diff --git a/README.md b/README.md index 9c7a1c4bc34..b3d21e6fb87 100644 --- a/README.md +++ b/README.md @@ -47,7 +47,7 @@ cargo +nightly fmt ## Limitations -Rustfmt tries to work on as much Rust code as possible, sometimes, the code +Rustfmt tries to work on as much Rust code as possible. Sometimes, the code doesn't even need to compile! As we approach a 1.0 release we are also looking to limit areas of instability; in particular, post-1.0, the formatting of most code should not change as Rustfmt improves. However, there are some things that @@ -102,6 +102,25 @@ read data from stdin. Alternatively, you can use `cargo fmt` to format all binary and library targets of your crate. You can run `rustfmt --help` for information about available arguments. +The easiest way to run rustfmt against a project is with `cargo fmt`. `cargo fmt` works on both +single-crate projects and [cargo workspaces](https://doc.rust-lang.org/book/ch14-03-cargo-workspaces.html). +Please see `cargo fmt --help` for usage information. + +You can specify the path to your own `rustfmt` binary for cargo to use by setting the`RUSTFMT` +environment variable. This was added in v1.4.22, so you must have this version or newer to leverage this feature (`cargo fmt --version`) + +### Running `rustfmt` directly + +To 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 place +- `rustfmt` will read a code from stdin and write formatting to stdout + - `echo "fn main() {}" | rustfmt` would emit "fn main() {}". + +For more information, including arguments and emit options, see `rustfmt --help`. + +### Verifying code is formatted 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. @@ -129,7 +148,7 @@ 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 1.24.0 or greater): +A minimal Travis setup could look like this (requires Rust 1.31.0 or greater): ```yaml language: rust