java - Mockito doThrow on void method with null argument not throw exception : What am I doing wrong?

Question

我不确定我是发现了错误还是只是做错了。我试图在调用方法时模拟抛出异常(通常相对容易)，除了方法是 void 返回类型，以及要传入的对象(为什么抛出错误) 为 null。这样可以通过isNull()类型进行编译，但是还是不报错。

package some.example;

import static org.mockito.Matchers.isNull;
import static org.mockito.Mockito.doThrow;
import static org.mockito.Mockito.reset;
import static org.mockito.Mockito.verify;
import static org.mockito.MockitoAnnotations.initMocks;

import javax.jms.Message;
import javax.jms.MessageListener;

import org.mockito.Mock;
import org.springframework.jms.listener.AbstractMessageListenerContainer;
import org.springframework.jms.listener.SessionAwareMessageListener;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;

public class TestClass {
    @Mock
    private AbstractMessageListenerContainer messageContainer;

    @BeforeClass
    public void setUpMocks() {
        initMocks(this);

        doThrow(new IllegalArgumentException()).when(messageContainer).setupMessageListener(
                isNull(MessageListener.class));
        doThrow(new IllegalArgumentException()).when(messageContainer).setupMessageListener(
                isNull(SessionAwareMessageListener.class));
    }

    @AfterMethod
    public void resetMocks() {
        reset(messageContainer);
    }

    @Test(expectedExceptions = { IllegalArgumentException.class })
    public void testSetUpQueueConsumerWithNullMessageListener() throws Exception {
        final MessageListener messageListener = null;
        try (final QueueConsumer consumer = new QueueConsumer(messageContainer, messageListener)) {
        } finally {
            verify(messageContainer).setupMessageListener(messageListener);
        }
    }

    @Test(expectedExceptions = { IllegalArgumentException.class })
    public void testSetUpQueueConsumerWithNullSessionAwareMessageListener() throws Exception {
        final SessionAwareMessageListener<Message> messageListener = null;
        try (final QueueConsumer consumer = new QueueConsumer(messageContainer, messageListener)) {
        } finally {
            verify(messageContainer).setupMessageListener(messageListener);
        }
    }

    public class QueueConsumer implements AutoCloseable {
        private final AbstractMessageListenerContainer messageContainer;

        QueueConsumer(final AbstractMessageListenerContainer messageContainer,
                final SessionAwareMessageListener<? extends Message> messageListener) {
            this(messageContainer);
            this.messageContainer.setupMessageListener(messageListener);
        }

        QueueConsumer(final AbstractMessageListenerContainer messageContainer, final MessageListener messageListener) {
            this(messageContainer);
            this.messageContainer.setupMessageListener(messageListener);
        }

        private QueueConsumer(final AbstractMessageListenerContainer messageContainer) {
            if (messageContainer == null) {
                throw new IllegalArgumentException("MessageListenerContainer cannot be null");
            }
            this.messageContainer = messageContainer;
        }

        public void stop() {
            messageContainer.stop();
        }

        @Override
        public void close() throws Exception {
            stop();
        }
    }
}

相关maven依赖:

<dependency>
    <groupId>org.testng</groupId>
    <artifactId>testng</artifactId>
    <version>6.8.21</version>
    <scope>test</scope>
</dependency>
<dependency>
    <groupId>org.mockito</groupId>
    <artifactId>mockito-core</artifactId>
    <version>2.0.8-beta</version>
    <scope>test</scope>
</dependency>
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jms</artifactId>
    <version>${org.springframework.version}</version>
</dependency>

编辑

我添加了精简的真实代码。今天早上我更多地研究了代码，发现我错误地使用了 Mockito 的 reset()。我认为它会将模拟重置为其未验证状态，但它也会删除 doThrow() stub 。我不得不按如下方式更改初始化方法:

@BeforeClass
public void setUpMocks() {
    initMocks(this);
}

@BeforeMethod
public void setUpThrows() {
    doThrow(new IllegalArgumentException()).when(messageContainer).setupMessageListener(
            isNull(MessageListener.class));
    doThrow(new IllegalArgumentException()).when(messageContainer).setupMessageListener(
            isNull(SessionAwareMessageListener.class));
}

Answer 1

如评论和编辑中所解决:请注意 reset方法完全重置模拟，包括 stub 和交互(后者用于验证)。

作为warned in the Mockito documentation , reset 在你的测试中通常是一个不好的迹象:如果它出现在测试方法的中间，通常该方法应该被分成多个较小的测试，如果它出现在 @After 或 @AfterMethod 这意味着您的测试设置在测试之间存在污染。将您的模拟保存在实例字段中，而不是静态字段中，在 @Before (JUnit) 或 @BeforeMethod (TestNG) 方法中初始化，以确保它们在每个之前被完全覆盖在测试类中测试。