Add tests for InputDevice/TouchscreenDevice StructTraits.

ui/events/devices/mojo/device_struct_traits_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 "base/files/file_path.h"
+#include "base/message_loop/message_loop.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/events/devices/input_device.h"
+#include "ui/events/devices/mojo/device_traits_test_service.mojom.h"
+#include "ui/events/devices/touchscreen_device.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace ui {
+
+namespace {
+
+class DeviceStructTraitsTest : public testing::Test,
+                               public mojom::DeviceTraitsTestService {
+ public:
+  DeviceStructTraitsTest() {}
+
+ protected:
+  mojom::DeviceTraitsTestServicePtr GetTraitsTestProxy() {
+    return traits_test_bindings_.CreateInterfacePtrAndBind(this);
+  }
+
+ private:
+  // DeviceTraitsTestService:
+  void EchoInputDevice(const InputDevice& in,
+                       const EchoInputDeviceCallback& callback) override {
+    callback.Run(in);
+  }
+
+  void EchoTouchscreenDevice(
+      const TouchscreenDevice& in,
+      const EchoTouchscreenDeviceCallback& callback) override {
+    callback.Run(in);
+  }
+
+  base::MessageLoop loop_;  // Needed otherwise DCHECK fails.

[sadrul, 2016/06/27 15:17:39]

Which DCHECK? (I don't think the comment is all that useful. Perhaps something
more like "A MessageLoop is needed for mojo IPC to work."

[kylechar, 2016/06/27 15:25:59]

Done.

+  mojo::BindingSet<DeviceTraitsTestService> traits_test_bindings_;
+
+  DISALLOW_COPY_AND_ASSIGN(DeviceStructTraitsTest);
+};
+
+}  // namespace
+
+TEST_F(DeviceStructTraitsTest, InputDevice) {
+  InputDevice input(15,                     // id
+                    INPUT_DEVICE_INTERNAL,  // type
+                    "Input Device");        // name
+  input.sys_path = base::FilePath::FromUTF8Unsafe("/dev/input/event14");
+  input.vendor_id = 1000;
+  input.product_id = 2000;
+
+  mojom::DeviceTraitsTestServicePtr proxy = GetTraitsTestProxy();
+  InputDevice output;
+  proxy->EchoInputDevice(input, &output);
+
+  EXPECT_EQ(input.id, output.id);
+  EXPECT_EQ(input.type, output.type);
+  EXPECT_EQ(input.name, output.name);
+  EXPECT_EQ(input.sys_path, output.sys_path);
+  EXPECT_EQ(input.vendor_id, output.vendor_id);
+  EXPECT_EQ(input.product_id, output.product_id);
+}
+
+TEST_F(DeviceStructTraitsTest, TouchscreenDevice) {
+  TouchscreenDevice input(10,                    // id
+                          INPUT_DEVICE_UNKNOWN,  // type
+                          "Touchscreen Device",  // name
+                          gfx::Size(123, 456),   // size
+                          3);                    // touch_points
+  // Not setting sys_path intentionally.
+  input.vendor_id = 0;
+  input.product_id = 0;

[sadrul, 2016/06/27 15:17:39]

Set some non-zero values here?

[kylechar, 2016/06/27 15:25:59]

It seems like these often end up being zero in real data, so checking that case.

+
+  mojom::DeviceTraitsTestServicePtr proxy = GetTraitsTestProxy();
+  TouchscreenDevice output;
+  proxy->EchoTouchscreenDevice(input, &output);
+
+  EXPECT_EQ(input.id, output.id);
+  EXPECT_EQ(input.type, output.type);
+  EXPECT_EQ(input.name, output.name);
+  EXPECT_EQ(input.sys_path, output.sys_path);
+  EXPECT_EQ(input.vendor_id, output.vendor_id);
+  EXPECT_EQ(input.product_id, output.product_id);
+  EXPECT_EQ(input.size, output.size);
+  EXPECT_EQ(input.touch_points, output.touch_points);
+}
+
+}  // namespace ui