mocks - how to verify private method was called

Question

I am trying to mock a private method and verify it has been executed.
The mocking itself works fine, that is I am getting correct results whether I comment/uncomment the 'when' line. However, I am having troubles with verification.

@RunWith(PowerMockRunner.class)
@PrepareForTest(ClassToTest.class)
public class TestClass {

    @Test
    public void test() throws Exception {
        ClassToTest spy = PowerMockito.spy(new ClassToTest());
        when(spy, method(ClassToTest.class, "privMethod", int.class)).withArguments(anyInt()).thenReturn(20);
        System.out.println(spy.pubMethod());
        PowerMockito.verifyPrivate(spy, times(1)).invoke("privMethod", int.class);
    }
}

class ClassToTest {

    public int pubMethod() {
        return privMethod(231);
    }

    private int privMethod(int whatever) {
        return 10;
    }
}

created this example based on https://code.google.com/p/powermock/wiki/MockitoUsage13 This is what I am getting, any idea why?

java.lang.IllegalArgumentException: argument type mismatch
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.powermock.reflect.internal.WhiteboxImpl.performMethodInvocation(WhiteboxImpl.java:1873)
    at org.powermock.reflect.internal.WhiteboxImpl.doInvokeMethod(WhiteboxImpl.java:773)
    at org.powermock.reflect.internal.WhiteboxImpl.invokeMethod(WhiteboxImpl.java:638)
    at org.powermock.reflect.Whitebox.invokeMethod(Whitebox.java:401)
    at org.powermock.api.mockito.internal.verification.DefaultPrivateMethodVerification.invoke(DefaultPrivateMethodVerification.java:39)
    at test.TestClass.test(TestClass.java:24)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:69)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:310)
    at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:89)
    at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:96)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:294)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:128)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:283)
    at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:91)
    at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:49)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:208)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:121)
    at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:34)
    at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:45)
    at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:123)
    at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:104)
    at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53)
    at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:53)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:684)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:391)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

Answer 1

Instead of int.class, verify the argument value 231. Mock verification works by matching values, not types (unless you use the argument matchers as in your when part).