Test Projects

Sample Project

GitHub - Play Online

WARNING

This feature is also known as a workspace. The workspace is deprecated since 3.2 and replaced with the projects configuration. They are functionally the same.

Vitest provides a way to define multiple project configurations within a single Vitest process. This feature is particularly useful for monorepo setups but can also be used to run tests with different configurations, such as resolve.alias, plugins, or test.browser and more.

Defining Projects

You can define projects in your root config:

vitest.config.ts

import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    projects: ['packages/*'],
  },
})

Project configurations are inlined configs, files, or glob patterns referencing your projects. For example, if you have a folder named packages that contains your projects, you can define an array in your root Vitest config:

vitest.config.ts

import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    projects: ['packages/*'],
  },
})

Vitest will treat every folder in packages as a separate project even if it doesn't have a config file inside. If this glob pattern matches any file, it will be considered a Vitest config even if it doesn't have a vitest in its name or has an obscure file extension.

WARNING

Vitest does not treat the root vitest.config file as a project unless it is explicitly specified in the configuration. Consequently, the root configuration will only influence global options such as reporters and coverage. Note that Vitest will always run certain plugin hooks, like apply, config, configResolved or configureServer, specified in the root config file. Vitest also uses the same plugins to execute global setups and custom coverage provider.

You can also reference projects with their config files:

vitest.config.ts

import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    projects: ['packages/*/vitest.config.{e2e,unit}.ts'],
  },
})

This pattern will only include projects with a vitest.config file that contains e2e or unit before the extension.

You can also define projects using inline configuration. The configuration supports both syntaxes simultaneously.

vitest.config.ts

import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    projects: [
      // matches every folder and file inside the `packages` folder
      'packages/*',
      {
        // add "extends: true" to inherit the options from the root config
        extends: true,
        test: {
          include: ['tests/**/*.{browser}.test.{ts,js}'],
          // it is recommended to define a name when using inline configs
          name: 'happy-dom',
          environment: 'happy-dom',
        }
      },
      {
        test: {
          include: ['tests/**/*.{node}.test.{ts,js}'],
          // color of the name label can be changed
          name: { label: 'node', color: 'green' },
          environment: 'node',
        }
      }
    ]
  }
})

WARNING

All projects must have unique names; otherwise, Vitest will throw an error. If a name is not provided in the inline configuration, Vitest will assign a number. For project configurations defined with glob syntax, Vitest will default to using the "name" property in the nearest package.json file or, if none exists, the folder name.

Projects do not support all configuration properties. For better type safety, use the defineProject method instead of defineConfig within project configuration files:

packages/a/vitest.config.ts

import {  } from 'vitest/config'

export default ({
  : {
    : 'jsdom',
    // "reporters" is not supported in a project config,
    // so it will show an error
    reporters: ['json']
No overload matches this call.
  The last overload gave the following error.
    Object literal may only specify known properties, and 'reporters' does not exist in type 'ProjectConfig'.
  }
})

Running tests

To run tests, define a script in your root package.json:

package.json

{
  "scripts": {
    "test": "vitest"
  }
}

Now tests can be run using your package manager:

npm

npm run test

yarn

yarn test

pnpm

pnpm run test

bun

bun run test

If you need to run tests only inside a single project, use the --project CLI option:

npm

npm run test --project e2e

yarn

yarn test --project e2e

pnpm

pnpm run test --project e2e

bun

bun run test --project e2e

TIP

CLI option --project can be used multiple times to filter out several projects:

npm

npm run test --project e2e --project unit

yarn

yarn test --project e2e --project unit

pnpm

pnpm run test --project e2e --project unit

bun

bun run test --project e2e --project unit

Configuration

None of the configuration options are inherited from the root-level config file. You can create a shared config file and merge it with the project config yourself:

packages/a/vitest.config.ts

import { defineProject, mergeConfig } from 'vitest/config'
import configShared from '../vitest.shared.js'

export default mergeConfig(
  configShared,
  defineProject({
    test: {
      environment: 'jsdom',
    }
  })
)

Additionally, you can use the extends option to inherit from your root-level configuration. All options will be merged.

vitest.config.ts

import { defineConfig } from 'vitest/config'
import react from '@vitejs/plugin-react'

export default defineConfig({
  plugins: [react()],
  test: {
    pool: 'threads',
    projects: [
      {
        // will inherit options from this config like plugins and pool
        extends: true,
        test: {
          name: 'unit',
          include: ['**/*.unit.test.ts'],
        },
      },
      {
        // won't inherit any options from this config
        // this is the default behaviour
        extends: false,
        test: {
          name: 'integration',
          include: ['**/*.integration.test.ts'],
        },
      },
    ],
  },
})

Unsupported Options

Some of the configuration options are not allowed in a project config. Most notably:

• coverage: coverage is done for the whole process
• reporters: only root-level reporters can be supported
• resolveSnapshotPath: only root-level resolver is respected
• all other options that don't affect test runners

All configuration options that are not supported inside a project configuration are marked with a * sign in the "Config" guide. They have to be defined once in the root config file.