[Chromoting] Add a filter that will stop the host sending unnecessary clipboard events to the clien…

remoting/protocol/clipboard_echo_filter_unittest.cc

Index: remoting/protocol/clipboard_echo_filter_unittest.cc
diff --git a/remoting/protocol/clipboard_echo_filter_unittest.cc b/remoting/protocol/clipboard_echo_filter_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..35e70b186173b6a391cb5292e758b7ff3fde7683
--- /dev/null
+++ b/remoting/protocol/clipboard_echo_filter_unittest.cc
@@ -0,0 +1,109 @@
+// Copyright (c) 2012 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/protocol/clipboard_echo_filter.h"
+
+#include "remoting/proto/event.pb.h"
+#include "remoting/protocol/protocol_mock_objects.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using ::testing::_;
+using ::testing::InSequence;
+
+namespace remoting {
+namespace protocol {
+
+MATCHER_P2(EqualsClipboardEvent, mime_type, data, "") {
+  return arg.mime_type() == mime_type && arg.data() == data;
+}
+
+static ClipboardEvent MakeClipboardEvent(const std::string& mime_type,
+                                  const std::string& data) {
+  ClipboardEvent event;
+  event.set_mime_type(mime_type);
+  event.set_data(data);
+  return event;
+}
+
+// Check that a clipboard event to the host filters out only a subsequent
+// identical event from the host.

[Wez, 2012/05/21 22:33:15]

nit: Suggest "... the host only filters out events identical to the most recent
clipboard content from the client".

[simonmorris, 2012/05/21 23:01:33]

Done.

+TEST(ClipboardEchoFilterTest, FromClientBlocksIdenticalEventToClient) {
+  MockClipboardStub client_stub;
+  MockClipboardStub host_stub;
+
+  {
+    InSequence s;
+    EXPECT_CALL(host_stub,
+                InjectClipboardEvent(EqualsClipboardEvent("text", "a")));
+    EXPECT_CALL(host_stub,
+                InjectClipboardEvent(EqualsClipboardEvent("text", "b")));
+    EXPECT_CALL(client_stub,
+                InjectClipboardEvent(EqualsClipboardEvent("text", "a")));
+    EXPECT_CALL(host_stub,
+                InjectClipboardEvent(EqualsClipboardEvent("image", "a")));
+    EXPECT_CALL(client_stub,
+                InjectClipboardEvent(EqualsClipboardEvent("text", "a")));
+  }
+
+  ClipboardEchoFilter filter;
+  filter.set_client_stub(&client_stub);
+  filter.set_host_stub(&host_stub);
+
+  filter.get_host_filter()->InjectClipboardEvent(
+      MakeClipboardEvent("text", "a"));
+  // We know the client has ("text", "a") on its clipboard, so don't send it
+  // the same item.

[Wez, 2012/05/21 22:33:15]

nit: This reads as documentation of what we're doing; we actually _do_ want to
inject the same content, and verify that it's properly filtered.

[simonmorris, 2012/05/21 23:01:33]

Done.

+  filter.get_client_filter()->InjectClipboardEvent(
+      MakeClipboardEvent("text", "a"));
+  filter.get_host_filter()->InjectClipboardEvent(
+      MakeClipboardEvent("text", "b"));
+  filter.get_client_filter()->InjectClipboardEvent(
+      MakeClipboardEvent("text", "a"));
+  filter.get_host_filter()->InjectClipboardEvent(
+      MakeClipboardEvent("image", "a"));
+  filter.get_client_filter()->InjectClipboardEvent(
+      MakeClipboardEvent("text", "a"));
+}
+
+// Check what happens if no host stub is set.

[Wez, 2012/05/21 22:33:15]

Can you update this description to indicate the expected behaviour that you're
testing for?  Otherwise it's not clear why we even need to test it the behaviour
rather than relay on non-NULL CHECKs.

[simonmorris, 2012/05/21 23:01:33]

Done.

+TEST(ClipboardEchoFilterTest, NoToHost) {
+  MockClipboardStub client_stub;
+  MockClipboardStub host_stub;
+
+  EXPECT_CALL(host_stub,
+              InjectClipboardEvent(EqualsClipboardEvent("text", "a")));
+
+  ClipboardEchoFilter filter;
+  ClipboardEvent event = MakeClipboardEvent("text", "a");
+  filter.get_host_filter()->InjectClipboardEvent(event);
+
+  filter.set_client_stub(&client_stub);
+  filter.get_host_filter()->InjectClipboardEvent(event);
+
+  filter.set_host_stub(&host_stub);
+  filter.get_host_filter()->InjectClipboardEvent(event);
+}
+
+// Check what happens if no client stub is set.
+TEST(ClipboardEchoFilter, NoToClient) {
+  MockClipboardStub client_stub;
+  MockClipboardStub host_stub;
+
+  EXPECT_CALL(client_stub,
+              InjectClipboardEvent(EqualsClipboardEvent("text", "a")));
+
+  ClipboardEchoFilter filter;
+  ClipboardEvent event = MakeClipboardEvent("text", "a");
+  filter.get_client_filter()->InjectClipboardEvent(event);
+
+  filter.set_host_stub(&host_stub);
+  filter.get_client_filter()->InjectClipboardEvent(event);
+
+  filter.set_client_stub(&client_stub);
+  filter.get_client_filter()->InjectClipboardEvent(event);
+}
+
+}  // namespace protocol
+}  // namespace remoting