Send all field trials from the browser.

base/metrics/field_trial_unittest.cc

Index: base/metrics/field_trial_unittest.cc
diff --git a/base/metrics/field_trial_unittest.cc b/base/metrics/field_trial_unittest.cc
index ce95c2ae15b12e510a0abc47b0a6157dc94f1c60..ab71cbda588c095c25c72be1b611481909a58555 100644
--- a/base/metrics/field_trial_unittest.cc
+++ b/base/metrics/field_trial_unittest.cc
@@ -311,6 +311,36 @@ TEST_F(FieldTrialTest, ActiveGroups) {
   }
 }
 
+TEST_F(FieldTrialTest, AllGroups) {
+  FieldTrial::FieldTrialState field_trial_state;
+  std::string one_winner("One Winner");
+  scoped_refptr<FieldTrial> trial =
+      CreateFieldTrial(one_winner, 10, "Default", NULL);
+  std::string winner("Winner");
+  trial->AppendGroup(winner, 10);
+  EXPECT_TRUE(trial->GetState(&field_trial_state));
+  EXPECT_EQ(one_winner, field_trial_state.trial_name);
+  EXPECT_EQ(winner, field_trial_state.group_name);
+  trial->group();
+  EXPECT_TRUE(trial->GetState(&field_trial_state));
+  EXPECT_EQ(one_winner, field_trial_state.trial_name);
+  EXPECT_EQ(winner, field_trial_state.group_name);
+
+  std::string multi_group("MultiGroup");
+  scoped_refptr<FieldTrial> multi_group_trial =
+      CreateFieldTrial(multi_group, 9, "Default", NULL);
+
+  multi_group_trial->AppendGroup("Me", 3);
+  multi_group_trial->AppendGroup("You", 3);
+  multi_group_trial->AppendGroup("Them", 3);
+  EXPECT_TRUE(multi_group_trial->GetState(&field_trial_state));
+  // Finalize the group selection by accessing the selected group.
+  multi_group_trial->group();
+  EXPECT_TRUE(multi_group_trial->GetState(&field_trial_state));
+  EXPECT_EQ(multi_group, field_trial_state.trial_name);
+  EXPECT_EQ(multi_group_trial->group_name(), field_trial_state.group_name);
+}
+
 TEST_F(FieldTrialTest, ActiveGroupsNotFinalized) {
   const char kTrialName[] = "TestTrial";
   const char kSecondaryGroupName[] = "SecondaryGroup";
@@ -388,6 +418,44 @@ TEST_F(FieldTrialTest, Save) {
   EXPECT_EQ("Some name/Winner/xxx/yyyy/zzz/default/", save_string);
 }
 
+TEST_F(FieldTrialTest, SaveAll) {
+  std::string save_string;
+
+  scoped_refptr<FieldTrial> trial =
+      CreateFieldTrial("Some name", 10, "Default some name", NULL);
+  EXPECT_EQ("", trial->group_name_internal());
+  FieldTrialList::AllStatesToString(&save_string);
+  EXPECT_EQ("Some name/Default some name/", save_string);
+  save_string.clear();
+
+  // Create a winning group.
+  trial->AppendGroup("Winner", 10);
+  // Finalize the group selection by accessing the selected group.
+  trial->group();
+  FieldTrialList::AllStatesToString(&save_string);
+  EXPECT_EQ("*Some name/Winner/", save_string);
+  save_string.clear();
+
+  // Create a second trial and winning group.
+  scoped_refptr<FieldTrial> trial2 =
+      CreateFieldTrial("xxx", 10, "Default xxx", NULL);
+  trial2->AppendGroup("yyyy", 10);
+  // Finalize the group selection by accessing the selected group.
+  trial2->group();
+
+  FieldTrialList::AllStatesToString(&save_string);
+  // We assume names are alphabetized... though this is not critical.
+  EXPECT_EQ("*Some name/Winner/*xxx/yyyy/", save_string);
+  save_string.clear();
+
+  // Create a third trial with only the default group.
+  scoped_refptr<FieldTrial> trial3 =
+      CreateFieldTrial("zzz", 10, "default", NULL);
+
+  FieldTrialList::AllStatesToString(&save_string);
+  EXPECT_EQ("*Some name/Winner/*xxx/yyyy/zzz/default/", save_string);

[Alexei Svitkine (slow), 2014/11/10 19:28:47]

Could you also add a test that de-serializing the string results in the expected
trials being enabled/disabled? For that, you can re-create a new FieldTrialList.

[Georges Khalil, 2014/11/10 20:50:34]

Already exists from a previous CL that landed, test is called
CreateTrialsFromStringForceActivation.

[Alexei Svitkine (slow), 2014/11/10 20:52:35]

That doesn't test that the two formats match though. If you change the format of
AllStatesToString() output and update this test, then the
CreateTrialsFromStringForceActivation test won't break even though that function
now won't be able to parse the output of AllStatesToString().

[Georges Khalil, 2014/11/10 22:36:10]

New test added (StatesStringFormat).

+}
+
 TEST_F(FieldTrialTest, Restore) {
   ASSERT_FALSE(FieldTrialList::TrialExists("Some_name"));
   ASSERT_FALSE(FieldTrialList::TrialExists("xxx"));