X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=README.md;h=0eb7c4b266a9f3a529e1b3c555ac2bf1dee974c1;hb=fe26182281f3f43e2dd237e9c0335da9059c9959;hp=ab44db694835faac056a6a3e47060a0e0518821d;hpb=7d1609dce356b9b603702f1ba0011f2fee949787;p=rust.git diff --git a/README.md b/README.md index ab44db69483..0eb7c4b266a 100644 --- a/README.md +++ b/README.md @@ -1,267 +1,306 @@ -# Clippy +# The Rust Programming Language -[![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) +This is the main source code repository for [Rust]. It contains the compiler, +standard library, and documentation. -A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code. +[Rust]: https://www.rust-lang.org/ -[There are over 550 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html) +**Note: this README is for _users_ rather than _contributors_.** +If you wish to _contribute_ to the compiler, you should read +[CONTRIBUTING.md](CONTRIBUTING.md) instead. -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. +## Quick Start -| Category | Description | Default level | -| --------------------- | ----------------------------------------------------------------------------------- | ------------- | -| `clippy::all` | all lints that are on by default (correctness, suspicious, style, complexity, perf) | **warn/deny** | -| `clippy::correctness` | code that is outright wrong or useless | **deny** | -| `clippy::suspicious` | code that is most likely wrong or useless | **warn** | -| `clippy::style` | code that should be written in a more idiomatic way | **warn** | -| `clippy::complexity` | code that does something simple but in a complex way | **warn** | -| `clippy::perf` | code that can be written to run faster | **warn** | -| `clippy::pedantic` | lints which are rather strict or have occasional false positives | allow | -| `clippy::nursery` | new lints that are still under development | allow | -| `clippy::cargo` | lints for the cargo manifest | allow | +Read ["Installation"] from [The Book]. -More to come, please [file an issue](https://github.com/rust-lang/rust-clippy/issues) if you have ideas! +["Installation"]: https://doc.rust-lang.org/book/ch01-01-installation.html +[The Book]: https://doc.rust-lang.org/book/index.html -The [lint list](https://rust-lang.github.io/rust-clippy/master/index.html) also contains "restriction lints", which are -for things which are usually not considered "bad", but may be useful to turn on in specific cases. These should be used -very selectively, if at all. +## Installing from Source -Table of contents: +The Rust build system uses a Python script called `x.py` to build the compiler, +which manages the bootstrapping process. It lives at the root of the project. -* [Usage instructions](#usage) -* [Configuration](#configuration) -* [Contributing](#contributing) -* [License](#license) +The `x.py` command can be run directly on most Unix systems in the following +format: -## Usage +```sh +./x.py [flags] +``` -Below are instructions on how to use Clippy as a cargo subcommand, -in projects that do not use cargo, or in Travis CI. +This is how the documentation and examples assume you are running `x.py`. +Some alternative ways are: -### As a cargo subcommand (`cargo clippy`) +```sh +# On a Unix shell if you don't have the necessary `python3` command +./x [flags] -One way to use Clippy is by installing Clippy through rustup as a cargo -subcommand. +# On the Windows Command Prompt (if .py files are configured to run Python) +x.py [flags] -#### Step 1: Install Rustup +# You can also run Python yourself, e.g.: +python x.py [flags] +``` -You can install [Rustup](https://rustup.rs/) on supported platforms. This will help -us install Clippy and its dependencies. +More information about `x.py` can be found by running it with the `--help` flag +or reading the [rustc dev guide][rustcguidebuild]. -If you already have Rustup installed, update to ensure you have the latest -Rustup and compiler: +[gettingstarted]: https://rustc-dev-guide.rust-lang.org/getting-started.html +[rustcguidebuild]: https://rustc-dev-guide.rust-lang.org/building/how-to-build-and-run.html -```terminal -rustup update -``` +### Dependencies -#### Step 2: Install Clippy +Make sure you have installed the dependencies: -Once you have rustup and the latest stable release (at least Rust 1.29) installed, run the following command: +* `python` 3 or 2.7 +* `git` +* A C compiler (when building for the host, `cc` is enough; cross-compiling may + need additional compilers) +* `curl` (not needed on Windows) +* `pkg-config` if you are compiling on Linux and targeting Linux +* `libiconv` (already included with glibc on Debian-based distros) -```terminal -rustup component add clippy -``` -If it says that it can't find the `clippy` component, please run `rustup self update`. +To build Cargo, you'll also need OpenSSL (`libssl-dev` or `openssl-devel` on +most Unix distros). -#### Step 3: Run Clippy +If building LLVM from source, you'll need additional tools: -Now you can run Clippy by invoking the following command: +* `g++`, `clang++`, or MSVC with versions listed on + [LLVM's documentation](https://llvm.org/docs/GettingStarted.html#host-c-toolchain-both-compiler-and-standard-library) +* `ninja`, or GNU `make` 3.81 or later (Ninja is recommended, especially on + Windows) +* `cmake` 3.13.4 or later +* `libstdc++-static` may be required on some Linux distributions such as Fedora + and Ubuntu -```terminal -cargo clippy -``` +On tier 1 or tier 2 with host tools platforms, you can also choose to download +LLVM by setting `llvm.download-ci-llvm = true`. +Otherwise, you'll need LLVM installed and `llvm-config` in your path. +See [the rustc-dev-guide for more info][sysllvm]. -#### Automatically applying Clippy suggestions +[sysllvm]: https://rustc-dev-guide.rust-lang.org/building/new-target.html#using-pre-built-llvm -Clippy can automatically apply some lint suggestions, just like the compiler. -```terminal -cargo clippy --fix -``` +### Building on a Unix-like system -#### Workspaces +1. Clone the [source] with `git`: -All the usual workspace options should work with Clippy. For example the following command -will run Clippy on the `example` crate: + ```sh + git clone https://github.com/rust-lang/rust.git + cd rust + ``` -```terminal -cargo clippy -p example -``` +[source]: https://github.com/rust-lang/rust -As with `cargo check`, this includes dependencies that are members of the workspace, like path dependencies. -If you want to run Clippy **only** on the given crate, use the `--no-deps` option like this: +2. Configure the build settings: -```terminal -cargo clippy -p example -- --no-deps -``` + The Rust build system uses a file named `config.toml` in the root of the + source tree to determine various configuration settings for the build. + Set up the defaults intended for distros to get started. You can see a full + list of options in `config.toml.example`. -### Using `clippy-driver` + ```sh + printf 'profile = "user" \nchangelog-seen = 2 \n' > config.toml + ``` -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: + If you plan to use `x.py install` to create an installation, it is + recommended that you set the `prefix` value in the `[install]` section to a + directory. -```terminal -clippy-driver --edition 2018 -Cpanic=abort foo.rs -``` +3. Build and install: + + ```sh + ./x.py build && ./x.py install + ``` + + When complete, `./x.py install` will place several programs into + `$PREFIX/bin`: `rustc`, the Rust compiler, and `rustdoc`, the + API-documentation tool. If you've set `profile = "user"` or + `build.extended = true`, it will also include [Cargo], Rust's package + manager. + +[Cargo]: https://github.com/rust-lang/cargo -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 - -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 non-default crate features, use - - cargo clippy --all-targets --all-features -- -D warnings - - cargo test - # etc. +### Building on Windows + +On Windows, we suggest using [winget] to install dependencies by running the +following in a terminal: + +```powershell +winget install -e Python.Python.3 +winget install -e Kitware.CMake +winget install -e Git.Git ``` -Note that adding `-D warnings` will cause your build to fail if **any** warnings are found in your code. -That includes warnings found by rustc (e.g. `dead_code`, etc.). If you want to avoid this and only cause -an error for Clippy warnings, use `#![deny(clippy::all)]` in your code or `-D clippy::all` on the command -line. (You can swap `clippy::all` with the specific lint category you are targeting.) +Then edit your system's `PATH` variable and add: `C:\Program Files\CMake\bin`. +See +[this guide on editing the system `PATH`](https://www.java.com/en/download/help/path.html) +from the Java documentation. -## Configuration +[winget]: https://github.com/microsoft/winget-cli -### Allowing/denying lints +There are two prominent ABIs in use on Windows: the native (MSVC) ABI used by +Visual Studio and the GNU ABI used by the GCC toolchain. Which version of Rust +you need depends largely on what C/C++ libraries you want to interoperate with. +Use the MSVC build of Rust to interop with software produced by Visual Studio +and the GNU build to interop with GNU software built using the MinGW/MSYS2 +toolchain. -You can add options to your code to `allow`/`warn`/`deny` Clippy lints: +#### MinGW -* the whole set of `Warn` lints using the `clippy` lint group (`#![deny(clippy::all)]`). - Note that `rustc` has additional [lint groups](https://doc.rust-lang.org/rustc/lints/groups.html). +[MSYS2][msys2] can be used to easily build Rust on Windows: -* 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. +[msys2]: https://www.msys2.org/ -* only some lints (`#![deny(clippy::single_match, clippy::box_vec)]`, etc.) +1. Download the latest [MSYS2 installer][msys2] and go through the installer. -* `allow`/`warn`/`deny` can be limited to a single function or module using `#[allow(...)]`, etc. +2. Run `mingw32_shell.bat` or `mingw64_shell.bat` from the MSYS2 installation + directory (e.g. `C:\msys64`), depending on whether you want 32-bit or 64-bit + Rust. (As of the latest version of MSYS2 you have to run `msys2_shell.cmd + -mingw32` or `msys2_shell.cmd -mingw64` from the command line instead.) -Note: `allow` means to suppress the lint for your code. With `warn` the lint -will only emit a warning, while with `deny` the lint will emit an error, when -triggering for your code. An error causes clippy to exit with an error code, so -is useful in scripts like CI/CD. +3. From this terminal, install the required tools: -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: + ```sh + # Update package mirrors (may be needed if you have a fresh install of MSYS2) + pacman -Sy pacman-mirrors -To allow `lint_name`, run + # Install build tools needed for Rust. If you're building a 32-bit compiler, + # then replace "x86_64" below with "i686". If you've already got Git, Python, + # or CMake installed and in PATH you can remove them from this list. + # Note that it is important that you do **not** use the 'python2', 'cmake', + # and 'ninja' packages from the 'msys2' subsystem. + # The build has historically been known to fail with these packages. + pacman -S git \ + make \ + diffutils \ + tar \ + mingw-w64-x86_64-python \ + mingw-w64-x86_64-cmake \ + mingw-w64-x86_64-gcc \ + mingw-w64-x86_64-ninja + ``` -```terminal -cargo clippy -- -A clippy::lint_name -``` +4. Navigate to Rust's source code (or clone it), then build it: -And to warn on `lint_name`, run + ```sh + ./x.py build && ./x.py install + ``` -```terminal -cargo clippy -- -W clippy::lint_name -``` +#### MSVC -This also works with lint groups. For example, you -can run Clippy with warnings for all lints enabled: -```terminal -cargo clippy -- -W clippy::pedantic -``` +MSVC builds of Rust additionally require an installation of Visual Studio 2017 +(or later) so `rustc` can use its linker. The simplest way is to get +[Visual Studio], check the "C++ build tools" and "Windows 10 SDK" workload. -If you care only about a single lint, you can allow all others and then explicitly warn on -the lint(s) you are interested in: -```terminal -cargo clippy -- -A clippy::all -W clippy::useless_format -W clippy::... -``` +[Visual Studio]: https://visualstudio.microsoft.com/downloads/ -### Configure the behavior of some lints +(If you're installing CMake yourself, be careful that "C++ CMake tools for +Windows" doesn't get included under "Individual components".) -Some lints can be configured in a TOML file named `clippy.toml` or `.clippy.toml`. It contains a basic `variable = -value` mapping e.g. +With these dependencies installed, you can build the compiler in a `cmd.exe` +shell with: -```toml -avoid-breaking-exported-api = false -disallowed-names = ["toto", "tata", "titi"] +```sh +python x.py build ``` -The [table of configurations](https://doc.rust-lang.org/nightly/clippy/lint_configuration.html) -contains all config values, their default, and a list of lints they affect. -Each [configurable lint](https://rust-lang.github.io/rust-clippy/master/index.html#Configuration) -, also contains information about these values. - -For configurations that are a list type with default values such as -[disallowed-names](https://rust-lang.github.io/rust-clippy/master/index.html#disallowed_names), -you can use the unique value `".."` to extend the default values instead of replacing them. +Right now, building Rust only works with some known versions of Visual Studio. +If you have a more recent version installed and the build system doesn't +understand, you may need to force rustbuild to use an older version. +This can be done by manually calling the appropriate vcvars file before running +the bootstrap. -```toml -# default of disallowed-names is ["foo", "baz", "quux"] -disallowed-names = ["bar", ".."] # -> ["bar", "foo", "baz", "quux"] +```batch +CALL "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat" +python x.py build ``` -> **Note** -> -> `clippy.toml` or `.clippy.toml` cannot be used to allow/deny lints. +#### Specifying an ABI -To deactivate the “for further information visit *lint-link*” message you can -define the `CLIPPY_DISABLE_DOCS_LINKS` environment variable. +Each specific ABI can also be used from either environment (for example, using +the GNU ABI in PowerShell) by using an explicit build triple. The available +Windows build triples are: +- GNU ABI (using GCC) + - `i686-pc-windows-gnu` + - `x86_64-pc-windows-gnu` +- The MSVC ABI + - `i686-pc-windows-msvc` + - `x86_64-pc-windows-msvc` -### Specifying the minimum supported Rust version +The build triple can be specified by either specifying `--build=` when +invoking `x.py` commands, or by creating a `config.toml` file (as described in +[Installing from Source](#installing-from-source)), and modifying the `build` +option under the `[build]` section. -Projects that intend to support old versions of Rust can disable lints pertaining to newer features by -specifying the minimum supported Rust version (MSRV) in the clippy configuration file. +### Configure and Make -```toml -msrv = "1.30.0" +While it's not the recommended build system, this project also provides a +configure script and makefile (the latter of which just invokes `x.py`). + +```sh +./configure +make && sudo make install ``` -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. +`configure` generates a `config.toml` which can also be used with normal `x.py` +invocations. + +## Building Documentation + +If you'd like to build the documentation, it's almost the same: -```toml -# Cargo.toml -rust-version = "1.30" +```sh +./x.py doc ``` -The MSRV can also be specified as an attribute, like below. +The generated documentation will appear under `doc` in the `build` directory for +the ABI used. That is, if the ABI was `x86_64-pc-windows-msvc`, the directory +will be `build\x86_64-pc-windows-msvc\doc`. -```rust -#![feature(custom_inner_attributes)] -#![clippy::msrv = "1.30.0"] +## Notes -fn main() { - ... -} -``` +Since the Rust compiler is written in Rust, it must be built by a precompiled +"snapshot" version of itself (made in an earlier stage of development). +As such, source builds require an Internet connection to fetch snapshots, and an +OS that can execute the available snapshot binaries. + +See https://doc.rust-lang.org/nightly/rustc/platform-support.html for a list of +supported platforms. +Only "host tools" platforms have a pre-compiled snapshot binary available; to +compile for a platform without host tools you must cross-compile. -You can also omit the patch version when specifying the MSRV, so `msrv = 1.30` -is equivalent to `msrv = 1.30.0`. +You may find that other platforms work, but these are our officially supported +build environments that are most likely to work. -Note: `custom_inner_attributes` is an unstable feature, so it has to be enabled explicitly. +## Getting Help -Lints that recognize this configuration option can be found [here](https://rust-lang.github.io/rust-clippy/master/index.html#msrv) +See https://www.rust-lang.org/community for a list of chat platforms and forums. ## 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). +See [CONTRIBUTING.md](CONTRIBUTING.md). ## License -Copyright 2014-2022 The Rust Project Developers +Rust is primarily distributed under the terms of both the MIT license and the +Apache License (Version 2.0), with portions covered by various BSD-like +licenses. + +See [LICENSE-APACHE](LICENSE-APACHE), [LICENSE-MIT](LICENSE-MIT), and +[COPYRIGHT](COPYRIGHT) for details. + +## Trademark + +[The Rust Foundation][rust-foundation] owns and protects the Rust and Cargo +trademarks and logos (the "Rust Trademarks"). + +If you want to use these names or brands, please read the +[media guide][media-guide]. + +Third-party logos may be subject to third-party copyrights and trademarks. See +[Licenses][policies-licenses] for details. -Licensed under the Apache License, Version 2.0 or the MIT license -, at your -option. Files in the project may not be -copied, modified, or distributed except according to those terms. +[rust-foundation]: https://foundation.rust-lang.org/ +[media-guide]: https://foundation.rust-lang.org/policies/logo-policy-and-media-guide/ +[policies-licenses]: https://www.rust-lang.org/policies/licenses