Merge pull request #1256 from felixmulder/topic/test-bcode

Add bytecode checking infrastructure

3 files changed, 8 insertions, 4 deletions

diff --git a/src/dotty/tools/dotc/core/Definitions.scala b/src/dotty/tools/dotc/core/Definitions.scala
index bcc986755..5cb373cfd 100644
--- a/src/dotty/tools/dotc/core/Definitions.scala
+++ b/src/dotty/tools/dotc/core/Definitions.scala
@@ -486,6 +486,8 @@ class Definitions {
   def TASTYLongSignatureAnnot(implicit ctx: Context) = TASTYLongSignatureAnnotType.symbol.asClass
   lazy val TailrecAnnotType = ctx.requiredClassRef("scala.annotation.tailrec")
   def TailrecAnnot(implicit ctx: Context) = TailrecAnnotType.symbol.asClass
+  lazy val SwitchAnnotType = ctx.requiredClassRef("scala.annotation.switch")
+  def SwitchAnnot(implicit ctx: Context) = SwitchAnnotType.symbol.asClass
   lazy val ThrowsAnnotType = ctx.requiredClassRef("scala.throws")
   def ThrowsAnnot(implicit ctx: Context) = ThrowsAnnotType.symbol.asClass
   lazy val TransientAnnotType                = ctx.requiredClassRef("scala.transient")
diff --git a/src/dotty/tools/dotc/core/Types.scala b/src/dotty/tools/dotc/core/Types.scala
index 71ea6d2b3..cec6fd3b1 100644
--- a/src/dotty/tools/dotc/core/Types.scala
+++ b/src/dotty/tools/dotc/core/Types.scala
@@ -107,7 +107,7 @@ object Types {
      *        It makes no sense for it to be an alias type because isRef would always
      *        return false in that case.
      */
-    def isRef(sym: Symbol)(implicit ctx: Context): Boolean = stripTypeVar match {
+    def isRef(sym: Symbol)(implicit ctx: Context): Boolean = stripAnnots.stripTypeVar match {
       case this1: TypeRef =>
         this1.info match { // see comment in Namer#typeDefSig
           case TypeAlias(tp) => tp.isRef(sym)
diff --git a/src/dotty/tools/dotc/transform/PatternMatcher.scala b/src/dotty/tools/dotc/transform/PatternMatcher.scala
index 64b85a51f..24d0e9ae0 100644
--- a/src/dotty/tools/dotc/transform/PatternMatcher.scala
+++ b/src/dotty/tools/dotc/transform/PatternMatcher.scala
@@ -306,12 +306,11 @@ class PatternMatcher extends MiniPhaseTransform with DenotTransformer {thisTrans
     def emitSwitch(scrut: Tree, scrutSym: Symbol, cases: List[List[TreeMaker]], pt: Type, matchFailGenOverride: Option[Symbol => Tree], unchecked: Boolean): Option[Tree] = {
       // TODO Deal with guards?
 
-      def isSwitchableType(tpe: Type): Boolean = {
+      def isSwitchableType(tpe: Type): Boolean =
         (tpe isRef defn.IntClass) ||
         (tpe isRef defn.ByteClass) ||
         (tpe isRef defn.ShortClass) ||
         (tpe isRef defn.CharClass)
-      }
 
       object IntEqualityTestTreeMaker {
         def unapply(treeMaker: EqualityTestTreeMaker): Option[Int] = treeMaker match {
@@ -423,7 +422,8 @@ class PatternMatcher extends MiniPhaseTransform with DenotTransformer {thisTrans
         Match(intScrut, newCases :+ defaultCase)
       }
 
-      if (isSwitchableType(scrut.tpe.widenDealias) && cases.forall(isSwitchCase)) {
+      val dealiased = scrut.tpe.widenDealias
+      if (isSwitchableType(dealiased) && cases.forall(isSwitchCase)) {
         val valuesToCases = cases.map(extractSwitchCase)
         val values = valuesToCases.map(_._1)
         if (values.tails.exists { tail => tail.nonEmpty && tail.tail.exists(doOverlap(_, tail.head)) }) {
@@ -433,6 +433,8 @@ class PatternMatcher extends MiniPhaseTransform with DenotTransformer {thisTrans
           Some(makeSwitch(valuesToCases))
         }
       } else {
+        if (dealiased hasAnnotation defn.SwitchAnnot)
+          ctx.warning("failed to emit switch for `@switch` annotated match")
         None
       }
     }