Test API Reference
The following types are used in the type signatures below
type Awaitable<T> = T | PromiseLike<T>
type TestFunction = () => Awaitable<void>
interface TestOptions {
/**
* Will fail the test if it takes too long to execute
*/
timeout?: number
/**
* Will retry the test specific number of times if it fails
*
* @default 0
*/
retry?: number
/**
* Will repeat the same test several times even if it fails each time
* If you have "retry" option and it fails, it will use every retry in each cycle
* Useful for debugging random failings
*
* @default 0
*/
repeats?: number
}
When a test function returns a promise, the runner will wait until it is resolved to collect async expectations. If the promise is rejected, the test will fail.
TIP
In Jest, TestFunction
can also be of type (done: DoneCallback) => void
. If this form is used, the test will not be concluded until done
is called. You can achieve the same using an async
function, see the Migration guide Done Callback section.
Most options support both dot-syntax and object-syntax allowing you to use whatever style you prefer.
import { test } from 'vitest'
test.skip('skipped test', () => {
// some logic that fails right now
})
import { test } from 'vitest'
test('skipped test', { skip: true }, () => {
// some logic that fails right now
})
test
- Alias:
it
test
defines a set of related expectations. It receives the test name and a function that holds the expectations to test.
Optionally, you can provide a timeout (in milliseconds) for specifying how long to wait before terminating. The default is 5 seconds, and can be configured globally with testTimeout
import { expect, test } from 'vitest'
test('should work as expected', () => {
expect(Math.sqrt(4)).toBe(2)
})
test.extend
- Alias:
it.extend
Use test.extend
to extend the test context with custom fixtures. This will return a new test
and it's also extendable, so you can compose more fixtures or override existing ones by extending it as you need. See Extend Test Context for more information.
import { expect, test } from 'vitest'
const todos = []
const archive = []
const myTest = test.extend({
todos: async ({ task }, use) => {
todos.push(1, 2, 3)
await use(todos)
todos.length = 0
},
archive
})
myTest('add item', ({ todos }) => {
expect(todos.length).toBe(3)
todos.push(4)
expect(todos.length).toBe(4)
})
test.skip
- Alias:
it.skip
If you want to skip running certain tests, but you don't want to delete the code due to any reason, you can use test.skip
to avoid running them.
import { assert, test } from 'vitest'
test.skip('skipped test', () => {
// Test skipped, no error
assert.equal(Math.sqrt(4), 3)
})
You can also skip test by calling skip
on its context dynamically:
import { assert, test } from 'vitest'
test('skipped test', (context) => {
context.skip()
// Test skipped, no error
assert.equal(Math.sqrt(4), 3)
})
test.skipIf
- Alias:
it.skipIf
In some cases you might run tests multiple times with different environments, and some of the tests might be environment-specific. Instead of wrapping the test code with if
, you can use test.skipIf
to skip the test whenever the condition is truthy.
import { assert, test } from 'vitest'
const isDev = process.env.NODE_ENV === 'development'
test.skipIf(isDev)('prod only test', () => {
// this test only runs in production
})
WARNING
You cannot use this syntax when using Vitest as type checker.
test.runIf
- Alias:
it.runIf
Opposite of test.skipIf.
import { assert, test } from 'vitest'
const isDev = process.env.NODE_ENV === 'development'
test.runIf(isDev)('dev only test', () => {
// this test only runs in development
})
WARNING
You cannot use this syntax when using Vitest as type checker.
test.only
- Alias:
it.only
Use test.only
to only run certain tests in a given suite. This is useful when debugging.
Optionally, you can provide a timeout (in milliseconds) for specifying how long to wait before terminating. The default is 5 seconds, and can be configured globally with testTimeout.
import { assert, test } from 'vitest'
test.only('test', () => {
// Only this test (and others marked with only) are run
assert.equal(Math.sqrt(4), 2)
})
Sometimes it is very useful to run only
tests in a certain file, ignoring all other tests from the whole test suite, which pollute the output.
In order to do that run vitest
with specific file containing the tests in question.
# vitest interesting.test.ts
test.concurrent
- Alias:
it.concurrent
test.concurrent
marks consecutive tests to be run in parallel. It receives the test name, an async function with the tests to collect, and an optional timeout (in milliseconds).
import { describe, test } from 'vitest'
// The two tests marked with concurrent will be run in parallel
describe('suite', () => {
test('serial test', async () => { /* ... */ })
test.concurrent('concurrent test 1', async () => { /* ... */ })
test.concurrent('concurrent test 2', async () => { /* ... */ })
})
test.skip
, test.only
, and test.todo
works with concurrent tests. All the following combinations are valid:
test.concurrent(/* ... */)
test.skip.concurrent(/* ... */) // or test.concurrent.skip(/* ... */)
test.only.concurrent(/* ... */) // or test.concurrent.only(/* ... */)
test.todo.concurrent(/* ... */) // or test.concurrent.todo(/* ... */)
When running concurrent tests, Snapshots and Assertions must use expect
from the local Test Context to ensure the right test is detected.
test.concurrent('test 1', async ({ expect }) => {
expect(foo).toMatchSnapshot()
})
test.concurrent('test 2', async ({ expect }) => {
expect(foo).toMatchSnapshot()
})
WARNING
You cannot use this syntax when using Vitest as type checker.
test.sequential
- Alias:
it.sequential
test.sequential
marks a test as sequential. This is useful if you want to run tests in sequence within describe.concurrent
or with the --sequence.concurrent
command option.
import { describe, test } from 'vitest'
// with config option { sequence: { concurrent: true } }
test('concurrent test 1', async () => { /* ... */ })
test('concurrent test 2', async () => { /* ... */ })
test.sequential('sequential test 1', async () => { /* ... */ })
test.sequential('sequential test 2', async () => { /* ... */ })
// within concurrent suite
describe.concurrent('suite', () => {
test('concurrent test 1', async () => { /* ... */ })
test('concurrent test 2', async () => { /* ... */ })
test.sequential('sequential test 1', async () => { /* ... */ })
test.sequential('sequential test 2', async () => { /* ... */ })
})
test.todo
- Alias:
it.todo
Use test.todo
to stub tests to be implemented later. An entry will be shown in the report for the tests so you know how many tests you still need to implement.
// An entry will be shown in the report for this test
test.todo('unimplemented test')
test.fails
- Alias:
it.fails
Use test.fails
to indicate that an assertion will fail explicitly.
import { expect, test } from 'vitest'
function myAsyncFunc() {
return new Promise(resolve => resolve(1))
}
test.fails('fail test', async () => {
await expect(myAsyncFunc()).rejects.toBe(1)
})
WARNING
You cannot use this syntax when using Vitest as type checker.
test.each
- Alias:
it.each
TIP
While test.each
is provided for Jest compatibility, Vitest also has test.for
with an additional feature to integrate TestContext
.
Use test.each
when you need to run the same test with different variables. You can inject parameters with printf formatting in the test name in the order of the test function parameters.
%s
: string%d
: number%i
: integer%f
: floating point value%j
: json%o
: object%#
: index of the test case%%
: single percent sign ('%')
import { expect, test } from 'vitest'
test.each([
[1, 1, 2],
[1, 2, 3],
[2, 1, 3],
])('add(%i, %i) -> %i', (a, b, expected) => {
expect(a + b).toBe(expected)
})
// this will return
// ✓ add(1, 1) -> 2
// ✓ add(1, 2) -> 3
// ✓ add(2, 1) -> 3
You can also access object properties with $
prefix, if you are using objects as arguments:
test.each([
{ a: 1, b: 1, expected: 2 },
{ a: 1, b: 2, expected: 3 },
{ a: 2, b: 1, expected: 3 },
])('add($a, $b) -> $expected', ({ a, b, expected }) => {
expect(a + b).toBe(expected)
})
// this will return
// ✓ add(1, 1) -> 2
// ✓ add(1, 2) -> 3
// ✓ add(2, 1) -> 3
You can also access Object attributes with .
, if you are using objects as arguments:
test.each`
a | b | expected
${{ val: 1 }} | ${'b'} | ${'1b'}
${{ val: 2 }} | ${'b'} | ${'2b'}
${{ val: 3 }} | ${'b'} | ${'3b'}
`('add($a.val, $b) -> $expected', ({ a, b, expected }) => {
expect(a.val + b).toBe(expected)
})
// this will return
// ✓ add(1, b) -> 1b
// ✓ add(2, b) -> 2b
// ✓ add(3, b) -> 3b
Starting from Vitest 0.25.3, you can also use template string table.
- First row should be column names, separated by
|
; - One or more subsequent rows of data supplied as template literal expressions using
${value}
syntax.
import { expect, test } from 'vitest'
test.each`
a | b | expected
${1} | ${1} | ${2}
${'a'} | ${'b'} | ${'ab'}
${[]} | ${'b'} | ${'b'}
${{}} | ${'b'} | ${'[object Object]b'}
${{ asd: 1 }} | ${'b'} | ${'[object Object]b'}
`('returns $expected when $a is added $b', ({ a, b, expected }) => {
expect(a + b).toBe(expected)
})
TIP
Vitest processes $values
with Chai format
method. If the value is too truncated, you can increase chaiConfig.truncateThreshold in your config file.
WARNING
You cannot use this syntax when using Vitest as type checker.
test.for
- Alias:
it.for
Alternative of test.each
to provide TestContext
.
The difference from test.each
is how array case is provided in the arguments. Other non array case (including template string usage) works exactly same.
// `each` spreads array case
test.each([
[1, 1, 2],
[1, 2, 3],
[2, 1, 3],
])('add(%i, %i) -> %i', (a, b, expected) => {
expect(a + b).toBe(expected)
})
// `for` doesn't spread array case
test.for([
[1, 1, 2],
[1, 2, 3],
[2, 1, 3],
])('add(%i, %i) -> %i', ([a, b, expected]) => {
expect(a + b).toBe(expected)
})
2nd argument is TestContext
and it can be used for concurrent snapshot, for example,
test.concurrent.for([
[1, 1],
[1, 2],
[2, 1],
])('add(%i, %i)', ([a, b], { expect }) => {
expect(a + b).matchSnapshot()
})
bench
- Type:
(name: string | Function, fn: BenchFunction, options?: BenchOptions) => void
bench
defines a benchmark. In Vitest terms benchmark is a function that defines a series of operations. Vitest runs this function multiple times to display different performance results.
Vitest uses tinybench
library under the hood, inheriting all its options that can be used as a third argument.
import { bench } from 'vitest'
bench('normal sorting', () => {
const x = [1, 5, 4, 2, 3]
x.sort((a, b) => {
return a - b
})
}, { time: 1000 })
export interface Options {
/**
* time needed for running a benchmark task (milliseconds)
* @default 500
*/
time?: number
/**
* number of times that a task should run if even the time option is finished
* @default 10
*/
iterations?: number
/**
* function to get the current timestamp in milliseconds
*/
now?: () => number
/**
* An AbortSignal for aborting the benchmark
*/
signal?: AbortSignal
/**
* Throw if a task fails (events will not work if true)
*/
throws?: boolean
/**
* warmup time (milliseconds)
* @default 100ms
*/
warmupTime?: number
/**
* warmup iterations
* @default 5
*/
warmupIterations?: number
/**
* setup function to run before each benchmark task (cycle)
*/
setup?: Hook
/**
* teardown function to run after each benchmark task (cycle)
*/
teardown?: Hook
}
After the test case is run, the output structure information is as follows:
name hz min max mean p75 p99 p995 p999 rme samples
· normal sorting 6,526,368.12 0.0001 0.3638 0.0002 0.0002 0.0002 0.0002 0.0004 ±1.41% 652638
export interface TaskResult {
/*
* the last error that was thrown while running the task
*/
error?: unknown
/**
* The amount of time in milliseconds to run the benchmark task (cycle).
*/
totalTime: number
/**
* the minimum value in the samples
*/
min: number
/**
* the maximum value in the samples
*/
max: number
/**
* the number of operations per second
*/
hz: number
/**
* how long each operation takes (ms)
*/
period: number
/**
* task samples of each task iteration time (ms)
*/
samples: number[]
/**
* samples mean/average (estimate of the population mean)
*/
mean: number
/**
* samples variance (estimate of the population variance)
*/
variance: number
/**
* samples standard deviation (estimate of the population standard deviation)
*/
sd: number
/**
* standard error of the mean (a.k.a. the standard deviation of the sampling distribution of the sample mean)
*/
sem: number
/**
* degrees of freedom
*/
df: number
/**
* critical value of the samples
*/
critical: number
/**
* margin of error
*/
moe: number
/**
* relative margin of error
*/
rme: number
/**
* median absolute deviation
*/
mad: number
/**
* p50/median percentile
*/
p50: number
/**
* p75 percentile
*/
p75: number
/**
* p99 percentile
*/
p99: number
/**
* p995 percentile
*/
p995: number
/**
* p999 percentile
*/
p999: number
}
bench.skip
- Type:
(name: string | Function, fn: BenchFunction, options?: BenchOptions) => void
You can use bench.skip
syntax to skip running certain benchmarks.
import { bench } from 'vitest'
bench.skip('normal sorting', () => {
const x = [1, 5, 4, 2, 3]
x.sort((a, b) => {
return a - b
})
})
bench.only
- Type:
(name: string | Function, fn: BenchFunction, options?: BenchOptions) => void
Use bench.only
to only run certain benchmarks in a given suite. This is useful when debugging.
import { bench } from 'vitest'
bench.only('normal sorting', () => {
const x = [1, 5, 4, 2, 3]
x.sort((a, b) => {
return a - b
})
})
bench.todo
- Type:
(name: string | Function) => void
Use bench.todo
to stub benchmarks to be implemented later.
import { bench } from 'vitest'
bench.todo('unimplemented test')
describe
When you use test
or bench
in the top level of file, they are collected as part of the implicit suite for it. Using describe
you can define a new suite in the current context, as a set of related tests or benchmarks and other nested suites. A suite lets you organize your tests and benchmarks so reports are more clear.
// basic.spec.ts
// organizing tests
import { describe, expect, test } from 'vitest'
const person = {
isActive: true,
age: 32,
}
describe('person', () => {
test('person is defined', () => {
expect(person).toBeDefined()
})
test('is active', () => {
expect(person.isActive).toBeTruthy()
})
test('age limit', () => {
expect(person.age).toBeLessThanOrEqual(32)
})
})
// basic.bench.ts
// organizing benchmarks
import { bench, describe } from 'vitest'
describe('sort', () => {
bench('normal', () => {
const x = [1, 5, 4, 2, 3]
x.sort((a, b) => {
return a - b
})
})
bench('reverse', () => {
const x = [1, 5, 4, 2, 3]
x.reverse().sort((a, b) => {
return a - b
})
})
})
You can also nest describe blocks if you have a hierarchy of tests or benchmarks:
import { describe, expect, test } from 'vitest'
function numberToCurrency(value: number | string) {
if (typeof value !== 'number') {
throw new TypeError('Value must be a number')
}
return value.toFixed(2).toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',')
}
describe('numberToCurrency', () => {
describe('given an invalid number', () => {
test('composed of non-numbers to throw error', () => {
expect(() => numberToCurrency('abc')).toThrowError()
})
})
describe('given a valid number', () => {
test('returns the correct currency format', () => {
expect(numberToCurrency(10000)).toBe('10,000.00')
})
})
})
describe.skip
- Alias:
suite.skip
Use describe.skip
in a suite to avoid running a particular describe block.
import { assert, describe, test } from 'vitest'
describe.skip('skipped suite', () => {
test('sqrt', () => {
// Suite skipped, no error
assert.equal(Math.sqrt(4), 3)
})
})
describe.skipIf
- Alias:
suite.skipIf
In some cases, you might run suites multiple times with different environments, and some of the suites might be environment-specific. Instead of wrapping the suite with if
, you can use describe.skipIf
to skip the suite whenever the condition is truthy.
import { describe, test } from 'vitest'
const isDev = process.env.NODE_ENV === 'development'
describe.skipIf(isDev)('prod only test suite', () => {
// this test suite only runs in production
})
WARNING
You cannot use this syntax when using Vitest as type checker.
describe.runIf
- Alias:
suite.runIf
Opposite of describe.skipIf.
import { assert, describe, test } from 'vitest'
const isDev = process.env.NODE_ENV === 'development'
describe.runIf(isDev)('dev only test suite', () => {
// this test suite only runs in development
})
WARNING
You cannot use this syntax when using Vitest as type checker.
describe.only
- Type:
(name: string | Function, fn: TestFunction, options?: number | TestOptions) => void
Use describe.only
to only run certain suites
import { assert, describe, test } from 'vitest'
// Only this suite (and others marked with only) are run
describe.only('suite', () => {
test('sqrt', () => {
assert.equal(Math.sqrt(4), 3)
})
})
describe('other suite', () => {
// ... will be skipped
})
Sometimes it is very useful to run only
tests in a certain file, ignoring all other tests from the whole test suite, which pollute the output.
In order to do that run vitest
with specific file containing the tests in question.
# vitest interesting.test.ts
describe.concurrent
- Alias:
suite.concurrent
describe.concurrent
runs all inner suites and tests in parallel
import { describe, test } from 'vitest'
// All suites and tests within this suite will be run in parallel
describe.concurrent('suite', () => {
test('concurrent test 1', async () => { /* ... */ })
describe('concurrent suite 2', async () => {
test('concurrent test inner 1', async () => { /* ... */ })
test('concurrent test inner 2', async () => { /* ... */ })
})
test.concurrent('concurrent test 3', async () => { /* ... */ })
})
.skip
, .only
, and .todo
works with concurrent suites. All the following combinations are valid:
describe.concurrent(/* ... */)
describe.skip.concurrent(/* ... */) // or describe.concurrent.skip(/* ... */)
describe.only.concurrent(/* ... */) // or describe.concurrent.only(/* ... */)
describe.todo.concurrent(/* ... */) // or describe.concurrent.todo(/* ... */)
When running concurrent tests, Snapshots and Assertions must use expect
from the local Test Context to ensure the right test is detected.
describe.concurrent('suite', () => {
test('concurrent test 1', async ({ expect }) => {
expect(foo).toMatchSnapshot()
})
test('concurrent test 2', async ({ expect }) => {
expect(foo).toMatchSnapshot()
})
})
WARNING
You cannot use this syntax when using Vitest as type checker.
describe.sequential
- Alias:
suite.sequential
describe.sequential
in a suite marks every test as sequential. This is useful if you want to run tests in sequence within describe.concurrent
or with the --sequence.concurrent
command option.
import { describe, test } from 'vitest'
describe.concurrent('suite', () => {
test('concurrent test 1', async () => { /* ... */ })
test('concurrent test 2', async () => { /* ... */ })
describe.sequential('', () => {
test('sequential test 1', async () => { /* ... */ })
test('sequential test 2', async () => { /* ... */ })
})
})
describe.shuffle
- Alias:
suite.shuffle
Vitest provides a way to run all tests in random order via CLI flag --sequence.shuffle
or config option sequence.shuffle
, but if you want to have only part of your test suite to run tests in random order, you can mark it with this flag.
import { describe, test } from 'vitest'
// or describe('suite', { shuffle: true }, ...)
describe.shuffle('suite', () => {
test('random test 1', async () => { /* ... */ })
test('random test 2', async () => { /* ... */ })
test('random test 3', async () => { /* ... */ })
// `shuffle` is inherited
describe('still random', () => {
test('random 4.1', async () => { /* ... */ })
test('random 4.2', async () => { /* ... */ })
})
// disable shuffle inside
describe('not random', { shuffle: false }, () => {
test('in order 5.1', async () => { /* ... */ })
test('in order 5.2', async () => { /* ... */ })
})
})
// order depends on sequence.seed option in config (Date.now() by default)
.skip
, .only
, and .todo
works with random suites.
WARNING
You cannot use this syntax when using Vitest as type checker.
describe.todo
- Alias:
suite.todo
Use describe.todo
to stub suites to be implemented later. An entry will be shown in the report for the tests so you know how many tests you still need to implement.
// An entry will be shown in the report for this suite
describe.todo('unimplemented suite')
describe.each
- Alias:
suite.each
Use describe.each
if you have more than one test that depends on the same data.
import { describe, expect, test } from 'vitest'
describe.each([
{ a: 1, b: 1, expected: 2 },
{ a: 1, b: 2, expected: 3 },
{ a: 2, b: 1, expected: 3 },
])('describe object add($a, $b)', ({ a, b, expected }) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected)
})
test(`returned value not be greater than ${expected}`, () => {
expect(a + b).not.toBeGreaterThan(expected)
})
test(`returned value not be less than ${expected}`, () => {
expect(a + b).not.toBeLessThan(expected)
})
})
Starting from Vitest 0.25.3, you can also use template string table.
- First row should be column names, separated by
|
; - One or more subsequent rows of data supplied as template literal expressions using
${value}
syntax.
import { describe, expect, test } from 'vitest'
describe.each`
a | b | expected
${1} | ${1} | ${2}
${'a'} | ${'b'} | ${'ab'}
${[]} | ${'b'} | ${'b'}
${{}} | ${'b'} | ${'[object Object]b'}
${{ asd: 1 }} | ${'b'} | ${'[object Object]b'}
`('describe template string add($a, $b)', ({ a, b, expected }) => {
test(`returns ${expected}`, () => {
expect(a + b).toBe(expected)
})
})
WARNING
You cannot use this syntax when using Vitest as type checker.
Setup and Teardown
These functions allow you to hook into the life cycle of tests to avoid repeating setup and teardown code. They apply to the current context: the file if they are used at the top-level or the current suite if they are inside a describe
block. These hooks are not called, when you are running Vitest as a type checker.
beforeEach
- Type:
beforeEach(fn: () => Awaitable<void>, timeout?: number)
Register a callback to be called before each of the tests in the current context runs. If the function returns a promise, Vitest waits until the promise resolve before running the test.
Optionally, you can pass a timeout (in milliseconds) defining how long to wait before terminating. The default is 5 seconds.
import { beforeEach } from 'vitest'
beforeEach(async () => {
// Clear mocks and add some testing data after before each test run
await stopMocking()
await addUser({ name: 'John' })
})
Here, the beforeEach
ensures that user is added for each test.
beforeEach
also accepts an optional cleanup function (equivalent to afterEach
).
import { beforeEach } from 'vitest'
beforeEach(async () => {
// called once before each test run
await prepareSomething()
// clean up function, called once after each test run
return async () => {
await resetSomething()
}
})
afterEach
- Type:
afterEach(fn: () => Awaitable<void>, timeout?: number)
Register a callback to be called after each one of the tests in the current context completes. If the function returns a promise, Vitest waits until the promise resolve before continuing.
Optionally, you can provide a timeout (in milliseconds) for specifying how long to wait before terminating. The default is 5 seconds.
import { afterEach } from 'vitest'
afterEach(async () => {
await clearTestingData() // clear testing data after each test run
})
Here, the afterEach
ensures that testing data is cleared after each test runs.
TIP
Vitest 1.3.0 added onTestFinished
hook. You can call it during the test execution to cleanup any state after the test has finished running.
beforeAll
- Type:
beforeAll(fn: () => Awaitable<void>, timeout?: number)
Register a callback to be called once before starting to run all tests in the current context. If the function returns a promise, Vitest waits until the promise resolve before running tests.
Optionally, you can provide a timeout (in milliseconds) for specifying how long to wait before terminating. The default is 5 seconds.
import { beforeAll } from 'vitest'
beforeAll(async () => {
await startMocking() // called once before all tests run
})
Here the beforeAll
ensures that the mock data is set up before tests run.
beforeAll
also accepts an optional cleanup function (equivalent to afterAll
).
import { beforeAll } from 'vitest'
beforeAll(async () => {
// called once before all tests run
await startMocking()
// clean up function, called once after all tests run
return async () => {
await stopMocking()
}
})
afterAll
- Type:
afterAll(fn: () => Awaitable<void>, timeout?: number)
Register a callback to be called once after all tests have run in the current context. If the function returns a promise, Vitest waits until the promise resolve before continuing.
Optionally, you can provide a timeout (in milliseconds) for specifying how long to wait before terminating. The default is 5 seconds.
import { afterAll } from 'vitest'
afterAll(async () => {
await stopMocking() // this method is called after all tests run
})
Here the afterAll
ensures that stopMocking
method is called after all tests run.
Test Hooks
Vitest provides a few hooks that you can call during the test execution to cleanup the state when the test has finished runnning.
WARNING
These hooks will throw an error if they are called outside of the test body.
onTestFinished
This hook is always called after the test has finished running. It is called after afterEach
hooks since they can influence the test result. It receives an ExtendedContext
object like beforeEach
and afterEach
.
import { onTestFinished, test } from 'vitest'
test('performs a query', () => {
const db = connectDb()
onTestFinished(() => db.close())
db.query('SELECT * FROM users')
})
WARNING
If you are running tests concurrently, you should always use onTestFinished
hook from the test context since Vitest doesn't track concurrent tests in global hooks:
import { test } from 'vitest'
test.concurrent('performs a query', ({ onTestFinished }) => {
const db = connectDb()
onTestFinished(() => db.close())
db.query('SELECT * FROM users')
})
This hook is particularly useful when creating reusable logic:
// this can be in a separate file
function getTestDb() {
const db = connectMockedDb()
onTestFinished(() => db.close())
return db
}
test('performs a user query', async () => {
const db = getTestDb()
expect(
await db.query('SELECT * from users').perform()
).toEqual([])
})
test('performs an organization query', async () => {
const db = getTestDb()
expect(
await db.query('SELECT * from organizations').perform()
).toEqual([])
})
TIP
This hook is always called in reverse order and is not affected by sequence.hooks
option.
onTestFailed
This hook is called only after the test has failed. It is called after afterEach
hooks since they can influence the test result. It receives an ExtendedContext
object like beforeEach
and afterEach
. This hook is useful for debugging.
import { onTestFailed, test } from 'vitest'
test('performs a query', () => {
const db = connectDb()
onTestFailed((e) => {
console.log(e.result.errors)
})
db.query('SELECT * FROM users')
})
WARNING
If you are running tests concurrently, you should always use onTestFailed
hook from the test context since Vitest doesn't track concurrent tests in global hooks:
import { test } from 'vitest'
test.concurrent('performs a query', ({ onTestFailed }) => {
const db = connectDb()
onTestFailed((result) => {
console.log(result.errors)
})
db.query('SELECT * FROM users')
})