velt/test

API reference

The test runner, written in Velt, with Vitest's API; import ... from "vitest" imports this module too. velt test (Testing) compiles the test files into a program whose generated main registers their tests with this module and hands it control. For a walkthrough, read the guide.

import { describe, it, expect } from "velt/test";

Exports

expectThe matchers for actual.afterAllRuns fn once after the last test of the group (or file) that runs in this process; a group's afterAll hooks run last-registered first, as Vitest's.afterEachRuns fn after each test of the group (or file), inner groups' first, also after a failure; a group's afterEach hooks run last-registered first, as Vitest's.beforeAllRuns fn once before the first test of the group (or file) that runs in this process.beforeEachRuns fn before each test of the group (or file), outer groups' first.describeA group of tests: fn runs when the file's tests are collected, and the tests and hooks it registers belong to the group.itA test: fn, sync or async, passes unless it throws (or its promise rejects).testit.ExpectWhat expect(actual) returns: the matchers for actual.SettlesWhat a test or hook callback returns: nothing, or a promise, which is awaited.

function

expect

#std/test/expect.vlt:103

Re-exported from velt/test/expect

function expect<T>(actual: T): Expect<T>

The matchers for actual.

function

afterAll

#std/test/suite.vlt:207

Re-exported from velt/test/suite

function afterAll<R extends Settles>(fn: () => R throws unknown)

Runs fn once after the last test of the group (or file) that runs in this process; a group's afterAll hooks run last-registered first, as Vitest's.

function

afterEach

#std/test/suite.vlt:226

Re-exported from velt/test/suite

function afterEach<R extends Settles>(fn: () => R throws unknown)

Runs fn after each test of the group (or file), inner groups' first, also after a failure; a group's afterEach hooks run last-registered first, as Vitest's.

function

beforeAll

#std/test/suite.vlt:196

Re-exported from velt/test/suite

function beforeAll<R extends Settles>(fn: () => R throws unknown)

Runs fn once before the first test of the group (or file) that runs in this process.

function

beforeEach

#std/test/suite.vlt:215

Re-exported from velt/test/suite

function beforeEach<R extends Settles>(fn: () => R throws unknown)

Runs fn before each test of the group (or file), outer groups' first.

function

describe

#std/test/suite.vlt:157

Re-exported from velt/test/suite

function describe<R extends Settles>(
  name: string,
  fn: () => R throws unknown,
)

A group of tests: fn runs when the file's tests are collected, and the tests and hooks it registers belong to the group. If it throws (or is async), none of the group's tests run: a test named as the group fails with the error.

function

it

#std/test/suite.vlt:183

Re-exported from velt/test/suite

function it<R extends Settles>(name: string, fn: () => R throws unknown)

A test: fn, sync or async, passes unless it throws (or its promise rejects).

function

test

#std/test/suite.vlt:191

Re-exported from velt/test/suite

function test<R extends Settles>(name: string, fn: () => R throws unknown)

it.

class

Expect

#std/test/expect.vlt:14

Re-exported from velt/test/expect

class Expect<T>

What expect(actual) returns: the matchers for actual.

Returned byexpect

readonly actual: T

The value under test.

readonly negated: bool

After .not: every matcher checks the opposite.

constructor(actual: T, negated: bool)No doc comment yet

get not(): Expect<T>

The same matchers, each checking the opposite.

check(pass: bool, message: string, notMessage?: string)

Fails the test with message unless pass. After .not, fails if pass, with notMessage (by default message with its first to written not to). Every matcher, built-in or added with extend, checks through this.

toBe(expected: T)

Object.is(actual, expected): the same value (NaN is NaN, 0 isn't -0).

toEqual(expected: T)

Deep equality, as Vitest's: contents, recursively, class instances by their fields (a Date by its time, a Set by its members in any order), numbers with Object.is (NaN equals itself, 0 doesn't equal -0).

toBeNull()

actual is null.

toBeUndefined()

actual is undefined.

toBeDefined()

actual is not undefined.

toBeTruthy()

Boolean(actual) is true.

toBeFalsy()

Boolean(actual) is false.

interface

Settles

#std/test/suite.vlt:21

Re-exported from velt/test/suite

What a test or hook callback returns: nothing, or a promise, which is awaited. it's callback returns a type with this bound, so a sync and an async callback both fit.

Used byafterAllafterEachbeforeAllbeforeEachdescribeittest

[ [SETTLE](): Promise<void, unknown>

Waits for it if it is a promise; its rejection is the callback's error.

[ [KIND](): string

"promise", "function" or "value".