@types/fetch-mock

What is @types/fetch-mock?

@types/fetch-mock provides TypeScript type definitions for the fetch-mock library, which is used to mock HTTP requests in tests. This allows developers to simulate different responses from the fetch API, making it easier to test how their code handles various scenarios.

What are @types/fetch-mock's main functionalities?

Mocking a simple GET request

This feature allows you to mock a simple GET request. The code sample shows how to mock a GET request to '/api/data' and return a JSON object with sample data.

const fetchMock = require('fetch-mock');
fetchMock.get('/api/data', { data: 'sample data' });

fetch('/api/data').then(response => response.json()).then(data => console.log(data));

Mocking a POST request with specific body

This feature allows you to mock a POST request with a specific request body. The code sample shows how to mock a POST request to '/api/submit' and return different responses based on the request body.

fetchMock.post('/api/submit', (url, options) => {
  if (options.body === JSON.stringify({ name: 'test' })) {
    return { status: 'success' };
  } else {
    return { status: 'error' };
  }
});

fetch('/api/submit', { method: 'POST', body: JSON.stringify({ name: 'test' }) })
  .then(response => response.json())
  .then(data => console.log(data));

Mocking with delay

This feature allows you to mock a request with a delay. The code sample shows how to mock a GET request to '/api/delayed' and return a response after a 1-second delay.

fetchMock.get('/api/delayed', new Promise(resolve => setTimeout(() => resolve({ data: 'delayed data' }), 1000)));

fetch('/api/delayed').then(response => response.json()).then(data => console.log(data));

Restoring fetch to its original state

This feature allows you to restore the fetch function to its original state after mocking. The code sample shows how to mock a GET request and then restore the fetch function.

fetchMock.get('/api/data', { data: 'sample data' });
fetchMock.restore();

fetch('/api/data').then(response => response.json()).then(data => console.log(data));

Other packages similar to @types/fetch-mock

nock

Nock is a HTTP mocking and expectations library for Node.js. It allows you to intercept HTTP requests and mock responses. Compared to fetch-mock, Nock is more focused on Node.js and provides a more extensive set of features for mocking HTTP requests.

msw

Mock Service Worker (MSW) is a library for mocking network requests in both browser and Node.js environments. It uses Service Worker API to intercept requests and provides a more modern approach to mocking compared to fetch-mock. MSW is particularly useful for testing in browser environments.

axios-mock-adapter

Axios Mock Adapter is a library that allows you to easily mock requests made with axios. It provides a simple API for defining mock responses for different HTTP methods. Compared to fetch-mock, axios-mock-adapter is specifically designed for use with the axios library.

README

Installation

npm install --save @types/fetch-mock

Summary

This package contains type definitions for fetch-mock (https://github.com/wheresrhys/fetch-mock).

Details

Files were exported from https://github.com/DefinitelyTyped/DefinitelyTyped/tree/master/types/fetch-mock.

Additional Details

• Last updated: Tue, 07 Nov 2023 20:08:00 GMT
• Dependencies: none

Credits

These definitions were written by Alexey Svetliakov, Tamir Duberstein, Risto Keravuori, Chris Sinclair, Matt Tennison, Quentin Bouygues, Fumiaki Matsushima, Colin Doig, Felix Chen, and Katsuya Hino.