VitestTest Context
Inspired by Playwright Fixtures, Vitest's test context allows you to define utils, states, and fixtures that can be used in your tests.
Usage
The first argument for each test callback is a test context.
ts
import { it } from 'vitest'
it('should work', (ctx) => {
// prints name of the test
console.log(ctx.meta.name)
})
import { it } from 'vitest'
it('should work', (ctx) => {
// prints name of the test
console.log(ctx.meta.name)
})
Built-in Test Context
context.meta
A readonly object containing metadata about the test.
context.expect
The expect API bound to the current test.
Extend Test Context
The contexts are different for each test. You can access and extend them within the beforeEach and afterEach hooks.
ts
import { beforeEach, it } from 'vitest'
beforeEach(async (context) => {
// extend context
context.foo = 'bar'
})
it('should work', ({ foo }) => {
console.log(foo) // 'bar'
})
import { beforeEach, it } from 'vitest'
beforeEach(async (context) => {
// extend context
context.foo = 'bar'
})
it('should work', ({ foo }) => {
console.log(foo) // 'bar'
})
TypeScript
To provide property types for all your custom contexts, you can aggregate the TestContext type by adding
ts
declare module 'vitest' {
export interface TestContext {
foo?: string
}
}
declare module 'vitest' {
export interface TestContext {
foo?: string
}
}
If you want to provide property types only for specific beforeEach, afterEach, it and test hooks, you can pass the type as a generic.
ts
interface LocalTestContext {
foo: string
}
beforeEach<LocalTestContext>(async (context) => {
// typeof context is 'TestContext & LocalTestContext'
context.foo = 'bar'
})
it<LocalTestContext>('should work', ({ foo }) => {
// typeof foo is 'string'
console.log(foo) // 'bar'
})
interface LocalTestContext {
foo: string
}
beforeEach<LocalTestContext>(async (context) => {
// typeof context is 'TestContext & LocalTestContext'
context.foo = 'bar'
})
it<LocalTestContext>('should work', ({ foo }) => {
// typeof foo is 'string'
console.log(foo) // 'bar'
})