Question

我有像这样的Java 8 Predicate。如何为此

编写单元测试

 Predicate<DTO> isDone = (dtO) ->
                (!dto.isFinished() &&
                !dto.isCompleted());

由于

Answer 1

如果您有对谓词的引用（如您的示例中所示），那么我看不出任何问题。以下是Mockito / JUnit的简单示例：

@Mock
private DTO mockDTO;

@Test
public void testIsDone_Finished_NotComplete()
{
    when(mockDTO.isFinished()).thenReturn(true);
    when(mockDTO.isCompleted()).thenReturn(false);

    boolean expected = false;
    boolean actual = isDone.test(mockDTO);

    Assert.assertEquals(expected, actual);
}

Answer 2

我会像那样测试：

private final Predicate<DTO> isDone = (dto) ->
        (!dto.isFinished() && !dto.isCompleted());

@Test
public void a() throws Exception {
    // given
    DTO dto = new DTO(true, true);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isFalse();
}

@Test
public void s() throws Exception {
    // given
    DTO dto = new DTO(true, false);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isFalse();
}

@Test
public void d() throws Exception {
    // given
    DTO dto = new DTO(false, true);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isFalse();
}

@Test
public void f() throws Exception {
    // given
    DTO dto = new DTO(false, false);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isTrue();
}

@AllArgsConstructor
public static class DTO {
    private final boolean isFinished;
    private final boolean isCompleted;

    public boolean isFinished() {
        return isFinished;
    }

    public boolean isCompleted() {
        return isCompleted;
    }
}

而不是a，s和f将测试命名为：should_be_done_when_it_is_both_finished_and_completed。

我认为DTO只是一个值对象，所以我宁愿创建真实实例而不是使用mock。

单元测试Java 8谓词

2 个答案: