java - PowerMock 和 Mockito 的静态模拟不起作用

Question

我正在尝试验证 Collections.shuffle() 方法是否在我的一个类中被调用。我通读了有关 PowerMock 和 Mockito 的(小)文档，并通读了处理此问题但未得到解决的其他 SO 问题。

@RunWith(PowerMockRunner.class)
@PrepareForTest(Collections.class)
public class MyTest {

    @Test
    public void testShuffle() {
        PowerMockito.mockStatic(Collections.class);
        PowerMockito.doCallRealMethod().when(Collections.class);
        Collections.shuffle(Mockito.anyListOf(Something.class));

        ClassToTest test = new ClassToTest();
        test.doSomething();

        PowerMockito.verifyStatic(); // Verify shuffle was called exactly once
        Collections.shuffle(Mockito.anyListOf(Something.class));
    }
}

public class ClassToTest {
    private final List<Something> list;
    // ...
    public void doSomething() {
        Collections.shuffle(list);
        // do more stuff
    }
}

鉴于上面的代码，我希望单元测试通过。但是，单元测试失败如下:

Wanted but not invoked java.util.Collections.shuffle([]);
Actually, there were zero interactions with this mock.

我做错了什么？

谢谢

编辑:根据下面的建议，我尝试了以下操作，但我得到了同样的错误。

@RunWith(PowerMockRunner.class)
@PrepareForTest(Collections.class)
public class MyTest {

    @Test
    public void testShuffle() {
        PowerMockito.mockStatic(Collections.class);

        ClassToTest test = new ClassToTest();
        test.doSomething();

        PowerMockito.verifyStatic(); // Verify shuffle was called exactly once
        Collections.shuffle(Mockito.anyListOf(Something.class));
    }
}

Answer 1

这是一个相当古老的问题，但我仍然想澄清一下，接受的答案实际上是不正确的。通过执行以下代码，

PowerMockito.mockStatic(Collections.class);
Collections.shuffle(Mockito.anyListOf(Something.class));

之后所有的验证都会通过:

PowerMockito.verifyStatic(); // Verify shuffle was called exactly once
Collections.shuffle(Mockito.anyListOf(Something.class));

即使您不调用 test.doSomething();，答案中提供的测试仍然会通过。正确的测试方法是实际检查列表中的项目是否已正确排序。