how to unit test this.getView().setModel()

I have SAPUI5 app that I'm trying to unit test using QUnit.

The code I'm trying to test is the following.

myFunction: function(flag, obj){
    var myModel = new sap.ui.model.json.JSONModel();

    if(flag){
        pricingModel.loadData("filePath", null, false);
    }
    ....
   obj.getView().setModel(myModel, "myModel");
   }

this function is located on a different file than my controller and is called from my controller like this.

  ...
  previous logic sets flag = true;
   ... 
   dataConnector.myFunction(flag, this); //where 'this' is the reference to he Main this of the application

Here is my unit test snippet

       QUnit.test("Valid NSN Input", function(assert) {
            // Arrange  
            var validInputEvent = {
                getParameters: sinon.stub().returns({ value: '306018040' })
            }; 

            var getValue = sinon.stub().returns('306018040');
            var setValue = sinon.spy();
            var apply = sinon.stub();                


            var controls = {


                dataConnectionFlag: true,

                nsnSearchInput : {
                    getValue: getValue,
                    setValue: setValue
                },
            };

            //Checking onFilterNSN when input has a valid value
            mainController.onSearch(validInputEvent, controls);

So to clarify everything above, I'm calling a function located on file.js from controller.js and passing in the 'this' reference so I can set my data model with that other file. Everything works fine when I run the application but the unit test fails as it doesn't know what the 'this' reference is. Is there a way to make this test work?