Revert of Reland "[Chromecast] Use base::FeatureList to control features."

chromecast/browser/test/cast_features_browsertest.cc

-// 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 <cstdint>
-#include <unordered_set>
-
-#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"
-#include "components/prefs/scoped_user_pref_update.h"
-
-// PLEASE READ:
-// 1) These tests are run in groups to simulate a restart of cast_shell. Each
-//    test (ex. TestFoo) is accompanied by one or more tests which are
-//    guaranteed to run before it (ex. PRE_TestFoo, PRE_PRE_TestFoo). PRE_ is a
-//    special prefix used by content::BrowserTest to enforce test ordering among
-//    tests of the same name. If a prefixed test fails, the unprefixed test
-//    will not run. The tests use this behavior to test persisted state between
-//    subsequent cast_shell runs. HOWEVER, tests which do not share a common
-//    name have NO guarantee of ordering (ex. TestBar may run before, after, or
-//    during PRE_TestFoo). Therefore, tests with different names should be
-//    entirely independent.
-//
-// 2) Because of the last note in (1), when testing persistent features, do not
-//    re-use the same feature in more than one set of tests. Because the order
-//    of execution is not guaranteed between test sets, this may cause the tests
-//    to flake, depending on how gtest decides to schedule them.
-//    For example, TestFoo and TestBar should not both try to read and write
-//    kTestFeat1 in the PrefStore. This makes the tests flaky and co-dependent.
-//
-// 3) Generally, the model should look like this:
-//
-//      IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, PRE_PRE_TestFoo) {
-//        // Reset the state of the features.
-//        CleareFeaturesFromPrefs({kFooFeature1, kFooFeature2});
-//      }
-//
-//      IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, PRE_TestFoo) {
-//        // Test the default state of the features...
-//        EXPECT_TRUE(...);
-//
-//        // ... then persist overrides to disk.
-//        SetFeatures(features_dict);  // contains override for kFooFeature1
-//      }
-//
-//      IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, TestFoo) {
-//        // Test that the feature override was properly persisted.
-//        EXPECT_FALSE(...);
-//      }
-//
-//    Note that in the example above, kFooFeatureX should not be used in tests
-//    other than (PRE_)*FooTest, to ensure test indepdendence. An unrelated
-//    BarTest should use features like KBarFeatureX.
-//
-
-namespace chromecast {
-namespace shell {
-namespace {
-
-// Note: When adding new features for existing tests, please extend on the
-// current block of features, by adding another sequentially-numbered feature.
-// When adding a new test, please add a new block of features, the numbering for
-// which is based at the next available multiple of 10.
-
-// For use in TestFeaturesActivateOnBoot only.
-const base::Feature kTestFeat1("test_feat_1",
-                               base::FEATURE_DISABLED_BY_DEFAULT);
-const base::Feature kTestFeat2("test_feat_2", base::FEATURE_ENABLED_BY_DEFAULT);
-const base::Feature kTestFeat3("test_feat_3",
-                               base::FEATURE_DISABLED_BY_DEFAULT);
-const base::Feature kTestFeat4("test_feat_4", base::FEATURE_ENABLED_BY_DEFAULT);
-
-// For use in TestParamsActivateOnBoot only.
-const base::Feature kTestFeat11("test_feat_11",
-                                base::FEATURE_DISABLED_BY_DEFAULT);
-
-// For use in TestOnlyWellFormedFeaturesPersisted only.
-const base::Feature kTestFeat21("test_feat_21",
-                                base::FEATURE_DISABLED_BY_DEFAULT);
-const base::Feature kTestFeat22("test_feat_22",
-                                base::FEATURE_ENABLED_BY_DEFAULT);
-const base::Feature kTestFeat23("test_feat_23",
-                                base::FEATURE_DISABLED_BY_DEFAULT);
-const base::Feature kTestFeat24("test_feat_24",
-                                base::FEATURE_ENABLED_BY_DEFAULT);
-
-}  // namespace
-
-class CastFeaturesBrowserTest : public CastBrowserTest {
- public:
-  CastFeaturesBrowserTest() {}
-  ~CastFeaturesBrowserTest() override {}
-
-  static PrefService* pref_service() {
-    return CastBrowserProcess::GetInstance()->pref_service();
-  }
-
-  // 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);
-    ScopedUserPrefUpdate<base::DictionaryValue, base::Value::Type::DICTIONARY>
-        dict(pref_service(), prefs::kLatestDCSFeatures);
-    dict->MergeDictionary(&pref_features);
-    pref_service()->CommitPendingWrite();
-  }
-
-  // Clears |features| from the PrefStore. Should be called in a PRE_PRE_*
-  // method for any tested feature in a test to ensure consistent state.
-  void ClearFeaturesFromPrefs(std::vector<base::Feature> features) {
-    ScopedUserPrefUpdate<base::DictionaryValue, base::Value::Type::DICTIONARY>
-        dict(pref_service(), prefs::kLatestDCSFeatures);
-    for (auto f : features)
-      dict->Remove(f.name, nullptr);
-    pref_service()->CommitPendingWrite();
-  }
-
-  // Write |experiment_ids| 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 SetExperimentIds(
-      const std::unordered_set<int32_t>& experiment_ids) {
-    base::ListValue list;
-    for (auto id : experiment_ids)
-      list.AppendInteger(id);
-    pref_service()->Set(prefs::kActiveDCSExperiments, list);
-    pref_service()->CommitPendingWrite();
-  }
-
-  // Clear the set experiment id's.
-  void ClearExperimentIds() {
-    pref_service()->Set(prefs::kActiveDCSExperiments, base::ListValue());
-    pref_service()->CommitPendingWrite();
-  }
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(CastFeaturesBrowserTest);
-};
-
-// Test that set features activate on the next boot. Part 1 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
-                       PRE_PRE_TestFeaturesActivateOnBoot) {
-  ClearFeaturesFromPrefs({kTestFeat1, kTestFeat2, kTestFeat3, kTestFeat4});
-}
-
-// Test that set features activate on the next boot. Part 2 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
-                       PRE_TestFeaturesActivateOnBoot) {
-  // Default values should be returned.
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat1));
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat2));
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat3));
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat4));
-
-  // Set the features to be used on next boot.
-  base::DictionaryValue features;
-  features.SetBoolean("test_feat_1", true);
-  features.SetBoolean("test_feat_4", false);
-  SetFeatures(features);
-
-  // Default values should still be returned until next boot.
-  EXPECT_FALSE(base::FeatureList::IsEnabled(kTestFeat1));
-  EXPECT_TRUE(base::FeatureList::IsEnabled(kTestFeat2));
-  EXPECT_FALSE(base::FeatureList::IsEnabled(kTestFeat3));
-  EXPECT_TRUE(base::FeatureList::IsEnabled(kTestFeat4));
-}
-
-// Test that features activate on the next boot. Part 3 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, TestFeaturesActivateOnBoot) {
-  // Overriden values set in test case above should be set.
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat1));
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat2));
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat3));
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat4));
-}
-
-// Test that features with params activate on boot. Part 1 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
-                       PRE_PRE_TestParamsActivateOnBoot) {
-  ClearFeaturesFromPrefs({kTestFeat11});
-}
-
-// Test that features with params activate on boot. Part 2 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, PRE_TestParamsActivateOnBoot) {
-  // Default value should be returned.
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat11));
-
-  // 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("test_feat_11", std::move(params));
-  SetFeatures(features);
-
-  // Default value should still be returned until next boot.
-  EXPECT_FALSE(base::FeatureList::IsEnabled(kTestFeat11));
-}
-
-// Test that features with params activate on boot. Part 3 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, TestParamsActivateOnBoot) {
-  // Check that the feature is now enabled.
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat11));
-
-  // Check that the params are populated and correct.
-  ASSERT_TRUE(base::GetFieldTrialParamByFeatureAsBool(
-      kTestFeat11, "bool_param", false /* default_value */));
-  ASSERT_FALSE(base::GetFieldTrialParamByFeatureAsBool(
-      kTestFeat11, "bool_param_2", true /* default_value */));
-  ASSERT_EQ("foo",
-            base::GetFieldTrialParamValueByFeature(kTestFeat11, "str_param"));
-  ASSERT_EQ(76543, base::GetFieldTrialParamByFeatureAsInt(
-                       kTestFeat11, "int_param", 0 /* default_value */));
-  ASSERT_EQ(3.14159, base::GetFieldTrialParamByFeatureAsDouble(
-                         kTestFeat11, "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(kTestFeat11, &params_out));
-  ASSERT_EQ(5u, params_out.size());
-}
-
-// Test that only well-formed features are persisted to disk. Part 1 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
-                       PRE_PRE_TestOnlyWellFormedFeaturesPersisted) {
-  ClearFeaturesFromPrefs({kTestFeat21, kTestFeat22, kTestFeat23, kTestFeat24});
-}
-
-// Test that only well-formed features are persisted to disk. Part 2 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
-                       PRE_TestOnlyWellFormedFeaturesPersisted) {
-  // Default values should be returned.
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat21));
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat22));
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat23));
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat24));
-
-  // Set both good parameters...
-  base::DictionaryValue features;
-  features.SetBoolean("test_feat_21", true);
-  features.SetBoolean("test_feat_24", false);
-
-  // ... and bad parameters.
-  features.SetString("test_feat_22", "False");
-  features.Set("test_feat_23", 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(kTestFeat21));
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat24));
-
-  // The other should take default values.
-  ASSERT_TRUE(base::FeatureList::IsEnabled(kTestFeat22));
-  ASSERT_FALSE(base::FeatureList::IsEnabled(kTestFeat23));
-}
-
-// Test that experiment ids are persisted to disk. Part 1 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
-                       PRE_PRE_TestExperimentIdsPersisted) {
-  ClearExperimentIds();
-}
-
-// Test that experiment ids are persisted to disk. Part 2 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest,
-                       PRE_TestExperimentIdsPersisted) {
-  // No experiments should be set.
-  ASSERT_TRUE(GetDCSExperimentIds().empty());
-
-  // Set a test list of experiments.
-  std::unordered_set<int32_t> ids({1234, 1, 4000});
-  SetExperimentIds(ids);
-
-  // No experiments should be set, still.
-  ASSERT_TRUE(GetDCSExperimentIds().empty());
-}
-
-// Test that experiment ids are persisted to disk. Part 3 of 3.
-IN_PROC_BROWSER_TEST_F(CastFeaturesBrowserTest, TestExperimentIdsPersisted) {
-  // The experiments set in the last run should be active now.
-  std::unordered_set<int32_t> ids({1234, 1, 4000});
-  ASSERT_EQ(ids, GetDCSExperimentIds());
-}
-
-}  // namespace shell
-}  // namespace chromecast