Remove unnecessary context mode InSuperCall

After the previous commit, there was one usage of InSuperCall left in
typedIdent to provide a better error message, but that usage can be
replaced by a check to make sure we're in a secondary constructor
instead, which means we can get rid of this mode avoid having to set and
unset it in a bunch of places.

Author: smarter

compiler/src/dotty/tools/dotc/core/Contexts.scala

@@ -353,7 +353,6 @@ object Contexts {
      *  - as owner: The primary constructor of the class
      *  - as outer context: The context enclosing the class context
      *  - as scope: The parameter accessors in the class context
-     *  - with additional mode: InSuperCall
      *
      *  The reasons for this peculiar choice of attributes are as follows:
      *
@@ -394,7 +393,7 @@ object Contexts {
       var classCtx = outersIterator.dropWhile(!_.isClassDefContext).next()
       classCtx.outer.fresh.setOwner(owner)
         .setScope(locals)
-        .setMode(classCtx.mode | Mode.InSuperCall)
+        .setMode(classCtx.mode)
     }
 
     /** The context of expression `expr` seen as a member of a statement sequence */

compiler/src/dotty/tools/dotc/core/Mode.scala

@@ -43,9 +43,6 @@ object Mode {
 
   val CheckCyclic: Mode = newMode(5, "CheckCyclic")
 
-  /** We are looking at the arguments of a supercall */
-  val InSuperCall: Mode = newMode(6, "InSuperCall")
-
   /** We are in a pattern alternative */
   val InPatternAlternative: Mode = newMode(7, "InPatternAlternative")
 

compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala

@@ -780,7 +780,7 @@ class TreeUnpickler(reader: TastyReader,
             def complete(implicit ctx: Context) = typer.Inliner.bodyToInline(sym)
           }
         else
-          readLater(end, rdr => ctx => rdr.readTerm()(ctx.retractMode(Mode.InSuperCall)))
+          readLater(end, rdr => ctx => rdr.readTerm())
 
       def ValDef(tpt: Tree) =
         ta.assignType(untpd.ValDef(sym.name.asTermName, tpt, readRhs(localCtx)), sym)
@@ -1032,9 +1032,7 @@ class TreeUnpickler(reader: TastyReader,
       }
 
       def completeSelect(name: Name, sig: Signature): Select = {
-        val localCtx =
-          if (name == nme.CONSTRUCTOR) ctx.addMode(Mode.InSuperCall) else ctx
-        val qual = readTerm()(localCtx)
+        val qual = readTerm()(ctx)
         var qualType = qual.tpe.widenIfUnstable
         val denot = accessibleDenot(qualType, name, sig)
         val owner = denot.symbol.maybeOwner

compiler/src/dotty/tools/dotc/typer/Namer.scala

@@ -1021,7 +1021,7 @@ class Namer { typer: Typer =>
   class ClassCompleter(cls: ClassSymbol, original: TypeDef)(ictx: Context) extends Completer(original)(ictx) {
     withDecls(newScope)
 
-    protected implicit val ctx: Context = localContext(cls).setMode(ictx.mode &~ Mode.InSuperCall)
+    protected implicit val ctx: Context = localContext(cls)
 
     private var localCtx: Context = _
 

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -445,10 +445,9 @@ class Typer extends Namer
         return ref(defn.XMLTopScopeModule.termRef)
       else if (name.toTermName == nme.ERROR)
         UnspecifiedErrorType
-      else if (ctx.owner.isConstructor && ctx.mode.is(Mode.InSuperCall) &&
+      else if (ctx.owner.isConstructor && !ctx.owner.isPrimaryConstructor &&
           ctx.owner.owner.unforcedDecls.lookup(tree.name).exists)
-        // When InSuperCall mode and in a constructor we are in the arguments
-        // of a this(...) constructor call
+        // we are in the arguments of a this(...) constructor call
         errorType(ex"$tree is not accessible from constructor arguments", tree.sourcePos)
       else
         errorType(new MissingIdent(tree, kind, name.show), tree.sourcePos)
@@ -2191,7 +2190,7 @@ class Typer extends Namer
               typer1.typedDefDef(tree, sym)(ctx.localContext(tree, sym).setTyper(typer1))
             case tree: untpd.TypeDef =>
               if (tree.isClassDef)
-                typedClassDef(tree, sym.asClass)(ctx.localContext(tree, sym).setMode(ctx.mode &~ Mode.InSuperCall))
+                typedClassDef(tree, sym.asClass)(ctx.localContext(tree, sym))
               else
                 typedTypeDef(tree, sym)(ctx.localContext(tree, sym).setNewScope)
             case tree: untpd.Labeled => typedLabeled(tree)