_repo]: https://github.com/rust-lang/rust/
+[IntelliJ_rust_homepage]: https://intellij-rust.github.io/
+
+### Rust Analyzer
+For [`rust-analyzer`][ra_homepage] to work correctly make sure that in the `rust-analyzer` configuration you set
+
+```json
+{ "rust-analyzer.rustc.source": "discover" }
+```
-## Writing code
+You should be able to see information on things like `Expr` or `EarlyContext` now if you hover them, also
+a lot more type hints.
-Have a look at the [docs for writing lints][adding_lints] for more details.
+To have `rust-analyzer` also work in the `clippy_dev` and `lintcheck` crates, add the following configuration
-If you want to add a new lint or change existing ones apart from bugfixing, it's
-also a good idea to give the [stability guarantees][rfc_stability] and
-[lint categories][rfc_lint_cats] sections of the [Clippy 1.0 RFC][clippy_rfc] a
-quick read.
+```json
+{
+ "rust-analyzer.linkedProjects": [
+ "./Cargo.toml",
+ "clippy_dev/Cargo.toml",
+ "lintcheck/Cargo.toml",
+ ]
+}
+```
-[adding_lints]: https://github.com/rust-lang/rust-clippy/blob/master/doc/adding_lints.md
-[clippy_rfc]: https://github.com/rust-lang/rfcs/blob/master/text/2476-clippy-uno.md
-[rfc_stability]: https://github.com/rust-lang/rfcs/blob/master/text/2476-clippy-uno.md#stability-guarantees
-[rfc_lint_cats]: https://github.com/rust-lang/rfcs/blob/master/text/2476-clippy-uno.md#lint-audit-and-categories
+[ra_homepage]: https://rust-analyzer.github.io/
## How Clippy works
[early_lint_pass]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/trait.EarlyLintPass.html
[late_lint_pass]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/trait.LateLintPass.html
-## Fixing build failures caused by Rust
-
-Clippy currently gets built with `rustc` of the `rust-lang/rust` `master`
-branch. Most of the times we have to adapt to the changes and only very rarely
-there's an actual bug in Rust.
-
-If you decide to make Clippy work again with a Rust commit that breaks it, you
-have to sync the `rust-lang/rust-clippy` repository with the `subtree` copy of
-Clippy in the `rust-lang/rust` repository.
-
-For general information about `subtree`s in the Rust repository see [Rust's
-`CONTRIBUTING.md`][subtree].
-
-Here is a TL;DR version of the sync process (all of the following commands have
-to be run inside the `rust` directory):
-
-1. Clone the [`rust-lang/rust`] repository
-2. Sync the changes to the rust-copy of Clippy to your Clippy fork:
- ```bash
- # Make sure to change `your-github-name` to your github name in the following command
- git subtree push -P src/tools/clippy git@github.com:your-github-name/rust-clippy sync-from-rust
- ```
- _Note:_ This will directly push to the remote repository. You can also push
- to your local copy by replacing the remote address with `/path/to/rust-clippy`
- directory.
-
- _Note:_ Most of the time you have to create a merge commit in the
- `rust-clippy` repo (this has to be done in the Clippy repo, not in the
- rust-copy of Clippy):
- ```bash
- git fetch origin && git fetch upstream
- git checkout sync-from-rust
- git merge upstream/master
- ```
-3. Open a PR to `rust-lang/rust-clippy` and wait for it to get merged (to
- accelerate the process ping the `@rust-lang/clippy` team in your PR and/or
- ~~annoy~~ ask them in the [Discord] channel.)
-4. Sync the `rust-lang/rust-clippy` master to the rust-copy of Clippy:
- ```bash
- git checkout -b sync-from-clippy
- git subtree pull -P src/tools/clippy https://github.com/rust-lang/rust-clippy master
- ```
-5. Open a PR to [`rust-lang/rust`]
-
-Also, you may want to define remotes, so you don't have to type out the remote
-addresses on every sync. You can do this with the following commands (these
-commands still have to be run inside the `rust` directory):
-
-```bash
-# Set clippy-upstream remote for pulls
-$ git remote add clippy-upstream https://github.com/rust-lang/rust-clippy
-# Make sure to not push to the upstream repo
-$ git remote set-url --push clippy-upstream DISABLED
-# Set clippy-origin remote to your fork for pushes
-$ git remote add clippy-origin git@github.com:your-github-name/rust-clippy
-# Set a local remote
-$ git remote add clippy-local /path/to/rust-clippy
-```
-
-You can then sync with the remote names from above, e.g.:
-
-```bash
-$ git subtree push -P src/tools/clippy clippy-local sync-from-rust
-```
-
-_Note:_ The first time running `git subtree push` a cache has to be built. This
-involves going through the complete Clippy history once. For this you have to
-increase the stack limit though, which you can do with `ulimit -s 60000`. For
-this to work, you will need the fix of `git subtree` available
-[here][gitgitgadget-pr].
-
-[gitgitgadget-pr]: https://github.com/gitgitgadget/git/pull/493
-[subtree]: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#external-dependencies-subtree
-[`rust-lang/rust`]: https://github.com/rust-lang/rust
-
## Issue and PR triage
Clippy is following the [Rust triage procedure][triage] for issues and pull
responding to issues there may not always be enough time to stay on top of it
all.
-Our highest priority is fixing [crashes][l-crash] and [bugs][l-bug]. We don't
+Our highest priority is fixing [crashes][l-crash] and [bugs][l-bug], for example
+an ICE in a popular crate that many other crates depend on. We don't
want Clippy to crash on your code and we want it to be as reliable as the
suggestions from Rust compiler errors.
+We have prioritization labels and a sync-blocker label, which are described below.
+- [P-low][p-low]: Requires attention (fix/response/evaluation) by a team member but isn't urgent.
+- [P-medium][p-medium]: Should be addressed by a team member until the next sync.
+- [P-high][p-high]: Should be immediately addressed and will require an out-of-cycle sync or a backport.
+- [L-sync-blocker][l-sync-blocker]: An issue that "blocks" a sync.
+Or rather: before the sync this should be addressed,
+e.g. by removing a lint again, so it doesn't hit beta/stable.
+
## Bors and Homu
We use a bot powered by [Homu][homu] to help automate testing and landing of pull
commands [here][homu_instructions].
[triage]: https://forge.rust-lang.org/release/triage-procedure.html
-[l-crash]: https://github.com/rust-lang/rust-clippy/labels/L-crash%20%3Aboom%3A
-[l-bug]: https://github.com/rust-lang/rust-clippy/labels/L-bug%20%3Abeetle%3A
+[l-crash]: https://github.com/rust-lang/rust-clippy/labels/L-crash
+[l-bug]: https://github.com/rust-lang/rust-clippy/labels/L-bug
+[p-low]: https://github.com/rust-lang/rust-clippy/labels/P-low
+[p-medium]: https://github.com/rust-lang/rust-clippy/labels/P-medium
+[p-high]: https://github.com/rust-lang/rust-clippy/labels/P-high
+[l-sync-blocker]: https://github.com/rust-lang/rust-clippy/labels/L-sync-blocker
[homu]: https://github.com/rust-lang/homu
-[homu_instructions]: https://buildbot2.rust-lang.org/homu/
-[homu_queue]: https://buildbot2.rust-lang.org/homu/queue/clippy
+[homu_instructions]: https://bors.rust-lang.org/
+[homu_queue]: https://bors.rust-lang.org/queue/clippy
## Contributions
projects / rust.git / blobdiff