-# rustfmt [](https://travis-ci.org/rust-lang-nursery/rustfmt) [](https://ci.appveyor.com/api/projects/status/github/rust-lang-nursery/rustfmt)
+# rustfmt [](https://travis-ci.org/rust-lang-nursery/rustfmt) [](https://ci.appveyor.com/project/nrc/rustfmt) [](https://crates.io/crates/rustfmt-nightly)
A tool for formatting Rust code according to style guidelines.
## Quick start
-You must be using the latest nightly compiler toolchain.
+Currently, you can use `rustfmt` on nightly and beta. Rust 1.24 stable will work,
+but we're not quite there yet!
To install:
```
-cargo install rustfmt-nightly
+rustup component add rustfmt-preview --toolchain=nightly
```
+If `nightly` is your default toolchain, you can leave the `--toolchain` off.
+
to run on a cargo project in the current working directory:
```
-cargo fmt
+cargo +nightly fmt
```
-## Installation
-
-```
-cargo install rustfmt-nightly
-```
+If `nightly` is your default toolchain, you can leave off the `+nightly`.
-or if you're using [Rustup](https://www.rustup.rs/)
+## Installation
```
-rustup update
-rustup run nightly cargo install rustfmt-nightly
+rustup component add rustfmt-preview --toolchain=nightly
```
If you don't have a nightly toolchain, you can add it using rustup:
If you choose not to do that you'll have to run rustfmt using `rustup run ...`
or by adding `+nightly` to the cargo invocation.
-Usually cargo-fmt, which enables usage of Cargo subcommand `cargo fmt`, is
-installed alongside rustfmt. To only install rustfmt run
-
-```
-cargo install --no-default-features rustfmt-nightly
-```
## Installing from source
To install from source, first checkout to the tag or branch you want to install, then issue
binary and library targets of your crate.
You'll probably want to specify the write mode. Currently, there are modes for
-diff, replace, overwrite, display, coverage, and checkstyle.
+`diff`, `replace`, `overwrite`, `display`, `coverage`, `checkstyle`, and `plain`.
-* `replace` Is the default and overwrites the original files after creating backups of the files.
-* `overwrite` Overwrites the original files _without_ creating backups.
+* `overwrite` Is the default and overwrites the original files _without_ creating backups.
+* `replace` Overwrites the original files after creating backups of the files.
* `display` Will print the formatted files to stdout.
+* `plain` Also writes to stdout, but with no metadata.
* `diff` Will print a diff between the original files and formatted files to stdout.
Will also exit with an error code if there are any differences.
* `checkstyle` Will output the lines that need to be corrected as a checkstyle XML file,
The write mode can be set by passing the `--write-mode` flag on
the command line. For example `rustfmt --write-mode=display src/filename.rs`
-`cargo fmt` uses `--write-mode=replace` by default.
+`cargo fmt` uses `--write-mode=overwrite` by default.
If you want to restrict reformatting to specific sets of lines, you can
use the `--file-lines` option. Its argument is a JSON array of objects
If `rustfmt` successfully reformatted the code it will exit with `0` exit
status. Exit status `1` signals some unexpected error, like an unknown option or
a failure to read a file. Exit status `2` is returned if there are syntax errors
-in the input files. `rustfmt` can't format syntatically invalid code. Finally,
+in the input files. `rustfmt` can't format syntactically invalid code. Finally,
exit status `3` is returned if there are some issues which can't be resolved
automatically. For example, if you have a very long comment line `rustfmt`
doesn't split it. Instead it prints a warning and exits with `3`.
rustfmt to exit with an error code if the input is not formatted correctly.
It will also print any found differences.
-(These instructions use the Syntex version of Rustfmt. If you want to use the
-nightly version replace `install rustfmt` with `install rustfmt-nightly`,
-however you must then only run this with the nightly toolchain).
+(These instructions use the nightly version of Rustfmt. If you want to use the
+Syntex version replace `install rustfmt-nightly` with `install rustfmt`).
A minimal Travis setup could look like this:
cache: cargo
before_script:
- export PATH="$PATH:$HOME/.cargo/bin"
-- which rustfmt || cargo install rustfmt
+- which rustfmt || cargo install rustfmt-nightly
script:
- cargo fmt -- --write-mode=diff
- cargo build
visual style previews, [Configurations.md](Configurations.md).
By default, Rustfmt uses a style which conforms to the [Rust style guide][style
-guide]. For details that have not yet been formalized through the [style RFC
-process][fmt rfcs], we try to adhere to a style similar to that used in the
-[Rust repo][rust].
+guide] that has been formalized through the [style RFC
+process][fmt rfcs].
-If there are styling choices you don't agree with, we are usually happy to add
-options covering different styles. File an issue, or even better, submit a PR.
+Configuration options are either stable or unstable. Stable options can always
+be used, while unstable ones are only available on a nightly toolchain, and opt-in.
+See [Configurations.md](Configurations.md) for details.
## Tips
```
* 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.
+ rustfmt. You can generate a file containing the default configuration with
+ `rustfmt --dump-default-config 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.
+* If you get an error like `error while loading shared libraries` while starting
+ up rustfmt you should try the following:
+
+ On Linux:
+
+ ```
+ export LD_LIBRARY_PATH=$(rustc --print sysroot)/lib:$LD_LIBRARY_PATH
+ ```
+
+ On MacOS:
+
+ ```
+ export DYLD_LIBRARY_PATH=$(rustc --print sysroot)/lib:$DYLD_LIBRARY_PATH
+ ```
+
+ On Windows (Git Bash/Mingw):
+
+ ```
+ export PATH=$(rustc --print sysroot)/lib/rustlib/x86_64-pc-windows-gnu/lib/:$PATH
+ ```
+
+ (Substitute `x86_64` by `i686` and `gnu` by `msvc` depending on which version of rustc was used to install rustfmt).
## License
projects / rust.git / blobdiff