eslint-plugin-vitest

0.5.4 verified Sat Apr 25 auth: no javascript

ESLint plugin for Vitest, providing test-specific linting rules. The latest stable version is 1.6.16, released on npm with type definitions included. This plugin helps enforce best practices in Vitest test suites, including rules for consistent naming, focused tests, and proper assertions. It supports both ESLint v8 (flat config and legacy) and v9. Key differentiators include type-testing support, a comprehensive set of rules (e.g., no-focused-tests, valid-expect), and compatibility with Vitest's chaining API. The plugin is actively maintained, with frequent releases addressing bugs and adding features. It requires ESLint >=8.57.0 and Vitest as peer dependencies.

Common errors

error Error: Failed to load plugin 'vitest' declared in '.eslintrc.json' ↓

cause Plugin not installed or ESLint cannot find it

fix

Run 'npm install --save-dev eslint-plugin-vitest' and ensure node_modules includes it.

error Definition for rule 'vitest/no-focused-tests' was not found ↓

cause Using a rule that doesn't exist or incorrect plugin version

fix

Check rule name spelling; verify plugin version supports the rule (v1.0+ includes core rules).

error TypeError: vitest.configs is not iterable ↓

cause Incorrect import or usage in flat config; configs is an object, not array

fix

Use: export default [ ...vitest.configs.recommended ] or spread properly.

error ESLint couldn't determine the plugin for rule 'vitest/expect-expect' ↓

cause Plugin not specified in 'plugins' array or object

fix

Add 'vitest' in the flat config's plugins object: { plugins: { vitest } }

Warnings

breaking ESLint v9 flat config requires different plugin structure than legacy .eslintrc ↓

fix Use import vitest from 'eslint-plugin-vitest' and spread vitest.configs.recommended in flat config.

deprecated The 'vitest/no-alias-methods' rule may have reversed alias direction in v1.6.12 ↓

fix Check your usage: toThrow/toThrowError alias direction was fixed. Update code if needed.

gotcha TypeScript type definitions are shipped but need '@typescript-eslint' for full integration ↓

fix Install and configure @typescript-eslint/parser and plugin to resolve type-aware rules.

breaking Plugin requires ESLint >=8.57.0; older versions may not work ↓

fix Upgrade ESLint to v8.57.0+ or use v9+ for flat config.

deprecated The 'all' config sets warn level; be aware if using spread ↓

fix Use 'recommended' instead of 'all' to avoid too many warnings.

Install

npm install eslint-plugin-vitest

yarn add eslint-plugin-vitest

pnpm add eslint-plugin-vitest

Imports

plugin (default)
wrong
```
const vitest = require('eslint-plugin-vitest')
```
correct
```
import vitest from 'eslint-plugin-vitest'
```
Default import provides the plugin object with configs and rules. CJS require works in Node, but ESM is recommended since v1.

vitest.configs.recommended

wrong

import { recommended } from 'eslint-plugin-vitest'

correct

import vitest from 'eslint-plugin-vitest'; export default [...vitest.configs.recommended]

Configs are accessed via the default import, not as named exports.

vitest.environments.env.globals
wrong
```
import { environments } from 'eslint-plugin-vitest'
```
correct
```
import vitest from 'eslint-plugin-vitest'; globals: { ...vitest.environments.env.globals }
```
Globals are under the '.environments.env.globals' property. Named import of 'environments' is not available.
Rule: vitest/no-focused-tests
wrong
```
rules: { no-focused-tests: 'error' }
```
correct
```
rules: { 'vitest/no-focused-tests': 'error' }
```
Rules must be prefixed with 'vitest/' in the config.

Quickstart

Flat config setup with recommended rules, preventing focused tests, and enabling typecheck support.

// Install: npm install --save-dev eslint eslint-plugin-vitest

// eslint.config.js (ESLint v9 flat config)
import vitest from 'eslint-plugin-vitest';

export default [
  {
    files: ['**/*.test.js', '**/*.test.ts'],
    plugins: {
      vitest,
    },
    rules: {
      ...vitest.configs.recommended.rules,
      'vitest/no-focused-tests': 'error',
    },
    settings: {
      vitest: {
        typecheck: true, // enable if using Vitest type-testing
      },
    },
  },
];