From a4d7011c18eeae7fbb11286822b9519dc9a9325f Mon Sep 17 00:00:00 2001 From: Jonathan <30177086+MonliH@users.noreply.github.com> Date: Sun, 11 Oct 2020 16:28:45 +0000 Subject: [PATCH] Document RUSTFMT environment variable (#4464) * Document RUSTFMT env var * Move documentation up * Apply suggestions from code review Co-authored-by: Caleb Cartwright * Fix accedental removal Co-authored-by: Caleb Cartwright # Conflicts: # README.md --- README.md | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/README.md b/README.md index eb39468d4d145..b3d21e6fb87c7 100644 --- a/README.md +++ b/README.md @@ -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.