First versions of Definitions based on TypeRefs not Symbols.

Symbols are not stable between runs, so if some symbol referred
to from Definitions gets recompiled, there are then two Symbols
that are both visible, one referenced from Definitions, the other
the one that got compiled.

Thos led to a crash when e.g. compiling scala.Short, because the
newly compiled symbol was not recognized as a primitive value
class.

The present commit tries to make systematic changes without regard
to simplicity or aesthetics. This will be polished in future commits.
// ### comments signal areas that need further attention.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/dotty/tools/dotc/core/Denotations.scala b/src/dotty/tools/dotc/core/Denotations.scala
index 65df55a9d..666908fab 100644
--- a/src/dotty/tools/dotc/core/Denotations.scala
+++ b/src/dotty/tools/dotc/core/Denotations.scala
@@ -207,14 +207,20 @@ object Denotations {
 
     def requiredMethod(name: PreName)(implicit ctx: Context): TermSymbol =
       info.member(name.toTermName).requiredSymbol(_ is Method).asTerm
+    def requiredMethodRef(name: PreName)(implicit ctx: Context): TermRef =
+      requiredMethod(name).termRef
 
     def requiredMethod(name: PreName, argTypes: List[Type])(implicit ctx: Context): TermSymbol =
       info.member(name.toTermName).requiredSymbol(x=>
         (x is Method) && x.info.paramTypess == List(argTypes)
       ).asTerm
+    def requiredMethodRef(name: PreName, argTypes: List[Type])(implicit ctx: Context): TermRef =
+      requiredMethod(name, argTypes).termRef
 
     def requiredValue(name: PreName)(implicit ctx: Context): TermSymbol =
       info.member(name.toTermName).requiredSymbol(_.info.isParameterless).asTerm
+    def requiredValueRef(name: PreName)(implicit ctx: Context): TermRef =
+      requiredValue(name).termRef
 
     def requiredClass(name: PreName)(implicit ctx: Context): ClassSymbol =
       info.member(name.toTypeName).requiredSymbol(_.isClass).asClass