Question

刚开始使用Scala进行单元测试，我对Scala中如何处理异常感到困惑。以下是JUnit测试的示例。

class Test {
  @Test
  void someTest {
    try {
      //Something
    } catch(Exception e) {
      Assert.assertTrue(e.getCause() instanceOf IOException);
    }
  }
}

现在我想在Scala中做同样的事情，我试过

class Test {
  @Test def someTest {
    try {
      //Something
    } catch {
      case e: Exception => assertTrue(e.getCause().isInstanceOf[IOException])
    }
  }
}

但我的IDE一直在抱怨Method Apply is not a member of type Any。我阅读了Scala中的异常处理，发现你应该使用模式匹配器，并且no exception handling in Scala。这究竟是如何工作的？

Answer 1

如果您正在测试scala代码，我建议使用比ScalaTest等jUnit更精简的东西。

import java.io.IOException

import org.scalatest._
import org.scalatest.FlatSpec
import org.scalatest.matchers.ShouldMatchers

object SomeCode
{
    def apply() = {
        throw new IOException
    }
}

class SomeTest
  extends FlatSpec
  with ShouldMatchers
{
    "Something" should "throw an IOException, TODO: why ?" in
    {
        intercept[IOException] {
            SomeCode()
        }
    }

    it should "also throw an IOException here" in
    {
        evaluating { SomeCode() } should produce [IOException]
    }
}

nocolor.run( new SomeTest )

Scala相当于instanceOf Java和异常处理

1 个答案: