Remove modality of MULTI_VALUE choice types in AboutFlags
Previously the UI for multivalues in AboutFlags was confusing, since
you could "enable" or "disable" the feature, then select an option
from a combobox. This change removes this modality, and instead, the
first option from the multivalue should be considered the "disabled"
version of the lab (we even assert that it has no command line flags).
This CL was originally http://codereview.chromium.org/6410082/ , but
cbentzel suggested we split it up into two CLs: this is the first of
them.
BUG=none
TEST=AboutFlagsTest.MultiValues
Review URL: http://codereview.chromium.org/6413037
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@74277 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index e755ee9..6755aa2 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -62,9 +62,10 @@
// distinct types of experiments:
// . SINGLE_VALUE: experiment is either on or off. Use the SINGLE_VALUE_TYPE
// macro for this type supplying the command line to the macro.
-// . MULTI_VALUE: if enabled the command line of the selected choice is enabled.
-// To specify this type of experiment use the macro MULTI_VALUE_TYPE supplying
-// it the array of choices.
+// . MULTI_VALUE: a list of choices, the first of which should correspond to a
+// deactivated state for this lab (i.e. no command line option). To specify
+// this type of experiment use the macro MULTI_VALUE_TYPE supplying it the
+// array of choices.
// See the documentation of Experiment for details on the fields.
//
// When adding a new choice, add it to the end of the list.
@@ -334,13 +335,35 @@
}
}
+// Confirms that an experiment is valid, used in a DCHECK in
+// SanitizeList below.
+bool ValidateExperiment(const Experiment& e) {
+ switch (e.type) {
+ case Experiment::SINGLE_VALUE:
+ DCHECK_EQ(0, e.num_choices);
+ DCHECK(!e.choices);
+ break;
+ case Experiment::MULTI_VALUE:
+ DCHECK_GT(e.num_choices, 0);
+ DCHECK(e.choices);
+ DCHECK(e.choices[0].command_line);
+ DCHECK_EQ('\0', e.choices[0].command_line[0]);
+ break;
+ default:
+ NOTREACHED();
+ }
+ return true;
+}
+
// Removes all experiments from prefs::kEnabledLabsExperiments that are
// unknown, to prevent this list to become very long as experiments are added
// and removed.
void SanitizeList(PrefService* prefs) {
std::set<std::string> known_experiments;
- for (size_t i = 0; i < num_experiments; ++i)
+ for (size_t i = 0; i < num_experiments; ++i) {
+ DCHECK(ValidateExperiment(experiments[i]));
AddInternalName(experiments[i], &known_experiments);
+ }
std::set<std::string> enabled_experiments;
GetEnabledFlags(prefs, &enabled_experiments);
@@ -386,10 +409,8 @@
}
// Returns the Value representing the choice data in the specified experiment.
-// If one of the choices is enabled |is_one_selected| is set to true.
Value* CreateChoiceData(const Experiment& experiment,
- const std::set<std::string>& enabled_experiments,
- bool* is_one_selected) {
+ const std::set<std::string>& enabled_experiments) {
DCHECK(experiment.type == Experiment::MULTI_VALUE);
ListValue* result = new ListValue;
for (int i = 0; i < experiment.num_choices; ++i) {
@@ -399,10 +420,7 @@
value->SetString("description",
l10n_util::GetStringUTF16(choice.description_id));
value->SetString("internal_name", name);
- bool is_selected = enabled_experiments.count(name) > 0;
- if (is_selected)
- *is_one_selected = true;
- value->SetBoolean("selected", is_selected);
+ value->SetBoolean("selected", enabled_experiments.count(name) > 0);
result->Append(value);
}
return result;
@@ -434,14 +452,19 @@
l10n_util::GetStringUTF16(
experiment.visible_description_id));
- bool enabled = enabled_experiments.count(experiment.internal_name) > 0;
-
- if (experiment.type == Experiment::MULTI_VALUE) {
- data->Set("choices", CreateChoiceData(experiment, enabled_experiments,
- &enabled));
+ switch (experiment.type) {
+ case Experiment::SINGLE_VALUE:
+ data->SetBoolean(
+ "enabled",
+ enabled_experiments.count(experiment.internal_name) > 0);
+ break;
+ case Experiment::MULTI_VALUE:
+ data->Set("choices", CreateChoiceData(experiment, enabled_experiments));
+ break;
+ default:
+ NOTREACHED();
}
- data->SetBoolean("enabled", enabled);
experiments_data->Append(data);
}
return experiments_data;
@@ -551,13 +574,16 @@
// We're being asked to enable a multi-choice experiment. Disable the
// currently selected choice.
DCHECK_NE(at_index, 0u);
- SetExperimentEnabled(prefs, internal_name.substr(0, at_index), false);
+ const std::string experiment_name = internal_name.substr(0, at_index);
+ SetExperimentEnabled(prefs, experiment_name, false);
- // And enable the new choice.
- std::set<std::string> enabled_experiments;
- GetSanitizedEnabledFlags(prefs, &enabled_experiments);
- enabled_experiments.insert(internal_name);
- SetEnabledFlags(prefs, enabled_experiments);
+ // And enable the new choice, if it is not the default first choice.
+ if (internal_name != experiment_name + "@0") {
+ std::set<std::string> enabled_experiments;
+ GetSanitizedEnabledFlags(prefs, &enabled_experiments);
+ enabled_experiments.insert(internal_name);
+ SetEnabledFlags(prefs, enabled_experiments);
+ }
return;
}
