Support longpress drag selection

ui/touch_selection/longpress_drag_selector_unittest.cc

Index: ui/touch_selection/longpress_drag_selector_unittest.cc
diff --git a/ui/touch_selection/longpress_drag_selector_unittest.cc b/ui/touch_selection/longpress_drag_selector_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..1721d690a2b69dc0689490963f7de36037b1504d
--- /dev/null
+++ b/ui/touch_selection/longpress_drag_selector_unittest.cc
@@ -0,0 +1,332 @@
+// Copyright 2014 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/touch_selection/longpress_drag_selector.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/events/test/motion_event_test_utils.h"
+
+using ui::test::MockMotionEvent;
+
+namespace ui {
+namespace {
+
+const double kSlop = 10.;
+
+}  // namespace
+
+class LongPressDragSelectorTest : public testing::Test,
+                                  public LongPressDragSelectorClient {
+ public:
+  LongPressDragSelectorTest()
+      : dragging_(false), active_state_changed_(false) {}
+
+  ~LongPressDragSelectorTest() override {}
+
+  // LongPressDragSelectorClient implementation.

[mfomitchev, 2015/05/13 20:52:25]

Can we put the LongPressDragSelectorClient methods at the end? Otherwise it's
harder to tell which ones are from LongPressDragSelectorClient and which ones
aren't.

[jdduke (slow), 2015/05/14 18:29:26]

Done.

+  void OnDragBegin(const TouchSelectionDraggable& handler,
+                   const gfx::PointF& drag_position) override {
+    dragging_ = true;
+    drag_position_ = drag_position;
+  }
+
+  void OnDragUpdate(const TouchSelectionDraggable& handler,
+                    const gfx::PointF& drag_position) override {
+    drag_position_ = drag_position;
+  }
+
+  void OnDragEnd(const TouchSelectionDraggable& handler) override {
+    dragging_ = false;
+  }
+
+  bool IsWithinTapSlop(const gfx::Vector2dF& delta) const override {
+    return delta.LengthSquared() < (kSlop * kSlop);
+  }
+
+  void OnLongPressDragActiveStateChanged() override {
+    active_state_changed_ = true;
+  }
+
+  gfx::PointF GetSelectionStart() const override { return selection_start_; }
+
+  gfx::PointF GetSelectionEnd() const override { return selection_end_; }
+
+  void SetSelection(const gfx::PointF& start, const gfx::PointF& end) {
+    selection_start_ = start;
+    selection_end_ = end;
+  }
+
+  bool GetAndResetActiveStateChanged() {
+    bool active_state_changed = active_state_changed_;
+    active_state_changed_ = false;
+    return active_state_changed;
+  }
+
+  bool IsDragging() const { return dragging_; }
+  const gfx::PointF& DragPosition() const { return drag_position_; }
+
+ private:
+  bool dragging_;
+  bool active_state_changed_;
+  gfx::PointF drag_position_;
+
+  gfx::PointF selection_start_;
+  gfx::PointF selection_end_;
+};
+
+TEST_F(LongPressDragSelectorTest, BasicDrag) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Start a touch sequence.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+
+  // Activate a longpress-triggered selection.
+  gfx::PointF selection_start(0, 10);
+  gfx::PointF selection_end(10, 10);
+  selector.OnLongPressEvent(event.GetEventTime(), gfx::PointF());
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+
+  // Motion should not be consumed until a selection is detected.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  SetSelection(selection_start, selection_end);
+  selector.OnSelectionActivated();
+  EXPECT_FALSE(IsDragging());
+
+  // Initiate drag motion. The motion is downward, so the end selection point

[mfomitchev, 2015/05/13 20:52:25]

The comment about downward motion would probably fit better with the non-zero
move below.

[jdduke (slow), 2015/05/14 18:29:26]

Done.

+  // should be moved. Note that the first move event after activation is used to
+  // initialize the drag start anchor.
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_FALSE(IsDragging());
+
+  // The first slop exceeding motion will start the drag.
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop)));
+  EXPECT_TRUE(IsDragging());
+  EXPECT_EQ(selection_end, DragPosition());
+
+  // Subsequent motion will extend the selection.
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 2)));
+  EXPECT_TRUE(IsDragging());
+  EXPECT_EQ(selection_end + gfx::Vector2dF(0, kSlop), DragPosition());
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 3)));
+  EXPECT_TRUE(IsDragging());
+  EXPECT_EQ(selection_end + gfx::Vector2dF(0, kSlop * 2), DragPosition());
+
+  // Release the touch sequence, ending the drag. The selector will never
+  // consume the start/end events, only move events after a longpress.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.ReleasePoint()));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+}
+
+TEST_F(LongPressDragSelectorTest, BasicReverseDrag) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Start a touch sequence.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+
+  // Activate a longpress-triggered selection.
+  gfx::PointF selection_start(0, 10);
+  gfx::PointF selection_end(10, 10);
+  selector.OnLongPressEvent(event.GetEventTime(), gfx::PointF());
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+  SetSelection(selection_start, selection_end);
+  selector.OnSelectionActivated();
+  EXPECT_FALSE(IsDragging());
+
+  // Initiate drag motion. The initial motion is leftward, toward the selection
+  // start, so that should be the drag point.
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, kSlop, 0)));

[mfomitchev, 2015/05/13 20:52:25]

I don't get it - kSlop is greater than 0, so why is the motion leftward, not
rightward? Or is this just establishing the starting point even though we've had
the PressPoint @ (0, 0)?

[jdduke (slow), 2015/05/14 18:29:26]

Yeah, the comment is in a bad position, I'll change it.

+  EXPECT_FALSE(IsDragging());
+
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_TRUE(IsDragging());
+  EXPECT_EQ(selection_start, DragPosition());
+
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, -kSlop)));
+  EXPECT_TRUE(IsDragging());
+  EXPECT_EQ(selection_start + gfx::Vector2dF(0, -kSlop), DragPosition());
+
+  // Release the touch sequence, ending the drag.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.ReleasePoint()));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+}
+
+TEST_F(LongPressDragSelectorTest, NoActiveTouch) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Activate a longpress-triggered selection.
+  gfx::PointF selection_start(0, 10);
+  gfx::PointF selection_end(10, 10);
+  selector.OnLongPressEvent(event.GetEventTime(), gfx::PointF());
+  SetSelection(selection_start, selection_end);
+  selector.OnSelectionActivated();
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+  EXPECT_FALSE(IsDragging());
+
+  // Start a new touch sequence; it shouldn't initiate selection drag as there
+  // was no active touch sequence when the longpress selection started.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 2)));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_EQ(gfx::PointF(), DragPosition());
+}
+
+TEST_F(LongPressDragSelectorTest, NoLongPress) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Start a touch sequence.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+
+  // Activate a selection without a preceding longpress.
+  gfx::PointF selection_start(0, 10);
+  gfx::PointF selection_end(10, 10);
+  SetSelection(selection_start, selection_end);
+  selector.OnSelectionActivated();
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+  EXPECT_FALSE(IsDragging());
+
+  // Touch movement should not initiate selection drag.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 2)));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_EQ(gfx::PointF(), DragPosition());
+}
+
+TEST_F(LongPressDragSelectorTest, NoValidLongPress) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Start a touch sequence.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+
+  gfx::PointF selection_start(0, 10);
+  gfx::PointF selection_end(10, 10);
+  SetSelection(selection_start, selection_end);
+
+  // Activate a longpress-triggered selection, but at a time different than the

[mfomitchev, 2015/05/13 20:52:25]

different -> before ?

[jdduke (slow), 2015/05/14 18:29:26]

Done.

+  // current touch down event.
+  selector.OnLongPressEvent(
+      event.GetEventTime() - base::TimeDelta::FromSeconds(1), gfx::PointF());
+  selector.OnSelectionActivated();
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+  EXPECT_FALSE(IsDragging());
+
+  // Activate a longpress-triggered selection, but at a place different than the
+  // current touch down event.
+  selector.OnLongPressEvent(event.GetEventTime(), gfx::PointF(kSlop * 2, 0));

[mfomitchev, 2015/05/13 20:52:25]

Can we do kSlop here instead of kSlop * 2?

[jdduke (slow), 2015/05/14 18:29:26]

Done.

+  selector.OnSelectionActivated();
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+  EXPECT_FALSE(IsDragging());
+
+  // Touch movement should not initiate selection drag.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 2)));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_EQ(gfx::PointF(), DragPosition());
+}
+
+TEST_F(LongPressDragSelectorTest, NoSelection) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Start a touch sequence.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+
+  // Trigger a longpress. This will notify the client that detection is active,
+  // but until there's a longpress no drag selection should occur.
+  selector.OnLongPressEvent(event.GetEventTime(), gfx::PointF());
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+  EXPECT_FALSE(IsDragging());
+
+  // Touch movement should not initiate selection drag, as there is no active
+  // selection.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 2)));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_EQ(gfx::PointF(), DragPosition());
+
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.ReleasePoint()));
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+}
+
+TEST_F(LongPressDragSelectorTest, NoDragMotion) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Start a touch sequence.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+
+  // Activate a longpress-triggered selection.
+  selector.OnLongPressEvent(event.GetEventTime(), gfx::PointF());
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+  gfx::PointF selection_start(0, 10);
+  gfx::PointF selection_end(10, 10);
+  SetSelection(selection_start, selection_end);
+  selector.OnSelectionActivated();
+  EXPECT_FALSE(IsDragging());
+
+  // Touch movement within the slop region should not initiate selection drag.
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop / 2)));
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, -kSlop / 2)));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_EQ(gfx::PointF(), DragPosition());
+
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.ReleasePoint()));
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+}
+
+TEST_F(LongPressDragSelectorTest, SelectionDeactivated) {
+  LongPressDragSelector selector(this);
+  MockMotionEvent event;
+
+  // Start a touch sequence.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.PressPoint(0, 0)));
+  EXPECT_FALSE(GetAndResetActiveStateChanged());
+
+  // Activate a longpress-triggered selection.
+  selector.OnLongPressEvent(event.GetEventTime(), gfx::PointF());
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+  gfx::PointF selection_start(0, 10);
+  gfx::PointF selection_end(10, 10);
+  SetSelection(selection_start, selection_end);
+  selector.OnSelectionActivated();
+  EXPECT_FALSE(IsDragging());
+
+  // Start a drag selection.
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop)));
+  EXPECT_TRUE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 2)));
+  EXPECT_TRUE(IsDragging());
+
+  // Clearing the selection should force an end to the drag.
+  selector.OnSelectionDeactivated();
+  EXPECT_TRUE(GetAndResetActiveStateChanged());
+  EXPECT_FALSE(IsDragging());
+
+  // Subsequent motion should not be consumed.
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, 0)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop)));
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.MovePoint(0, 0, kSlop * 2)));
+  EXPECT_FALSE(IsDragging());
+  EXPECT_FALSE(selector.WillHandleTouchEvent(event.ReleasePoint()));
+}
+
+}  // namespace ui