Mockito: mocking an arraylist that will be looped in a for loop

Question

I have a method under test that contains the following snippet:

private void buildChainCode(List lines){
    for(TracedPath path : lines){
             


        

Answer 1

Your problem is that when you use a collection in a for-each loop, its iterator() method gets called; and you haven't stubbed that particular method.

Instead of mocking the list, I strongly recommend you just pass a real list, where the elements are just your mocked TracedPath, as many times as you want it. Something like

listOfPaths = Arrays.asList(mockTracedPath, mockTracedPath, mockTracedPath);