Fix for issue 22110

pkg/analyzer/lib/src/generated/resolver.dart

 // Copyright (c) 2014, 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 engine.resolver;
 
 import "dart:math" as math;
 import 'dart:collection';
 
 import 'package:analyzer/src/generated/utilities_collection.dart';
@@ skipping 4184 matching lines @@
             return false;
           }
         }
         // For switch members with no statements, don't visit the children,
         // otherwise, return false if no return is found in the children
         // statements.
         if (!switchMember.statements.isEmpty && !switchMember.accept(this)) {
           return false;
         }
       }
+      // All of the members exit, determine whether there are possible cases
+      // that are not caught by the members.
+      DartType type = node.expression == null ? null : node.expression.bestType;
+      if (type is InterfaceType) {
+        ClassElement element = type.element;
+        if (element != null && element.isEnum) {
+          // If some of the enum values are not covered, then a warning will
+          // have already been generated, so there's no point in generating a
+          // hint.
+          return true;
+        }
+      }
       return hasDefault;
     } finally {
       _enclosingBlockContainsBreak = outerBreakValue;
     }
   }
 
   @override
   bool visitThisExpression(ThisExpression node) => false;
 
   @override
@@ skipping 11460 matching lines @@
    * library.
    */
   final HashSet<String> members = new HashSet<String>();
 
   /**
    * Names of resolved or unresolved class members that are read in the
    * library.
    */
   final HashSet<String> readMembers = new HashSet<String>();
 }