prettier-compare

Original：🇺🇸 English

Translated

Compares code formatting and formatting IR between Biome and Prettier to ensure that Biome's formatting is consistent and correct.

2installs

Added on2026-02-18

NPX Install

npx skill4agent add biomejs/biome prettier-compare

Use

packages/prettier-compare/

to inspect any differences between Biome and Prettier formatting (including IR output) before shipping formatter changes.

Run every command from the repository root so relative paths resolve correctly.
Use
```
bun
```
(the CLI is a Bun script) and ensure dependencies have been installed.
Always pass
```
--rebuild
```
so the Biome WASM bundle matches your current Rust changes.

Snippets passed as CLI args:

bun packages/prettier-compare/bin/prettier-compare.js --rebuild 'const x={a:1,b:2}'

Force a language (useful when the tool cannot infer it from a filename):

bun packages/prettier-compare/bin/prettier-compare.js --rebuild -l ts 'const x: number = 1'

Compare files on disk:

bun packages/prettier-compare/bin/prettier-compare.js --rebuild -f src/example.tsx

Read from stdin (great for piping editor selections):

echo 'const x = 1' | bun packages/prettier-compare/bin/prettier-compare.js --rebuild -l js

Use
```
-l/--language
```
when formatting code without an extension so both formatters pick the correct parser.
Use
```
-f/--file
```
for large samples or snapshot tests so you can iterate directly on project fixtures.
Reference
```
packages/prettier-compare/README.md
```
for deeper CLI details; mirror any updates here, keeping the hard requirement that commands include
```
--rebuild
```
.
Use single quotes for code snippets passed as CLI arguments to avoid shell interpretation issues.
"\n" does not get escaped into a newline when passed as a CLI argument. You should write a literal newline or use a file instead.