CODEWITHSUNDEEP
javascriptunit-testingjasmine
williamsandonz
williamsandonz

Reputation: 16430

What are the shortcomings of javascript's revealing module pattern when unit testing with Jasmine?

What are the shortcomings of javascript's revealing module pattern when unit testing with Jasmine?

And what are the potential workarounds?

Upvotes: 0

Views: 1046

Answers (3)

ppoliani
ppoliani

Reputation: 4906

Basically the main caveat when you want to unit test a module (regardless of the test runner that is used) is the scope of the inner functions. That is, the inner methods; or if you will the private methods; are not accessible from outside of the module. Hence, it is not very obvious how to unit test those methods; This, of course, applies only in the case that you want to unit test your private methods.

I have written a blog post where this issue is described and a solution is proposed.

http://tech.pro/blog/1792/how-to-unit-test-private-functions-in-the-revealing-module-pattern

Upvotes: 1

Andreas Köberle
Andreas Köberle

Reputation: 110972

I'm using requireJS, which is a special kind of the module pattern, for over year now and cant see any shortcomings. Your module should use dependency injection so you can replace the dependencies of the module with mocks in your test. 

var myModule = (function(dep1){
  function someFancyAlgorythm(a){return a +1}
  return {
    foo: function(a){
      dep1(someFancyAlgorythm(a))
    }
  }
})(dep1)

in your test

describe('myModule',function(){

  var dep1;
  var module;

  beforeEach(function(){
   dep1 = jasmine.createSpy();
   module = myModule(dep1)
  })

  it('make crazy stuff', function(){
    module.foo(1);
    expect(dep1).toHaveBeenCalledWith(2);
  })
})

Upvotes: 4

rab
rab

Reputation: 4144

Could try this way 

var module = (function() {

    var priv = function(){

    };
    var pub = function(){

    };

    /**start-private-test**/
    pub._priv = priv ;
    /**end-private-test**/

    return {
        pub : pub
    }
}();

write test for pub._priv and production remove code unit private-test . for more information read this blog post

Upvotes: 1

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