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Coverage

Vitest supports Native code coverage via c8 and instrumented code coverage via istanbul.

Coverage Providers

TIP

Since Vitest v0.22.0

Both c8 and istanbul support are optional. By default, c8 will be used.

You can select the coverage tool by setting test.coverage.provider to either c8 or istanbul:

// vite.config.ts
import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    coverage: {
      provider: 'istanbul' // or 'c8'
    },
  },
})

// vite.config.ts
import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    coverage: {
      provider: 'istanbul' // or 'c8'
    },
  },
})

When you start the Vitest process, it will prompt you to install the corresponding support package automatically.

Or if you prefer to install them manually:

bash

# For c8
npm i -D @vitest/coverage-c8

# For istanbul
npm i -D @vitest/coverage-istanbul

# For c8
npm i -D @vitest/coverage-c8

# For istanbul
npm i -D @vitest/coverage-istanbul

Coverage Setup

To test with coverage enabled, you can pass the --coverage flag in CLI.

json

{
  "scripts": {
    "test": "vitest",
    "coverage": "vitest run --coverage"
  }
}

{
  "scripts": {
    "test": "vitest",
    "coverage": "vitest run --coverage"
  }
}

To configure it, set test.coverage options in your config file:

// vite.config.ts
import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    coverage: {
      reporter: ['text', 'json', 'html'],
    },
  },
})

// vite.config.ts
import { defineConfig } from 'vitest/config'

export default defineConfig({
  test: {
    coverage: {
      reporter: ['text', 'json', 'html'],
    },
  },
})

Custom Coverage Provider

It's also possible to provide your custom coverage provider by passing an object to the test.coverage.provider:

// vite.config.ts
import { defineConfig } from 'vitest/config'
import CustomCoverageProvider from 'my-custom-coverage-provider'

export default defineConfig({
  test: {
    coverage: {
      provider: CustomCoverageProvider()
    },
  },
})

// vite.config.ts
import { defineConfig } from 'vitest/config'
import CustomCoverageProvider from 'my-custom-coverage-provider'

export default defineConfig({
  test: {
    coverage: {
      provider: CustomCoverageProvider()
    },
  },
})

Please refer to the type definition for more details.

© 2021-Present Anthony Fu
© 2021-Present Matias Capeletto
Licensed under the MIT License.
https://vitest.dev/guide/coverage.html