Touch Events - changedTouches list includes non-changed touch points on Android

content/browser/renderer_host/input/touch_event_queue_unittest.cc

Index: content/browser/renderer_host/input/touch_event_queue_unittest.cc
diff --git a/content/browser/renderer_host/input/touch_event_queue_unittest.cc b/content/browser/renderer_host/input/touch_event_queue_unittest.cc
index fcd5ce8d07b4ba1c8b25408d73129788b71e3e5f..6f9a273576125ebd0a5c70f6b0b8049878d94b2b 100644
--- a/content/browser/renderer_host/input/touch_event_queue_unittest.cc
+++ b/content/browser/renderer_host/input/touch_event_queue_unittest.cc
@@ -1935,7 +1935,7 @@ TEST_F(TouchEventQueueTest, AsyncTouchThrottledAfterScroll) {
   EXPECT_TRUE(sent_event().cancelable);
   EXPECT_FALSE(HasPendingAsyncTouchMove());
   EXPECT_EQ(WebInputEvent::TouchMove, sent_event().type);
-  EXPECT_EQ(WebTouchPoint::StateMoved, sent_event().touches[0].state);
+  EXPECT_EQ(WebTouchPoint::StateStationary, sent_event().touches[0].state);
   EXPECT_EQ(WebTouchPoint::StateMoved, sent_event().touches[1].state);
   EXPECT_EQ(1U, queued_event_count());
   EXPECT_EQ(1U, GetAndResetSentEventCount());
@@ -2225,4 +2225,60 @@ TEST_F(TouchEventQueueTest, UnseenTouchPointerIdsNotForwarded) {
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
 }
 
+// Tests that touches state is correct in TouchMove events.
+TEST_F(TouchEventQueueTest, TouchMoveTouchesState) {
+  PressTouchPoint(1, 1);
+  PressTouchPoint(2, 2);
+  PressTouchPoint(3, 3);
+  PressTouchPoint(4, 4);
+  EXPECT_EQ(4U, queued_event_count());
+  EXPECT_EQ(1U, GetAndResetSentEventCount());
+
+  // Receive ACK for the first three touch-events
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_CONSUMED);
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_CONSUMED);
+  EXPECT_EQ(1U, queued_event_count());
+
+  // Test current touches state before sending TouchMoves
+  const WebTouchEvent& event1 = sent_event();
+  EXPECT_EQ(WebInputEvent::TouchStart, event1.type);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event1.touches[0].state);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event1.touches[1].state);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event1.touches[2].state);
+  EXPECT_EQ(WebTouchPoint::StatePressed, event1.touches[3].state);
+
+  // Move x-position for 1st touch, y-position for 2nd touch
+  // and do not move other touches.
+  MoveTouchPoints(0, 1.1, 1, 1, 2, 20.001);
+  MoveTouchPoints(2, 3, 3, 3, 4, 4);

[jdduke (slow), 2015/01/06 17:57:29]

I would just remove "MoveTouchPoints(2, 3, 3, 3, 4, 4);".

[USE s.singapati at gmail.com, 2015/01/07 16:08:39]

Actually for unit tests, with SyntheticWebTouchEvent::MovePoint()
implementation, only those explicitly specified touches would have state as
"WebTouchPoint::StateMoved", otherwise no change in state of touches. This
behavior is different in CreateWebTouchPoint() in web_input_event_util.cc. SO,
to reproduce the ORIGINAL problem with unit tests we need to call MovePoint()
for all touches.

[jdduke (slow), 2015/01/07 16:14:31]

I see, that's unfortunate but probably not worth the trouble of addressing now,
thanks for the explanation.

+  EXPECT_EQ(2U, queued_event_count());
+
+  // Receive an ACK for the last TouchPress event

[jdduke (slow), 2015/01/06 17:57:29]

Why defer this ack? It's confusing to perform it here instead of above with the
other press acks.

[USE s.singapati at gmail.com, 2015/01/07 16:08:39]

Continuing from above comment, those 4 Touchmoves need to be potentially
coalesced and sent as one TouchMove.

+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_CONSUMED);
+
+  // 1st TouchMove is sent. Test for touches state.
+  const WebTouchEvent& event2 = sent_event();
+  EXPECT_EQ(WebInputEvent::TouchMove, event2.type);
+  EXPECT_EQ(WebTouchPoint::StateMoved, event2.touches[0].state);
+  EXPECT_EQ(WebTouchPoint::StateMoved, event2.touches[1].state);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event2.touches[2].state);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event2.touches[3].state);
+
+  // Move only 4th touch but not others.
+  MoveTouchPoints(0, 1.1, 1, 1, 2, 20.001);

[jdduke (slow), 2015/01/06 17:57:29]

Why move all of them? Just do

MoveTouchPoint(3, 4.1, 4.1);

[USE s.singapati at gmail.com, 2015/01/07 16:08:39]

Same as 1st comment.

+  MoveTouchPoints(2, 3, 3, 3, 4.1, 4.1);
+
+  // Receive an ACK for previous (1st) TouchMove
+  SendTouchEventAck(INPUT_EVENT_ACK_STATE_CONSUMED);
+
+  // 2nd TouchMove is sent. Test for touches state.
+  const WebTouchEvent& event3 = sent_event();
+  EXPECT_EQ(WebInputEvent::TouchMove, event3.type);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event3.touches[0].state);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event3.touches[1].state);
+  EXPECT_EQ(WebTouchPoint::StateStationary, event3.touches[2].state);
+  EXPECT_EQ(WebTouchPoint::StateMoved, event3.touches[3].state);
+}
+
 }  // namespace content