Question

我正在努力学习JUnit。处理特定问题我决定使用JUnitParams参数提供程序。测试方法I写入的每组参数应包含两个输入值和一个列表，对于该列表将测试方法调用的结果：

private static final Object[] getConstraints() {
    return new Object[]{
            new Object[]{15, Equipment.WHITEBOARD, Arrays.asList(new Classroom[]{classroomA, classroomB})},
            new Object[]{15, Equipment.PROJECTOR, Arrays.asList(new Classroom[]{classroomB})},
            new Object[]{15, Equipment.MICROPHONE, Arrays.asList(new Classroom[]{classroomA})},
            new Object[]{30, Equipment.WHITEBOARD, Arrays.asList(new Classroom[]{classroomB})},
            new Object[]{30, Equipment.PROJECTOR, Arrays.asList(new Classroom[]{classroomB})},
            new Object[]{30, Equipment.MICROPHONE, Arrays.asList(new Classroom[]{})},
            new Object[]{45, Equipment.WHITEBOARD, Arrays.asList(new Classroom[]{})},
            new Object[]{45, Equipment.PROJECTOR, Arrays.asList(new Classroom[]{})},
            new Object[]{45, Equipment.MICROPHONE, Arrays.asList(new Classroom[]{})},
    };
}

classroomA和classroomB实际上是在每次测试执行之前准备好的Mockito存根：

@Before
public void setUp() {
    classroomA = mock(Classroom.class);
    classroomB = mock(Classroom.class);
    classrooms = Arrays.asList(new Classroom[]{classroomA, classroomB});

    when(classroomA.getName()).thenReturn("A");
    when(classroomA.getCapacity()).thenReturn(20);
    when(classroomA.getEquipment()).thenReturn(Arrays.asList(new Equipment[]{Equipment.WHITEBOARD, Equipment.MICROPHONE}));

    when(classroomB.getName()).thenReturn("B");
    when(classroomB.getCapacity()).thenReturn(40);
    when(classroomB.getEquipment()).thenReturn(Arrays.asList(new Equipment[]{Equipment.WHITEBOARD, Equipment.PROJECTOR}));

    bookingSystem = new BookingSystem(classrooms);
}

当我尝试使用上述Classroom个对象列表时出现问题：

@Test
@Parameters(method = "getConstraints")
public void shouldBookClassroomMeetingConstraints(int capacity, Equipment equipment, List<Classroom>
        suitableClassrooms) {
    Assert.assertTrue("Should book a classroom that has a minimum capacity of " + capacity + " and has " +
            equipment,
            suitableClassrooms.contains(bookingSystem.book(capacity, equipment, ANY_DAY_OF_WEEK, ANY_HOUR)));
}

调试显示在第一次运行期间suitableClassrooms包含2个对象，但进一步检查显示所有元素都为空 - 我准备的存根不存在。显然，测试不会通过或失败，应该通过或失败。

将MUnitParams与Mockito一起使用是否存在限制，或者我使用它们是错误的吗？使用它们的正确方法是什么？

这也可能是一种错误的单元测试技术。如果是这种情况，编写测试的正确方法是什么，以验证方法调用的结果是否在给定数组中？

Answer 1

您测试不起作用，因为JUnitParamsRunner跑步者在调用getConstraints方法之前甚至在@Before之前收集测试参数（即调用@BeforeClass方法）。因此，classroomA和classroomB在此时为空。这就是suitableClassrooms由null元素组成的原因。
解决方案是在classroomA方法中初始化classroomB和getConstraints()。

我相信你可以在这里摆脱mockito。 Classroom看起来像POJO，并且没有必要模拟POJO。在这种情况下，您只需创建Classroom实例并填写必要的数据。

Answer 2

您需要让课程知道您正在使用Mockito运行测试用例。在课程级别添加以下内容，它应该可以正常工作。

@RunWith(MockitoJUnitRunner.class)

如何在JUnitParams参数提供程序中使用Mockito存根？

2 个答案: