sinon

What is sinon?

Sinon is a testing utility that provides functions for spies, stubs, and mocks, which are essential for behavior-driven development and testing in JavaScript. It works with any unit testing framework and is widely used for its versatile API and comprehensive feature set.

What are sinon's main functionalities?

Spies

Spies are functions that record their usage, such as how many times they were called, with what arguments, and what was returned. They can be used to wrap existing functions to add this tracking ability.

const sinon = require('sinon');
const myFunction = sinon.spy();
myFunction('Hello', 'World');
console.log(myFunction.calledOnce); // true

Stubs

Stubs are like spies, but they can replace the target function's behavior, either by returning a specific value or by throwing an exception. They are useful for controlling a function's behavior in a test.

const sinon = require('sinon');
const myObj = { myMethod: () => 'original' };
const stub = sinon.stub(myObj, 'myMethod').returns('stubbed');
console.log(myObj.myMethod()); // 'stubbed'

Mocks

Mocks are fake methods (like stubs) with pre-programmed behavior and expectations. They are used to assert that certain methods are called in certain ways.

const sinon = require('sinon');
const myObj = { myMethod: () => 'original' };
const mock = sinon.mock(myObj);
mock.expects('myMethod').once().returns('mocked');
console.log(myObj.myMethod()); // 'mocked'
mock.verify();

Other packages similar to sinon

jest

Jest is a complete testing framework that comes with spies, mocks, and stubs built-in. It is often compared to Sinon for its mocking capabilities, but Jest provides a more integrated experience with a test runner and assertion library included.

testdouble

Testdouble.js (npm package 'testdouble') is a minimalistic testing library that provides a similar API to Sinon for creating test doubles like stubs, mocks, and spies. It focuses on providing a more user-friendly experience with better error messages and simpler APIs.

chai-spies

Chai-spies is a plugin for the Chai assertion library that adds spy capabilities. While it doesn't offer as comprehensive a set of features as Sinon, it integrates well with Chai for developers who prefer that assertion style.

README

Sinon.JS

Standalone and test framework agnostic JavaScript test spies, stubs and mocks (pronounced "sigh-non", named after Sinon, the warrior).

Compatibility

For details on compatibility and browser support, please see COMPATIBILITY.md

Installation

via npm

$ npm install sinon

or via Sinon's browser builds available for download on the homepage. There are also npm based CDNs one can use.

Usage

See the sinon project homepage for documentation on usage.

If you have questions that are not covered by the documentation, you can check out the sinon tag on Stack Overflow.

Goals

• No global pollution
• Easy to use
• Require minimal “integration”
• Easy to embed seamlessly with any testing framework
• Easily fake any interface
• Ship with ready-to-use fakes for XMLHttpRequest, timers and more

Contribute?

See CONTRIBUTING.md for details on how you can contribute to Sinon.JS

Backers

Thank you to all our backers! 🙏 [Become a backer]

Sponsors

Become a sponsor and get your logo on our README on GitHub with a link to your site. [Become a sponsor]

Licence

Sinon.js was released under BSD-3

Changelog

17.0.2

• f6dca0ba upgrade packages (#2595) (Carl-Erik Kopseng)
• 5025d001 Avoid return and callArg* clearing each other's state (#2593) (Carl-Erik Kopseng)

  • Partially revert "fix returns does not override call through (#2567)"

  • revert to the old manual clearing of props

• ed068a88 Bump ip from 1.1.8 to 1.1.9 (#2587) (dependabot[bot])
• ec4d592e fix #2589: avoid invoking getter as side-effect (#2592) (Carl-Erik Kopseng)
• 9972e1e3 Fix typo in mocks documentation (#2591) (Eduardo de la Cruz Palacios)
• 52e6e4c5 chore: prefer cache option of setup-node (Morgan Roderick)
• 08da1235 Bump actions/cache from 3 to 4 (dependabot[bot])
• 404ef47e Bump nokogiri from 1.14.3 to 1.16.2 (dependabot[bot])
• fd79612c Update Bug_report.md (Carl-Erik Kopseng)
• 1fbc812a Re-add about (Carl-Erik Kopseng)
• fc8f6c3e Fix formatting :clown: (Carl-Erik Kopseng)
• c57e38ae Remove old template (Carl-Erik Kopseng)
• 754bf7a9 Update Bug_report.md (Carl-Erik Kopseng)
• 87eed9d2 Fix some typos at code comments (#2581) (EliyahuMachluf)
• cbae6997 Link to createStubInstance util.md docs in stubs.md (#2577) (Daniel Kaplan)
• adcf936d Fix Mocha watch task by delegating to Node (#2573) (Carl-Erik Kopseng)
• 30ad2372 prettier:write (Carl-Erik Kopseng)
• 45c4d6b9 Remove outdated info from README (#2571) (Carl-Erik Kopseng)
• 6c9f5c2a Add a notice that the Fake Timers API doc is incomplete (#2570) (Carl-Erik Kopseng)
• 93db3ef3 breaking: Remove sinon.defaultConfig and related modules (#2565) (Carl-Erik Kopseng)

  • breaking: Remove sinon.defaultConfig and related modules

  default-config and get-config are leftovers from when Sinon

  shipped with sinon.test (now the independent NPM module

  'sinon-test').

Released by Carl-Erik Kopseng on 2024-05-07.