Fix for #3136 by reverting the line in r18184 w...

Fix for #3136 by reverting the line in r18184 which caused this and
other regressions. The downside is that the #1697 test case no longer
passes, but protracted shrug because it wasn't entirely fixed anyway.
Review by moors. (Can you triangulate your way to a patch where both
work simultaneously? It's today's bonus challenge!)

3 files changed, 27 insertions, 5 deletions

diff --git a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
index 4a000b1901..ab7b9adf72 100644
--- a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
+++ b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
@@ -537,7 +537,10 @@ trait ParallelMatching extends ast.TreeDSL
             case Pattern(LIT(null), _) if !(p =:= s)        => (None, passr)      // (1)
             case x if isObjectTest                          => (passl(), None)    // (2)
             case Pattern(Typed(pp, _), _)     if sMatchesP  => (typed(pp), None)  // (4)
-            case Pattern(_: UnApply, _)                     => (passl(), passr)
+            // The next line used to be this which "fixed" 1697 but introduced
+            // numerous regressions including #3136.
+            // case Pattern(_: UnApply, _)                     => (passl(), passr)
+            case Pattern(_: UnApply, _)                     => (None, passr)
             case x if !x.isDefault && sMatchesP             => (subs(), None)
             case x if  x.isDefault || pMatchesS             => (passl(), passr)
             case _                                          => (None, passr)
@@ -692,8 +695,8 @@ trait ParallelMatching extends ast.TreeDSL
       }
 
       def createLabelBody(index: Int, pvgroup: PatternVarGroup) = {
-        def args = pvgroup.syms
-        def vdefs = pvgroup.valDefs
+        val args = pvgroup.syms
+        val vdefs = pvgroup.valDefs
 
         val name = "body%" + index
         require(_labelSym == null)
@@ -712,8 +715,8 @@ trait ParallelMatching extends ast.TreeDSL
       }
 
       def getLabelBody(pvgroup: PatternVarGroup): Tree = {
-        def idents = pvgroup map (_.rhs)
-        def vdefs = pvgroup.valDefs
+        val idents = pvgroup map (_.rhs)
+        val vdefs = pvgroup.valDefs
         referenceCount += 1
         // if (idents.size != labelParamTypes.size)
         //   consistencyFailure(idents, vdefs)
diff --git a/test/files/pos/bug3136.scala b/test/files/pos/bug3136.scala
new file mode 100644
index 0000000000..33d42c2f3c
--- /dev/null
+++ b/test/files/pos/bug3136.scala
@@ -0,0 +1,19 @@
+class Type
+class Symbol
+case class PolyType(tps: List[Symbol], res: Type) extends Type
+class OtherType extends Type
+
+// case class NullaryMethodType(tp: Type) extends Type
+
+object NullaryMethodType {
+  def apply(resTpe: Type): Type = PolyType(List(), resTpe)
+  def unapply(tp: Type): Option[(Type)] = None
+}
+
+object Test {
+  def TEST(tp: Type): String =
+    tp match {
+      case PolyType(ps1, PolyType(ps2, res @ PolyType(a, b))) => "1"+tp // couldn't find a simpler version that still crashes
+      case NullaryMethodType(meh) => "2"+meh
+    }
+}
diff --git a/test/files/run/bug1697.scala b/test/pending/run/bug1697.scala
index 01590dd405..01590dd405 100644
--- a/test/files/run/bug1697.scala
+++ b/test/pending/run/bug1697.scala