remove duplicate completion suggestions

pkg/analysis_server/lib/src/services/completion/imported_computer.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 services.completion.computer.dart.toplevel;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analysis_server/src/protocol_server.dart'
@@ skipping 62 matching lines @@
 /**
  * [_ImportedSuggestionBuilder] traverses the imports and builds suggestions
  * based upon imported elements.
  */
 class _ImportedSuggestionBuilder extends ElementSuggestionBuilder
     implements SuggestionBuilder {
   bool shouldWaitForLowPrioritySuggestions;
   final DartCompletionRequest request;
   final OpType optype;
   DartCompletionCache cache;
+  HashSet<String> completions;
 
   _ImportedSuggestionBuilder(this.request, this.optype) {
     cache = request.cache;
+    completions = new HashSet<String>();
+    for (CompletionSuggestion suggestion in request.suggestions) {
+      completions.add(suggestion.completion);
+    }
   }
 
   @override
   CompletionSuggestionKind get kind => CompletionSuggestionKind.INVOCATION;
 
   /**
    * If the needed information is cached, then add suggestions and return `true`
    * else return `false` indicating that additional work is necessary.
    */
   bool computeFast(AstNode node) {
@@ skipping 67 matching lines @@
 
   /**
    * Add suggestions which start with the given text.
    */
   _addFilteredSuggestions(
       String filterText, List<CompletionSuggestion> unfiltered) {
     //TODO (danrubel) Revisit this filtering once paged API has been added
     unfiltered.forEach((CompletionSuggestion suggestion) {
       if (filterText.length > 0) {
         if (suggestion.completion.startsWith(filterText)) {
-          request.suggestions.add(suggestion);
+          _addSuggestion(suggestion);
         }
       } else {
         if (suggestion.relevance != DART_RELEVANCE_LOW) {
-          request.suggestions.add(suggestion);
+          _addSuggestion(suggestion);
         }
       }
     });
   }
 
   /**
    * Add suggestions for any inherited imported members.
    */
   void _addInheritedSuggestions(AstNode node) {
     var classDecl = node.getAncestor((p) => p is ClassDeclaration);
@@ skipping 26 matching lines @@
               _addElementSuggestions(type.element.methods,
                   relevance: DART_RELEVANCE_INHERITED_METHOD);
             }
           });
         }
       }
     }
   }
 
   /**
+   * Add suggestion if an identically named suggestion
+   * has not already been added.
+   */
+  void _addSuggestion(CompletionSuggestion suggestion) {
+    if (completions.add(suggestion.completion)) {
+      request.suggestions.add(suggestion);
+    }
+  }
+
+  /**
    * Add suggested based upon imported elements.
    */
   void _addSuggestions(AstNode node) {
     if (optype.includeConstructorSuggestions) {
       _addConstructorSuggestions();
     }
     if (optype.includeReturnValueSuggestions ||
         optype.includeTypeNameSuggestions ||
         optype.includeVoidReturnSuggestions) {
       _addInheritedSuggestions(node);
@@ skipping 19 matching lines @@
       _addFilteredSuggestions(filterText, cache.libraryPrefixSuggestions);
     }
     if (optype.includeReturnValueSuggestions) {
       _addFilteredSuggestions(filterText, cache.otherImportedSuggestions);
     }
     if (optype.includeVoidReturnSuggestions) {
       _addFilteredSuggestions(filterText, cache.importedVoidReturnSuggestions);
     }
   }
 }