chai-jest/README.md

Chai bindings for jest mocks.

# chai-jest

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## Description

Adds functions for testing Jest mocks to chai.

If you're using `chai` with jest, but you still want access to the mock-related
functions on jest's `expect` such as `toHaveBeenCalled()`, then this is for you.

## Usage

```ts
import chai from 'chai';
import chaiJest from 'chai-jest';

chai.use(chaiJest);
const { expect } = chai;

describe('My test suite', () => {
    it('should test a jest mock', () => {
        const mock = jest.fn(() => true);

        mock();

        expect(mock).to.have.beenCalled;
        expect(mock).to.have.returnedWith(true);
    });
});
```

## Assertions

- beenCalled
- beenCalledWith(...args: unknown[])
- beenLastCalledWith(...args: unknown[])
- beenNthCalledWith(nthCall: number, ...args: unknown[])
- beenCalledTimes(times: number)
- returned
- returnedTimes(count: number)
- returnedWith(expected: unknown)
- lastReturnedWith(expected: unknown)
- nthReturnedWith(nthCall: number, expected: unknown)

Copyright 2020 Jason Walton