我看到了一种非常奇怪的行为,试图截短类myMethod(param)
的方法MyClass
,该方法是在抽象父类MyAbstractBaseClass
中定义的。
当我尝试存根(使用doReturn("...").when(MyClassMock).myMethod(...)
等)时,这个方法失败了,在不同的场景下会抛出不同的异常。异常就在这一行抛出。
当我使用doReturn("...").when(MyClassMock).myMethod(CONCRETE PARAM CLASS OBJECT)
时,出现以下异常:
org.mockito.exceptions.misusing.WrongTypeOfReturnValue:
String cannot be returned by hasValidExpirationDate()
hasValidExpirationDate() should return boolean
at ...
hasValidExpirationDate()
不是被存根的方法,但它是由抽象基类中MyMethod(param)
的实际实现调用的。当我使用
doReturn("...").when(MyClassMock).myMethod(any(PARAMCLASS.class))
时,出现以下异常:org.mockito.exceptions.misusing.InvalidUseOfMatchersException:
Invalid use of argument matchers!
0 matchers expected, 1 recorded.
This exception may occur if matchers are combined with raw values:
等等。
但是当我在子类中定义方法
myMethod(param)
时,代码不再失败。我在MyClass
中的具体实现只是调用MyClass
并返回它,因此除了修复单元测试之外,它没有任何效果。所以看起来mockito只能在被模仿的类中定义stub方法,而不能在超级类中。我正在阅读mockito文档,我看不出它在哪里说继承的方法不能被存根。
super.myMethod(param)
既不是myMethod(param)
也不是static
。代码:
类别:
import java.io.Serializable;
public class BaseCard implements Serializable {
public boolean hasValidExpirationDate() {
return true;
}
}
类别:
abstract class Card extends BaseCard {
public Card () { }
public String getUnexpiredStringForNetwork(){
//If the date is invalid return empty string, except for Discover.
if( ! hasValidExpirationDate()){
return "hi";
}
return "hello";
}
}
类别:
public class DecryptedCard extends Card {
}
类别:
import static org.mockito.Mockito.doReturn;
import static org.mockito.Mockito.mock;
import org.junit.Test;
public class MyTest {
@Test
public void test() {
DecryptedCard decryptedCardMock = mock(DecryptedCard.class);
doReturn("ABC").when(decryptedCardMock).getUnexpiredStringForNetwork();
}
}
失败:
org.mockito.exceptions.misusing.WrongTypeOfReturnValue:
String cannot be returned by hasValidExpirationDate()
hasValidExpirationDate() should return boolean
***
If you're unsure why you're getting above error read on.
Due to the nature of the syntax above problem might occur because:
1. This exception *might* occur in wrongly written multi-threaded tests.
Please refer to Mockito FAQ on limitations of concurrency testing.
2. A spy is stubbed using when(spy.foo()).then() syntax. It is safer to stub spies -
- with doReturn|Throw() family of methods. More in javadocs for Mockito.spy() method.
at Card.getUnexpiredStringForNetwork(Card.java:10)
at DecryptedCard.getUnexpiredStringForNetwork(DecryptedCard.java:1)
at MyTest.test(MyTest.java:13)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:42)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:68)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:47)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)
at org.junit.runners.ParentRunner.run(ParentRunner.java:300)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
最佳答案
根据this SO answer,当父类是非公共的时,模拟行为不能得到保证,如issue 212中所述。
(感谢brice在另一个线程中给出了正确的答案,并感谢vladimir、jb niset和acdcjunior在comments线程中共享调试进度!)