This module provides Jest compatible expect assertion functionality.
import { expect } from "@std/expect"; const x = 6 * 7; expect(x).toEqual(42); expect(x).not.toEqual(0); await expect(Promise.resolve(x)).resolves.toEqual(42);
Currently this module supports the following functions:
toBe
toEqual
toStrictEqual
toMatch
toMatchObject
toBeDefined
toBeUndefined
toBeNull
toBeNaN
toBeTruthy
toBeFalsy
toContain
toContainEqual
toHaveLength
toBeGreaterThan
toBeGreaterThanOrEqual
toBeLessThan
toBeLessThanOrEqual
toBeCloseTo
toBeInstanceOf
toThrow
toHaveProperty
toHaveBeenCalled
toHaveBeenCalledTimes
toHaveBeenCalledWith
toHaveBeenLastCalledWith
toHaveBeenNthCalledWith
toHaveReturned
toHaveReturnedTimes
toHaveReturnedWith
toHaveLastReturnedWith
toHaveNthReturnedWith
expect.addSnapshotSerializer
expect.assertions
expect.addEqualityTester
expect.extend
expect.hasAssertions
Only these functions are still not available:
toMatchSnapshot
toMatchInlineSnapshot
toThrowErrorMatchingSnapshot
toThrowErrorMatchingInlineSnapshot
The tracking issue to add support for unsupported parts of the API is https://github.com/denoland/std/issues/3964.
This module is largely inspired by x/expect module by Allain Lalonde.
Add Package
deno add jsr:@std/expect
Import symbol
import * as expect from "@std/expect";
---- OR ----
Import directly with a jsr specifier
import * as expect from "jsr:@std/expect";
Add Package
npx jsr add @std/expect
Import symbol
import * as expect from "@std/expect";
Add Package
yarn dlx jsr add @std/expect
Import symbol
import * as expect from "@std/expect";
Add Package
pnpm dlx jsr add @std/expect
Import symbol
import * as expect from "@std/expect";
Add Package
bunx jsr add @std/expect
Import symbol
import * as expect from "@std/expect";