biome-plugin-angular

Biome 2.x plugin that ports @angular-eslint rules to GritQL and adds modern Angular signal-based rules. For Angular 17-21 projects migrating from ESLint to Biome.

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Features

• 20 GritQL rules for Biome 2.x plugin system
• Ports the most-used @angular-eslint rules
• 6 new rules for modern Angular (signals, inject, host properties)
• CLI helper: biome-angular init|merge|remove|rules
• recommended and strict presets
• Zero runtime dependencies

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Requirements

Tool	Version
Node.js	>= 18
@biomejs/biome	>= 2.4.8
Angular	>= 17

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Installation

npm install --save-dev biome-plugin-angular @biomejs/biome

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Getting Started

Option A — CLI (recommended)

# Create a biome.json from scratch
npx biome-angular init

# Or add the plugin to your existing biome.json
npx biome-angular merge

Option B — Manual configuration

Add the plugin to your biome.json:

{
  "$schema": "https://biomejs.dev/schemas/2.4.8/schema.json",
  "plugins": ["biome-plugin-angular"]
}

Biome will load biome-manifest.jsonc from the plugin package automatically.

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Rules

High Priority

Rule	ESLint equivalent	Severity	Notes
prefer-standalone	@angular-eslint/prefer-standalone	error
no-empty-lifecycle-method	@angular-eslint/no-empty-lifecycle-method	warn

Conventions

Rule	ESLint equivalent	Severity	Notes
no-component-suffix	(new — Angular v20+)	warn	heuristic*
no-directive-suffix	(new — Angular v20+)	warn	heuristic*
no-service-suffix	(new — Angular v20+)	warn	heuristic*
component-selector	@angular-eslint/component-selector	warn
no-input-rename	@angular-eslint/no-input-rename	error
no-output-rename	@angular-eslint/no-output-rename	error
no-output-on-prefix	@angular-eslint/no-output-on-prefix	error
pipe-prefix	@angular-eslint/pipe-prefix	warn
sort-ngmodule-metadata-arrays	@angular-eslint/sort-ngmodule-metadata-arrays	warn	limited**

Quality

Rule	ESLint equivalent	Severity	Notes
use-lifecycle-interface	@angular-eslint/use-lifecycle-interface	warn
use-pipe-transform-interface	@angular-eslint/use-pipe-transform-interface	warn	non-functional***
contextual-lifecycle	@angular-eslint/contextual-lifecycle	error	non-functional***

Modern (Angular 17+)

Rule	ESLint equivalent	Severity	Notes
prefer-signal-inputs	(new)	warn	Angular 17.1+
prefer-output-function	(new)	warn	Angular 17.3+
prefer-signal-queries	(new)	warn	Angular 17.2+
prefer-model-signal	(new)	warn	Angular 17.2+
prefer-host-property	(new)	warn
prefer-inject-function	(new)	warn	heuristic*

GritQL Limitations

Biome's GritQL engine (2.4.8) cannot match @Decorator + class as a single pattern unit. This affects some rules:

• * heuristic: Rules match by class name or constructor shape without verifying the Angular decorator. Accurate in Angular projects; may false-positive in non-Angular code.
• ** limited: sort-ngmodule-metadata-arrays detects the presence of metadata arrays but cannot verify sort order.
• *** non-functional: Rules compile but cannot detect violations at runtime. Kept for forward-compatibility.

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CLI Reference

biome-angular init [--strict] [--force]
  Create a new biome.json preconfigured with this plugin.
  --strict   Use the strict preset (all rules as errors)
  --force    Overwrite existing biome.json

biome-angular merge [--strict]
  Add this plugin to your existing biome.json without overwriting.

biome-angular remove
  Remove all biome-plugin-angular rules and plugin reference from biome.json.

biome-angular rules
  Print all available rules and their implementation status.

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Presets

Two presets are available:

Preset	Description
recommended	All high-priority rules; no-empty-lifecycle-method as warn
strict	All high-priority rules as errors

Reference them in biome.json:

{ "extends": ["biome-plugin-angular/presets/strict"] }

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Migration from @angular-eslint

If you are migrating from ESLint + @angular-eslint, you can remove the following packages once the corresponding rules are available in this plugin:

npm uninstall eslint @angular-eslint/eslint-plugin @angular-eslint/template-parser

See rules-to-migrate.json for the full migration tracking list.

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Contributing

See CONTRIBUTING.md.

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License

MIT