Discovered via irc one more assertion in the ma...

Discovered via irc one more assertion in the matcher which was asserting
something too specific. Fixed, no review.

2 files changed, 4 insertions, 5 deletions

diff --git a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
index 73ecbdee70..00f4186805 100644
--- a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
+++ b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
@@ -566,11 +566,13 @@ trait ParallelMatching extends ast.TreeDSL
         def isEquivalent    = head.tpe =:= pattern.tpe
         def isObjectTest    = pattern.isObject && (head.tpe =:= pattern.tpe)
 
+        def whichSubs = if (head.isCaseClass) (pattern expandToArity head.arity) else Nil
+
         def ifElsePattern(yes: Pattern) = if (isEquivalent) yes else pattern
 
         def succDummy = succRows += ((j, NoPattern :: pmatch.dummies))
         def succTyped(pp: Pattern) = succRows += ((j, ifElsePattern(pp) :: pmatch.dummies))
-        def succSubs  = succRows += ((j, ifElsePattern(NoPattern) :: (pattern expandToArity head.arity)))
+        def succSubs  = succRows += ((j, ifElsePattern(NoPattern) :: whichSubs))
         def failOnly  = failRows += ((j, pattern))
 
         pattern match {
diff --git a/src/compiler/scala/tools/nsc/matching/Patterns.scala b/src/compiler/scala/tools/nsc/matching/Patterns.scala
index 55d35bf884..7621c1c2f3 100644
--- a/src/compiler/scala/tools/nsc/matching/Patterns.scala
+++ b/src/compiler/scala/tools/nsc/matching/Patterns.scala
@@ -139,10 +139,7 @@ trait Patterns extends ast.TreeDSL {
 
     private def isColonColon = cleanName == "::"
 
-    override def expandToArity(newArity: Int): List[Pattern] = {
-      assert(newArity == args.length)
-      toPats(args)
-    }
+    override def expandToArity(newArity: Int): List[Pattern] = toPats(args)
 
     override def simplify(pv: PatternVar) =
       if (args.isEmpty) this rebindToEmpty tree.tpe