MD Settings: implement metrics reporting checkbox on desktop

chrome/browser/ui/webui/settings/metrics_reporting_handler_unittest.cc

+// Copyright 2016 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.
+
+#if defined(GOOGLE_CHROME_BUILD) && !defined(OS_CHROMEOS)
+
+#include "chrome/browser/ui/webui/settings/metrics_reporting_handler.h"
+
+#include "base/memory/ptr_util.h"
+#include "base/values.h"
+#include "chrome/test/base/scoped_testing_local_state.h"
+#include "chrome/test/base/testing_browser_process.h"
+#include "components/metrics/metrics_pref_names.h"
+#include "components/policy/core/browser/browser_policy_connector.h"
+#include "components/policy/core/common/mock_configuration_policy_provider.h"
+#include "components/policy/core/common/policy_map.h"
+#include "components/policy/core/common/policy_types.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/browser/web_ui.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "content/public/test/test_web_ui.h"
+#include "policy/policy_constants.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace settings {
+
+class TestingMetricsReportingHandler : public MetricsReportingHandler {
+ public:
+  using MetricsReportingHandler::set_web_ui;
+  using MetricsReportingHandler::HandleGetMetricsReporting;
+};
+
+using testing::_;
+using testing::Return;
+
+class MetricsReportingHandlerTest : public testing::Test {
+ public:
+  MetricsReportingHandlerTest() {
+    // Local state must be set up before |handler_|.
+    TestingBrowserProcess::CreateInstance();
+    local_state_.reset(new ScopedTestingLocalState(
+        TestingBrowserProcess::GetGlobal()));
+
+    handler_.reset(new TestingMetricsReportingHandler);
+    handler_->set_web_ui(&test_web_ui_);
+
+    EXPECT_CALL(provider_, IsInitializationComplete(testing::_)).WillRepeatedly(
+        testing::Return(true));
+    policy::BrowserPolicyConnector::SetPolicyProviderForTesting(&provider_);
+  }
+
+  void SetUp() override {
+    ASSERT_EQ(local_state(), g_browser_process->local_state());
+    EXPECT_TRUE(test_web_ui()->call_data().empty());
+
+    base::ListValue args;
+    args.Append(base::WrapUnique(new base::FundamentalValue(1)));
+    handler()->HandleGetMetricsReporting(&args);
+
+    EXPECT_TRUE(handler()->IsJavascriptAllowed());
+    EXPECT_EQ(1u, test_web_ui()->call_data().size());
+
+    test_web_ui()->ClearTrackedCalls();
+  }
+
+  PrefService* local_state() { return local_state_->Get(); }
+  TestingMetricsReportingHandler* handler() { return handler_.get(); }
+  content::TestWebUI* test_web_ui() { return &test_web_ui_; }
+  policy::PolicyMap* map() { return &map_; }
+  policy::MockConfigurationPolicyProvider* provider() { return &provider_; }

[dschuyler, 2016/08/10 18:55:16]

For test_web_ui(), map(), and provider() can we 
return references?

[Dan Beam, 2016/08/10 19:41:59]

we could... but what's the benefit?

the google c++ style guide discourages accepting *params* as non-const
references.

returning mutable pointers to internal state is way more common in chrome:

$ git grep -P '(?<!const)\s[:\w]+\&\s[\w:]+\(' | grep -v third_party | wc -l
763

$ git grep -P '(?<!const)\s[:\w]+\*\s[\w:]+\(' | grep -v third_party | wc -l
19676

+
+ private:
+  content::TestBrowserThreadBundle thread_bundle_;
+  content::TestWebUI test_web_ui_;
+  std::unique_ptr<ScopedTestingLocalState> local_state_;
+  std::unique_ptr<TestingMetricsReportingHandler> handler_;
+
+  policy::MockConfigurationPolicyProvider provider_;
+  policy::PolicyMap map_;
+};
+
+TEST_F(MetricsReportingHandlerTest, PrefChangesNotifyPage) {
+  // Toggle the pref.
+  local_state()->SetBoolean(
+      metrics::prefs::kMetricsReportingEnabled,
+      !local_state()->GetBoolean(metrics::prefs::kMetricsReportingEnabled));
+  EXPECT_EQ(1u, test_web_ui()->call_data().size());
+
+  test_web_ui()->ClearTrackedCalls();
+  handler()->DisallowJavascript();
+
+  // Toggle the pref again, while JavaScript is disabled.
+  local_state()->SetBoolean(
+      metrics::prefs::kMetricsReportingEnabled,
+      !local_state()->GetBoolean(metrics::prefs::kMetricsReportingEnabled));
+  EXPECT_TRUE(test_web_ui()->call_data().empty());
+}
+
+TEST_F(MetricsReportingHandlerTest, PolicyChangesNotifyPage) {
+  // Change the policy, check that the page was notified.
+  map()->Set(policy::key::kMetricsReportingEnabled,
+             policy::POLICY_LEVEL_MANDATORY,
+             policy::POLICY_SCOPE_USER,
+             policy::POLICY_SOURCE_CLOUD,
+             base::WrapUnique(new base::FundamentalValue(true)),
+             nullptr);
+  provider()->UpdateChromePolicy(*map());
+  EXPECT_EQ(1u, test_web_ui()->call_data().size());
+
+  test_web_ui()->ClearTrackedCalls();
+  handler()->DisallowJavascript();
+
+  // Policies changing while JavaScript is disabled shouldn't notify the page.
+  map()->Set(policy::key::kMetricsReportingEnabled,
+             policy::POLICY_LEVEL_MANDATORY,
+             policy::POLICY_SCOPE_USER,
+             policy::POLICY_SOURCE_CLOUD,
+             base::WrapUnique(new base::FundamentalValue(false)),
+             nullptr);
+  provider()->UpdateChromePolicy(*map());
+  EXPECT_TRUE(test_web_ui()->call_data().empty());
+}
+
+}  // namespace settings
+
+#endif  // defined(GOOGLE_CHROME_BUILD) && !defined(OS_CHROMEOS)