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31 lines
734 B
Markdown
31 lines
734 B
Markdown
# Jest mocks are ...different
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If you want to mock an imported function in Jest in a way that allows you to check if it has been called, you can not do the seemingly straighforward:
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```js
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// mock prefix necessary btw
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const mockThatFunction = jest.fn(() => 'stuff')
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jest.mock('@/path/to/module', () => ({
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thatFunction: mockThatFunction,
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}))
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// ...in test descriptions
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expect(mockThatFunction).toHaveBeenCalled()
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```
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This way thatFunction will be undefined without anyone telling you why.
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What you need to do instead:
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```js
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import { thatFunction } from '@/path/to/module'
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jest.mock('@/path/to/module', () => ({
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thatFunction: jest.fn(() => 'stuff'),
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}))
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// ...in test descriptions
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expect(thatFunction).toHaveBeenCalled()
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```
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