Pest Formatter is a tool to format Pest grammar files.

cargo install pest_fmt

Then use the pestfmt command to format your .pest files.

$ pestfmt -h
A formatter tool for pest

Usage: pestfmt [OPTIONS] [FILE]...

Arguments:
  [FILE]...  The file or path to format [default: .]

Options:
  -s, --stdin
  -h, --help     Print help
  -V, --version  Print version

$ pestfmt .

It will find all .pest files in the current directory and format and overwrite them.

Output:

Pest Formatter
-------------------------------------
2 files formatted.

You can use --stdin option to format Pest source code from stdin, it will read from stdin and write to stdout.

cat file.pest | pestfmt --stdin

Add pest_fmt into your Cargo.toml:

$ cargo add pest_fmt

Then use the Formatter struct to format pest grammar.

use pest_fmt::Formatter;

let mut fmt = Formatter::new("a={ASCII_DIGIT}");
let out = fmt.format().unwrap();
println!("{out}");
// a = { ASCII_DIGIT }

https://github.com/pest-parser/pest-ide-tools

Based on MacBook Pro (Apple M1 2020)

format (json.pest)                time:   [89.403 µs 89.632 µs 89.878 µs]
format (grammar.pest)             time:   [1.6018 ms 1.6054 ms 1.6105 ms]

Mozilla Public License 2.0