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/*
* Copyright (C) 2012 Typesafe Inc. <http://www.typesafe.com>
*/
package scala.async
import org.junit.runner.RunWith
import org.junit.runners.JUnit4
import org.junit.Test
import AsyncId._
import tools.reflect.ToolBox
@RunWith(classOf[JUnit4])
class TreeInterrogation {
@Test
def `a minimal set of vals are lifted to vars`() {
val cm = reflect.runtime.currentMirror
val tb = mkToolbox("-cp target/scala-2.10/classes")
val tree = tb.parse(
"""| import _root_.scala.async.AsyncId._
| async {
| val x = await(1)
| val y = x * 2
| def foo(a: Int) = { def nested = 0; a } // don't lift `nested`.
| val z = await(x * 3)
| foo(z)
| z
| }""".stripMargin)
val tree1 = tb.typeCheck(tree)
//println(cm.universe.show(tree1))
import tb.u._
val functions = tree1.collect {
case f: Function => f
case t: Template => t
}
functions.size mustBe 1
val varDefs = tree1.collect {
case ValDef(mods, name, _, _) if mods.hasFlag(Flag.MUTABLE) => name
}
varDefs.map(_.decoded.trim).toSet mustBe (Set("state$async", "await$1", "await$2"))
varDefs.map(_.decoded.trim).toSet mustBe (Set("state$async", "await$1", "await$2"))
val defDefs = tree1.collect {
case t: Template =>
val stats: List[Tree] = t.body
stats.collect {
case dd : DefDef
if !dd.symbol.isImplementationArtifact
&& !dd.symbol.asTerm.isAccessor && !dd.symbol.asTerm.isSetter => dd.name
}
}.flatten
defDefs.map(_.decoded.trim).toSet mustBe (Set("foo$1", "apply", "resume$async", "<init>"))
}
}
object TreeInterrogation extends App {
def withDebug[T](t: => T) {
def set(level: String, value: Boolean) = System.setProperty(s"scala.async.$level", value.toString)
val levels = Seq("trace", "debug")
def setAll(value: Boolean) = levels.foreach(set(_, value))
setAll(true)
try t finally setAll(false)
}
withDebug {
val cm = reflect.runtime.currentMirror
val tb = mkToolbox("-cp target/scala-2.10/classes -Xprint:all")
val tree = tb.parse(
"""
| import scala.async.Async.{async, await}
| import scala.concurrent.{future, ExecutionContext, Await}
| import ExecutionContext.Implicits._
| import scala.concurrent.duration._
|
| try {
| val f = async { throw new Exception("problem") }
| Await.result(f, 1.second)
| } catch {
| case ex: Exception if ex.getMessage == "problem" => // okay
| }
| ()
| """.stripMargin)
println(tree)
val tree1 = tb.typeCheck(tree.duplicate)
println(cm.universe.show(tree1))
println(tb.eval(tree))
}
}
|
