@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 (http://facebook.github.io/jest/).

Details

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

Additional Details

• Last updated: Wed, 11 Apr 2018 19:11:59 GMT
• Dependencies: none
• 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 https://github.com/NoHomey, jwbay https://github.com/jwbay, Alexey Svetliakov https://github.com/asvetliakov, Alex Jover Morales https://github.com/alexjoverm, Allan Lukwago https://github.com/epicallan, Ika https://github.com/ikatyang, Waseem Dahman https://github.com/wsmd, Jamie Mason https://github.com/JamieMason, Douglas Duteil https://github.com/douglasduteil, Ahn https://github.com/AhnpGit, Josh Goldberg https://github.com/joshuakgoldberg, Bradley Ayers https://github.com/bradleyayers.