java - Mockito:验证模拟(带有 "RETURNS_DEEP_STUBS")返回比预期更多的调用

Question

查看下面的代码，我只希望对 getSand() 的调用发生一次，但测试失败了四次。这些电话在哪里发生？我想编写一个测试以确保只对 getSand() 进行一次调用。

来源

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Answers;
import org.mockito.Mock;
import org.mockito.runners.MockitoJUnitRunner;

import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

@RunWith(MockitoJUnitRunner.class)
public class DeepSandTest {

    @Mock(answer = Answers.RETURNS_DEEP_STUBS)
    SandBox mockSandBox;

    @Test
    public void should(){
        when(mockSandBox.getSand().doA()).thenReturn(1);
        when(mockSandBox.getSand().doB()).thenReturn(1);
        when(mockSandBox.getSand().doC()).thenReturn(1);

        DeepSand deepSand = new DeepSand(mockSandBox);
        deepSand.getTipple();

        verify(mockSandBox, times(1)).getSand();
    }

    public class DeepSand{

        private SandBox sandBox;

        public DeepSand(SandBox sandBox) {
            this.sandBox = sandBox;
        }

        public void getTipple(){
            Sand sand = sandBox.getSand();
            sand.doA();
            sand.doB();
            sand.doC();
        }
    }

    public interface SandBox{
        public Sand getSand();
    }

    public interface Sand{
        public Integer doA();
        public Integer doB();
        public Integer doC();
    }
}

输出

org.mockito.exceptions.verification.TooManyActualInvocations: 
mockSandBox.getSand();
Wanted 1 time:
-> at DeepSandTest.should(DeepSandTest.java:26)
But was 4 times. Undesired invocation:
-> at DeepSandTest.should(DeepSandTest.java:20)

详细信息Java 1.6、JUnit 4.11、Mockito 1.9.5

经验教训

如果您将深度 stub 视为一棵模拟对象树，那么您应该只验证叶子(“链中的最后一个模拟”)，因为节点包含在设置叶子行为所需的调用链中。换句话说，节点在叶子的设置过程中被调用。

Answer 1

因为 deeps stub 是 not supported in the verification API，所以它将您的设置计为调用，并在第二次通话时提示:

when(mockSandBox.getSand().doB()).thenReturn(1);

我会跳过使用 RETURNS_DEEP_STUBS 而只使用另一个模拟:

...
@Mock
SandBox mockSandBox;

@Mock
Sand sand;

@Test
public void should(){
    when(mockSandBox.getSand()).thenReturn(sand);
    when(sand.doA()).thenReturn(1);
    when(sand.doB()).thenReturn(1);
    when(sand.doC()).thenReturn(1);
...