Sinon JS

##Spies

//Anonymous function
var spy = sinon.spy();

//Provided Function
var spy = sinon.spy(myFunc);

//Existing object and function
var spy = sinon.spy(object, "method");

//Pass the spy as a function
PubSub.subscribe("message", spy);

Example -Spying on existing methods

//Spy on existing function
sinon.spy(jQuery, "ajax");

//Use function
jQuery.getJSON("/some/resource");

//Assert
expect(jQuery.ajax).to.have.been.called;

//Restore afterwards
jQuery.ajax.restore();

Stubs

Test stubs are functions (spies) with pre-programmed behavior.

Create Stubs

//Anonymous stub
var stub = sinon.stub();

//Replaces object.method with a stub function
var stub = sinon.stub(object, "method", func);
//Restore original method
stub.restore();

//Stub a whole object
var stub = sinon.stub(obj);

Instead of

sinon.assertCalledWith(mySpy, "foo");

call

expect(mySpy).to.have.been.calledWith("foo");