Basic UkmService implementation

components/ukm/ukm_service_unittest.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 "components/ukm/ukm_service.h"
+
+#include "base/test/test_simple_task_runner.h"
+#include "base/threading/thread_task_runner_handle.h"
+#include "components/metrics/test_metrics_service_client.h"
+#include "components/prefs/testing_pref_service.h"
+#include "components/ukm/ukm_pref_names.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace ukm {
+
+namespace {
+
+class UkmServiceTest : public testing::Test {
+ public:
+  UkmServiceTest()
+      : task_runner_(new base::TestSimpleTaskRunner),
+        task_runner_handle_(task_runner_) {
+    UkmService::RegisterPrefs(prefs_.registry());
+    prefs_.ClearPref(prefs::kUkmClientId);
+    prefs_.ClearPref(prefs::kUkmPersistedLogs);
+  }
+
+  int GetPersistedLogCount() {
+    const base::ListValue* list_value =
+        prefs_.GetList(prefs::kUkmPersistedLogs);
+    return list_value->GetSize();
+  }
+
+ protected:
+  TestingPrefServiceSimple prefs_;
+  metrics::TestMetricsServiceClient client_;
+
+  scoped_refptr<base::TestSimpleTaskRunner> task_runner_;
+  base::ThreadTaskRunnerHandle task_runner_handle_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(UkmServiceTest);
+};
+
+}  // namespace
+
+TEST_F(UkmServiceTest, EnableDisableSchedule) {
+  UkmService service(&prefs_, &client_);
+  EXPECT_FALSE(task_runner_->HasPendingTask());
+  service.Initialize();
+  EXPECT_TRUE(task_runner_->HasPendingTask());
+  // Allow initialization to complete.
+  task_runner_->RunUntilIdle();
+  service.EnableReporting();
+  EXPECT_TRUE(task_runner_->HasPendingTask());
+  service.DisableReporting();
+  task_runner_->RunPendingTasks();
+  EXPECT_FALSE(task_runner_->HasPendingTask());
+}
+
+TEST_F(UkmServiceTest, PersistAndPurge) {
+  UkmService service(&prefs_, &client_);
+  EXPECT_EQ(GetPersistedLogCount(), 0);
+  service.Initialize();
+  task_runner_->RunUntilIdle();
+  service.EnableReporting();
+  // Should init, generate a log, and unsuccessfully attempt an upload.
+  task_runner_->RunPendingTasks();
+  // Flushes the generated log to disk and generates a new one.
+  service.Flush();
+  EXPECT_EQ(GetPersistedLogCount(), 2);
+  service.Purge();
+  EXPECT_EQ(GetPersistedLogCount(), 0);
+}
+
+}  // namespace ukm