Quick-fix non-idempotent code generated by pattern match

Author: nicolasstucki

compiler/src/dotty/tools/dotc/transform/PatternMatcher.scala

@@ -3,7 +3,7 @@ package transform
 
 import core._
 import MegaPhase._
-import collection.mutable
+import scala.collection.mutable
 import SymDenotations._, Symbols._, Contexts._, Types._, Names._, StdNames._, NameOps._
 import ast.Trees._
 import util.Positions._
@@ -700,7 +700,7 @@ object PatternMatcher {
           }
           val newArgs =
             for {
-              (rhs, actual) <- seenVars.toList
+              (rhs, actual) <- seenVars.toList.sortBy(_._2.toString)
               formal <- paramsOfLabel(plan.label).get(rhs)
             }
             yield (formal -> actual)