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Node API

WARNING

Vitest exposes experimental private API. Breaking changes might not follow SemVer, please pin Vitest's version when using it.

startVitest

You can start running Vitest tests using its Node API:

js
import { startVitest } from 'vitest/node'

const vitest = await startVitest('test')

await vitest?.close()

startVitest function returns Vitest instance if tests can be started. It returns undefined, if one of the following occurs:

  • Vitest didn't find the vite package (usually installed with Vitest)
  • If coverage is enabled and run mode is "test", but the coverage package is not installed (@vitest/coverage-v8 or @vitest/coverage-istanbul)
  • If the environment package is not installed (jsdom/happy-dom/@edge-runtime/vm)

If undefined is returned or tests failed during the run, Vitest sets process.exitCode to 1.

If watch mode is not enabled, Vitest will call close method.

If watch mode is enabled and the terminal supports TTY, Vitest will register console shortcuts.

You can pass down a list of filters as a second argument. Vitest will run only tests that contain at least one of the passed-down strings in their file path.

Additionally, you can use the third argument to pass in CLI arguments, which will override any test config options.

Alternatively, you can pass in the complete Vite config as the fourth argument, which will take precedence over any other user-defined options.

After running the tests, you can get the results from the state.getFiles API:

ts
const vitest = await startVitest('test')

console.log(vitest.state.getFiles()) // [{ type: 'file', ... }]

Since Vitest 2.1, it is recommended to use the "Reported Tasks" API together with the state.getFiles. In the future, Vitest will return those objects directly:

ts
const vitest = await startVitest('test')

const [fileTask] = vitest.state.getFiles()
const testFile = vitest.state.getReportedEntity(fileTask)

createVitest

You can create Vitest instance yourself using createVitest function. It returns the same Vitest instance as startVitest, but it doesn't start tests and doesn't validate installed packages.

js
import { createVitest } from 'vitest/node'

const vitest = await createVitest('test', {
  watch: false,
})

parseCLI

You can use this method to parse CLI arguments. It accepts a string (where arguments are split by a single space) or a strings array of CLI arguments in the same format that Vitest CLI uses. It returns a filter and options that you can later pass down to createVitest or startVitest methods.

ts
import { parseCLI } from 'vitest/node'

parseCLI('vitest ./files.ts --coverage --browser=chrome')

Vitest

Vitest instance requires the current test mode. It can be either:

  • test when running runtime tests
  • benchmark when running benchmarks

mode

test

Test mode will only call functions inside test or it, and throws an error when bench is encountered. This mode uses include and exclude options in the config to find test files.

benchmark

Benchmark mode calls bench functions and throws an error, when it encounters test or it. This mode uses benchmark.include and benchmark.exclude options in the config to find benchmark files.

start

You can start running tests or benchmarks with start method. You can pass an array of strings to filter test files.

provide

Vitest exposes provide method which is a shorthand for vitest.getCoreWorkspaceProject().provide. With this method you can pass down values from the main thread to tests. All values are checked with structuredClone before they are stored, but the values themselves are not cloned.

To recieve the values in the test, you need to import inject method from vitest entrypont:

ts
import { inject } from 'vitest'
const port = inject('wsPort') // 3000

For better type safety, we encourage you to augment the type of ProvidedContext:

ts
import { createVitest } from 'vitest/node'

const vitest = await createVitest('test', {
  watch: false,
})
vitest.provide('wsPort', 3000)

declare module 'vitest' {
  export interface ProvidedContext {
    wsPort: number
  }
}

WARNING

Technically, provide is a method of WorkspaceProject, so it is limited to the specific project. However, all projects inherit the values from the core project which makes vitest.provide universal way of passing down values to tests.

TIP

This method is also available to global setup files for cases where you don't want to use the public API:

js
export default function setup({ provide }) {
  provide('wsPort', 3000)
}

Released under the MIT License.