eslint-plugin-vitest

ESLint plugin for Vitest

Installation

You'll first need to install ESLint:

npm i eslint --save-dev

Next, install @vitest/eslint-plugin

npm install @vitest/eslint-plugin --save-dev

Usage

Make sure you're running ESLint v9.0.0 or higher for the latest version of this plugin to work. The following example is how your eslint.config.js should be setup for this plugin to work for you.

import vitest from "@vitest/eslint-plugin";

export default [
  {
    files: ["tests/**"], // or any other pattern
    plugins: {
      vitest
    },
    rules: {
      ...vitest.configs.recommended.rules, // you can also use vitest.configs.all.rules to enable all rules
      "vitest/max-nested-describe": ["error", { "max": 3 }] // you can also modify rules' behavior using option like this
    },
  },
];

If you're not using the latest version of ESLint (version v8.57.0 or lower) you can setup this plugin using the following configuration

Add vitest to the plugins section of your .eslintrc configuration file. You can omit the eslint-plugin- prefix:

{
  "plugins": ["@vitest"]
}

Then configure the rules you want to use under the rules section.

{
  "rules": {
    "vitest/max-nested-describe": [
      "error",
      {
        "max": 3
      }
    ]
  }
}

If you're using old ESLint configuration, make sure to use legacy key like the following

{
  "extends": ["plugin:@vitest/legacy-recommended"] // or legacy-all
}

Enabling with type-testing

Vitest ships with an optional type-testing feature, which is disabled by default.

If you're using this feature, you should also enabled typecheck in the settings for this plugin. This ensures that rules like expect-expect account for type-related assertions in tests.

import vitest from "@vitest/eslint-plugin";

export default [
  {
    files: ["tests/**"], // or any other pattern
    plugins: {
      vitest,
    },
    rules: {
      ...vitest.configs.recommended.rules,
    },
   settings: {
      vitest: {
        typecheck: true
      }
    },
    languageOptions: {
      globals: {
        ...vitest.environments.env.globals,
      },
    },
  },
]

Shareable configurations

Recommended

This plugin exports a recommended configuration that enforces good testing practices.

To enable this configuration with eslint.config.js, use vitest.configs.recommended:

import vitest from "@vitest/eslint-plugin";

export default [
  {
    files: ["tests/**"], // or any other pattern
     ...vitest.configs.recommended,
  }
]

All

If you want to enable all rules instead of only some you can do so by adding the all configuration to your eslint.config.js config file:

import vitest from "@vitest/eslint-plugin";

export default [
  {
    files: ["tests/**"], // or any other pattern
     ...vitest.configs.all,
  }
]

Rules

💼 Configurations enabled in.
⚠️ Configurations set to warn in.
🌐 Set in the all configuration.
✅ Set in the recommended configuration.
🔧 Automatically fixable by the --fix CLI option.
💡 Manually fixable by editor suggestions.
❌ Deprecated.

| Name                                                | Description | 💼 | ⚠️ | 🔧 | 💡 | ❌ | | :----------------------------------------------------------------------------------------------------------------------- | :-------------------------------------------------------------------- | :- | :- | :- | :- | :- | | consistent-test-filename | require .spec test file pattern | | 🌐 | | | | | consistent-test-it | enforce using test or it but not both | | 🌐 | 🔧 | | | | expect-expect | enforce having expectation in test body | ✅ | 🌐 | | | | | max-expects | enforce a maximum number of expect per test | | 🌐 | | | | | max-nested-describe | require describe block to be less than set max value or default value | | 🌐 | | | | | no-alias-methods | disallow alias methods | | 🌐 | 🔧 | | | | no-commented-out-tests | disallow commented out tests | ✅ | 🌐 | | | | | no-conditional-expect | disallow conditional expects | | 🌐 | | | | | no-conditional-in-test | disallow conditional tests | | 🌐 | | | | | no-conditional-tests | disallow conditional tests | | 🌐 | | | | | no-disabled-tests | disallow disabled tests | | 🌐 | | | | | no-done-callback | disallow using a callback in asynchronous tests and hooks | | 🌐 | | 💡 | ❌ | | no-duplicate-hooks | disallow duplicate hooks and teardown hooks | | 🌐 | | | | | no-focused-tests | disallow focused tests | | 🌐 | 🔧 | | | | no-hooks | disallow setup and teardown hooks | | 🌐 | | | | | no-identical-title | disallow identical titles | ✅ | 🌐 | 🔧 | | | | no-import-node-test | disallow importing node:test | ✅ | 🌐 | 🔧 | | | | no-interpolation-in-snapshots | disallow string interpolation in snapshots | | 🌐 | 🔧 | | | | no-large-snapshots | disallow large snapshots | | 🌐 | | | | | no-mocks-import | disallow importing from mocks directory | | 🌐 | | | | | no-restricted-matchers | disallow the use of certain matchers | | 🌐 | | | | | no-restricted-vi-methods | disallow specific vi. methods | | 🌐 | | | | | no-standalone-expect | disallow using expect outside of it or test blocks | | 🌐 | | | | | no-test-prefixes | disallow using test as a prefix | | 🌐 | 🔧 | | | | no-test-return-statement | disallow return statements in tests | | 🌐 | | | | | prefer-called-with | enforce using toBeCalledWith() or toHaveBeenCalledWith() | | 🌐 | 🔧 | | | | prefer-comparison-matcher | enforce using the built-in comparison matchers | | 🌐 | 🔧 | | | | prefer-each | enforce using each rather than manual loops | | 🌐 | | | | | prefer-equality-matcher | enforce using the built-in quality matchers | | 🌐 | | 💡 | | | prefer-expect-assertions | enforce using expect assertions instead of callbacks | | 🌐 | | 💡 | | | prefer-expect-resolves | enforce using expect().resolves over expect(await ...) syntax | | 🌐 | 🔧 | | | | prefer-hooks-in-order | enforce having hooks in consistent order | | 🌐 | | | | | prefer-hooks-on-top | enforce having hooks before any test cases | | 🌐 | | | | | prefer-lowercase-title | enforce lowercase titles | | 🌐 | 🔧 | | | | prefer-mock-promise-shorthand | enforce mock resolved/rejected shorthands for promises | | 🌐 | 🔧 | | | | prefer-snapshot-hint | enforce including a hint with external snapshots | | 🌐 | | | | | prefer-spy-on | enforce using vi.spyOn | | 🌐 | 🔧 | | | | prefer-strict-equal | enforce strict equal over equal | | 🌐 | | 💡 | | | prefer-to-be | enforce using toBe() | | 🌐 | 🔧 | | | | prefer-to-be-falsy | enforce using toBeFalsy() | | 🌐 | 🔧 | | | | prefer-to-be-object | enforce using toBeObject() | | 🌐 | 🔧 | | | | prefer-to-be-truthy | enforce using toBeTruthy | | 🌐 | 🔧 | | | | prefer-to-contain | enforce using toContain() | | 🌐 | 🔧 | | | | prefer-to-have-length | enforce using toHaveLength() | | 🌐 | 🔧 | | | | prefer-todo | enforce using test.todo | | 🌐 | 🔧 | | | | prefer-vi-mocked | Prefer vi.mocked() over fn as Mock | | 🌐 | 🔧 | | | | require-hook | require setup and teardown to be within a hook | | 🌐 | | | | | require-local-test-context-for-concurrent-snapshots | require local Test Context for concurrent snapshot tests | ✅ | 🌐 | | | | | require-to-throw-message | require toThrow() to be called with an error message | | 🌐 | | | | | require-top-level-describe | enforce that all tests are in a top-level describe | | 🌐 | | | | | valid-describe-callback | enforce valid describe callback | ✅ | 🌐 | | | | | valid-expect | enforce valid expect() usage | ✅ | 🌐 | 🔧 | | | | valid-title | enforce valid titles | ✅ | 🌐 | 🔧 | | | | valid-expect-in-promise | require promises that have expectations in their chain to be valid | | 🌐 | | | |

Credits

• eslint-plugin-jest Most of the rules in this plugin are essentially ports of Jest plugin rules with minor modifications

Licence

MIT Licence © 2022 - present veritem and contributors