mock method calling callback function sinon

javascript sinon
Stanley picture Stanley · May 24, 2017 · Viewed 9.4k times · Source

How do you mock an outer method calling a callback using sinon? Example given the following code, getText should return 'a string' as response in the callback function

sinon.stub(a, 'getText').returns('a string')
let cb = function(err, response) {
   console.log(response)
}
a.getText('abc', cb)

and it should produce the output 'a string' since it calls callback function cb but there is no output

Answer

robertklep picture robertklep · May 24, 2017 
sinon.stub(a, 'getText').yields(null, 'a string');

yields() will call the first function argument that gets passed to the stubbed function with the arguments provided (null, 'a string').

Related questions

Cleaning up sinon stubs easily

Is there a way to easily reset all sinon spys mocks and stubs that will work cleanly with mocha's beforeEach blocks. I see sandboxing is an option but I do not see how you can use a sandbox for this …

Read More
Stubbing a class method with Sinon.js

I am trying to stub a method using sinon.js but I get the following error: Uncaught TypeError: Attempted to wrap undefined property sample_pressure as function I also went to this question (Stubbing and/or mocking a class in …

Read More
How to mock localStorage in JavaScript unit tests?

Are there any libraries out there to mock localStorage? I've been using Sinon.JS for most of my other javascript mocking and have found it is really great. My initial testing shows that localStorage refuses to be assignable in firefox (…

Read More