Handle private fields from mixins.

sdk/lib/_internal/compiler/implementation/elements/modelx.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library elements.modelx;
 
 import 'dart:uri';
 import 'dart:collection' show LinkedHashMap;
 
 import 'elements.dart';
@@ skipping 1512 matching lines @@
    * When called on the implementation element both members declared in the
    * origin and the patch class are returned.
    */
   Element lookupSelector(Selector selector) {
     return internalLookupSelector(selector, false);
   }
 
   Element lookupSuperSelector(Selector selector) {
     return internalLookupSelector(selector, true);
   }
-  
+
   Element internalLookupSelector(Selector selector, bool isSuperLookup) {
     SourceString name = selector.name;
     bool isPrivate = name.isPrivate();
     LibraryElement library = selector.library;
     for (ClassElement current = isSuperLookup ? superclass : this;
          current != null;
          current = current.superclass) {
       Element member = current.lookupLocalMember(name);
       if (member == null) continue;
       // Private members from a different library are not visible.
@@ skipping 32 matching lines @@
   }
 
   /**
    * Returns true if the [fieldMember] is shadowed by another field. The given
    * [fieldMember] must be a member of this class.
    *
    * This method also works if the [fieldMember] is private.
    */
   bool isShadowedByField(Element fieldMember) {
     assert(fieldMember.isField());
-    // Note that we cannot use [lookupMember] or [lookupSuperMember] since it
-    // will not do the right thing for private elements.
+    SourceString fieldName = fieldMember.name;
+    bool isPrivate = fieldName.isPrivate();
+    LibraryElement memberLibrary = fieldMember.getLibrary();
     ClassElement lookupClass = this;
-    LibraryElement memberLibrary = fieldMember.getLibrary();
-    if (fieldMember.name.isPrivate()) {
-      // We find a super class in the same library as the field. This way the
-      // lookupMember will work.
-      while (lookupClass.getLibrary() != memberLibrary) {
-        lookupClass = lookupClass.superclass;
+    while (lookupClass != null) {
+      Element foundMember = lookupClass.lookupLocalMember(fieldName);
+      if (foundMember != null) {
+        if (foundMember == fieldMember) return false;
+        if (foundMember.isField()) {
+          if (!isPrivate || memberLibrary == foundMember.getLibrary()) {
+            // Private fields can only be shadowed by a field declared
+            // in the same library.
+            return true;
+          }
+        }
       }
+      lookupClass = lookupClass.superclass;
     }
-    SourceString fieldName = fieldMember.name;
-    while (true) {
-      Element foundMember = lookupClass.lookupMember(fieldName);
-      if (foundMember == fieldMember) return false;
-      if (foundMember.isField()) return true;
-      lookupClass = foundMember.getEnclosingClass().superclass;
-    }
+    return false;
   }
 
   Element validateConstructorLookupResults(Selector selector,
                                            Element result,
                                            Element noMatch(Element)) {
     if (result == null
         || !result.isConstructor()
         || (selector.name.isPrivate()
             && result.getLibrary() != selector.library)) {
       result = noMatch != null ? noMatch(result) : null;
@@ skipping 404 matching lines @@
 
   MetadataAnnotation ensureResolved(Compiler compiler) {
     if (resolutionState == STATE_NOT_STARTED) {
       compiler.resolver.resolveMetadataAnnotation(this);
     }
     return this;
   }
 
   String toString() => 'MetadataAnnotation($value, $resolutionState)';
 }