tidy

Prettier's style, at native speed.

tidy is a code formatter written in Rust. It prints what Prettier prints, for every language below, from one native binary. No Node required, but there's a Node binding if you want one.

It's fast. On a 12,000-file corpus of every language but XML, tidy checks everything in 280 ms. bun fmt takes 569 ms, oxfmt 1.2 s, and Prettier 18.5 s.

Matches Prettier: 100% of 3,906 JavaScript files and 3,308 of 3,309 TypeScript files in the bench corpus (with JSDoc formatting off)
Formats the code inside your code: styles and scripts in HTML and Vue, Markdown code blocks and front matter, CSS, GraphQL, HTML and Markdown in JS templates
Reads tidy.json, tidy.jsonc or tidy.toml, plus .editorconfig
Stable JS and TS output: where Prettier's output would change on its next run, tidy prints where it settles, so --check stays green in CI

Languages

Language	Style
JavaScript, TypeScript, JSX	Prettier
HTML, Vue, Handlebars, MJML	Prettier
CSS, SCSS, Less	Prettier
JSON, JSONC, JSON5	Prettier
YAML, GraphQL, Markdown	Prettier
XML, SVG	`@prettier/plugin-xml`
TOML	taplo
Dockerfiles	dprint-plugin-dockerfile
INI, `.editorconfig`, `.npmrc`, `.gitconfig`	`prettier-plugin-ini`

Install

Nothing is published yet. For now, build it from a clone of this repo:

$ cargo install --path crates/tidy_cli

Usage

# print one file, formatted
$ tidy index.html

# list the files that aren't formatted; exits 1 if any
$ tidy src --check

# rewrite everything in place
$ tidy . --write

Without paths, tidy reads stdin. Run tidy --help for every flag.

Config

Each file uses the nearest tidy.json, tidy.jsonc or tidy.toml, on top of .editorconfig. Shared keys apply everywhere, and a language section overrides them:

{
  "width": 100,
  "js": { "semi": false, "quote": "single" },
  "markdown": { "wrap": "always" }
}

Node

import { format, check } from "tidyrs";

let output = format("<p   >hi</p>", { filepath: "index.html" });
//=> "<p>hi</p>\n"

check(output, { filepath: "index.html" });
//=> true

Rust

use tidy::{Language, Options, embed::Verbatim};

let language = Language::of_path("App.vue").unwrap();
let output = tidy::format(source, language, &Options::default(), Some("App.vue"), &mut Verbatim)?;

Benchmarks

Every tool checks every file of each corpus, using all cores, on an M1 Max. Times are the mean of both run orders. Embedded code is left alone here, so every tool does the same work.

Corpus	Files	tidy	bun fmt	oxfmt	dprint	Prettier
JavaScript	3,906	78 ms	100 ms	123 ms		8,528 ms
TypeScript	3,309	58 ms	85 ms	96 ms		7,523 ms
JSON	4,569	86 ms	149 ms	114 ms	323 ms	3,528 ms
CSS	300	7.2 ms	35 ms	47 ms	25 ms	654 ms
SCSS	101	4.6 ms	32 ms	46 ms	11 ms	340 ms
Less	396	9.7 ms	37 ms	48 ms	58 ms	1,491 ms
HTML	151	6.4 ms	34 ms	237 ms	14 ms	327 ms
Vue	230	7.3 ms	34 ms	435 ms	205 ms	684 ms
Handlebars	57	3.7 ms	30 ms	201 ms		279 ms
Markdown	2,834	37 ms	71 ms	80 ms	188 ms	6,618 ms
YAML	435	24 ms	35 ms	46 ms	104 ms	1,271 ms
TOML	375	8.6 ms	36 ms	49 ms	22 ms
GraphQL	2,511	37 ms	63 ms	72 ms	271 ms	1,988 ms
XML	6,784	130 ms			616 ms	6,017 ms
Dockerfiles	25	3.6 ms			3.7 ms	458 ms
INI	75	3.7 ms				147 ms
All but XML	12,071	280 ms	569 ms	1,232 ms	3,474 ms	18,548 ms

With embedded code formatted too, the gap grows: on all but XML, tidy takes 286 ms, bun fmt 609 ms, oxfmt 2.4 s, and Prettier 30.9 s.

The full tables, with one-thread times, Biome, taplo, yamlfmt, lightningcss and oxc's CSS formatter, are in bench/results/format. The scripts are bench/run.ts and bench/js.ts.

Differences from Prettier

tidy prints something else on purpose in a few places: where Prettier's output changes what your code means, where it would change again on the next run, and a few choices, like formatting JSDoc comments by default, as prettier-plugin-jsdoc does. Turn that off with "js": { "jsdoc": false }. Each case is listed, with an example, in deviations.md.

Credits

tidy ports a lot of great work: Prettier, Biome, oxc, Bun's Rust ports, taplo, dprint, and more. See notice.md for all of them.

lukeed/tidyPublic

readme.md