bun lint Config

@pleaseai/bun-lint-config provides the rules of @pleaseai/eslint-config that bun lint runs natively, as the [lint] tables of a bunfig.toml. The package ships one file, lint.toml, generated from the ESLint config.

bun lint is only in Bun canary builds for now. bunfig.toml has no extends, so the tables are copied into your project’s bunfig.toml.

What it covers

The generator keeps:

• the rules Bun has built in: ESLint core, @typescript-eslint, unicorn, import, and node (eslint-plugin-n), with their options
• the file scoping of the ESLint config, as [[lint.overrides]] for TypeScript files, tests, scripts, .d.ts, config files, and so on
• the global ignores, as ignorePatterns
• rules that have a native equivalent under another name, mapped onto it (see below)

What is left out:

• plugins Bun does not run natively, apart from the rules mapped below: stylistic (style/*), regexp, jsdoc, antfu, perfectionist, unused-imports, eslint-comments, command, and e18e
• JSON, YAML, TOML, and Markdown, which bun lint does not lint
• formatting: the package configures [lint] only, not [fmt]

Bun’s own default rules stay on even where @pleaseai/eslint-config does not enable them: 14 ESLint core rules (such as no-constant-condition, for-direction, no-useless-escape, and no-unsafe-optional-chaining), the bun:test rules in files that import bun:test, and the React rules when react is a dependency. So bun lint can report a little more than ESLint.

Mapped rules

src/rule-map.ts maps a rule that bun lint has no native version of onto the native rule that does the same, and the generator writes it under the native name, with the same severity, options, and file scoping:

• antfu’s test/* (vitest) rules onto vitest/*: consistent-test-it, no-identical-title, no-import-node-test, prefer-hooks-in-order, prefer-lowercase-title, and no-only-tests as vitest/no-focused-tests
• unused-imports/no-unused-vars onto @typescript-eslint/no-unused-vars
• the style/jsx-* rules onto react/jsx-*: closing-bracket-location, closing-tag-location, curly-brace-presence, curly-newline, curly-spacing, equals-spacing, first-prop-new-line, indent-props, max-props-per-line, one-expression-per-line, and tag-spacing
• antfu/no-top-level-await onto n/no-top-level-await
• e18e/prefer-array-some, prefer-date-now, prefer-regex-test, and prefer-object-has-own onto unicorn/prefer-array-some, unicorn/prefer-date-now, unicorn/prefer-regexp-test, and prefer-object-has-own

A mapped rule owns its target: the ESLint config’s own entries for the target are dropped (it turns @typescript-eslint/no-unused-vars off in TypeScript files, for example), and the generator fails if one of them is not off. jsx-wrap-multilines is not mapped, because Bun rejects its propertyValue option.

The mapped rules are close to the ESLint ones, not identical:

• the vitest rules need an import from vitest; in a file that imports bun:test, Bun runs its own bun:test rules instead
• findings can start at a different column: no-import-node-test points at the module name, no-identical-title at the title, prefer-array-some at filter, and prefer-regexp-test at the regular expression
• Bun runs no-unused-vars and @typescript-eslint/no-unused-vars as one rule, so the mapped unused-imports/no-unused-vars owns no-unused-vars too and its options apply in every file; the core rule, which ESLint also runs in JavaScript files, is not written
• the react/jsx-* rules run without react as a dependency, because the config turns them on explicitly

Usage

Run the CLI and select bun-lint-config:

bunx @pleaseai/code-style init

init installs the package and writes lint.toml into bunfig.toml between # >>> @pleaseai/bun-lint-config and # <<< @pleaseai/bun-lint-config comments. Run init again after an upgrade to refresh the block; the rest of bunfig.toml is kept. If bunfig.toml already sets lint options outside the block, init leaves the file alone and asks you to remove them first.

To copy it by hand, append the file to bunfig.toml and keep the tables at the end of the file, since a key after them belongs to the last table:

bun add -D @pleaseai/bun-lint-config
cat node_modules/@pleaseai/bun-lint-config/lint.toml >> bunfig.toml

bun --config=node_modules/@pleaseai/bun-lint-config/lint.toml lint is not the same: --config replaces bunfig.toml instead of adding to it.

Running bun lint

• A lint script in package.json shadows bun lint. Run bun lint --no-script, or make the script bun lint.
• Do not use this next to an eslint.config.* file. Next to an ESLint config, bun lint reads that config and applies the [lint] keys on top of it, so pick one of the two.