Omnibox: Prevent Asynchronous Suggestions from Changing Default Match

components/omnibox/search_provider.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file contains the Search autocomplete provider.  This provider is
 // responsible for all autocomplete entries that start with "Search <engine>
 // for ...", including searching for the current input string, search
 // history, and search suggestions.  An instance of it gets created and
 // managed by the autocomplete controller.
 
@@ skipping 57 matching lines @@
   void set_current_page_url(const GURL& current_page_url) {
     current_page_url_ = current_page_url;
   }
 
  protected:
   virtual ~SearchProvider();
 
  private:
   friend class SearchProviderTest;
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, CanSendURL);
+  FRIEND_TEST_ALL_PREFIXES(SearchProviderTest,
+                           DontInlineAutocompleteAsynchronously);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, NavigationInline);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, NavigationInlineDomainClassify);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, NavigationInlineSchemeSubstring);
-  FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, RemoveStaleResultsTest);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, SuggestRelevanceExperiment);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, TestDeleteMatch);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, SuggestQueryUsesToken);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, SessionToken);
   FRIEND_TEST_ALL_PREFIXES(SearchProviderTest, AnswersCache);
   FRIEND_TEST_ALL_PREFIXES(AutocompleteProviderTest, GetDestinationURL);
   FRIEND_TEST_ALL_PREFIXES(InstantExtendedPrefetchTest, ClearPrefetchedResults);
   FRIEND_TEST_ALL_PREFIXES(InstantExtendedPrefetchTest, SetPrefetchQuery);
 
   // Manages the providers (TemplateURLs) used by SearchProvider. Two providers
@@ skipping 40 matching lines @@
     base::string16 default_provider_;
     base::string16 keyword_provider_;
 
     DISALLOW_COPY_AND_ASSIGN(Providers);
   };
 
   class CompareScoredResults;
 
   typedef std::vector<history::KeywordSearchTermVisit> HistoryResults;
 
-  // Removes non-inlineable results until either the top result can inline
-  // autocomplete the current input or verbatim outscores the top result.
-  static void RemoveStaleResults(
-      const base::string16& input,
-      int verbatim_relevance,
-      SearchSuggestionParser::SuggestResults* suggest_results,
-      SearchSuggestionParser::NavigationResults* navigation_results);
-
   // Calculates the relevance score for the keyword verbatim result (if the
   // input matches one of the profile's keyword).
   static int CalculateRelevanceForKeywordVerbatim(
       metrics::OmniboxInputType::Type type,
       bool prefer_keyword);
 
+  // A helper function for UpdateAllOldResults().
+  static void UpdateOldResults(bool minimal_changes,
+                               SearchSuggestionParser::Results* results);
+
+  // Returns the first match in |matches| which might be chosen as default.
+  static ACMatches::iterator FindTopMatch(ACMatches* matches);
+
   // AutocompleteProvider:
   virtual void Start(const AutocompleteInput& input,
                      bool minimal_changes) OVERRIDE;
   virtual void Stop(bool clear_cached_results) OVERRIDE;
 
   // BaseSearchProvider:
   virtual const TemplateURL* GetTemplateURL(bool is_keyword) const OVERRIDE;
   virtual const AutocompleteInput GetInput(bool is_keyword) const OVERRIDE;
   virtual bool ShouldAppendExtraParams(
       const SearchSuggestionParser::SuggestResult& result) const OVERRIDE;
@@ skipping 34 matching lines @@
   // Determines whether an asynchronous subcomponent query should run for the
   // current input.  If so, starts it if necessary; otherwise stops it.
   // NOTE: This function does not update |done_|.  Callers must do so.
   void StartOrStopSuggestQuery(bool minimal_changes);
 
   // Returns true when the current query can be sent to the Suggest service.
   // This will be false e.g. when Suggest is disabled, the query contains
   // potentially private data, etc.
   bool IsQuerySuitableForSuggest() const;
 
-  // Removes stale results for both default and keyword providers.  See comments
-  // on RemoveStaleResults().
-  void RemoveAllStaleResults();
+  // Remove existing keyword results if the user is no longer in keyword mode,
+  // and, if |minimal_changes| is false, revise the existing results to
+  // indicate they were received before the last keystroke.
+  void UpdateAllOldResults(bool minimal_changes);
+
+  // Given new asynchronous results, ensure that we don't clobber the current
+  // top results, which were determined synchronously on the last keystroke.
+  void PersistTopSuggestions(SearchSuggestionParser::Results* results);
 
   // Apply calculated relevance scores to the current results.
-  void ApplyCalculatedRelevance();
   void ApplyCalculatedSuggestRelevance(
       SearchSuggestionParser::SuggestResults* list);
   void ApplyCalculatedNavigationRelevance(
       SearchSuggestionParser::NavigationResults* list);
 
   // Starts a new URLFetcher requesting suggest results from |template_url|;
   // callers own the returned URLFetcher, which is NULL for invalid providers.
   net::URLFetcher* CreateSuggestFetcher(int id,
                                         const TemplateURL* template_url,
                                         const AutocompleteInput& input);
@@ skipping 118 matching lines @@
   base::TimeTicks time_suggest_request_sent_;
 
   // Fetchers used to retrieve results for the keyword and default providers.
   scoped_ptr<net::URLFetcher> keyword_fetcher_;
   scoped_ptr<net::URLFetcher> default_fetcher_;
 
   // Results from the default and keyword search providers.
   SearchSuggestionParser::Results default_results_;
   SearchSuggestionParser::Results keyword_results_;
 
+  // The top query suggestion, left blank if none.
+  base::string16 top_query_suggestion_match_contents_;
+  // The top navigation suggestion, left blank/invalid if none.
+  GURL top_navigation_suggestion_;
+
   GURL current_page_url_;
 
   // Session token management.
   std::string current_token_;
   base::TimeTicks token_expiration_time_;
 
   // Answers prefetch management.
   AnswersCache answers_cache_;  // Cache for last answers seen.
   AnswersQueryData prefetch_data_;  // Data to use for query prefetching.
 
   DISALLOW_COPY_AND_ASSIGN(SearchProvider);
 };
 
 #endif  // COMPONENTS_OMNIBOX_SEARCH_PROVIDER_H_