PowerMock的expectNew()并没有按预期模拟构造函数

Question

我正在尝试学习各种模拟库的细节,PowerMock(特别是EasyMock扩展)是下一个列表.我试图模拟一个构造函数,当我尝试复制它们时,提供的示例没有相同的响应.据我所知,它从不嘲笑构造函数,只是继续进行,就像它是正常的一样.

这是测试类:

@RunWith(PowerMockRunner.class)
@PrepareForTest({Writer.class})
public class FaultInjectionSituationTest {

    @Test
    public void testActionFail() throws Exception {
        FaultInjectionSituation fis = new FaultInjectionSituation();
        PowerMock.expectNew(Writer.class, "test")
           .andThrow(new IOException("thrown from mock"));
        PowerMock.replay(Writer.class);
        System.out.println(fis.action());
        PowerMock.verify(Writer.class);
    }

}

我尝试用EasyMock.isA(String.class)替换"test",但它产生了相同的结果.

这是FaultInjectionSituation:

public class FaultInjectionSituation {

    public String action(){
        Writer w;
        try {
            w = new Writer("test");
        } catch (IOException e) {
            System.out.println("thrown: " + e.getMessage());
            return e.getLocalizedMessage();
        }
        return "returned without throw";
    }
}

"作家"只不过是一个类的外壳:

public class Writer {
    public Writer(String s) throws IOException {
    }

    public Writer() throws IOException{
    }
}

当测试运行时,它打印出"return without return",表示从未抛出异常.

Answer 1

您还需要准备调用构造函数的类,因此PowerMock知道期望一个模拟的构造函数调用.尝试使用以下代码更新代码:

@RunWith(PowerMockRunner.class)
@PrepareForTest({Writer.class, FaultInjectionSituation.class})
public class FaultInjectionSituationTest { 
 // as before
}