Merge pull request scala#4095 from retronym/ticket/8933

lrytz · lrytz · commit 22bc1f89c13e · 2014-11-10T11:02:09.000+01:00
Fix problems in Symbol Literal static caching
diff --git a/src/compiler/scala/tools/nsc/transform/CleanUp.scala b/src/compiler/scala/tools/nsc/transform/CleanUp.scala
@@ -520,7 +520,9 @@ abstract class CleanUp extends Statics with Transform with ast.TreeDSL {
       * And, finally, be advised - Scala's Symbol literal (scala.Symbol) and the Symbol class of the compiler
       * have little in common.
       */
-      case Apply(fn, (arg @ Literal(Constant(symname: String))) :: Nil) if fn.symbol == Symbol_apply =>
+      case Apply(fn @ Select(qual, _), (arg @ Literal(Constant(symname: String))) :: Nil)
+        if treeInfo.isQualifierSafeToElide(qual) && fn.symbol == Symbol_apply && !currentClass.isTrait =>
+
         def transformApply = {
           // add the symbol name to a map if it's not there already
           val rhs = gen.mkMethodCall(Symbol_apply, arg :: Nil)
diff --git a/test/files/run/t8933.check b/test/files/run/t8933.check
@@ -0,0 +1 @@
+'traitSymbol
diff --git a/test/files/run/t8933/A_1.scala b/test/files/run/t8933/A_1.scala
@@ -0,0 +1,6 @@
+class MotherClass
+
+trait MixinWithSymbol {
+  self: MotherClass =>
+  def symbolFromTrait: Symbol = 'traitSymbol
+}
diff --git a/test/files/run/t8933/Test_2.scala b/test/files/run/t8933/Test_2.scala
@@ -0,0 +1,10 @@
+class MotherClass extends MixinWithSymbol {
+  val classSymbol = 'classSymbol
+}
+
+object Test {
+  def main(args: Array[String]) {
+    val symbol = (new MotherClass).symbolFromTrait
+    println(symbol)
+  }
+}
diff --git a/test/files/run/t8933b/A.scala b/test/files/run/t8933b/A.scala
@@ -0,0 +1,4 @@
+trait MixinWithSymbol {
+  self: MotherClass =>
+  def symbolFromTrait: Any = 'traitSymbol
+}
diff --git a/test/files/run/t8933b/Test.scala b/test/files/run/t8933b/Test.scala
@@ -0,0 +1,9 @@
+class MotherClass extends MixinWithSymbol {
+  def foo = 'sym1
+}
+
+object Test {
+  def main(args: Array[String]) {
+    (new MotherClass).symbolFromTrait
+  }
+}
diff --git a/test/files/run/t8933c.scala b/test/files/run/t8933c.scala
@@ -0,0 +1,14 @@
+object Test {
+  def main(args: Array[String]): Unit = {
+    try {    
+      {throw T; Symbol}.apply("a")
+      assert(false, "exception not thrown")
+    } catch {
+      case T => // ok
+      case t: Throwable =>
+        assert(false, "wrong not thrown: " + t)
+    }
+  }
+}
+
+object T extends Throwable
