Add gesture support in views::ResizeArea

ui/views/controls/resize_area_unittest.cc

Index: ui/views/controls/resize_area_unittest.cc
diff --git a/ui/views/controls/resize_area_unittest.cc b/ui/views/controls/resize_area_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0dd9107260fd8caacf1268a5a239db0dca9a542c
--- /dev/null
+++ b/ui/views/controls/resize_area_unittest.cc
@@ -0,0 +1,200 @@
+// 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 "ui/views/controls/resize_area.h"
+
+#include <memory>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/aura/window.h"
+#include "ui/events/test/event_generator.h"
+#include "ui/views/controls/resize_area_delegate.h"
+#include "ui/views/test/views_test_base.h"
+#include "ui/views/view.h"
+#include "ui/views/widget/widget.h"
+
+namespace {
+// Constants used by the ResizeAreaTest.SuccessfulGestureDrag test to simulate
+// a gesture drag by |kGestureScrollDistance| resulting from
+// |kGestureScrollSteps| ui::ET_GESTURE_SCROLL_UPDATE events being delivered.
+const int kGestureScrollDistance = 100;
+const int kGestureScrollSteps = 4;
+const int kDistancePerGestureScrollUpdate =
+    kGestureScrollDistance / kGestureScrollSteps;
+}
+
+namespace views {
+
+// Testing delegate used by ResizeAreaTest.
+class TestResizeAreaDelegate : public ResizeAreaDelegate {
+ public:
+  TestResizeAreaDelegate();
+  ~TestResizeAreaDelegate() override;
+
+  // ResizeAreaDelegate:
+  void OnResize(int resize_amount, bool done_resizing) override;
+
+  int resize_amount() { return resize_amount_; }
+  bool done_resizing() { return done_resizing_; }
+  bool on_resize_called() { return on_resize_called_; }
+
+ private:
+  int resize_amount_;
+  bool done_resizing_;
+  bool on_resize_called_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestResizeAreaDelegate);
+};
+
+TestResizeAreaDelegate::TestResizeAreaDelegate()
+    : resize_amount_(0), done_resizing_(false), on_resize_called_(false) {}
+
+TestResizeAreaDelegate::~TestResizeAreaDelegate() {}
+
+void TestResizeAreaDelegate::OnResize(int resize_amount, bool done_resizing) {
+  resize_amount_ = resize_amount;
+  done_resizing_ = done_resizing;
+  on_resize_called_ = true;
+}
+
+// Test fixture for testing the ResizeArea class.
+class ResizeAreaTest : public ViewsTestBase {
+ public:
+  ResizeAreaTest();
+  ~ResizeAreaTest() override;
+
+  // Callback used by the SuccessfulGestureDrag test.
+  void ProcessGesture(ui::EventType type, const gfx::Vector2dF& delta);
+
+ protected:
+  // testing::Test:
+  void SetUp() override;
+  void TearDown() override;
+
+  ui::test::EventGenerator* event_generator() { return event_generator_.get(); }
+
+  int resize_amount() { return delegate_->resize_amount(); }
+  bool done_resizing() { return delegate_->done_resizing(); }
+  bool on_resize_called() { return delegate_->on_resize_called(); }
+  views::Widget* widget() { return widget_; }
+
+ private:
+  TestResizeAreaDelegate* delegate_ = nullptr;
+  ResizeArea* resize_area_ = nullptr;
+  views::Widget* widget_ = nullptr;
+  std::unique_ptr<ui::test::EventGenerator> event_generator_;
+
+  // The number of ui::ET_GESTURE_SCROLL_UPDATE events seen by
+  // ProcessGesture().
+  int gesture_scroll_updates_seen_ = 0;
+
+  DISALLOW_COPY_AND_ASSIGN(ResizeAreaTest);
+};
+
+ResizeAreaTest::ResizeAreaTest() {}
+
+ResizeAreaTest::~ResizeAreaTest() {}
+
+void ResizeAreaTest::ProcessGesture(ui::EventType type,
+                                    const gfx::Vector2dF& delta) {
+  if (type == ui::ET_GESTURE_SCROLL_BEGIN) {
+    EXPECT_FALSE(done_resizing());
+    EXPECT_FALSE(on_resize_called());
+  } else if (type == ui::ET_GESTURE_SCROLL_UPDATE) {
+    gesture_scroll_updates_seen_++;
+    EXPECT_EQ(kDistancePerGestureScrollUpdate * gesture_scroll_updates_seen_,
+              resize_amount());
+    EXPECT_FALSE(done_resizing());
+    EXPECT_TRUE(on_resize_called());
+  } else if (type == ui::ET_GESTURE_SCROLL_END) {
+    EXPECT_TRUE(done_resizing());
+  }
+}
+
+void ResizeAreaTest::SetUp() {
+  views::ViewsTestBase::SetUp();
+
+  delegate_ = new TestResizeAreaDelegate;
+  resize_area_ = new ResizeArea(delegate_);
+
+  gfx::Size size(10, 10);
+  resize_area_->SetBounds(0, 0, size.width(), size.height());
+
+  views::Widget::InitParams init_params(
+      CreateParams(views::Widget::InitParams::TYPE_WINDOW_FRAMELESS));
+  init_params.bounds = gfx::Rect(size);
+
+  widget_ = new views::Widget();
+  widget_->Init(init_params);
+  widget_->SetContentsView(resize_area_);
+  widget_->Show();
+
+  event_generator_.reset(
+      new ui::test::EventGenerator(widget_->GetNativeWindow()));
+}
+
+void ResizeAreaTest::TearDown() {
+  if (widget_ && !widget_->IsClosed())
+    widget_->Close();
+
+  views::ViewsTestBase::TearDown();
+}
+
+// TODO(tdanderson): Enable these tests on OSX. See crbug.com/710475.
+#if !defined(OS_MACOSX)
+// Verifies the correct calls have been made to
+// TestResizeAreaDelegate::OnResize() for a sequence of mouse events
+// corresponding to a successful resize operation.
+TEST_F(ResizeAreaTest, SuccessfulMouseDrag) {
+  event_generator()->MoveMouseToCenterOf(widget()->GetNativeView());
+  event_generator()->PressLeftButton();
+
+  const int kFirstDragAmount = -5;
+  event_generator()->MoveMouseBy(kFirstDragAmount, 0);
+  EXPECT_EQ(kFirstDragAmount, resize_amount());
+  EXPECT_FALSE(done_resizing());
+  EXPECT_TRUE(on_resize_called());
+
+  const int kSecondDragAmount = 17;
+  event_generator()->MoveMouseBy(kSecondDragAmount, 0);
+  EXPECT_EQ(kFirstDragAmount + kSecondDragAmount, resize_amount());
+  EXPECT_FALSE(done_resizing());
+
+  event_generator()->ReleaseLeftButton();
+  EXPECT_EQ(kFirstDragAmount + kSecondDragAmount, resize_amount());
+  EXPECT_TRUE(done_resizing());
+}
+
+// Verifies that no resize is performed when attempting to resize using the
+// right mouse button.
+TEST_F(ResizeAreaTest, FailedMouseDrag) {
+  event_generator()->MoveMouseToCenterOf(widget()->GetNativeView());
+  event_generator()->PressRightButton();
+
+  const int kDragAmount = 18;
+  event_generator()->MoveMouseBy(kDragAmount, 0);
+  EXPECT_EQ(0, resize_amount());
+}
+
+// Verifies the correct calls have been made to
+// TestResizeAreaDelegate::OnResize() for a sequence of gesture events
+// corresponding to a successful resize operation.
+TEST_F(ResizeAreaTest, SuccessfulGestureDrag) {
+  gfx::Point start = widget()->GetNativeView()->bounds().CenterPoint();
+  event_generator()->GestureScrollSequenceWithCallback(
+      start, gfx::Point(start.x() + kGestureScrollDistance, start.y()),
+      base::TimeDelta::FromMilliseconds(200), kGestureScrollSteps,
+      base::Bind(&ResizeAreaTest::ProcessGesture, base::Unretained(this)));
+}
+
+// Verifies that no resize is performed on a gesture tap.
+TEST_F(ResizeAreaTest, NoDragOnGestureTap) {
+  event_generator()->GestureTapAt(
+      widget()->GetNativeView()->bounds().CenterPoint());
+
+  EXPECT_EQ(0, resize_amount());
+}
+#endif  // !defined(OS_MACOSX)
+
+}  // namespace views