Testing an assertion that something must not compile

Question

The problem

When I\'m working with libraries that support type-level programming, I often find myself writing comments like the following (from an example presente

Answer 1

Based on the links provided by Miles Sabin I was able to use the akka version

import scala.tools.reflect.ToolBox

object TestUtils {

  def eval(code: String, compileOptions: String = "-cp target/classes"): Any = {
    val tb = mkToolbox(compileOptions)
    tb.eval(tb.parse(code))
  }

  def mkToolbox(compileOptions: String = ""): ToolBox[_ <: scala.reflect.api.Universe] = {
    val m = scala.reflect.runtime.currentMirror
    m.mkToolBox(options = compileOptions)
  }
}

Then in my tests I used it like this

def result = TestUtils.eval(
  """|import ee.ui.events.Event
     |import ee.ui.events.ReadOnlyEvent
     |     
     |val myObj = new {
     |  private val writableEvent = Event[Int]
     |  val event:ReadOnlyEvent[Int] = writableEvent
     |}
     |
     |// will not compile:
     |myObj.event.fire
     |""".stripMargin)

result must throwA[ToolBoxError].like {
  case e => 
    e.getMessage must contain("value fire is not a member of ee.ui.events.ReadOnlyEvent[Int]") 
}