commit | cc5521d9b2fff696a852454dd2aa89e7942464dd | [log] [tgz] |
---|---|---|
author | David Bar-On <61089727+davidBar-On@users.noreply.github.com> | Sat Oct 23 21:58:25 2021 +0300 |
committer | GitHub <noreply@github.com> | Sat Oct 23 13:58:25 2021 -0500 |
tree | 8dd7ab742e1223326eb52f0cb925e43c8cb438fa | |
parent | 1546005ff56a405db529d8dd0935cf606fbe7c9c [diff] |
Fix for issue 4689 - indentation on multiline single generic bound (#4730)
A tool for formatting Rust code according to style guidelines.
If you‘d like to help out (and you should, it’s a fun project!), see Contributing.md and our Code of Conduct.
You can use rustfmt in Travis CI builds. We provide a minimal Travis CI configuration (see here) and verify its status using another repository. The status of that repository's build is reported by the “travis example” badge above.
You can run rustfmt
with Rust 1.24 and above.
To install:
rustup component add rustfmt
To run on a cargo project in the current working directory:
cargo fmt
For the latest and greatest rustfmt
, nightly is required.
To install:
rustup component add rustfmt --toolchain nightly
To run on a cargo project in the current working directory:
cargo +nightly fmt
To install from source (nightly required), first checkout to the tag or branch for the version of rustfmt you want.
The easiest way to install is via cargo make
cargo make install
Alternatively, you can run cargo install
directly as long as you set the required environment variables and features.
export CFG_RELEASE=nightly export CFG_RELEASE_CHANNEL=nightly cargo install --path . --force --locked --features rustfmt,cargo-fmt
(Windows users can use set
to specify the environment variable values)
This will install rustfmt
in your ~/.cargo/bin
. Make sure to add the ~/.cargo/bin
directory to your PATH variable.
Please use rustfmt --help
to see information about available arguments.
cargo fmt
The easiest way to run rustfmt against a project is with cargo fmt
. cargo fmt
works on both single-crate projects and cargo workspaces. Please see cargo fmt --help
for usage information.
You can specify the path to your own rustfmt
binary for cargo to use by setting theRUSTFMT
environment variable. This was added in v1.4.22, so you must have this version or newer to leverage this feature (cargo fmt --version
)
rustfmt
directlyTo format individual files or arbitrary codes from stdin, the rustfmt
binary should be used. Some examples follow:
rustfmt lib.rs main.rs
will format “lib.rs” and “main.rs” in placerustfmt
will read a code from stdin and write formatting to stdoutecho "fn main() {}" | rustfmt
would emit “fn main() {}”.For more information, including arguments and emit options, see rustfmt --help
.
When running with --check
, Rustfmt will exit with 0
if Rustfmt would not make any formatting changes to the input, and 1
if Rustfmt would make changes.
In other modes, Rustfmt will exit with 1
if there was some error during formatting (for example a parsing or internal error) and 0
if formatting completed without error (whether or not changes were made).
Rustfmt is designed to be very configurable. You can create a TOML file called rustfmt.toml
or .rustfmt.toml
, place it in the project or any other parent directory and it will apply the options in that file. See the config website for all available options.
By default, Rustfmt uses a style which conforms to the Rust style guide that has been formalized through the style RFC process.
Configuration options are either stable or unstable. Stable options can always be used on any channel. Unstable options are always available on nightly, but can only be used on stable and beta with an explicit opt-in (starting in Rustfmt v2.0).
Unstable options are not available on stable/beta with Rustfmt v1.x.
See the configuration documentation on the Rustfmt GitHub page for details (look for the unstable_features
section).
On an invocation rustfmt lib.rs
, rustfmt 1.x would format both “lib.rs” and any out-of-file submodules referenced in “lib.rs”, unless the skip_children
configuration option was true.
With rustfmt 2.x, this behavior requires the --recursive
flag (#3587). By default, out-of-file submodules of given files are not formatted.
Note that this only applies to the rustfmt
binary, and does not impact cargo fmt
.
Rustfmt 1.x uses only the configuration options declared in the rustfmt configuration file nearest the directory rustfmt
is invoked.
Rustfmt 2.x merges configuration options from all configuration files in all parent directories, with configuration files nearer the current directory having priority.
Please see Configurations for more information and #3881 for the motivating issue.
Rustfmt is able to pick up the edition used by reading the Cargo.toml
file if executed through the Cargo's formatting tool cargo fmt
. Otherwise, the edition needs to be specified in rustfmt.toml
, e.g., with edition = "2018"
.
Rustfmt tries to work on as much Rust code as possible. Sometimes, the code doesn‘t even need to compile! However, there are some things that Rustfmt can’t do or can't do well. The following list enumerates such limitations:
To keep your code base consistently formatted, it can be helpful to fail the CI build when a pull request contains unformatted code. Using --check
instructs rustfmt to exit with an error code if the input is not formatted correctly. It will also print any found differences. (Older versions of Rustfmt don't support --check
, use --write-mode diff
).
A minimal Travis setup could look like this (requires Rust 1.31.0 or greater):
language: rust before_script: - rustup component add rustfmt script: - cargo build - cargo test - cargo fmt -- --check
See this blog post for more info.
We recommend using cargo make when working with the rustfmt codebase.
You can alternatively use cargo
directly, but you'll have to set the CFG_RELEASE
and CFG_RELEASE_CHANNEL
environment variables and also provide the corresponding features.
For example:
export CFG_RELEASE=1.45.0-nightly export CFG_RELEASE_CHANNEL=nightly
(Windows users can use set
to specify the environment variable values)
To build with cargo make
:
cargo make build
Or alternatively with cargo
directly:
cargo build --all-features # or CFG_RELEASE_CHANNEL=nightly CFG_RELEASE=1.45.0-nightly cargo build --all-features
To run tests with cargo make
:
cargo make test
Or alternatively with cargo
directly:
cargo test --all-features # or CFG_RELEASE_CHANNEL=nightly CFG_RELEASE=1.45.0-nightly cargo test --all-features
To run rustfmt after this, use cargo run --bin rustfmt -- filename
. See the notes above on running rustfmt.
For things you do not want rustfmt to mangle, use #[rustfmt::skip]
To prevent rustfmt from formatting a macro or an attribute, use #[rustfmt::skip::macros(target_macro_name)]
or #[rustfmt::skip::attributes(target_attribute_name)]
Example:
#![rustfmt::skip::attributes(custom_attribute)] #[custom_attribute(formatting , here , should , be , Skipped)] #[rustfmt::skip::macros(html)] fn main() { let macro_result1 = html! { <div> Hello</div> }.to_string();
When you run rustfmt, place a file named rustfmt.toml
or .rustfmt.toml
in target file directory or its parents to override the default settings of rustfmt. You can generate a file containing the default configuration with rustfmt --print-config default rustfmt.toml
and customize as needed.
After successful compilation, a rustfmt
executable can be found in the target directory.
If you're having issues compiling Rustfmt (or compile errors when trying to install), make sure you have the most recent version of Rust installed.
You can change the way rustfmt emits the changes with the --emit flag:
Example:
cargo fmt -- --emit files
Options:
Flag | Description | Nightly Only |
---|---|---|
files | overwrites output to files | No |
stdout | writes output to stdout | No |
checkstyle | emits in a checkstyle format | Yes |
json | emits diffs in a json format | Yes |
Rustfmt is distributed under the terms of both the MIT license and the Apache License (Version 2.0).
See LICENSE-APACHE and LICENSE-MIT for details.