How to check which exception is contained in a Failure[T]?

scala, scalatest

Solution

I'd go with something that doesn't really throw the exception, given that a `Failure` result is just another result that can be matched:

"Subject" should "throw proper exceptions.." in {
  val tryValue = // some method call...
  tryValue shouldBe a[Failure[_]]
  tryValue.failed.get shouldBe an[IllegalArgumentException]
}

The above separates the assertions: you'll see different test failures for the case where no failure happened and the case where the wrong failure happened.

Problem

I'm wondering about the best way to check the content of a failed `Try` using ScalaTest. What I'm doing at the moment looks like this: ``` "Subject" should "throw proper exceptions.." in { a[IllegalArgumentException] should be thrownBy { val tryValue = // some method call.. if (tryValue.isFailure) throw tryValue.failed.get } } ``` As you can see, I just unwrap the exception and throw it manually. Is there a more idiomatic way to achieve the same thing?

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