Restart the host when the third party auth certificate changes

remoting/host/linux/certificate_watcher_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.
+
+#include "remoting/host/linux/certificate_watcher.h"

[Sergey Ulanov, 2016/03/29 19:40:05]

nit: emtpy line after this include

[Yuwei, 2016/03/29 19:57:03]

Acknowledged.

[Yuwei, 2016/03/30 18:47:45]

Done.

+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace remoting {
+  class MockCertificateWatcherImpl : public CertificateWatcherImplInterface {

[Sergey Ulanov, 2016/03/29 19:40:04]

add empty line after namespace.
indentation.

[Sergey Ulanov, 2016/03/29 19:40:05]

So this test mocks the most interesting part of the code being tested. unittests
like this are rarely useful. I think it should be easy to test the real
implementation without faking any of the internal behavior. Just create a temp
directory, install the watcher and verify that it does the right thing.
ScopedTempDir class from base/files/scoped_temp_dir.h might be useful to
implement this.

[Yuwei, 2016/03/29 19:57:02]

Acknowledged.

[Yuwei, 2016/03/29 19:57:02]

Acknowledged.

[Yuwei, 2016/03/30 18:47:45]

Class rewritten to test the real situation of watching a file.

+   public:
+    void SetWatcher(CertificateWatcher* watcher) { watcher_ = watcher; }
+    void Start() override {
+      start_count++;
+      started_ = true;
+    }
+    void Stop() override {
+      stop_count++;
+      started_ = false;
+    }
+    void ScheduleSuicide() override { suicide_count++; }
+    void TriggerUpdate() { if (started_) watcher_->OnUpdate(); }
+    int start_count = 0;
+    int stop_count = 0;
+    int suicide_count = 0;
+   private:

[Sergey Ulanov, 2016/03/29 19:40:05]

empty line above this one.

[Yuwei, 2016/03/29 19:57:02]

Acknowledged.

+    CertificateWatcher* watcher_;
+    bool started_ = false;
+  };
+
+  void CreateTestWatcher(MockCertificateWatcherImpl** pImpl,
+                         CertificateWatcher** pWatcher) {

[Sergey Ulanov, 2016/03/29 19:40:05]

We don't use Hungarian notation, so this should be just "watcher", not pWatcher.
https://google.github.io/styleguide/cppguide.html#General_Naming_Rules

[Yuwei, 2016/03/29 19:57:02]

Acknowledged.

+    MockCertificateWatcherImpl *impl = new MockCertificateWatcherImpl();
+    CertificateWatcher* watcher = new CertificateWatcher(impl);
+    impl->SetWatcher(watcher);
+    *pImpl = impl;
+    *pWatcher = watcher;
+  }
+
+  TEST(CertificateWatcherTest, StartAndStop) {
+    MockCertificateWatcherImpl* impl = nullptr;
+    CertificateWatcher* watcher = nullptr;
+    CreateTestWatcher(&impl, &watcher);
+
+    EXPECT_EQ(0, impl->suicide_count);
+    impl->TriggerUpdate();
+    EXPECT_EQ(0, impl->suicide_count);
+    watcher->Start();
+    EXPECT_EQ(0, impl->suicide_count);
+    impl->TriggerUpdate();
+    EXPECT_EQ(1, impl->suicide_count);
+    watcher->Stop();
+    EXPECT_EQ(1, impl->suicide_count);
+    impl->TriggerUpdate();
+    EXPECT_EQ(1, impl->suicide_count);
+
+    EXPECT_EQ(1, impl->start_count);
+    EXPECT_EQ(1, impl->stop_count);
+
+    delete watcher;
+  }
+
+  TEST(CertificateWatcherTest, InhibitDeferSuicide) {
+    MockCertificateWatcherImpl* impl = nullptr;
+    CertificateWatcher* watcher = nullptr;
+    CreateTestWatcher(&impl, &watcher);
+
+    watcher->Start();
+    EXPECT_EQ(0, impl->suicide_count);
+    watcher->Inhibit();
+    EXPECT_EQ(0, impl->suicide_count);
+    impl->TriggerUpdate();
+    EXPECT_EQ(0, impl->suicide_count);
+    watcher->Uninhibit();
+    EXPECT_EQ(1, impl->suicide_count);
+
+    delete watcher;
+  }
+
+  TEST(CertificateWatcherTest, UninhibitAndSuicide) {
+    MockCertificateWatcherImpl* impl = nullptr;
+    CertificateWatcher* watcher = nullptr;
+    CreateTestWatcher(&impl, &watcher);
+
+    watcher->Start();
+    EXPECT_EQ(0, impl->suicide_count);
+    watcher->Inhibit();
+    EXPECT_EQ(0, impl->suicide_count);
+    watcher->Uninhibit();
+    EXPECT_EQ(0, impl->suicide_count);
+    impl->TriggerUpdate();
+    EXPECT_EQ(1, impl->suicide_count);
+
+    delete watcher;
+  }
+
+  TEST(CertificateWatcherTest, SuicideScheduleOnlyOnce) {
+    MockCertificateWatcherImpl* impl = nullptr;
+    CertificateWatcher* watcher = nullptr;
+    CreateTestWatcher(&impl, &watcher);
+
+    watcher->Start();
+    EXPECT_EQ(0, impl->suicide_count);
+    impl->TriggerUpdate();
+    EXPECT_EQ(1, impl->suicide_count);
+    impl->TriggerUpdate();
+    EXPECT_EQ(1, impl->suicide_count);
+
+    delete watcher;
+  }
+}