What is @types/chai?
The @types/chai package provides TypeScript type definitions for Chai, a BDD / TDD assertion library for node and the browser. This allows developers to use Chai in TypeScript projects with type checking and IntelliSense support in code editors.
What are @types/chai's main functionalities?
Expect/Should Assertions
Provides fluent API for asserting facts about values in a readable manner. Supports both 'expect' and 'should' styles.
expect(foo).to.be.a('string');
expect(foo).to.equal('bar');
expect(foo).to.have.lengthOf(3);
should.exist(foo);
foo.should.be.a('string');
foo.should.equal('bar');
Assert Style
Enables a more classical assert style, similar to node's assert module but with more capabilities.
assert.typeOf(foo, 'string');
assert.equal(foo, 'bar');
assert.lengthOf(foo, 3);
Property Assertions
Allows asserting the existence of an object's property, optionally asserting its value or properties.
expect(foo).to.have.property('length').with.lengthOf(3);
foo.should.have.property('length').with.lengthOf(3);
Other packages similar to @types/chai
@types/jest
Provides TypeScript definitions for Jest, a testing framework with a focus on simplicity. While Jest comes with its own assertion library, it's more tightly integrated with its testing environment compared to Chai, which is assertion library agnostic.
@types/mocha
Offers TypeScript definitions for Mocha, a feature-rich JavaScript test framework running on Node.js and in the browser. Mocha itself is more about the test framework rather than assertions, and it's often used in combination with Chai.
@types/sinon
Supplies TypeScript definitions for Sinon, a standalone test spies, stubs, and mocks for JavaScript. While not an assertion library, Sinon is commonly used alongside Chai for behavior verification in tests.
Installation
npm install --save @types/chai
Summary
This package contains type definitions for chai (http://chaijs.com/).
Details
Files were exported from https://github.com/DefinitelyTyped/DefinitelyTyped/tree/master/types/chai.
Additional Details
- Last updated: Thu, 01 Aug 2024 01:34:49 GMT
- Dependencies: none
Credits
These definitions were written by Bart van der Schoor, Andrew Brown, Olivier Chevet, Matt Wistrand, Shaun Luttin, Satana Charuwichitratana, Erik Schierboom, Bogdan Paranytsia, CXuesong, and Joey Kilpatrick.