From f9c25fc4acac6a5965d68584d68eee7539e4ba45 Mon Sep 17 00:00:00 2001
From: Jason Zaugg <jzaugg@gmail.com>
Date: Fri, 23 Nov 2012 17:35:52 +0100
Subject: Forbid await in try/catch.

---
 src/main/scala/scala/async/AsyncAnalysis.scala  | 10 +++++++++
 src/test/scala/scala/async/neg/NakedAwait.scala | 30 +++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/src/main/scala/scala/async/AsyncAnalysis.scala b/src/main/scala/scala/async/AsyncAnalysis.scala
index 35d2854..c160776 100644
--- a/src/main/scala/scala/async/AsyncAnalysis.scala
+++ b/src/main/scala/scala/async/AsyncAnalysis.scala
@@ -53,6 +53,16 @@ private[async] final case class AsyncAnalysis[C <: Context](override val c: C) e
       reportUnsupportedAwait(function, "nested function")
     }
 
+    override def traverse(tree: Tree) {
+      def containsAwait = tree exists isAwait
+      tree match {
+        case Try(_, _, _) if containsAwait =>
+          reportUnsupportedAwait(tree, "try/catch")
+        case _ =>
+          super.traverse(tree)
+      }
+    }
+
     /**
      * @return true, if the tree contained an unsupported await.
      */
diff --git a/src/test/scala/scala/async/neg/NakedAwait.scala b/src/test/scala/scala/async/neg/NakedAwait.scala
index 8b85977..a0c4e4d 100644
--- a/src/test/scala/scala/async/neg/NakedAwait.scala
+++ b/src/test/scala/scala/async/neg/NakedAwait.scala
@@ -87,4 +87,34 @@ class NakedAwait {
       """.stripMargin
     }
   }
+
+  @Test
+  def tryBody() {
+    expectError("await must not be used under a try/catch.") {
+      """
+        | import _root_.scala.async.AsyncId._
+        | async { try { await(false) } catch { case _ => } }
+      """.stripMargin
+    }
+  }
+
+  @Test
+  def catchBody() {
+    expectError("await must not be used under a try/catch.") {
+      """
+        | import _root_.scala.async.AsyncId._
+        | async { try { () } catch { case _ => await(false) } }
+      """.stripMargin
+    }
+  }
+
+  @Test
+  def finallyBody() {
+    expectError("await must not be used under a try/catch.") {
+      """
+        | import _root_.scala.async.AsyncId._
+        | async { try { () } finally { await(false) } }
+      """.stripMargin
+    }
+  }
 }
-- 
cgit v1.2.3