What is nise?
The nise npm package is a library for creating fake servers, responses, and timers in JavaScript tests. It allows developers to simulate server responses and time-based behavior without the need for an actual server or waiting for real time to pass. This is particularly useful in unit testing, where tests need to be both fast and deterministic.
What are nise's main functionalities?
Fake XMLHttpRequest and server
This feature allows you to create a fake server that can respond to XMLHttpRequests. You can specify the HTTP method, URL, and response details. This is useful for testing AJAX requests without needing to hit a real server.
var fakeServer = nise.fakeServer.create();
fakeServer.respondWith('GET', '/some/article', [200, { 'Content-Type': 'application/json' }, '{ "id": 12, "comment": "Hey there" }']);
fakeServer.respondImmediately = true;
Fake timers
With fake timers, you can simulate the passage of time in tests. This is useful for functions that rely on setTimeout, setInterval, or Date objects. It allows you to test time-dependent code without real time delays.
var clock = nise.useFakeTimers();
clock.tick(1000); // Simulate the passage of 1 second
Other packages similar to nise
sinon
Sinon is a popular testing library that includes functionalities similar to nise, such as spies, stubs, mocks, and fake servers. While nise focuses on network requests and timers, Sinon provides a broader range of testing utilities, making it a more comprehensive solution for many testing scenarios.
nock
Nock is a powerful HTTP server mocking and expectations library for Node.js. Unlike nise, which provides both fake servers and timers, nock focuses exclusively on intercepting and mocking HTTP requests. It allows for a more detailed and flexible setup of request interception, making it a strong choice for testing HTTP interactions.