PowerMockito verifyTimes Always passets private method

Question

public class TestedClass
{
    
    public void publicMethod() 
    {
        privateMethod();
    }
    
    private void privateMethod() 
    {
    }
}

I would like to test with PowerMockito that the private method is called exactly once.

Here's my test class:

@RunWith(PowerMockRunner.class)
@PowerMockIgnore("javax.management.*")
public class TestedClassTest
{
    
    @Before
    public void setUp()
    {
    }
    
    @Test
    public void testPrivateMethodCalledOnce() throws Exception 
    {
        TestedClass spy = PowerMockito.spy(new TestedClass());
        spy.publicMethod();
        
        PowerMockito.verifyPrivate(spy, Mockito.times(772)).invoke("privateMethod"); 
    }
}

Despite only being called once this test passes. Even if I comment privateMethod inside the public method the test seems too pass.

public class TestedClass
{

    public void publicMethod() 
    {
        //privateMethod(); <-- test still passes
    }

    private void privateMethod() 
    {
    }
}

Does anyone have an idea what I did wrong? And does anyone know how to verify that the private method was called exactly once in the unit test?

Does this answer your question? [Powermock verify private static method call in non static method](https://stackoverflow.com/questions/16515809/powermock-verify-private-static-method-call-in-non-static-method) — Progman, Dec 22 '21 at 19:41

xerx593 · Answer 1 · 2021-12-23T12:35:02.747

1

The problem could be is, that:

.invoke("privateMethod")

can be interpreted as:

void invoke(String methodToVerify, Object... arguments) javadoc, which we (obviously) want. Or
void invoke(Object... arguments) javadoc, which is different and discovers the (private) method not by name, but by "arguments".

So a solution could be (to avoid incorrect overload):

.invoke("privateMethod", new Object[0]) // which still *could* be 
   // confused with Object... but I "hope" the String in front saves us!:)
// if this works: .invoke("privateMethod", null) should also work.

Or to use one of the alternatives corerctly.#

But this is often the problem with "overloaded libs" ... varargs makes things even worse/potentially in-deterministic! :-)

edited Dec 23 '21 at 12:35

answered Dec 22 '21 at 19:48

xerx593

12,237
5
33
64

@all: Watch out for (Power)Mockito method (matchers/verifiers) overloads!! – xerx593 Dec 22 '21 at 19:54
1

thanks for replying. Really learned from your example. In this case it seems as the "@PrepareForTest" annotation was missing in the test. – STSISA Dec 23 '21 at 12:01
Actually I was completely wrong! :-):-):-) Thank You anyway! – xerx593 Dec 23 '21 at 12:49
well I learned something new and also you didn't give me a lecture on why it's wrong to test a private class =). Thanks anyway – STSISA Dec 23 '21 at 13:10

score 1 · Answer 2 · answered Dec 23 '21 at 12:10

It seems as if I need to include the @PrepareForTest annotation in this particular test to make it work. Now the test fails which it was supposed to do. Also - it works when I change to Mockito.times(1).

@RunWith(PowerMockRunner.class)
@PowerMockIgnore("javax.management.*")
@PrepareForTest(TestedClass.class) // <--- I didn't include this in the question
public class TestedClassTest
{
    
    @Before
    public void setUp()
    {
    }
    
    @Test
    public void testPrivateMethodCalledOnce() throws Exception 
    {
        TestedClass spy = PowerMockito.spy(new TestedClass());
        spy.publicMethod();
        
        PowerMockito.verifyPrivate(spy, Mockito.times(1)).invoke("privateMethod"); 
    }
}

PowerMockito verifyTimes Always passets private method

2 Answers2