Fix #3775: Fix RefChecks#upwardsThisType

smarter · smarter · commit 04ece0cd1c36 · 2018-01-08T18:25:35.000+01:00
A non-applied class TypeRef is not a valid prefix for a TypeRef of a
class type parameter, it causes an assertion error in NamedType#argDenot
because args.nonEmpty ends up false.
diff --git a/compiler/src/dotty/tools/dotc/typer/RefChecks.scala b/compiler/src/dotty/tools/dotc/typer/RefChecks.scala
@@ -86,7 +86,7 @@ object RefChecks {
    */
   private def upwardsThisType(cls: Symbol)(implicit ctx: Context) = cls.info match {
     case ClassInfo(_, _, _, _, tp: Type) if (tp ne cls.typeRef) && !cls.is(ModuleOrFinal) =>
-      SkolemType(cls.typeRef).withName(nme.this_)
+      SkolemType(cls.appliedRef).withName(nme.this_)
     case _ =>
       cls.thisType
   }

Original file line number	Diff line number	Diff line change
`@@ -86,7 +86,7 @@ object RefChecks {`
`86`	`86`	`*/`
`87`	`87`	`private def upwardsThisType(cls: Symbol)(implicit ctx: Context) = cls.info match {`
`88`	`88`	`case ClassInfo(_, _, _, _, tp: Type) if (tp ne cls.typeRef) && !cls.is(ModuleOrFinal) =>`
`89`		`- SkolemType(cls.typeRef).withName(nme.this_)`
	`89`	`+ SkolemType(cls.appliedRef).withName(nme.this_)`
`90`	`90`	`case _ =>`
`91`	`91`	`cls.thisType`
`92`	`92`	`}`