How to use StackTraceFilter method of org.mockito.internal.exceptions.stacktrace.StackTraceFilterTest class

Further reading has led me to try using ArgumentCaptors and the following works, although much more verbose than I would like.

ArgumentCaptor<String> argument = ArgumentCaptor.forClass(String.class);

verify(errors, atLeastOnce()).add(argument.capture(), any(ActionMessage.class));

List<String> values = argument.getAllValues();

assertTrue(values.contains("exception.message"));
assertTrue(values.contains("exception.detail"));

PowerMock implements its own MockMaker which leads to incompatibility with Mockito mock-maker-inline, even if PowerMock is just added as a dependency and not used. If two org.mockito.plugins.MockMaker exist in path then any only one can be used, which one is undetermined.

PowerMock can however delegate calls to another MockMaker, and for then tests are run without PowerMock. Since PowerMock 1.7.0 this can be configured with using the PowerMock Configuration.

The MockMaker can be configured by creating the file org/powermock/extensions/configuration.properties and setting:

mockito.mock-maker-class=mock-maker-inline

Example of using Mockito mock-maker-inline with PowerMock: https://github.com/powermock/powermock-examples-maven/tree/master/mockito2

The problem is, you cannot mix argument matchers and real arguments in a mocked call. So, rather do this:

when(serviceValidatorStub.validate(
    any(),
    isA(UserCommentRequestValidator.class),
    eq(UserCommentResponse.class),
    eq(UserCommentError.class))
).thenReturn(new UserCommentResponse());

Notice the use of the eq() argument matcher for matching equality.

see: https://static.javadoc.io/org.mockito/mockito-core/1.10.19/org/mockito/Matchers.html#eq(T)

Also, you could use the same() argument matcher for Class<?> types - this matches same identity, like the == Java operator.

It is quite easy with Mockito:

@RunWith(MockitoJUnitRunner.class)
public class RuleIdValidatorTest {
    @Mock
    private RuleStore ruleStoreMock;

    @InjectMocks
    private RuleIdValidator ruleIdValidator;

    @Test
    public void someTest() {
        when(ruleStoreMock.doSomething("arg")).thenReturn("result");

        String actual = ruleIdValidator.doSomeThatDelegatesToRuleStore();

        assertEquals("result", actual);
    }
}

Read more about @InjectMocks in the Mockito javadoc or in a blog post that I wrote about the topic some time ago.

Available as of Mockito 1.8.3, enhanced in 1.9.0.

You could use a custom answer to do this

MyInterface myMock = mock(MyInterface.class);
Sky sky = buildRandomSkyColor();

when(myMock.methodWithNoArguments()).thenAnswer(new Answer<String>(){
    String answer(InvocationOnMock invocation) {
        if(sky.isBlue())
            return "blue";
        else
            return "gray";
    }
}

This took me a while to figure out, so I am answering my own question.

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mockito;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)  // important
@PrepareForTest(MachineImpl.class)  // important: do not use Thread.class here
public class MachineImplTest {

    private MachineImpl classUnderTest;

    @Before
    public void beforeEachTest() {
        classUnderTest = new MachineImpl();
    }

    @Test
    public void sleep_Pass() {
        classUnderTest.sleep(0);
        classUnderTest.sleep(-100);
        classUnderTest.sleep(+100);
    }

    @Test
    public void sleep_Pass2() {
        // We do not want to mock all methods, only specific methods, such as Thread.sleep().
        // Use spy() instead of mockStatic().
        PowerMockito.spy(Thread.class);

        // These two lines are tightly bound.
        PowerMockito.doThrow(new InterruptedException()).when(Thread.class);
        Thread.sleep(Mockito.anyLong());

        classUnderTest.sleep(0);
        classUnderTest.sleep(-100);
        classUnderTest.sleep(+100);
    }
}

If you are using TestNG, try this:

import org.mockito.Mockito;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.testng.PowerMockTestCase;

@PrepareForTest(MachineImpl.class)  // important: do not use Thread.class here
public class MachineImplTest
extends PowerMockTestCase {
    ...
}

Read more about TestNG + Mockito + PowerMock here: https://stackoverflow.com/a/35815153/257299

The two syntaxes for stubbing are roughly equivalent. However, you can always use doReturn/when for stubbing; but there are cases where you can't use when/thenReturn. Stubbing void methods is one such. Others include use with Mockito spies, and stubbing the same method more than once.

One thing that when/thenReturn gives you, that doReturn/when doesn't, is type-checking of the value that you're returning, at compile time. However, I believe this is of almost no value - if you've got the type wrong, you'll find out as soon as you run your test.

I strongly recommend only using doReturn/when. There is no point in learning two syntaxes when one will do.

You may wish to refer to my answer at Forming Mockito "grammars" - a more detailed answer to a very closely related question.

Unfortunately I can't tell you why this happened, but I can tell you how to get around this issue.

The problem was, that PowerMockito scanned tha class path and also added the RESTeasy classes (which are located within the package 'javax.ws.*'. Therefor the above mentioned RuntimeDelegate was loaded by the PowerMockito classloader and caused later the issue, that the class was compared against one from a different classloader.

To get around this issue, tell PowerMockito to ignore the javax.ws package when scanning for classes:

@PowerMockIgnore({"javax.ws.*"})

@Test
public void persistGenericModelsAsync() throws JsonProcessingException {

    //stubbed - but never used
    when(restTemplate.exchange(Mockito.anyString(), Mockito.eq(HttpMethod.POST), Mockito.any(HttpEntity.class), Mockito.eq(JsonNode.class))).thenReturn(response);

    //stubbed - but never used
    when(response.getHeaders()).thenReturn(headers);
    List<String> cookiesTest = Arrays.asList("TxCartIdtest", "test");
    //stubbed - but never used
    when(headers.get(ValueConstant.SET_COOKIE)).thenReturn(cookiesTest);
    //stubbed - but never used
    when(response.getBody()).thenReturn(jsonNode);
}

Its clear that, none of the stubs you created with when() is getting used any where. For Eg. , the first stub where you return a response object - you have never used a call to restTemplate.exchange() any where in test execution of this method.

When you use the strict stubbing mode, you need to make sure - you use any stub that you create. See more here