Omnibox - Boost Frequency Scores Based on Number of Matching Pages

components/omnibox/browser/url_index_private_data.cc

 // 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.
 
 #include "components/omnibox/browser/url_index_private_data.h"
 
 #include <stdint.h>
 
 #include <functional>
 #include <iterator>
@@ skipping 696 matching lines @@
     it = std::find_if(it, history_id_set.end(),
                       [this, template_url_service](const HistoryID history_id) {
                         return ShouldFilter(history_id, template_url_service);
                       });
     if (it == history_id_set.end())
       break;
     it = history_id_set.erase(it);
   }
 
   // Score the matches.
+  const size_t num_matches = history_id_set.size();
   const base::Time now = base::Time::Now();
   std::transform(
       history_id_set.begin(), history_id_set.end(),
       std::back_inserter(*scored_items),
       [this, &lower_raw_string, &lower_raw_terms,
-       &lower_terms_to_word_starts_offsets, &bookmark_model,
+       &lower_terms_to_word_starts_offsets, &bookmark_model, &num_matches,
        &now](const HistoryID history_id) {

[Peter Kasting, 2016/12/01 07:07:53]

Nit: Bleh, I'm inclined to replace this huge list of captures with just [&].

[Mark P, 2016/12/04 01:06:42]

Done.

         auto hist_pos = history_info_map_.find(history_id);
         const history::URLRow& hist_item = hist_pos->second.url_row;
         auto starts_pos = word_starts_map_.find(history_id);
         DCHECK(starts_pos != word_starts_map_.end());
         return ScoredHistoryMatch(
             hist_item, hist_pos->second.visits, lower_raw_string,
             lower_raw_terms, lower_terms_to_word_starts_offsets,
             starts_pos->second,
             bookmark_model && bookmark_model->IsBookmarked(hist_item.url()),
-            now);
+            num_matches, now);
       });
 
   // Filter all matches that ended up scoring 0.  (These are usually matches
   // which didn't match the user's raw terms.)
   scored_items->erase(std::remove_if(scored_items->begin(), scored_items->end(),
                                      [](const ScoredHistoryMatch& match) {
                                        return match.raw_score == 0;
                                      }),
                       scored_items->end());
 }
@@ skipping 638 matching lines @@
   // First cut: typed count, visit count, recency.
   // TODO(mrossetti): This is too simplistic. Consider an approach which ranks
   // recently visited (within the last 12/24 hours) as highly important. Get
   // input from mpearson.
   if (r1.typed_count() != r2.typed_count())
     return (r1.typed_count() > r2.typed_count());
   if (r1.visit_count() != r2.visit_count())
     return (r1.visit_count() > r2.visit_count());
   return (r1.last_visit() > r2.last_visit());
 }