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如何撤消/重置PowerMockito。模拟静态?

powermockito powermock mocking static java

Kalle Richter · 技术社区 · 7 年前

假设我有以下课程

public class StaticClass {

    public static void staticMethod() throws SomeException {
        System.out.println("staticMethod");
    }

    private StaticClass() {
    }
}

和

public class SomeClass {

    public void someMethod() {
        try {
            StaticClass.staticMethod();
        }catch(SomeException ex) {
            System.out.println("SomeException occurred");
            return;
        }
        System.out.println("SomeException didn't occur");
    }
}

我正在用它进行测试

@RunWith(PowerMockRunner.class)
@PrepareForTest(StaticClass.class)
public class SomeClassTest {

    @Test
    public void testStaticMethod() throws Exception {
        mockStatic(StaticClass.class);
        doThrow(new SomeException("unimportant message")).when(StaticClass.class,
                "staticMethod");
        //test something where exception is needed
        SomeClass instance = new SomeClass();
        try {
            instance.someMethod();
            fail("IllegalStateException expected");
        }catch(IllegalStateException expected) {
        }
        //now test something where exception isn't needed
        instance.someMethod();
    }
}

如何撤消要抛出的静态模拟/配置 SomeException 这样我就可以在第二个 instance.someMethod() ?

PowerMock: How to unmock a method? 不适用,因为没有可传递到的模拟引用 Mockito.reset 和通过 StaticClass 原因 java.lang.ClassCastException: java.lang.Class cannot be cast to org.mockito.internal.creation.bytebuddy.MockAccess .

某些例外情况 简单扩展 Exception .

SSCCE位于 https://gitlab.com/krichter/powermock-undo-statik-mocking .

我正在使用PowerMock 1.7.3。

2 回复 | 直到 7 年前

Andrew S 7 年前

我的观点是,但一般来说,单元测试应该使用单个代码路径。(我认为这是将单一责任应用于测试方法。)

但是我关于拆分测试的建议确实解决了这个问题。我不知道细节,但@PrepareForTest提供了一个新的StaticClass 对于每个测试 .

这些单独的测试工作:

@Test
public void testStaticMethodWhenSomethingUnexpectedHappens() throws Exception {
    mockStatic(StaticClass.class);
    // changed exception type
    doThrow(new IllegalStateException("unimportant message")).when(StaticClass.class, "staticMethod");

    SomeClass instance = new SomeClass();
    try {
        instance.someMethod();
        fail("IllegalStateException expected");
    } catch (IllegalStateException expected) {
    }

    // added verification
    verifyStaticMethodWasInvokedOneTime();
}

@Test
public void testStaticMethodHappyPath() throws Exception {
    mockStatic(StaticClass.class);
    doNothing().when(StaticClass.class, "staticMethod");

    SomeClass instance = new SomeClass();
    instance.someMethod();

    // added verification
    verifyStaticMethodWasInvokedOneTime();
}

private void verifyStaticMethodWasInvokedOneTime() throws SomeException {
    verifyStatic(StaticClass.class);
    StaticClass.staticMethod();
}

Ryu S. 4 年前

对于任何想知道如何为那些讨厌的私有静态最终记录器重置PowerMocks e.x的人。。。

有一个 issue (参见Karl在accepted solution中的评论)解决了这个问题,解决方案是在方法级别使用@PrepareForTest。

因此,在测试方法中,您需要注释

/*
 * Test for MyClass.java which uses a private static final logger
 */
public class MyStaticMockTest {

  static final Logger logger = PowerMockito.mock(Logger.class);

  @BeforeClass
  public static void setup() {

    PowerMockito.mockStatic(LoggerFactory.class);
    PowerMockito.when(LoggerFactory.getLogger(MyClass.class))
        .thenReturn(MyStaticMockTest.logger);
  }


  @Test
  @PrepareForTest({LoggerFactory.class, Logger.class})
  public void testit() {
    MyClass mc = new MyClass();

    mc.methodWithSomeLogging();

    Mockito.verify(MyStaticMockTest.logger).info("some message");
  }

  @Test
  @PrepareForTest({LoggerFactory.class, Logger.class})
  public void testit() {
    MyClass mc = new MyClass();

    mc.anotherMethodWithSomeLoggingButUsingSameMessage();

    //Method will pass and not complain about info being called 2x
    Mockito.verify(MyStaticMockTest.logger, Mockito.times(1)).info("some message");
  }
}

如果要重置每个方法,只需在类上放置@PrepareForTest修饰符,而不是方法