Password reuse look-up optimization

components/password_manager/core/browser/password_reuse_detector_unittest.cc

Index: components/password_manager/core/browser/password_reuse_detector_unittest.cc
diff --git a/components/password_manager/core/browser/password_reuse_detector_unittest.cc b/components/password_manager/core/browser/password_reuse_detector_unittest.cc
index 7e8331ec440166a8a01c05612861cd199e789671..dac4dd694cb000f0dc3ec6b6e3486778c3bbc81a 100644
--- a/components/password_manager/core/browser/password_reuse_detector_unittest.cc
+++ b/components/password_manager/core/browser/password_reuse_detector_unittest.cc
@@ -22,21 +22,30 @@ namespace password_manager {
 
 namespace {
 
-std::vector<std::unique_ptr<PasswordForm>> GetSavedForms() {
-  std::vector<std::unique_ptr<PasswordForm>> result;
-  std::vector<std::pair<std::string, std::string>> domains_passwords = {
+std::vector<std::pair<std::string, std::string>> GetTestDomainsPasswords() {
+  return {
       {"https://accounts.google.com", "password"},
       {"https://facebook.com", "123456789"},
       {"https://a.appspot.com", "abcdefghi"},
       {"https://twitter.com", "short"},
+      {"https://example1.com", "secretword"},
+      {"https://example2.com", "secretword"},
   };
+}
 
-  for (const auto& domain_password : domains_passwords) {
-    std::unique_ptr<PasswordForm> form(new PasswordForm);
-    form->signon_realm = domain_password.first;
-    form->password_value = ASCIIToUTF16(domain_password.second);
-    result.push_back(std::move(form));
-  }
+std::unique_ptr<PasswordForm> GetForm(
+    const std::pair<std::string, std::string>& domain_password) {
+  std::unique_ptr<PasswordForm> form(new PasswordForm);
+  form->signon_realm = domain_password.first;
+  form->password_value = ASCIIToUTF16(domain_password.second);
+  return form;
+}
+
+std::vector<std::unique_ptr<PasswordForm>> GetForms(
+    const std::vector<std::pair<std::string, std::string>>& domains_passwords) {
+  std::vector<std::unique_ptr<PasswordForm>> result;
+  for (const auto& domain_password : domains_passwords)
+    result.push_back(GetForm(domain_password));
   return result;
 }
 
@@ -52,7 +61,7 @@ PasswordStoreChangeList GetChangeList(
 
 TEST(PasswordReuseDetectorTest, TypingPasswordOnDifferentSite) {
   PasswordReuseDetector reuse_detector;
-  reuse_detector.OnGetPasswordStoreResults(GetSavedForms());
+  reuse_detector.OnGetPasswordStoreResults(GetForms(GetTestDomainsPasswords()));
   MockPasswordReuseDetectorConsumer mockConsumer;
 
   EXPECT_CALL(mockConsumer, OnReuseFound(_, _, _, _)).Times(0);
@@ -63,14 +72,27 @@ TEST(PasswordReuseDetectorTest, TypingPasswordOnDifferentSite) {
   testing::Mock::VerifyAndClearExpectations(&mockConsumer);
 
   EXPECT_CALL(mockConsumer,
-              OnReuseFound(ASCIIToUTF16("password"), "google.com", 3, 1));
+              OnReuseFound(ASCIIToUTF16("password"), "google.com", 5, 1));
   reuse_detector.CheckReuse(ASCIIToUTF16("123password"), "https://evil.com",
                             &mockConsumer);
+  testing::Mock::VerifyAndClearExpectations(&mockConsumer);
+
+  EXPECT_CALL(mockConsumer,
+              OnReuseFound(ASCIIToUTF16("password"), "google.com", 5, 1));
+  reuse_detector.CheckReuse(ASCIIToUTF16("password"), "https://evil.com",
+                            &mockConsumer);
+
+  testing::Mock::VerifyAndClearExpectations(&mockConsumer);
+
+  EXPECT_CALL(mockConsumer,
+              OnReuseFound(ASCIIToUTF16("secretword"), "example1.com", 5, 2));
+  reuse_detector.CheckReuse(ASCIIToUTF16("abcdsecretword"), "https://evil.com",
+                            &mockConsumer);
 }
 
 TEST(PasswordReuseDetectorTest, PSLMatchNoReuseEvent) {
   PasswordReuseDetector reuse_detector;
-  reuse_detector.OnGetPasswordStoreResults(GetSavedForms());
+  reuse_detector.OnGetPasswordStoreResults(GetForms(GetTestDomainsPasswords()));
   MockPasswordReuseDetectorConsumer mockConsumer;
 
   EXPECT_CALL(mockConsumer, OnReuseFound(_, _, _, _)).Times(0);
@@ -80,20 +102,20 @@ TEST(PasswordReuseDetectorTest, PSLMatchNoReuseEvent) {
 
 TEST(PasswordReuseDetectorTest, NoPSLMatchReuseEvent) {
   PasswordReuseDetector reuse_detector;
-  reuse_detector.OnGetPasswordStoreResults(GetSavedForms());
+  reuse_detector.OnGetPasswordStoreResults(GetForms(GetTestDomainsPasswords()));
   MockPasswordReuseDetectorConsumer mockConsumer;
 
   // a.appspot.com and b.appspot.com are not PSL matches. So reuse event should
   // be raised.
   EXPECT_CALL(mockConsumer,
-              OnReuseFound(ASCIIToUTF16("abcdefghi"), "a.appspot.com", 3, 1));
+              OnReuseFound(ASCIIToUTF16("abcdefghi"), "a.appspot.com", 5, 1));
   reuse_detector.CheckReuse(ASCIIToUTF16("abcdefghi"), "https://b.appspot.com",
                             &mockConsumer);
 }
 
 TEST(PasswordReuseDetectorTest, TooShortPasswordNoReuseEvent) {
   PasswordReuseDetector reuse_detector;
-  reuse_detector.OnGetPasswordStoreResults(GetSavedForms());
+  reuse_detector.OnGetPasswordStoreResults(GetForms(GetTestDomainsPasswords()));
   MockPasswordReuseDetectorConsumer mockConsumer;
 
   EXPECT_CALL(mockConsumer, OnReuseFound(_, _, _, _)).Times(0);
@@ -102,7 +124,7 @@ TEST(PasswordReuseDetectorTest, TooShortPasswordNoReuseEvent) {
 
 TEST(PasswordReuseDetectorTest, PasswordNotInputSuffixNoReuseEvent) {
   PasswordReuseDetector reuse_detector;
-  reuse_detector.OnGetPasswordStoreResults(GetSavedForms());
+  reuse_detector.OnGetPasswordStoreResults(GetForms(GetTestDomainsPasswords()));
   MockPasswordReuseDetectorConsumer mockConsumer;
 
   EXPECT_CALL(mockConsumer, OnReuseFound(_, _, _, _)).Times(0);
@@ -117,7 +139,8 @@ TEST(PasswordReuseDetectorTest, OnLoginsChanged) {
        {PasswordStoreChange::ADD, PasswordStoreChange::UPDATE,
         PasswordStoreChange::REMOVE}) {
     PasswordReuseDetector reuse_detector;
-    PasswordStoreChangeList changes = GetChangeList(type, GetSavedForms());
+    PasswordStoreChangeList changes =
+        GetChangeList(type, GetForms(GetTestDomainsPasswords()));
     reuse_detector.OnLoginsChanged(changes);
     MockPasswordReuseDetectorConsumer mockConsumer;
 
@@ -125,13 +148,42 @@ TEST(PasswordReuseDetectorTest, OnLoginsChanged) {
       EXPECT_CALL(mockConsumer, OnReuseFound(_, _, _, _)).Times(0);
     } else {
       EXPECT_CALL(mockConsumer,
-                  OnReuseFound(ASCIIToUTF16("password"), "google.com", 3, 1));
+                  OnReuseFound(ASCIIToUTF16("password"), "google.com", 5, 1));
     }
     reuse_detector.CheckReuse(ASCIIToUTF16("123password"), "https://evil.com",
                               &mockConsumer);
   }
 }
 
+TEST(PasswordReuseDetectorTest, CheckLongestPasswordMatchReturn) {
+  const std::vector<std::pair<std::string, std::string>> domain_passwords = {
+      {"https://example1.com", "234567890"},
+      {"https://example2.com", "01234567890"},
+      {"https://example3.com", "1234567890"},
+  };
+
+  PasswordReuseDetector reuse_detector;
+  reuse_detector.OnGetPasswordStoreResults(GetForms(domain_passwords));
+
+  MockPasswordReuseDetectorConsumer mockConsumer;
+
+  EXPECT_CALL(mockConsumer,
+              OnReuseFound(ASCIIToUTF16("01234567890"), "example2.com", 3, 1));
+  reuse_detector.CheckReuse(ASCIIToUTF16("abcd01234567890"), "https://evil.com",
+                            &mockConsumer);
+  testing::Mock::VerifyAndClearExpectations(&mockConsumer);
+
+  EXPECT_CALL(mockConsumer,
+              OnReuseFound(ASCIIToUTF16("1234567890"), "example3.com", 3, 1));
+  reuse_detector.CheckReuse(ASCIIToUTF16("1234567890"), "https://evil.com",
+                            &mockConsumer);
+  testing::Mock::VerifyAndClearExpectations(&mockConsumer);
+
+  EXPECT_CALL(mockConsumer, OnReuseFound(_, _, _, _)).Times(0);
+  reuse_detector.CheckReuse(ASCIIToUTF16("34567890"), "https://evil.com",
+                            &mockConsumer);
+}
+
 }  // namespace
 
 }  // namespace password_manager