Question

使用JUnit4，您可以例如只需写：

@Test (expectedException = new UnsupportedOperationException()){...}

在JUnit5中怎么可能？我尝试过这种方式，但不确定是否相等。

@Test
    public void testExpectedException() {
        Assertions.assertThrows(UnsupportedOperationException.class, () -> {
            Integer.parseInt("One");});

Answer 1

是的，这些是等效的。

public class DontCallAddClass {
    public void add() {
        throws UnsupportedOperationException("You are not supposed to call me!");
    }
}

public class DontCallAddClassTest {

    private DontCallAddClass dontCallAdd = new DontCallAddClass();

    @Rule
    public ExpectedException exception = ExpectedException.none();

    @Test
    public void add_throwsException() {
       exception.expect(UnsupportedOperationException.class);
       dontCallAdd.add();
    }

    @Test(expected = UnsupportedOperationException.class)
    public void add_throwsException_differentWay() {
        dontCallAdd.add();
    }

    @Test
    public void add_throwsException() {
        Assertions.assertThrows(UnsupportedOperationException.class, dontCallAdd.add());
    }
}

以上三种测试方法是等效的。在Junit 5中使用最后一个。这是较新的方法。它还允许您利用Java 8 lambda。您还可以检查错误消息应该是什么。见下文：

public class DontCallAddClass {
    public void add() {
        throws UnsupportedOperationException("You are not supposed to call me!");
    }
}

public class DontCallAddClassTest {

    private DontCallAddClass dontCallAdd = new DontCallAddClass();

    @Rule
    public ExpectedException exception = ExpectedException.none();

    @Test
    public void add_throwsException() {
       exception.expect(UnsupportedOperationException.class);
       exception.expectMessage("You are not supposed to call me!");
       dontCallAdd.add();
    }

    // this one doesn't check for error message :(
    @Test(expected = UnsupportedOperationException.class)
    public void add_throwsException_differentWay() {
        dontCallAdd.add();
    }

    @Test
    public void add_throwsException() {
        Assertions.assertThrows(UnsupportedOperationException.class, dontCallAdd.add(), "You are not supposed to call me!");
    }
}

在此处查看更多信息：JUnit 5: How to assert an exception is thrown?

希望这可以清除

如何确保JUnit5中抛出特定异常？

1 个答案: