使用Mockito调用super.method（）

Question

First of all I would like to say I am working with legacy code and I cannot change it no matter how much I want to.

With that out the way, what I am trying to do is verify that a super.method() is called. This is specifically what I am trying to test with Mockito/Junit:

class foo extends JApplet(){

       public void destroy(){
          super.destroy();
 }
}

Normally something like this would suffice in a test case if it was not a super method being called:

verify(foo).destroy();

I've seen this question asked a couple of times and usually the response is "Inheritance is bad, change your code" which I cannot do at all unfortunately. Is anyone aware of any frameworks or small little tricks I could do to test this?

Thanks in advance - I know this is a tricky problem!

Answer 1

You can refactor the code to call the super method in some other method like:

      class foo extends JApplet(){

       public void destroy(){
          callSuperDestroy();
       }
       public void callSuperDestroy(){
           super.destroy();
       }}

And then verify:

verify(foo).callSuperDestroy();

Answer 2

It appears that JMockit might be able to do this. Check out this post:

Powermock - mocking a super method invocation

Answer 3

I haven't tried this, but isn't it possible to create a custom ClassLoader which overrides loading of JApplet class only? Then you can create your own JApplet, which remembers whether destroy() is called.

Answer 4

What you actually need to test is that the effect of invoking the super-method still hold true. The fact that the easiest way to achieve this is via invoking the super-method is simply a design detail.

With this in mind:

1. Write a test for the super-method.
2. Write a test for your sub-method, and also invoke the test for the super-method on the same class from within this test (either by direct invocation, or by subclassing the test).