如何模拟从抽象类继承的受保护子类方法？

Question

如何使用Mockito或PowerMock来模拟由子类实现但从抽象超类继承的受保护方法？

换句话说,我想在模拟"doSomethingElse"时测试"doSomething"方法.

抽象超级

public abstract class TypeA {

    public void doSomething() {     

        // Calls for subclass behavior
        doSomethingElse();      
    }

    protected abstract String doSomethingElse();

}

子类实现

public class TypeB extends TypeA {

    @Override
    protected String doSomethingElse() {
        return "this method needs to be mocked";
    }

}

解

这里给出的答案是正确的,如果涉及的类在同一个包中,它们将起作用.

但是如果涉及不同的包,则可以选择用户PowerMock.以下示例适用于我.当然可能有其他方法可以做到这一点,这是有效的.

import static org.junit.Assert.assertEquals;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest({ TypeB.class })
public class TestAbstract {

    @Test
    public void test_UsingPowerMock() throws Exception {
        // Spy a subclass using PowerMock
        TypeB b = PowerMockito.spy(new TypeB());
        String expected = "some value for mock";

        // Mock a method by its name using PowerMock again
        PowerMockito.doReturn(expected).when(b, "doSomethingElse");

        // Calls the 
        String actual = b.doSomething();
        assertEquals(expected, actual);     

    }
}

注意:使用Java 5,jUnit 4.11,Mockito 1.9.0和PowerMock 1.4.12进行测试.

Answer 1

您可以Mockito.CALLS_REAL_METHODS在模拟抽象方法时使用.这将调用类的原始方法,您可以自己模拟所有抽象方法.

TypeA typeA = mock(TypeA.class, Mockito.CALLS_REAL_METHODS);
when(typeA.doSomethingElse()).thenReturn("Hello");
typeA.doSomething();

或者您使用间谍直接在TypeB上进行测试:

TypeB typeB = spy(new TypeB());
when(typeB.doSomethingElse()).thenReturn("Hello");
typeB.doSomething();