# Clippy
-[![Clippy Test](https://github.com/rust-lang/rust-clippy/workflows/Clippy%20Test/badge.svg?branch=auto&event=push)](https://github.com/rust-lang/rust-clippy/actions?query=workflow%3A%22Clippy+Test%22+event%3Apush+branch%3Aauto)
+[![Clippy Test](https://github.com/rust-lang/rust-clippy/workflows/Clippy%20Test%20(bors)/badge.svg?branch=auto&event=push)](https://github.com/rust-lang/rust-clippy/actions?query=workflow%3A%22Clippy+Test+(bors)%22+event%3Apush+branch%3Aauto)
[![License: MIT OR Apache-2.0](https://img.shields.io/crates/l/clippy.svg)](#license)
A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code.
-[There are over 500 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html)
+[There are over 550 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html)
Lints are divided into categories, each with a default [lint level](https://doc.rust-lang.org/rustc/lints/levels.html).
You can choose how much Clippy is supposed to ~~annoy~~ help you by changing the lint level by category.
## Usage
-Below are instructions on how to use Clippy as a subcommand, compiled from source
-or in Travis CI.
+Below are instructions on how to use Clippy as a cargo subcommand,
+in projects that do not use cargo, or in Travis CI.
### As a cargo subcommand (`cargo clippy`)
cargo clippy -p example -- --no-deps
```
-### As a rustc replacement (`clippy-driver`)
+### Using `clippy-driver`
-Clippy can also be used in projects that do not use cargo. To do so, you will need to replace
-your `rustc` compilation commands with `clippy-driver`. For example, if your project runs:
-
-```terminal
-rustc --edition 2018 -Cpanic=abort foo.rs
-```
-
-Then, to enable Clippy, you will need to call:
+Clippy can also be used in projects that do not use cargo. To do so, run `clippy-driver`
+with the same arguments you use for `rustc`. For example:
```terminal
clippy-driver --edition 2018 -Cpanic=abort foo.rs
```
-Note that `rustc` will still run, i.e. it will still emit the output files it normally does.
+Note that `clippy-driver` is designed for running Clippy only and should not be used as a general
+replacement for `rustc`. `clippy-driver` may produce artifacts that are not optimized as expected,
+for example.
### Travis CI
## Configuration
-Some lints can be configured in a TOML file named `clippy.toml` or `.clippy.toml`. It contains a basic `variable =
-value` mapping e.g.
-
-```toml
-avoid-breaking-exported-api = false
-blacklisted-names = ["toto", "tata", "titi"]
-cognitive-complexity-threshold = 30
-```
-
-See the [list of lints](https://rust-lang.github.io/rust-clippy/master/index.html) for more information about which
-lints can be configured and the meaning of the variables.
-
-Note that configuration changes will not apply for code that has already been compiled and cached under `./target/`;
-for example, adding a new string to `doc-valid-idents` may still result in Clippy flagging that string. To be sure that
-any configuration changes are applied, you may want to run `cargo clean` and re-compile your crate from scratch.
-
-To deactivate the “for further information visit *lint-link*” message you can
-define the `CLIPPY_DISABLE_DOCS_LINKS` environment variable.
-
### Allowing/denying lints
You can add options to your code to `allow`/`warn`/`deny` Clippy lints:
cargo clippy -- -A clippy::all -W clippy::useless_format -W clippy::...
```
+### Configure the behavior of some lints
+
+Some lints can be configured in a TOML file named `clippy.toml` or `.clippy.toml`. It contains a basic `variable =
+value` mapping e.g.
+
+```toml
+avoid-breaking-exported-api = false
+disallowed-names = ["toto", "tata", "titi"]
+cognitive-complexity-threshold = 30
+```
+
+See the [list of configurable lints](https://rust-lang.github.io/rust-clippy/master/index.html#Configuration),
+the lint descriptions contain the names and meanings of these configuration variables.
+
+> **Note**
+>
+> `clippy.toml` or `.clippy.toml` cannot be used to allow/deny lints.
+
+To deactivate the “for further information visit *lint-link*” message you can
+define the `CLIPPY_DISABLE_DOCS_LINKS` environment variable.
+
### Specifying the minimum supported Rust version
Projects that intend to support old versions of Rust can disable lints pertaining to newer features by
msrv = "1.30.0"
```
-The MSRV can also be specified as an inner attribute, like below.
+Alternatively, the [`rust-version` field](https://doc.rust-lang.org/cargo/reference/manifest.html#the-rust-version-field)
+in the `Cargo.toml` can be used.
+
+```toml
+# Cargo.toml
+rust-version = "1.30"
+```
+
+The MSRV can also be specified as an attribute, like below.
```rust
#![feature(custom_inner_attributes)]
## License
-Copyright 2014-2021 The Rust Project Developers
+Copyright 2014-2022 The Rust Project Developers
Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
[https://www.apache.org/licenses/LICENSE-2.0](https://www.apache.org/licenses/LICENSE-2.0)> or the MIT license