mirror of
https://github.com/rust-lang/rust-clippy
synced 2024-12-18 00:53:31 +00:00
f11d993c0f
* master: (58 commits) Rustfmt all the things Don't make decisions on values that don't represent the decision Improving comments. Rustup Added rustfix to the test. Improve span shortening. Added "make_return" and "blockify" convenience methods in Sugg and used them in "needless_bool". Actually check for constants. Fixed potential mistakes with nesting. Added tests. formatting fix Update clippy_lints/src/needless_bool.rs formatting fix Fixing typo in CONTRIBUTING.md Fix breakage due to rust-lang/rust#57651 needless bool lint suggestion is wrapped in brackets if it is an "else" clause of an "if-else" statement Fix automatic suggestion on `use_self`. Remove negative integer literal checks. Fix `implicit_return` false positives. Run rustfmt Fixed breakage due to rust-lang/rust#57489 ...
171 lines
6.2 KiB
Markdown
171 lines
6.2 KiB
Markdown
# Clippy
|
|
|
|
[](https://travis-ci.com/rust-lang/rust-clippy)
|
|
[](https://ci.appveyor.com/project/rust-lang-libs/rust-clippy)
|
|
[](https://crates.io/crates/clippy)
|
|
[](#license)
|
|
|
|
A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code.
|
|
|
|
[There are 292 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html)
|
|
|
|
We have a bunch of lint categories to allow you to choose how much Clippy is supposed to ~~annoy~~ help you:
|
|
|
|
* `clippy::all` (everything that has no false positives)
|
|
* `clippy::pedantic` (everything)
|
|
* `clippy::nursery` (new lints that aren't quite ready yet)
|
|
* `clippy::style` (code that should be written in a more idiomatic way)
|
|
* `clippy::complexity` (code that does something simple but in a complex way)
|
|
* `clippy::perf` (code that can be written in a faster way)
|
|
* `clippy::cargo` (checks against the cargo manifest)
|
|
* **`clippy::correctness`** (code that is just outright wrong or very very useless)
|
|
|
|
More to come, please [file an issue](https://github.com/rust-lang/rust-clippy/issues) if you have ideas!
|
|
|
|
Only the following of those categories are enabled by default:
|
|
|
|
* `clippy::style`
|
|
* `clippy::correctness`
|
|
* `clippy::complexity`
|
|
* `clippy::perf`
|
|
|
|
Other categories need to be enabled in order for their lints to be executed.
|
|
|
|
Table of contents:
|
|
|
|
* [Usage instructions](#usage)
|
|
* [Configuration](#configuration)
|
|
* [License](#license)
|
|
|
|
## Usage
|
|
|
|
Since this is a tool for helping the developer of a library or application
|
|
write better code, it is recommended not to include Clippy as a hard dependency.
|
|
Options include using it as an optional dependency, as a cargo subcommand, or
|
|
as an included feature during build. These options are detailed below.
|
|
|
|
### As a cargo subcommand (`cargo clippy`)
|
|
|
|
One way to use Clippy is by installing Clippy through rustup as a cargo
|
|
subcommand.
|
|
|
|
#### Step 1: Install rustup
|
|
|
|
You can install [rustup](http://rustup.rs/) on supported platforms. This will help
|
|
us install Clippy and its dependencies.
|
|
|
|
If you already have rustup installed, update to ensure you have the latest
|
|
rustup and compiler:
|
|
|
|
```terminal
|
|
rustup update
|
|
```
|
|
|
|
#### Step 2: Install Clippy
|
|
|
|
Once you have rustup and the latest stable release (at least Rust 1.29) installed, run the following command:
|
|
|
|
```terminal
|
|
rustup component add clippy
|
|
```
|
|
If it says that it can't find the `clippy` component, please run `rustup self update`.
|
|
|
|
#### Step 3: Run Clippy
|
|
|
|
Now you can run Clippy by invoking the following command:
|
|
|
|
```terminal
|
|
cargo clippy
|
|
```
|
|
|
|
### Running Clippy from the command line without installing it
|
|
|
|
To have cargo compile your crate with Clippy without Clippy installation
|
|
in your code, you can use:
|
|
|
|
```terminal
|
|
cargo run --bin cargo-clippy --manifest-path=path_to_clippys_Cargo.toml
|
|
```
|
|
|
|
*[Note](https://github.com/rust-lang/rust-clippy/wiki#a-word-of-warning):*
|
|
Be sure that Clippy was compiled with the same version of rustc that cargo invokes here!
|
|
|
|
### Travis CI
|
|
|
|
You can add Clippy to Travis CI in the same way you use it locally:
|
|
|
|
```yml
|
|
language: rust
|
|
rust:
|
|
- stable
|
|
- beta
|
|
before_script:
|
|
- rustup component add clippy
|
|
script:
|
|
- cargo clippy
|
|
# if you want the build job to fail when encountering warnings, use
|
|
- cargo clippy -- -D warnings
|
|
# in order to also check tests and none-default crate features, use
|
|
- cargo clippy --all-targets --all-features -- -D warnings
|
|
- cargo test
|
|
# etc.
|
|
```
|
|
|
|
It might happen that Clippy is not available for a certain nightly release.
|
|
In this case you can try to conditionally install Clippy from the git repo.
|
|
|
|
```yaml
|
|
language: rust
|
|
rust:
|
|
- nightly
|
|
before_script:
|
|
- rustup component add clippy --toolchain=nightly || cargo install --git https://github.com/rust-lang/rust-clippy/ --force clippy
|
|
# etc
|
|
```
|
|
|
|
## Configuration
|
|
|
|
Some lints can be configured in a TOML file named `clippy.toml` or `.clippy.toml`. It contains a basic `variable = value` mapping eg.
|
|
|
|
```toml
|
|
blacklisted-names = ["toto", "tata", "titi"]
|
|
cyclomatic-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.
|
|
|
|
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:
|
|
|
|
* the whole set of `Warn` lints using the `clippy` lint group (`#![deny(clippy::all)]`)
|
|
|
|
* all lints using both the `clippy` and `clippy::pedantic` lint groups (`#![deny(clippy::all)]`,
|
|
`#![deny(clippy::pedantic)]`). Note that `clippy::pedantic` contains some very aggressive
|
|
lints prone to false positives.
|
|
|
|
* only some lints (`#![deny(clippy::single_match, clippy::box_vec)]`, etc)
|
|
|
|
* `allow`/`warn`/`deny` can be limited to a single function or module using `#[allow(...)]`, etc
|
|
|
|
Note: `deny` produces errors instead of warnings.
|
|
|
|
If you do not want to include your lint levels in your code, you can globally enable/disable lints by passing extra flags to Clippy during the run: `cargo clippy -- -A clippy::lint_name` will run Clippy with `lint_name` disabled and `cargo clippy -- -W clippy::lint_name` will run it with that enabled. This also works with lint groups. For example you can run Clippy with warnings for all lints enabled: `cargo clippy -- -W clippy::pedantic`
|
|
|
|
## Contributing
|
|
|
|
If you want to contribute to Clippy, you can find more information in [CONTRIBUTING.md](https://github.com/rust-lang/rust-clippy/blob/master/CONTRIBUTING.md).
|
|
|
|
## License
|
|
|
|
Copyright 2014-2019 The Rust Project Developers
|
|
|
|
Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
|
http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
|
<LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
|
option. All files in the project carrying such notice may not be
|
|
copied, modified, or distributed except according to those terms.
|