Kotlin和JUnit5断言抛出异常：使用assertFailsWith分别声明和执行

Question

在使用JUnit5的Kotlin中，我们可以使用assertFailsWith

在JUnit5的Java中，可以使用assertThrows

@Test
@DisplayName("display() with wrong argument command should fail" )
void displayWithWrongArgument() {

    // Given a wrong argument
    String arg = "FAKE_ID"

    // When we call display() with the wrong argument
    Executable exec = () -> sut.display(arg);

    // Then it should throw an IllegalArgumentException
    assertThrows(IllegalArgumentException.class, exec);
}

@Test
fun `display() with wrong argument command should fail`() {

    // Given a wrong argument
    val arg = "FAKE_ID"

    // When we call display() with the wrong argument
    // ***executable declaration should go here ***

    // Then it should throw an IllegalArgumentException
    assertFailsWith<CrudException> { sut.display(arg) }
}

但是，我们如何用assertfailswith将声明和Kotlin中的执行分开呢？

Answer 1

只需像在Java中那样声明一个变量：

@Test
fun `display() with wrong argument command should fail`() {

    // Given a wrong argument
    val arg = "FAKE_ID"

    // When we call display() with the wrong argument
    val block: () -> Unit = { sut.display(arg) }

    // Then it should throw an IllegalArgumentException
    assertFailsWith<CrudException>(block = block)
}