Create Private Data for InMemoryURLIndex (in Preparation for SQLite Cache)

chrome/browser/history/in_memory_url_index_unittest.cc

Index: chrome/browser/history/in_memory_url_index_unittest.cc
===================================================================
--- chrome/browser/history/in_memory_url_index_unittest.cc	(revision 106401)
+++ chrome/browser/history/in_memory_url_index_unittest.cc	(working copy)
@@ -2,24 +2,18 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include <stdio.h>
-
 #include <fstream>
-#include <string>
-#include <vector>
 
 #include "base/file_path.h"
 #include "base/file_util.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
+#include "base/string16.h"
 #include "base/string_util.h"
-#include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/history/in_memory_database.h"
 #include "chrome/browser/history/in_memory_url_index.h"
+#include "chrome/browser/history/in_memory_url_index_types.h"
 #include "chrome/common/chrome_paths.h"
-#include "sql/connection.h"
-#include "sql/statement.h"
 #include "sql/transaction.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -59,9 +53,8 @@
                     int typed_count);
 
   // Convenience functions for easily creating vectors of search terms.
-  InMemoryURLIndex::String16Vector Make1Term(const char* term) const;
-  InMemoryURLIndex::String16Vector Make2Terms(const char* term_1,
-                                              const char* term_2) const;
+  String16Vector Make1Term(const char* term) const;
+  String16Vector Make2Terms(const char* term_1, const char* term_2) const;
 
   // Validates that the given |term| is contained in |cache| and that it is
   // marked as in-use.
@@ -145,20 +138,18 @@
   return row;
 }
 
-InMemoryURLIndex::String16Vector InMemoryURLIndexTest::Make1Term(
-    const char* term) const {
-  InMemoryURLIndex::String16Vector terms;
-  terms.push_back(UTF8ToUTF16(term));
-  return terms;
+String16Vector InMemoryURLIndexTest::Make1Term(const char* term) const {
+  String16Vector original_terms;
+  original_terms.push_back(UTF8ToUTF16(term));
+  return original_terms;
 }
 
-InMemoryURLIndex::String16Vector InMemoryURLIndexTest::Make2Terms(
-    const char* term_1,
-    const char* term_2) const {
-  InMemoryURLIndex::String16Vector terms;
-  terms.push_back(UTF8ToUTF16(term_1));
-  terms.push_back(UTF8ToUTF16(term_2));
-  return terms;
+String16Vector InMemoryURLIndexTest::Make2Terms(const char* term_1,
+                                                const char* term_2) const {
+  String16Vector original_terms;
+  original_terms.push_back(UTF8ToUTF16(term_1));
+  original_terms.push_back(UTF8ToUTF16(term_2));
+  return original_terms;
 }
 
 void InMemoryURLIndexTest::CheckTerm(
@@ -173,6 +164,27 @@
       << "Cache item '" << term << "' should be marked as being in use.";
 }
 
+// Helper function which compares two maps for equivalence. The maps' values
+// are associative containers and their contents are compared as well.
+template<typename T>
+void ExpectMapOfContainersIdentical(const T& expected, const T& actual) {
+  ASSERT_EQ(expected.size(), actual.size());
+  for (typename T::const_iterator expected_iter = expected.begin();
+       expected_iter != expected.end(); ++expected_iter) {
+    typename T::const_iterator actual_iter = actual.find(expected_iter->first);
+    ASSERT_NE(actual.end(), actual_iter);
+    typename T::mapped_type const& expected_values(expected_iter->second);
+    typename T::mapped_type const& actual_values(actual_iter->second);
+    ASSERT_EQ(expected_values.size(), actual_values.size());
+    for (typename T::mapped_type::const_iterator set_iter =
+         expected_values.begin(); set_iter != expected_values.end(); ++set_iter)
+      EXPECT_EQ(actual_values.count(*set_iter),
+                expected_values.count(*set_iter));
+  }
+}
+
+//------------------------------------------------------------------------------
+
 class LimitedInMemoryURLIndexTest : public InMemoryURLIndexTest {
  protected:
   FilePath::StringType TestDBName() const;
@@ -217,12 +229,12 @@
   EXPECT_EQ(1U, row_count);
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
-  EXPECT_EQ(1, url_index_->history_item_count_);
+  URLIndexPrivateData& private_data(*(url_index_->private_data_));
 
   // history_info_map_ should have the same number of items as were filtered.
-  EXPECT_EQ(1U, url_index_->history_info_map_.size());
-  EXPECT_EQ(35U, url_index_->char_word_map_.size());
-  EXPECT_EQ(17U, url_index_->word_map_.size());
+  EXPECT_EQ(1U, private_data.history_info_map_.size());
+  EXPECT_EQ(35U, private_data.char_word_map_.size());
+  EXPECT_EQ(17U, private_data.word_map_.size());
 }
 
 TEST_F(InMemoryURLIndexTest, Retrieval) {
@@ -259,11 +271,11 @@
             matches[0].url_info.title());
 
   // Search which should result in very poor result.
-  InMemoryURLIndex::String16Vector terms;
-  terms.push_back(ASCIIToUTF16("z"));
-  terms.push_back(ASCIIToUTF16("y"));
-  terms.push_back(ASCIIToUTF16("x"));
-  matches = url_index_->HistoryItemsForTerms(terms);
+  String16Vector original_terms;
+  original_terms.push_back(ASCIIToUTF16("z"));
+  original_terms.push_back(ASCIIToUTF16("y"));
+  original_terms.push_back(ASCIIToUTF16("x"));
+  matches = url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(1U, matches.size());
   // The results should have a poor score.
   EXPECT_LT(matches[0].raw_score, 500);
@@ -296,14 +308,15 @@
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
   // Signal if someone has changed the test DB.
-  EXPECT_EQ(27U, url_index_->history_info_map_.size());
-  InMemoryURLIndex::String16Vector terms;
+  EXPECT_EQ(27U, url_index_->private_data_->history_info_map_.size());
+  String16Vector original_terms;
 
   // Ensure title is being searched.
-  terms.push_back(ASCIIToUTF16("MORTGAGE"));
-  terms.push_back(ASCIIToUTF16("RATE"));
-  terms.push_back(ASCIIToUTF16("DROPS"));
-  ScoredHistoryMatches matches = url_index_->HistoryItemsForTerms(terms);
+  original_terms.push_back(ASCIIToUTF16("MORTGAGE"));
+  original_terms.push_back(ASCIIToUTF16("RATE"));
+  original_terms.push_back(ASCIIToUTF16("DROPS"));
+  ScoredHistoryMatches matches =
+      url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(1U, matches.size());
 
   // Verify that we got back the result we expected.
@@ -315,6 +328,54 @@
       matches[0].url_info.title());
 }
 
+TEST_F(InMemoryURLIndexTest, TitleChange) {
+  url_index_.reset(new InMemoryURLIndex(FilePath()));
+  url_index_->Init(this, "en,ja,hi,zh");
+
+  // Verify current title terms retrieves desired item.
+  String16Vector original_terms;
+  original_terms.push_back(ASCIIToUTF16("lebronomics"));
+  original_terms.push_back(ASCIIToUTF16("could"));
+  original_terms.push_back(ASCIIToUTF16("high"));
+  original_terms.push_back(ASCIIToUTF16("taxes"));
+  original_terms.push_back(ASCIIToUTF16("influence"));
+  ScoredHistoryMatches matches =
+      url_index_->HistoryItemsForTerms(original_terms);
+  ASSERT_EQ(1U, matches.size());
+
+  // Verify that we got back the result we expected.
+  const URLID expected_id = 3;
+  EXPECT_EQ(expected_id, matches[0].url_info.id());
+  EXPECT_EQ("http://www.businessandmedia.org/articles/2010/20100708120415.aspx",
+            matches[0].url_info.url().spec());
+  EXPECT_EQ(ASCIIToUTF16(
+      "LeBronomics: Could High Taxes Influence James' Team Decision?"),
+      matches[0].url_info.title());
+  URLRow old_row(matches[0].url_info);
+
+  // Verify new title terms retrieves nothing.
+  String16Vector new_terms;
+  new_terms.push_back(ASCIIToUTF16("does"));
+  new_terms.push_back(ASCIIToUTF16("eat"));
+  new_terms.push_back(ASCIIToUTF16("oats"));
+  new_terms.push_back(ASCIIToUTF16("little"));
+  new_terms.push_back(ASCIIToUTF16("lambs"));
+  new_terms.push_back(ASCIIToUTF16("ivy"));
+  matches = url_index_->HistoryItemsForTerms(new_terms);
+  ASSERT_EQ(0U, matches.size());
+
+  // Update the row.
+  old_row.set_title(ASCIIToUTF16("Does eat oats and little lambs eat ivy"));
+  url_index_->UpdateURL(expected_id, old_row);
+
+  // Verify we get the row using the new terms but not the original terms.
+  matches = url_index_->HistoryItemsForTerms(new_terms);
+  ASSERT_EQ(1U, matches.size());
+  EXPECT_EQ(expected_id, matches[0].url_info.id());
+  matches = url_index_->HistoryItemsForTerms(original_terms);
+  ASSERT_EQ(0U, matches.size());
+}
+
 TEST_F(InMemoryURLIndexTest, NonUniqueTermCharacterSets) {
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
@@ -345,101 +406,6 @@
   EXPECT_EQ(28, matches[0].url_info.id());
 }
 
-TEST_F(InMemoryURLIndexTest, StaticFunctions) {
-  // Test WordVectorFromString16
-  string16 string_a(ASCIIToUTF16("http://www.google.com/ frammy the brammy"));
-  InMemoryURLIndex::String16Vector string_vec =
-      InMemoryURLIndex::WordVectorFromString16(string_a, false);
-  ASSERT_EQ(7U, string_vec.size());
-  // See if we got the words we expected.
-  EXPECT_EQ(UTF8ToUTF16("http"), string_vec[0]);
-  EXPECT_EQ(UTF8ToUTF16("www"), string_vec[1]);
-  EXPECT_EQ(UTF8ToUTF16("google"), string_vec[2]);
-  EXPECT_EQ(UTF8ToUTF16("com"), string_vec[3]);
-  EXPECT_EQ(UTF8ToUTF16("frammy"), string_vec[4]);
-  EXPECT_EQ(UTF8ToUTF16("the"), string_vec[5]);
-  EXPECT_EQ(UTF8ToUTF16("brammy"), string_vec[6]);
-
-  string_vec = InMemoryURLIndex::WordVectorFromString16(string_a, true);
-  ASSERT_EQ(5U, string_vec.size());
-  EXPECT_EQ(UTF8ToUTF16("http://"), string_vec[0]);
-  EXPECT_EQ(UTF8ToUTF16("www.google.com/"), string_vec[1]);
-  EXPECT_EQ(UTF8ToUTF16("frammy"), string_vec[2]);
-  EXPECT_EQ(UTF8ToUTF16("the"), string_vec[3]);
-  EXPECT_EQ(UTF8ToUTF16("brammy"), string_vec[4]);
-
-  // Test WordSetFromString16
-  string16 string_b(ASCIIToUTF16(
-      "http://web.google.com/search Google Web Search"));
-  InMemoryURLIndex::String16Set string_set =
-      InMemoryURLIndex::WordSetFromString16(string_b);
-  EXPECT_EQ(5U, string_set.size());
-  // See if we got the words we expected.
-  EXPECT_TRUE(string_set.find(UTF8ToUTF16("com")) != string_set.end());
-  EXPECT_TRUE(string_set.find(UTF8ToUTF16("google")) != string_set.end());
-  EXPECT_TRUE(string_set.find(UTF8ToUTF16("http")) != string_set.end());
-  EXPECT_TRUE(string_set.find(UTF8ToUTF16("search")) != string_set.end());
-  EXPECT_TRUE(string_set.find(UTF8ToUTF16("web")) != string_set.end());
-
-  // Test SortAndDeoverlap
-  TermMatches matches_a;
-  matches_a.push_back(TermMatch(1, 13, 10));
-  matches_a.push_back(TermMatch(2, 23, 10));
-  matches_a.push_back(TermMatch(3, 3, 10));
-  matches_a.push_back(TermMatch(4, 40, 5));
-  TermMatches matches_b = InMemoryURLIndex::SortAndDeoverlap(matches_a);
-  // Nothing should have been eliminated.
-  EXPECT_EQ(matches_a.size(), matches_b.size());
-  // The order should now be 3, 1, 2, 4.
-  EXPECT_EQ(3, matches_b[0].term_num);
-  EXPECT_EQ(1, matches_b[1].term_num);
-  EXPECT_EQ(2, matches_b[2].term_num);
-  EXPECT_EQ(4, matches_b[3].term_num);
-  matches_a.push_back(TermMatch(5, 18, 10));
-  matches_a.push_back(TermMatch(6, 38, 5));
-  matches_b = InMemoryURLIndex::SortAndDeoverlap(matches_a);
-  // Two matches should have been eliminated.
-  EXPECT_EQ(matches_a.size() - 2, matches_b.size());
-  // The order should now be 3, 1, 2, 6.
-  EXPECT_EQ(3, matches_b[0].term_num);
-  EXPECT_EQ(1, matches_b[1].term_num);
-  EXPECT_EQ(2, matches_b[2].term_num);
-  EXPECT_EQ(6, matches_b[3].term_num);
-
-  // Test MatchTermInString
-  TermMatches matches_c = InMemoryURLIndex::MatchTermInString(
-      UTF8ToUTF16("x"), UTF8ToUTF16("axbxcxdxex fxgx/hxixjx.kx"), 123);
-  ASSERT_EQ(11U, matches_c.size());
-  const size_t expected_offsets[] = { 1, 3, 5, 7, 9, 12, 14, 17, 19, 21, 24 };
-  for (int i = 0; i < 11; ++i)
-    EXPECT_EQ(expected_offsets[i], matches_c[i].offset);
-}
-
-TEST_F(InMemoryURLIndexTest, OffsetsAndTermMatches) {
-  // Test OffsetsFromTermMatches
-  history::TermMatches matches_a;
-  matches_a.push_back(history::TermMatch(1, 1, 2));
-  matches_a.push_back(history::TermMatch(2, 4, 3));
-  matches_a.push_back(history::TermMatch(3, 9, 1));
-  matches_a.push_back(history::TermMatch(3, 10, 1));
-  matches_a.push_back(history::TermMatch(4, 14, 5));
-  std::vector<size_t> offsets =
-      InMemoryURLIndex::OffsetsFromTermMatches(matches_a);
-  const size_t expected_offsets_a[] = {1, 4, 9, 10, 14};
-  ASSERT_EQ(offsets.size(), arraysize(expected_offsets_a));
-  for (size_t i = 0; i < offsets.size(); ++i)
-    EXPECT_EQ(expected_offsets_a[i], offsets[i]);
-
-  // Test ReplaceOffsetsInTermMatches
-  offsets[2] = string16::npos;
-  history::TermMatches matches_b =
-      InMemoryURLIndex::ReplaceOffsetsInTermMatches(matches_a, offsets);
-  const size_t expected_offsets_b[] = {1, 4, 10, 14};
-  ASSERT_EQ(arraysize(expected_offsets_b), matches_b.size());
-  for (size_t i = 0; i < matches_b.size(); ++i)
-    EXPECT_EQ(expected_offsets_b[i], matches_b[i].offset);
-}
-
 TEST_F(InMemoryURLIndexTest, TypedCharacterCaching) {
   // Verify that match results for previously typed characters are retained
   // (in the term_char_word_set_cache_) and reused, if possible, in future
@@ -460,55 +426,55 @@
 
   // Simulate typing "r" giving "r" in the simulated omnibox. The results for
   // 'r' will be not cached because it is only 1 character long.
-  InMemoryURLIndex::String16Vector terms;
+  String16Vector original_terms;
   string16 term_r = ASCIIToUTF16("r");
-  terms.push_back(term_r);
-  url_index_->HistoryItemsForTerms(terms);
+  original_terms.push_back(term_r);
+  url_index_->HistoryItemsForTerms(original_terms);
   EXPECT_EQ(0U, cache.size());
 
   // Simulate typing "re" giving "r re" in the simulated omnibox.
   string16 term_re = ASCIIToUTF16("re");
-  terms.push_back(term_re);
+  original_terms.push_back(term_re);
   // 're' should be cached at this point but not 'r' as it is a single
   // character.
-  ASSERT_EQ(2U, terms.size());
-  url_index_->HistoryItemsForTerms(terms);
+  ASSERT_EQ(2U, original_terms.size());
+  url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(1U, cache.size());
   CheckTerm(cache, term_re);
 
   // Simulate typing "reco" giving "r re reco" in the simulated omnibox.
   string16 term_reco = ASCIIToUTF16("reco");
-  terms.push_back(term_reco);
+  original_terms.push_back(term_reco);
   // 're' and 'reco' should be cached at this point but not 'r' as it is a
   // single character.
-  url_index_->HistoryItemsForTerms(terms);
+  url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(2U, cache.size());
   CheckTerm(cache, term_re);
   CheckTerm(cache, term_reco);
 
-  terms.clear();  // Simulate pressing <ESC>.
+  original_terms.clear();  // Simulate pressing <ESC>.
 
   // Simulate typing "mort".
   string16 term_mort = ASCIIToUTF16("mort");
-  terms.push_back(term_mort);
+  original_terms.push_back(term_mort);
   // Since we now have only one search term, the cached results for 're' and
   // 'reco' should be purged, giving us only 1 item in the cache (for 'mort').
-  url_index_->HistoryItemsForTerms(terms);
+  url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(1U, cache.size());
   CheckTerm(cache, term_mort);
 
   // Simulate typing "reco" giving "mort reco" in the simulated omnibox.
-  terms.push_back(term_reco);
-  url_index_->HistoryItemsForTerms(terms);
+  original_terms.push_back(term_reco);
+  url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(2U, cache.size());
   CheckTerm(cache, term_mort);
   CheckTerm(cache, term_reco);
 
   // Simulate a <DELETE> by removing the 'reco' and adding back the 'rec'.
-  terms.resize(terms.size() - 1);
+  original_terms.resize(original_terms.size() - 1);
   string16 term_rec = ASCIIToUTF16("rec");
-  terms.push_back(term_rec);
-  url_index_->HistoryItemsForTerms(terms);
+  original_terms.push_back(term_rec);
+  url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(2U, cache.size());
   CheckTerm(cache, term_mort);
   CheckTerm(cache, term_rec);
@@ -552,14 +518,14 @@
 TEST_F(InMemoryURLIndexTest, AddNewRows) {
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
-  InMemoryURLIndex::String16Vector terms;
+  String16Vector original_terms;
 
   // Verify that the row we're going to add does not already exist.
   URLID new_row_id = 87654321;
   // Newly created URLRows get a last_visit time of 'right now' so it should
   // qualify as a quick result candidate.
-  terms.push_back(ASCIIToUTF16("brokeandalone"));
-  EXPECT_TRUE(url_index_->HistoryItemsForTerms(terms).empty());
+  original_terms.push_back(ASCIIToUTF16("brokeandalone"));
+  EXPECT_TRUE(url_index_->HistoryItemsForTerms(original_terms).empty());
 
   // Add a new row.
   URLRow new_row(GURL("http://www.brokeandaloneinmanitoba.com/"), new_row_id);
@@ -567,26 +533,27 @@
   url_index_->UpdateURL(new_row_id, new_row);
 
   // Verify that we can retrieve it.
-  EXPECT_EQ(1U, url_index_->HistoryItemsForTerms(terms).size());
+  EXPECT_EQ(1U, url_index_->HistoryItemsForTerms(original_terms).size());
 
   // Add it again just to be sure that is harmless.
   url_index_->UpdateURL(new_row_id, new_row);
-  EXPECT_EQ(1U, url_index_->HistoryItemsForTerms(terms).size());
+  EXPECT_EQ(1U, url_index_->HistoryItemsForTerms(original_terms).size());
 }
 
 TEST_F(InMemoryURLIndexTest, DeleteRows) {
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
-  InMemoryURLIndex::String16Vector terms;
+  String16Vector original_terms;
 
   // Make sure we actually get an existing result.
-  terms.push_back(ASCIIToUTF16("DrudgeReport"));
-  ScoredHistoryMatches matches = url_index_->HistoryItemsForTerms(terms);
+  original_terms.push_back(ASCIIToUTF16("DrudgeReport"));
+  ScoredHistoryMatches matches =
+      url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(1U, matches.size());
 
   // Determine the row id for that result, delete that id, then search again.
   url_index_->DeleteURL(matches[0].url_info.id());
-  EXPECT_TRUE(url_index_->HistoryItemsForTerms(terms).empty());
+  EXPECT_TRUE(url_index_->HistoryItemsForTerms(original_terms).empty());
 }
 
 TEST_F(InMemoryURLIndexTest, WhitelistedURLs) {
@@ -697,77 +664,64 @@
   url_index.SavePrivateData(&index_cache);
 
   // Capture our private data so we can later compare for equality.
-  int history_item_count(url_index.history_item_count_);
-  InMemoryURLIndex::String16Vector word_list(url_index.word_list_);
-  InMemoryURLIndex::WordMap word_map(url_index.word_map_);
-  InMemoryURLIndex::CharWordIDMap char_word_map(url_index.char_word_map_);
-  InMemoryURLIndex::WordIDHistoryMap word_id_history_map(
-      url_index.word_id_history_map_);
-  InMemoryURLIndex::HistoryInfoMap history_info_map(
-      url_index.history_info_map_);
+  URLIndexPrivateData& private_data(*(url_index_->private_data_));
+  String16Vector word_list(private_data.word_list_);
+  WordMap word_map(private_data.word_map_);
+  CharWordIDMap char_word_map(private_data.char_word_map_);
+  WordIDHistoryMap word_id_history_map(private_data.word_id_history_map_);
+  HistoryIDWordMap history_id_word_map(private_data.history_id_word_map_);
+  HistoryInfoMap history_info_map(private_data.history_info_map_);
 
   // Prove that there is really something there.
-  EXPECT_GT(url_index.history_item_count_, 0);
-  EXPECT_FALSE(url_index.word_list_.empty());
-  EXPECT_FALSE(url_index.word_map_.empty());
-  EXPECT_FALSE(url_index.char_word_map_.empty());
-  EXPECT_FALSE(url_index.word_id_history_map_.empty());
-  EXPECT_FALSE(url_index.history_info_map_.empty());
+  EXPECT_FALSE(private_data.word_list_.empty());
+  // available_words_ will already be empty since we have freshly built the
+  // data set for this test.
+  EXPECT_TRUE(private_data.available_words_.empty());
+  EXPECT_FALSE(private_data.word_map_.empty());
+  EXPECT_FALSE(private_data.char_word_map_.empty());
+  EXPECT_FALSE(private_data.word_id_history_map_.empty());
+  EXPECT_FALSE(private_data.history_id_word_map_.empty());
+  EXPECT_FALSE(private_data.history_info_map_.empty());
 
   // Clear and then prove it's clear.
   url_index.ClearPrivateData();
-  EXPECT_EQ(0, url_index.history_item_count_);
-  EXPECT_TRUE(url_index.word_list_.empty());
-  EXPECT_TRUE(url_index.word_map_.empty());
-  EXPECT_TRUE(url_index.char_word_map_.empty());
-  EXPECT_TRUE(url_index.word_id_history_map_.empty());
-  EXPECT_TRUE(url_index.history_info_map_.empty());
+  EXPECT_TRUE(private_data.word_list_.empty());
+  EXPECT_TRUE(private_data.available_words_.empty());
+  EXPECT_TRUE(private_data.word_map_.empty());
+  EXPECT_TRUE(private_data.char_word_map_.empty());
+  EXPECT_TRUE(private_data.word_id_history_map_.empty());
+  EXPECT_TRUE(private_data.history_id_word_map_.empty());
+  EXPECT_TRUE(private_data.history_info_map_.empty());
 
   // Restore the cache.
   EXPECT_TRUE(url_index.RestorePrivateData(index_cache));
 
   // Compare the restored and captured for equality.
-  EXPECT_EQ(history_item_count, url_index.history_item_count_);
-  EXPECT_EQ(word_list.size(), url_index.word_list_.size());
-  EXPECT_EQ(word_map.size(), url_index.word_map_.size());
-  EXPECT_EQ(char_word_map.size(), url_index.char_word_map_.size());
-  EXPECT_EQ(word_id_history_map.size(), url_index.word_id_history_map_.size());
-  EXPECT_EQ(history_info_map.size(), url_index.history_info_map_.size());
+  EXPECT_EQ(word_list.size(), private_data.word_list_.size());
+  EXPECT_EQ(word_map.size(), private_data.word_map_.size());
+  EXPECT_EQ(char_word_map.size(), private_data.char_word_map_.size());
+  EXPECT_EQ(word_id_history_map.size(),
+            private_data.word_id_history_map_.size());
+  EXPECT_EQ(history_id_word_map.size(),
+            private_data.history_id_word_map_.size());
+  EXPECT_EQ(history_info_map.size(), private_data.history_info_map_.size());
   // WordList must be index-by-index equal.
   size_t count = word_list.size();
   for (size_t i = 0; i < count; ++i)
-    EXPECT_EQ(word_list[i], url_index.word_list_[i]);
-  for (InMemoryURLIndex::CharWordIDMap::const_iterator expected =
-        char_word_map.begin(); expected != char_word_map.end(); ++expected) {
-    InMemoryURLIndex::CharWordIDMap::const_iterator actual =
-        url_index.char_word_map_.find(expected->first);
-    ASSERT_TRUE(url_index.char_word_map_.end() != actual);
-    const InMemoryURLIndex::WordIDSet& expected_set(expected->second);
-    const InMemoryURLIndex::WordIDSet& actual_set(actual->second);
-    ASSERT_EQ(expected_set.size(), actual_set.size());
-    for (InMemoryURLIndex::WordIDSet::const_iterator set_iter =
-        expected_set.begin(); set_iter != expected_set.end(); ++set_iter)
-      EXPECT_GT(actual_set.count(*set_iter), 0U);
-  }
-  for (InMemoryURLIndex::WordIDHistoryMap::const_iterator expected =
-      word_id_history_map.begin(); expected != word_id_history_map.end();
-      ++expected) {
-    InMemoryURLIndex::WordIDHistoryMap::const_iterator actual =
-        url_index.word_id_history_map_.find(expected->first);
-    ASSERT_TRUE(url_index.word_id_history_map_.end() != actual);
-    const InMemoryURLIndex::HistoryIDSet& expected_set(expected->second);
-    const InMemoryURLIndex::HistoryIDSet& actual_set(actual->second);
-    ASSERT_EQ(expected_set.size(), actual_set.size());
-    for (InMemoryURLIndex::HistoryIDSet::const_iterator set_iter =
-        expected_set.begin(); set_iter != expected_set.end(); ++set_iter)
-      EXPECT_GT(actual_set.count(*set_iter), 0U);
-  }
-  for (InMemoryURLIndex::HistoryInfoMap::const_iterator expected =
-      history_info_map.begin(); expected != history_info_map.end();
-      ++expected) {
-    InMemoryURLIndex::HistoryInfoMap::const_iterator actual =
-        url_index.history_info_map_.find(expected->first);
-    ASSERT_FALSE(url_index.history_info_map_.end() == actual);
+    EXPECT_EQ(word_list[i], private_data.word_list_[i]);
+
+  ExpectMapOfContainersIdentical(char_word_map,
+                                 private_data.char_word_map_);
+  ExpectMapOfContainersIdentical(word_id_history_map,
+                                 private_data.word_id_history_map_);
+  ExpectMapOfContainersIdentical(history_id_word_map,
+                                 private_data.history_id_word_map_);
+
+  for (HistoryInfoMap::const_iterator expected = history_info_map.begin();
+       expected != history_info_map.end(); ++expected) {
+    HistoryInfoMap::const_iterator actual =
+        private_data.history_info_map_.find(expected->first);
+    ASSERT_FALSE(private_data.history_info_map_.end() == actual);
     const URLRow& expected_row(expected->second);
     const URLRow& actual_row(actual->second);
     EXPECT_EQ(expected_row.visit_count(), actual_row.visit_count());