Prohibit await in if condition (for now)

Test nested loops.

Control ANF tracing with another system property.

3 files changed, 14 insertions, 6 deletions

diff --git a/src/main/scala/scala/async/AnfTransform.scala b/src/main/scala/scala/async/AnfTransform.scala
index 0756baf..cf6ed04 100644
--- a/src/main/scala/scala/async/AnfTransform.scala
+++ b/src/main/scala/scala/async/AnfTransform.scala
@@ -77,9 +77,9 @@ private[async] final case class AnfTransform[C <: Context](override val c: C) ex
     def apply[T](prefix: String, args: Any)(t: => T): T = {
       indent += 1
       try {
-        //println(s"${indentString}$prefix($args)")
+        AsyncUtils.trace(s"${indentString}$prefix($args)")
         val result = t
-        //println(s"${indentString}= $result")
+        AsyncUtils.trace(s"${indentString}= $result")
         result
       } finally {
         indent -= 1
diff --git a/src/main/scala/scala/async/AsyncAnalysis.scala b/src/main/scala/scala/async/AsyncAnalysis.scala
index e319fe8..c1ee7f4 100644
--- a/src/main/scala/scala/async/AsyncAnalysis.scala
+++ b/src/main/scala/scala/async/AsyncAnalysis.scala
@@ -62,6 +62,10 @@ private[async] final case class AsyncAnalysis[C <: Context](override val c: C) e
       tree match {
         case Try(_, _, _) if containsAwait =>
           reportUnsupportedAwait(tree, "try/catch")
+          super.traverse(tree)
+        case If(cond, _, _) if containsAwait =>
+          reportUnsupportedAwait(cond, "condition")
+          super.traverse(tree)
         case Return(_) =>
           c.abort(tree.pos, "return is illegal within a async block")
         case _ =>
diff --git a/src/main/scala/scala/async/AsyncUtils.scala b/src/main/scala/scala/async/AsyncUtils.scala
index b2f6747..525f187 100644
--- a/src/main/scala/scala/async/AsyncUtils.scala
+++ b/src/main/scala/scala/async/AsyncUtils.scala
@@ -8,8 +8,12 @@ package scala.async
  */
 object AsyncUtils {
 
-  private val verbose = false || sys.props.getOrElse("scala.async.debug", "false").equalsIgnoreCase("true")
-  
-  private[async] def vprintln(s: => Any): Unit = if (verbose)
-    println("[async] "+s)
+  private def enabled(level: String) = sys.props.getOrElse(s"scala.async.$level", "false").equalsIgnoreCase("true")
+
+  private val verbose = enabled("debug")
+  private val trace   = enabled("trace")
+
+  private[async] def vprintln(s: => Any): Unit = if (verbose) println(s"[async] $s")
+
+  private[async] def trace(s: => Any): Unit = if (trace) println(s"[async] $s")
 }