Add log source to read from one DebugDaemon log

chrome/browser/chromeos/system_logs/single_debug_daemon_log_source_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 "chrome/browser/chromeos/system_logs/single_debug_daemon_log_source.h"
+
+#include <string>
+
+#include "base/bind.h"
+#include "base/macros.h"
+#include "base/memory/ptr_util.h"
+#include "base/run_loop.h"
+#include "base/test/scoped_task_environment.h"
+#include "chromeos/dbus/dbus_thread_manager.h"
+#include "chromeos/dbus/fake_debug_daemon_client.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace system_logs {
+
+using SupportedSource = SingleDebugDaemonLogSource::SupportedSource;
+
+class SingleDebugDaemonLogSourceTest : public ::testing::Test {
+ public:
+  SingleDebugDaemonLogSourceTest()
+      : scoped_task_environment_(
+            base::test::ScopedTaskEnvironment::MainThreadType::UI),
+        fetch_callback_(
+            base::Bind(&SingleDebugDaemonLogSourceTest::OnFetchComplete,
+                       base::Unretained(this))),
+        num_callback_calls_(0) {}
+
+  void SetUp() override {
+    // Since no debug daemon will be available during a unit test, use
+    // FakeDebugDaemonClient to provide dummy DebugDaemonClient functionality.
+    chromeos::DBusThreadManager::GetSetterForTesting()->SetDebugDaemonClient(
+        std::unique_ptr<chromeos::DebugDaemonClient>(
+            new chromeos::FakeDebugDaemonClient));

[afakhry, 2017/06/22 23:34:15]

Nit: MakeUnique<>

[Simon Que, 2017/06/23 05:06:40]

Done.

+  }
+
+  void TearDown() override {
+    chromeos::DBusThreadManager::GetSetterForTesting()->SetDebugDaemonClient(
+        nullptr);
+  }
+
+ protected:
+  const SysLogsSourceCallback& fetch_callback() const {
+    return fetch_callback_;
+  }
+
+  int num_callback_calls() const { return num_callback_calls_; }
+
+  const SystemLogsResponse& response() const { return response_; }
+
+  void ClearResponse() { response_.clear(); }
+
+ private:
+  void OnFetchComplete(SystemLogsResponse* response) {
+    ++num_callback_calls_;
+    response_ = *response;
+  }
+
+  // For running scheduled tasks.
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
+
+  // Pre-made callback object for passing OnFetchComplete() to an asynchronous
+  // function.
+  const SysLogsSourceCallback fetch_callback_;
+
+  // Used to verify that OnFetchComplete was called the correct number of times.
+  int num_callback_calls_;
+
+  // Stores results from the log source.
+  SystemLogsResponse response_;
+
+  DISALLOW_COPY_AND_ASSIGN(SingleDebugDaemonLogSourceTest);
+};
+
+TEST_F(SingleDebugDaemonLogSourceTest, SingleCall) {
+  SingleDebugDaemonLogSource source(SupportedSource::kModetest);
+
+  source.Fetch(fetch_callback());
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_EQ(1, num_callback_calls());
+  ASSERT_EQ(1U, response().size());
+
+  EXPECT_EQ("modetest", response().begin()->first);
+  EXPECT_EQ("Response from individual log", response().begin()->second);
+}
+
+TEST_F(SingleDebugDaemonLogSourceTest, MultipleCalls) {
+  SingleDebugDaemonLogSource source(SupportedSource::kLsusb);
+
+  source.Fetch(fetch_callback());
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_EQ(1, num_callback_calls());
+  ASSERT_EQ(1U, response().size());
+
+  EXPECT_EQ("lsusb", response().begin()->first);
+  EXPECT_EQ("Response from individual log", response().begin()->second);
+
+  ClearResponse();
+
+  source.Fetch(fetch_callback());
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_EQ(2, num_callback_calls());
+  ASSERT_EQ(1U, response().size());
+
+  EXPECT_EQ("lsusb", response().begin()->first);
+  EXPECT_EQ("Response from individual log", response().begin()->second);
+
+  ClearResponse();
+
+  source.Fetch(fetch_callback());
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_EQ(3, num_callback_calls());
+  ASSERT_EQ(1U, response().size());
+
+  EXPECT_EQ("lsusb", response().begin()->first);
+  EXPECT_EQ("Response from individual log", response().begin()->second);
+}
+
+TEST_F(SingleDebugDaemonLogSourceTest, MultipleSources) {
+  SingleDebugDaemonLogSource source1(SupportedSource::kModetest);
+  source1.Fetch(fetch_callback());
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_EQ(1, num_callback_calls());
+  ASSERT_EQ(1U, response().size());
+
+  EXPECT_EQ("modetest", response().begin()->first);
+  EXPECT_EQ("Response from individual log", response().begin()->second);
+
+  ClearResponse();
+
+  SingleDebugDaemonLogSource source2(SupportedSource::kLsusb);
+  source2.Fetch(fetch_callback());
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_EQ(2, num_callback_calls());
+  ASSERT_EQ(1U, response().size());
+
+  EXPECT_EQ("lsusb", response().begin()->first);
+  EXPECT_EQ("Response from individual log", response().begin()->second);
+}
+
+}  // namespace system_logs