Improve Autocomplete Matches and Handling of Large Results Sets

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 110946)
+++ chrome/browser/history/in_memory_url_index_unittest.cc	(working copy)
@@ -10,6 +10,7 @@
 #include "base/string16.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
+#include "chrome/browser/autocomplete/autocomplete.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"
@@ -194,26 +195,6 @@
   return FILE_PATH_LITERAL("url_history_provider_test_limited.db.txt");
 }
 
-class ExpandedInMemoryURLIndexTest : public InMemoryURLIndexTest {
- protected:
-  virtual void SetUp();
-};
-
-void ExpandedInMemoryURLIndexTest::SetUp() {
-  InMemoryURLIndexTest::SetUp();
-  // Add 600 more history items.
-  // NOTE: Keep the string length constant at least the length of the format
-  // string plus 5 to account for a 3 digit number and terminator.
-  char url_format[] = "http://www.google.com/%d";
-  const size_t kMaxLen = arraysize(url_format) + 5;
-  char url_string[kMaxLen + 1];
-  for (int i = 0; i < 600; ++i) {
-    base::snprintf(url_string, kMaxLen, url_format, i);
-    URLRow row(MakeURLRow(url_string, "Google Search", 20, 0, 20));
-    AddURL(row);
-  }
-}
-
 TEST_F(InMemoryURLIndexTest, Construction) {
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   EXPECT_TRUE(url_index_.get());
@@ -244,7 +225,7 @@
 
   // See if a very specific term gives a single result.
   ScoredHistoryMatches matches =
-      url_index_->HistoryItemsForTerms(Make1Term("DrudgeReport"));
+      url_index_->HistoryItemsForTerms(ASCIIToUTF16("DrudgeReport"));
   ASSERT_EQ(1U, matches.size());
 
   // Verify that we got back the result we expected.
@@ -253,14 +234,14 @@
   EXPECT_EQ(ASCIIToUTF16("DRUDGE REPORT 2010"), matches[0].url_info.title());
 
   // Search which should result in multiple results.
-  matches = url_index_->HistoryItemsForTerms(Make1Term("drudge"));
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("drudge"));
   ASSERT_EQ(2U, matches.size());
   // The results should be in descending score order.
   EXPECT_GE(matches[0].raw_score, matches[1].raw_score);
 
   // Search which should result in nearly perfect result.
-  matches = url_index_->HistoryItemsForTerms(Make2Terms("https",
-                                                        "NearlyPerfectResult"));
+  matches = url_index_->HistoryItemsForTerms(
+      ASCIIToUTF16("https NearlyPerfectResult"));
   ASSERT_EQ(1U, matches.size());
   // The results should have a very high score.
   EXPECT_GT(matches[0].raw_score, 900);
@@ -271,11 +252,7 @@
             matches[0].url_info.title());
 
   // Search which should result in very poor result.
-  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);
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("z y x"));
   ASSERT_EQ(1U, matches.size());
   // The results should have a poor score.
   EXPECT_LT(matches[0].raw_score, 500);
@@ -286,22 +263,46 @@
             matches[0].url_info.title());
 
   // Search which will match at the end of an URL with encoded characters.
-  matches = url_index_->HistoryItemsForTerms(Make1Term("ice"));
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("ice"));
   ASSERT_EQ(1U, matches.size());
 }
 
-TEST_F(ExpandedInMemoryURLIndexTest, ShortCircuit) {
+TEST_F(InMemoryURLIndexTest, ProperStringMatching) {
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
 
-  // A search for 'w' should short-circuit and not return any matches.
+  // Search for the following with the expected results:
+  // "atdmt view" - found
+  // "atdmt.view" - not found
+  // "view.atdmt" - found
   ScoredHistoryMatches matches =
-      url_index_->HistoryItemsForTerms(Make1Term("w"));
-  EXPECT_TRUE(matches.empty());
+      url_index_->HistoryItemsForTerms(ASCIIToUTF16("atdmt view"));
+  ASSERT_EQ(1U, matches.size());
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("atdmt.view"));
+  ASSERT_EQ(0U, matches.size());
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("view.atdmt"));
+  ASSERT_EQ(1U, matches.size());
+}
 
-  // A search for 'working' should not short-circuit.
-  matches = url_index_->HistoryItemsForTerms(Make1Term("working"));
-  EXPECT_EQ(1U, matches.size());
+TEST_F(InMemoryURLIndexTest, HugeResultSet) {
+  url_index_.reset(new InMemoryURLIndex(FilePath()));
+  url_index_->Init(this, "en,ja,hi,zh");
+
+  // Create a huge set of qualifying history items.
+  for (URLID row_id = 5000; row_id < 6000; ++row_id) {
+    URLRow new_row(GURL("http://www.brokeandaloneinmanitoba.com/"), row_id);
+    new_row.set_last_visit(base::Time::Now());
+    url_index_->UpdateURL(row_id, new_row);
+  }
+
+  ScoredHistoryMatches matches =
+      url_index_->HistoryItemsForTerms(ASCIIToUTF16("b"));
+  ASSERT_EQ(AutocompleteProvider::kMaxMatches, matches.size());
+  // There are 7 matches already in the database.
+  ASSERT_EQ(1007U, url_index_->pre_filter_item_count);
+  ASSERT_EQ(500U, url_index_->post_filter_item_count);
+  ASSERT_EQ(AutocompleteProvider::kMaxMatches,
+            url_index_->post_scoring_item_count);
 }
 
 TEST_F(InMemoryURLIndexTest, TitleSearch) {
@@ -309,14 +310,10 @@
   url_index_->Init(this, "en,ja,hi,zh");
   // Signal if someone has changed the test DB.
   EXPECT_EQ(27U, url_index_->private_data_->history_info_map_.size());
-  String16Vector original_terms;
 
   // Ensure title is being searched.
-  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);
+      url_index_->HistoryItemsForTerms(ASCIIToUTF16("MORTGAGE RATE DROPS"));
   ASSERT_EQ(1U, matches.size());
 
   // Verify that we got back the result we expected.
@@ -333,12 +330,8 @@
   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"));
+  string16 original_terms =
+      ASCIIToUTF16("lebronomics could high taxes influence");
   ScoredHistoryMatches matches =
       url_index_->HistoryItemsForTerms(original_terms);
   ASSERT_EQ(1U, matches.size());
@@ -354,13 +347,7 @@
   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"));
+  string16 new_terms = ASCIIToUTF16("does eat oats little lambs ivy");
   matches = url_index_->HistoryItemsForTerms(new_terms);
   ASSERT_EQ(0U, matches.size());
 
@@ -383,25 +370,25 @@
   // The presence of duplicate characters should succeed. Exercise by cycling
   // through a string with several duplicate characters.
   ScoredHistoryMatches matches =
-      url_index_->HistoryItemsForTerms(Make1Term("ABRA"));
+      url_index_->HistoryItemsForTerms(ASCIIToUTF16("ABRA"));
   ASSERT_EQ(1U, matches.size());
   EXPECT_EQ(28, matches[0].url_info.id());
   EXPECT_EQ("http://www.ddj.com/windows/184416623",
             matches[0].url_info.url().spec());
 
-  matches = url_index_->HistoryItemsForTerms(Make1Term("ABRACAD"));
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("ABRACAD"));
   ASSERT_EQ(1U, matches.size());
   EXPECT_EQ(28, matches[0].url_info.id());
 
-  matches = url_index_->HistoryItemsForTerms(Make1Term("ABRACADABRA"));
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("ABRACADABRA"));
   ASSERT_EQ(1U, matches.size());
   EXPECT_EQ(28, matches[0].url_info.id());
 
-  matches = url_index_->HistoryItemsForTerms(Make1Term("ABRACADABR"));
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("ABRACADABR"));
   ASSERT_EQ(1U, matches.size());
   EXPECT_EQ(28, matches[0].url_info.id());
 
-  matches = url_index_->HistoryItemsForTerms(Make1Term("ABRACA"));
+  matches = url_index_->HistoryItemsForTerms(ASCIIToUTF16("ABRACA"));
   ASSERT_EQ(1U, matches.size());
   EXPECT_EQ(28, matches[0].url_info.id());
 }
@@ -424,60 +411,44 @@
   // Now simulate typing search terms into the omnibox and check the state of
   // the cache as each item is 'typed'.
 
-  // Simulate typing "r" giving "r" in the simulated omnibox. The results for
+  // Simulate typing "r" giving "r" in the simulated omnibox.  The results for
   // 'r' will be not cached because it is only 1 character long.
-  String16Vector original_terms;
-  string16 term_r = ASCIIToUTF16("r");
-  original_terms.push_back(term_r);
-  url_index_->HistoryItemsForTerms(original_terms);
+  url_index_->HistoryItemsForTerms(ASCIIToUTF16("r"));
   EXPECT_EQ(0U, cache.size());
 
   // Simulate typing "re" giving "r re" in the simulated omnibox.
-  string16 term_re = ASCIIToUTF16("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, original_terms.size());
-  url_index_->HistoryItemsForTerms(original_terms);
+  url_index_->HistoryItemsForTerms(ASCIIToUTF16("r re"));
   ASSERT_EQ(1U, cache.size());
-  CheckTerm(cache, term_re);
+  CheckTerm(cache, ASCIIToUTF16("re"));
 
   // Simulate typing "reco" giving "r re reco" in the simulated omnibox.
-  string16 term_reco = ASCIIToUTF16("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(original_terms);
+  url_index_->HistoryItemsForTerms(ASCIIToUTF16("r re reco"));
   ASSERT_EQ(2U, cache.size());
-  CheckTerm(cache, term_re);
-  CheckTerm(cache, term_reco);
+  CheckTerm(cache, ASCIIToUTF16("re"));
+  CheckTerm(cache, ASCIIToUTF16("reco"));
 
-  original_terms.clear();  // Simulate pressing <ESC>.
-
   // Simulate typing "mort".
-  string16 term_mort = ASCIIToUTF16("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(original_terms);
+  url_index_->HistoryItemsForTerms(ASCIIToUTF16("mort"));
   ASSERT_EQ(1U, cache.size());
-  CheckTerm(cache, term_mort);
+  CheckTerm(cache, ASCIIToUTF16("mort"));
 
   // Simulate typing "reco" giving "mort reco" in the simulated omnibox.
-  original_terms.push_back(term_reco);
-  url_index_->HistoryItemsForTerms(original_terms);
+  url_index_->HistoryItemsForTerms(ASCIIToUTF16("mort reco"));
   ASSERT_EQ(2U, cache.size());
-  CheckTerm(cache, term_mort);
-  CheckTerm(cache, term_reco);
+  CheckTerm(cache, ASCIIToUTF16("mort"));
+  CheckTerm(cache, ASCIIToUTF16("reco"));
 
   // Simulate a <DELETE> by removing the 'reco' and adding back the 'rec'.
-  original_terms.resize(original_terms.size() - 1);
-  string16 term_rec = ASCIIToUTF16("rec");
-  original_terms.push_back(term_rec);
-  url_index_->HistoryItemsForTerms(original_terms);
+  url_index_->HistoryItemsForTerms(ASCIIToUTF16("mort rec"));
   ASSERT_EQ(2U, cache.size());
-  CheckTerm(cache, term_mort);
-  CheckTerm(cache, term_rec);
+  CheckTerm(cache, ASCIIToUTF16("mort"));
+  CheckTerm(cache, ASCIIToUTF16("rec"));
 }
 
 TEST_F(InMemoryURLIndexTest, Scoring) {
@@ -518,14 +489,13 @@
 TEST_F(InMemoryURLIndexTest, AddNewRows) {
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
-  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.
-  original_terms.push_back(ASCIIToUTF16("brokeandalone"));
-  EXPECT_TRUE(url_index_->HistoryItemsForTerms(original_terms).empty());
+  EXPECT_TRUE(url_index_->HistoryItemsForTerms(
+      ASCIIToUTF16("brokeandalone")).empty());
 
   // Add a new row.
   URLRow new_row(GURL("http://www.brokeandaloneinmanitoba.com/"), new_row_id);
@@ -533,27 +503,28 @@
   url_index_->UpdateURL(new_row_id, new_row);
 
   // Verify that we can retrieve it.
-  EXPECT_EQ(1U, url_index_->HistoryItemsForTerms(original_terms).size());
+  EXPECT_EQ(1U, url_index_->HistoryItemsForTerms(
+      ASCIIToUTF16("brokeandalone")).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(original_terms).size());
+  EXPECT_EQ(1U, url_index_->HistoryItemsForTerms(
+      ASCIIToUTF16("brokeandalone")).size());
 }
 
 TEST_F(InMemoryURLIndexTest, DeleteRows) {
   url_index_.reset(new InMemoryURLIndex(FilePath()));
   url_index_->Init(this, "en,ja,hi,zh");
-  String16Vector original_terms;
 
   // Make sure we actually get an existing result.
-  original_terms.push_back(ASCIIToUTF16("DrudgeReport"));
   ScoredHistoryMatches matches =
-      url_index_->HistoryItemsForTerms(original_terms);
+      url_index_->HistoryItemsForTerms(ASCIIToUTF16("DrudgeReport"));
   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(original_terms).empty());
+  EXPECT_TRUE(url_index_->HistoryItemsForTerms(
+      ASCIIToUTF16("DrudgeReport")).empty());
 }
 
 TEST_F(InMemoryURLIndexTest, WhitelistedURLs) {