@types/jest

What is @types/jest?

The @types/jest package provides TypeScript type definitions for Jest, a popular JavaScript testing framework. This allows developers to use Jest in TypeScript projects with type checking and IntelliSense support for Jest's API.

What are @types/jest's main functionalities?

Type Definitions for Jest Functions

Provides type definitions for Jest's global functions like 'test' and 'expect', enabling type checking and autocompletion in TypeScript.

test('adds 1 + 2 to equal 3', () => {
  expect(1 + 2).toBe(3);
});

Type Definitions for Matchers

Includes type definitions for Jest's matchers, such as 'toMatch', 'toBe', and 'toHaveProperty', ensuring correct usage with TypeScript.

expect('hello').toMatch(/hello/);

Type Definitions for Mock Functions

Provides type definitions for Jest's mock functions and their methods like 'mockReturnValue' and 'mockImplementation'.

const mockFunction = jest.fn();
mockFunction.mockReturnValue('default value');

Type Definitions for Jest Configuration

Offers type definitions for Jest configuration options, which can be used when setting up Jest in a TypeScript project.

const jestConfig = {
  verbose: true,
  collectCoverage: true
};

Other packages similar to @types/jest

@types/mocha

Provides TypeScript type definitions for Mocha, another testing framework. Similar to @types/jest, it allows developers to use Mocha with TypeScript's type checking.

@types/chai

Offers type definitions for Chai, an assertion library that can be used with testing frameworks like Mocha. It serves a similar purpose to @types/jest but for Chai's API.

@types/sinon

Contains TypeScript type definitions for Sinon, a library for spies, stubs, and mocks in JavaScript tests. It is similar to the mock functionality provided by Jest and its type definitions in @types/jest.

README

Installation

npm install --save @types/jest

Summary

This package contains type definitions for Jest (https://jestjs.io/).

Details

Files were exported from https://github.com/DefinitelyTyped/DefinitelyTyped/tree/master/types/jest.

Additional Details

• Last updated: Tue, 10 Aug 2021 18:31:27 GMT
• Dependencies: @types/jest-diff, @types/pretty-format
• Global values: afterAll, afterEach, beforeAll, beforeEach, describe, expect, fail, fdescribe, fit, it, jasmine, jest, pending, spyOn, test, xdescribe, xit, xtest

Credits

These definitions were written by Asana (https://asana.com) // Ivo Stratev, jwbay, Alexey Svetliakov, Alex Jover Morales, Allan Lukwago, Ika, Waseem Dahman, Jamie Mason, Douglas Duteil, Ahn, Josh Goldberg, Jeff Lau, Andrew Makarov, Martin Hochel, Sebastian Sebald, Andy, Antoine Brault, Gregor Stamać, ExE Boss, Alex Bolenok, Mario Beltrán Alarcón, Tony Hallett, Jason Yu, Devansh Jethmalani, Pawel Fajfer, Regev Brody, Alexandre Germain, and Adam Jones.