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40 lines
882 B
Plaintext
40 lines
882 B
Plaintext
---
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{
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.title = "Jest mocks are ...different",
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.date = @date("2022-04-25T00:00:00"),
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.author = "koehr",
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.draft = false,
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.layout = "til.shtml",
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.description = "",
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.tags = [],
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}
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---
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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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