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Steven Liao
Steven Liao

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Jest for Sinon Stubs

#testing #javascript #jest #sinon

At work, we recently converted from Mocha, Karma, Chai, and Sinon to Jest. It was not immediately obvious what the direct replacement was for

sinon.stub(object, 'methodName').callsFake(() => {})
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Found out Jest provides similar functionality with

jest.spyOn(object, 'methodName').mockImplementation(() => {})
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Top comments (7)

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afsarzan profile image
Afsar •

How to handle it if there is callback ?

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2ezpz2plzme profile image
Steven Liao •

What callback are you talking about? Got an example?

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afsarzan profile image
Afsar • 
sinon.stub(object, 'methodName').callsFake((param,cb) => {
cb(param);
})
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2ezpz2plzme profile image
Steven Liao • 
jest.spyOn(object, 'methodName').mockImplementation((param, cb) => {
  cb(param)
})
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Does that work?

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afsarzan profile image
Afsar •

No. It says this expression is not callable. cb: unknow param

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hellixum profile image
SANKALP PANDEY •

ThankYou very much... I have been looking for this exact thing for hours on internet
.... you saved my day

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danieldfc profile image
Daniel Felizardo •

Thank you very much, I spent a lot of time trying to figure out how to solve this kind of problem.
Here's the solution.