[Chromecast] Use base::FeatureList to control features.

chromecast/browser/test/cast_features_browsertest.cc

Index: chromecast/browser/test/cast_features_browsertest.cc
diff --git a/chromecast/browser/test/cast_features_browsertest.cc b/chromecast/browser/test/cast_features_browsertest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..6093b96a7c92d91d8e201d6dccdf40d5e60f7e53
--- /dev/null
+++ b/chromecast/browser/test/cast_features_browsertest.cc
@@ -0,0 +1,174 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chromecast/base/cast_features.h"
+
+#include "base/feature_list.h"
+#include "base/macros.h"
+#include "base/metrics/field_trial_params.h"
+#include "chromecast/base/pref_names.h"
+#include "chromecast/browser/cast_browser_process.h"
+#include "chromecast/browser/test/cast_browser_test.h"
+#include "components/prefs/pref_service.h"
+
+namespace chromecast {
+namespace shell {
+namespace {
+
+const base::Feature kEnableFoo("enable_foo", base::FEATURE_DISABLED_BY_DEFAULT);
+const base::Feature kEnableBar("enable_bar", base::FEATURE_ENABLED_BY_DEFAULT);
+const base::Feature kEnableBaz("enable_baz", base::FEATURE_DISABLED_BY_DEFAULT);
+const base::Feature kEnableBat("enable_bat", base::FEATURE_ENABLED_BY_DEFAULT);
+
+const base::Feature kEnableParams("enable_params",
+                                  base::FEATURE_DISABLED_BY_DEFAULT);
+
+}  // namespace
+
+class CastFeaturesBrowserTest : public CastBrowserTest {
+ public:
+  CastFeaturesBrowserTest() {}
+  ~CastFeaturesBrowserTest() override {}
+
+  // Write |dcs_features| to the pref store. This method is intended to be
+  // overridden in internal test to utilize the real production codepath for
+  // setting features from the server.
+  virtual void SetFeatures(const base::DictionaryValue& dcs_features) {
+    auto pref_features = GetOverriddenFeaturesForStorage(dcs_features);
+    CastBrowserProcess::GetInstance()->pref_service()->Set(
+        prefs::kLatestDCSFeatures, pref_features);
+  }
+
+  static void ClearFeaturesInPrefs() {
+    DCHECK(CastBrowserProcess::GetInstance());
+    DCHECK(CastBrowserProcess::GetInstance()->pref_service());
+    CastBrowserProcess::GetInstance()->pref_service()->Set(
+        prefs::kLatestDCSFeatures, base::DictionaryValue());
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CastFeaturesBrowserTest);
+};
+
+IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, EmptyTest) {
+  // Default values should be returned.
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableFoo));
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableBar));
+}
+
+// Test that set features activate on the next boot. Part 1 of 2.
+IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
+                       PRE_TestFeaturesActivateOnBoot) {
+  // Default values should be returned.
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableFoo));
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableBar));
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableBaz));
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableBat));
+
+  // Set the features to be used on next boot.
+  base::DictionaryValue features;
+  features.SetBoolean("enable_foo", true);
+  features.SetBoolean("enable_bat", false);
+  SetFeatures(features);
+
+  // Default values should still be returned until next boot.
+  EXPECT_FALSE(base::FeatureList::IsEnabled(kEnableFoo));
+  EXPECT_TRUE(base::FeatureList::IsEnabled(kEnableBar));
+  EXPECT_FALSE(base::FeatureList::IsEnabled(kEnableBaz));
+  EXPECT_TRUE(base::FeatureList::IsEnabled(kEnableBat));
+}
+
+// Test that features activate on the next boot. Part 2 of 2.
+IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, TestFeaturesActivateOnBoot) {
+  // Overriden values set in test case above should be set.
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableFoo));
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableBar));
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableBaz));
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableBat));
+
+  // Clear the features for other tests.
+  ClearFeaturesInPrefs();
+}
+
+// Test that features with params activate on boot. Part 1 of 2.
+IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, PRE_TestParamsActivateOnBoot) {
+  // Default value should be returned.
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableParams));
+
+  // Set the features to be used on next boot.
+  base::DictionaryValue features;
+  auto params = base::MakeUnique<base::DictionaryValue>();
+  params->SetBoolean("bool_param", true);
+  params->SetBoolean("bool_param_2", false);
+  params->SetString("str_param", "foo");
+  params->SetDouble("doub_param", 3.14159);
+  params->SetInteger("int_param", 76543);
+  features.Set("enable_params", std::move(params));
+  SetFeatures(features);
+
+  // Default value should still be returned until next boot.
+  EXPECT_FALSE(base::FeatureList::IsEnabled(kEnableParams));
+}
+
+// Test that features with params activate on boot. Part 2 of 2.
+IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, TestParamsActivateOnBoot) {
+  // Check that the feature is now enabled.
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableParams));
+
+  // Check that the params are populated and correct.
+  ASSERT_TRUE(base::GetFieldTrialParamByFeatureAsBool(
+      kEnableParams, "bool_param", false /* default_value */));
+  ASSERT_FALSE(base::GetFieldTrialParamByFeatureAsBool(
+      kEnableParams, "bool_param_2", true /* default_value */));
+  ASSERT_EQ("foo",
+            base::GetFieldTrialParamValueByFeature(kEnableParams, "str_param"));
+  ASSERT_EQ(76543, base::GetFieldTrialParamByFeatureAsInt(
+                       kEnableParams, "int_param", 0 /* default_value */));
+  ASSERT_EQ(3.14159, base::GetFieldTrialParamByFeatureAsDouble(
+                         kEnableParams, "doub_param", 0.0 /* default_value */));
+
+  // Check that no extra parameters are set.
+  std::map<std::string, std::string> params_out;
+  ASSERT_TRUE(base::GetFieldTrialParamsByFeature(kEnableParams, &params_out));
+  ASSERT_EQ(5u, params_out.size());
+
+  // Clear the features for other tests.
+  ClearFeaturesInPrefs();
+}
+
+// Test that only well-formed features are persisted to disk. Part 1 of 2.
+IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
+                       PRE_TestOnlyWellFormedFeaturesPersisted) {
+  // Default values should be returned.
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableFoo));
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableBar));
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableBaz));
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableBat));
+
+  // Set both good parameters...
+  base::DictionaryValue features;
+  features.SetBoolean("enable_foo", true);
+  features.SetBoolean("enable_bat", false);
+
+  // ... and bad parameters.
+  features.SetString("enable_bar", "False");
+  features.Set("enable_baz", base::MakeUnique<base::ListValue>());
+
+  SetFeatures(features);
+}
+
+// Test that only well-formed features are persisted to disk. Part 2 of 2.
+IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
+                       TestOnlyWellFormedFeaturesPersisted) {
+  // Only the well-formed parameters should be overriden.
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableFoo));
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableBat));
+
+  // The other should take default values.
+  ASSERT_TRUE(base::FeatureList::IsEnabled(kEnableBar));
+  ASSERT_FALSE(base::FeatureList::IsEnabled(kEnableBaz));
+}
+
+}  // namespace shell
+}  // namespace chromecast