Prefer lookup in package to special casing

Author: som-snytt

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

@@ -370,22 +370,15 @@ class CheckUnused private (phaseMode: PhaseMode, suffix: String) extends MiniPha
     var cachePoint: Context = NoContext // last context with Resolved cache
     var importer: ImportSelector | Null = null // non-null for import context
     var precedence = NoPrecedence // of current resolution
+    var enclosed = false // true if sym is owner of an enclosing context
     var done = false
     var cached = false
     val ctxs = ctx.outersIterator
     while !done && ctxs.hasNext do
       val cur = ctxs.next()
-      if cur.owner.userSymbol eq sym then
-        if sym.is(Package) then
-          if cur.isSimplePackage then
-            precedence = Definition
-            importer = null
-          // else package p.q is not available as a simple name but it might be imported
-          end if
-          done = true
-        else
-          return // found enclosing definition, don't register the reference
-      else if isLocal then
+      if cur.owner.userSymbol == sym && !sym.is(Package) then
+        enclosed = true // found enclosing definition, don't register the reference
+      if isLocal then
         if cur.owner eq sym.owner then
           done = true // for local def, just checking that it is not enclosing
       else
@@ -426,7 +419,7 @@ class CheckUnused private (phaseMode: PhaseMode, suffix: String) extends MiniPha
                 candidate = cur
                 importer = sel
         else if checkMember(cur.owner) then
-          if sym.srcPos.sourcePos.source == ctx.source then
+          if sym.is(Package) || sym.srcPos.sourcePos.source == ctx.source then
             precedence = Definition
             candidate = cur
             importer = null // ignore import in same scope; we can't check nesting level
@@ -436,7 +429,8 @@ class CheckUnused private (phaseMode: PhaseMode, suffix: String) extends MiniPha
             candidate = cur
     end while
     // record usage and possibly an import
-    refInfos.refs.addOne(sym)
+    if !enclosed then
+      refInfos.refs.addOne(sym)
     if candidate != NoContext && candidate.isImportContext && importer != null then
       refInfos.sels.put(importer, ())
     // possibly record that we have performed this look-up
@@ -970,23 +964,6 @@ object CheckUnused:
     inline def userSymbol: Symbol=
       if sym.denot.is(ModuleClass) then sym.denot.companionModule else sym
 
-  extension (cur: Context)
-    def isSimplePackage(using Context): Boolean = cur.owner.is(Package) && {
-      val location = cur.owner.showFullName
-      val enclosing = cur.outersIterator
-        .takeWhile(c => !c.owner.isEmptyPackage && !(c.isImportContext && c.importInfo.nn.isRootImport))
-        .find(c => c.owner.userSymbol ne cur.owner.userSymbol)
-      enclosing match
-      case Some(outer) =>
-        outer.owner.is(Package) // if there is such an outer context, its owner should be package
-        && !location
-            .stripPrefix(outer.owner.showFullName) // p.q in p.q.r
-            .stripPrefix(".") // leading dot in .r
-            .contains(".") // remaining r so p.q.v.w leaves v.w
-      case _ =>
-        !location.contains(".") // no outer context contributes a name, effectively _root_.p.q
-    }
-
   extension (sel: ImportSelector)
     def boundTpe: Type = sel.bound match
       case untpd.TypedSplice(tree) => tree.tpe