Fix for SI-6664, cycle in case classes.

Scope lookup of an overloaded symbol was accidentally
forcing some lazy info. Since as usual the caller didn't
even have any interest in the symbol, but only in whether
the name existed at all, I changed it call the method I
made for this exact purpose, containsName. Also I much
reduced the number of checks being made in the quest for
an inherited copy method.

1 files changed, 3 insertions, 4 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Namers.scala b/src/compiler/scala/tools/nsc/typechecker/Namers.scala
index 3f5410eb45..04fb69671e 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Namers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Namers.scala
@@ -909,11 +909,10 @@ trait Namers extends MethodSynthesis {
         val modClass = companionSymbolOf(clazz, context).moduleClass
         modClass.attachments.get[ClassForCaseCompanionAttachment] foreach { cma =>
           val cdef = cma.caseClass
-          def hasCopy(decls: Scope) = (decls lookup nme.copy) != NoSymbol
+          def hasCopy = (decls containsName nme.copy) || parents.exists(_ member nme.copy exists)
+
           // SI-5956 needs (cdef.symbol == clazz): there can be multiple class symbols with the same name
-          if (cdef.symbol == clazz && !hasCopy(decls) &&
-                  !parents.exists(p => hasCopy(p.typeSymbol.info.decls)) &&
-                  !parents.flatMap(_.baseClasses).distinct.exists(bc => hasCopy(bc.info.decls)))
+          if (cdef.symbol == clazz && !hasCopy)
             addCopyMethod(cdef, templateNamer)
         }
       }