Touchpad scroll latching enabled for Mac behind flag.

content/browser/renderer_host/input/mouse_wheel_event_queue_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 "content/browser/renderer_host/input/mouse_wheel_event_queue.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <utility>
@@ skipping 300 matching lines @@
     const WebGestureEvent::ScrollUnits scroll_units =
         high_precision ? WebGestureEvent::PrecisePixels
                        : WebGestureEvent::Pixels;
 
     SendMouseWheelWithPhase(kWheelScrollX, kWheelScrollY, kWheelScrollGlobalX,
                             kWheelScrollGlobalY, 1, 1, 0, high_precision,
                             WebMouseWheelEvent::PhaseBegan,
                             WebMouseWheelEvent::PhaseNone);
     EXPECT_EQ(1U, GetAndResetSentEventCount());
     SendMouseWheelEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
-    EXPECT_EQ(3U, all_sent_events().size());
-    EXPECT_GESTURE_SCROLL_BEGIN_WITH_PHASE(sent_gesture_event(0));
-    EXPECT_GESTURE_SCROLL_UPDATE_WITH_PHASE(sent_gesture_event(1));
-    EXPECT_SYNTHETIC_GESTURE_SCROLL_END(sent_gesture_event(2));
-    EXPECT_EQ(3U, GetAndResetSentEventCount());
+    if (scroll_latching_enabled_) {
+      EXPECT_EQ(2U, all_sent_events().size());
+      EXPECT_GESTURE_SCROLL_BEGIN_WITH_PHASE(sent_gesture_event(0));
+      EXPECT_GESTURE_SCROLL_UPDATE_WITH_PHASE(sent_gesture_event(1));
+      EXPECT_EQ(2U, GetAndResetSentEventCount());
+    } else {
+      EXPECT_EQ(3U, all_sent_events().size());
+      EXPECT_GESTURE_SCROLL_BEGIN_WITH_PHASE(sent_gesture_event(0));
+      EXPECT_GESTURE_SCROLL_UPDATE_WITH_PHASE(sent_gesture_event(1));
+      EXPECT_SYNTHETIC_GESTURE_SCROLL_END(sent_gesture_event(2));
+      EXPECT_EQ(3U, GetAndResetSentEventCount());
+    }
 
     SendMouseWheelWithPhase(kWheelScrollX, kWheelScrollY, kWheelScrollGlobalX,
                             kWheelScrollGlobalY, 5, 5, 0, high_precision,
                             WebMouseWheelEvent::PhaseChanged,
                             WebMouseWheelEvent::PhaseNone);
     EXPECT_EQ(1U, GetAndResetSentEventCount());
     SendMouseWheelEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
-    EXPECT_EQ(3U, all_sent_events().size());
-    EXPECT_SYNTHETIC_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
-    EXPECT_GESTURE_SCROLL_UPDATE_WITH_PHASE(sent_gesture_event(1));
-    EXPECT_SYNTHETIC_GESTURE_SCROLL_END(sent_gesture_event(2));
-    EXPECT_EQ(3U, GetAndResetSentEventCount());
+    if (scroll_latching_enabled_) {
+      EXPECT_EQ(1U, all_sent_events().size());
+      EXPECT_GESTURE_SCROLL_UPDATE_WITH_PHASE(sent_gesture_event(0));
+      EXPECT_EQ(1U, GetAndResetSentEventCount());
+    } else {
+      EXPECT_EQ(3U, all_sent_events().size());
+      EXPECT_SYNTHETIC_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
+      EXPECT_GESTURE_SCROLL_UPDATE_WITH_PHASE(sent_gesture_event(1));
+      EXPECT_SYNTHETIC_GESTURE_SCROLL_END(sent_gesture_event(2));
+      EXPECT_EQ(3U, GetAndResetSentEventCount());
+    }
 
     SendMouseWheelWithPhase(kWheelScrollX, kWheelScrollY, kWheelScrollGlobalX,
                             kWheelScrollGlobalY, 0, 0, 0, high_precision,
                             WebMouseWheelEvent::PhaseEnded,
                             WebMouseWheelEvent::PhaseNone);
     EXPECT_EQ(1U, GetAndResetSentEventCount());
     SendMouseWheelEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
-    EXPECT_EQ(2U, all_sent_events().size());
-    EXPECT_SYNTHETIC_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
-    EXPECT_GESTURE_SCROLL_END_WITH_PHASE(sent_gesture_event(1));
-    EXPECT_EQ(2U, GetAndResetSentEventCount());
+    if (scroll_latching_enabled_) {
+      // ScrollEnd is not sent right away, a timer starts instead,
+      // to see if a wheel event with momentumPhase arrives or not.
+      EXPECT_EQ(0U, all_sent_events().size());
+      EXPECT_EQ(0U, GetAndResetSentEventCount());
+    } else {
+      EXPECT_EQ(2U, all_sent_events().size());
+      EXPECT_SYNTHETIC_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
+      EXPECT_GESTURE_SCROLL_END_WITH_PHASE(sent_gesture_event(1));
+      EXPECT_EQ(2U, GetAndResetSentEventCount());
+    }
 
     // Send a double phase end; OSX does it consistently.
     SendMouseWheelWithPhase(kWheelScrollX, kWheelScrollY, kWheelScrollGlobalX,
                             kWheelScrollGlobalY, 0, 0, 0, high_precision,
                             WebMouseWheelEvent::PhaseEnded,
                             WebMouseWheelEvent::PhaseNone);
     EXPECT_EQ(1U, GetAndResetSentEventCount());
     SendMouseWheelEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
     EXPECT_EQ(0U, all_sent_events().size());
     EXPECT_EQ(0U, GetAndResetSentEventCount());
 
     SendMouseWheelWithPhase(kWheelScrollX, kWheelScrollY, kWheelScrollGlobalX,
                             kWheelScrollGlobalY, 5, 5, 0, high_precision,
                             WebMouseWheelEvent::PhaseNone,
                             WebMouseWheelEvent::PhaseBegan);
     EXPECT_EQ(1U, GetAndResetSentEventCount());
     SendMouseWheelEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
-    EXPECT_EQ(3U, all_sent_events().size());
-    EXPECT_INERTIAL_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
-    EXPECT_INERTIAL_GESTURE_SCROLL_UPDATE(sent_gesture_event(1));
-    EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_END(sent_gesture_event(2));
-    EXPECT_EQ(3U, GetAndResetSentEventCount());
+    if (scroll_latching_enabled_) {
+      // A fling has started, no ScrollEnd/ScrollBegin is sent.
+      EXPECT_EQ(1U, all_sent_events().size());
+      EXPECT_INERTIAL_GESTURE_SCROLL_UPDATE(sent_gesture_event(0));
+      EXPECT_EQ(1U, GetAndResetSentEventCount());
+    } else {
+      EXPECT_EQ(3U, all_sent_events().size());
+      EXPECT_INERTIAL_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
+      EXPECT_INERTIAL_GESTURE_SCROLL_UPDATE(sent_gesture_event(1));
+      EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_END(sent_gesture_event(2));
+      EXPECT_EQ(3U, GetAndResetSentEventCount());
+    }
 
     SendMouseWheelWithPhase(kWheelScrollX, kWheelScrollY, kWheelScrollGlobalX,
                             kWheelScrollGlobalY, 5, 5, 0, high_precision,
                             WebMouseWheelEvent::PhaseNone,
                             WebMouseWheelEvent::PhaseChanged);
     EXPECT_EQ(1U, GetAndResetSentEventCount());
     SendMouseWheelEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
-    EXPECT_EQ(3U, all_sent_events().size());
-    EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
-    EXPECT_INERTIAL_GESTURE_SCROLL_UPDATE(sent_gesture_event(1));
-    EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_END(sent_gesture_event(2));
-    EXPECT_EQ(3U, GetAndResetSentEventCount());
+    if (scroll_latching_enabled_) {
+      EXPECT_EQ(1U, all_sent_events().size());
+      EXPECT_INERTIAL_GESTURE_SCROLL_UPDATE(sent_gesture_event(0));
+      EXPECT_EQ(1U, GetAndResetSentEventCount());
+    } else {
+      EXPECT_EQ(3U, all_sent_events().size());
+      EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
+      EXPECT_INERTIAL_GESTURE_SCROLL_UPDATE(sent_gesture_event(1));
+      EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_END(sent_gesture_event(2));
+      EXPECT_EQ(3U, GetAndResetSentEventCount());
+    }
 
     SendMouseWheelWithPhase(kWheelScrollX, kWheelScrollY, kWheelScrollGlobalX,
                             kWheelScrollGlobalY, 0, 0, 0, high_precision,
                             WebMouseWheelEvent::PhaseNone,
                             WebMouseWheelEvent::PhaseEnded);
     EXPECT_EQ(1U, GetAndResetSentEventCount());
     SendMouseWheelEventAck(INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
-    EXPECT_EQ(2U, all_sent_events().size());
-    EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
-    EXPECT_INERTIAL_GESTURE_SCROLL_END(sent_gesture_event(1));
-    EXPECT_EQ(2U, GetAndResetSentEventCount());
+    if (scroll_latching_enabled_) {
+      // MomentumPhase is ended, the scroll is done, and GSE is sent
+      // immediately.
+      EXPECT_EQ(1U, all_sent_events().size());
+      EXPECT_INERTIAL_GESTURE_SCROLL_END(sent_gesture_event(0));
+      EXPECT_EQ(1U, GetAndResetSentEventCount());
+    } else {
+      EXPECT_EQ(2U, all_sent_events().size());
+      EXPECT_SYNTHETIC_INERTIAL_GESTURE_SCROLL_BEGIN(sent_gesture_event(0));
+      EXPECT_INERTIAL_GESTURE_SCROLL_END(sent_gesture_event(1));
+      EXPECT_EQ(2U, GetAndResetSentEventCount());
+    }
   }
 
   std::unique_ptr<MouseWheelEventQueue> queue_;
   std::vector<std::unique_ptr<WebInputEvent>> sent_events_;
   size_t acked_event_count_;
   InputEventAckState last_acked_event_state_;
   base::MessageLoopForUI message_loop_;
   WebMouseWheelEvent last_acked_event_;
   int64_t scroll_end_timeout_ms_;
   bool scroll_latching_enabled_;
@@ skipping 29 matching lines @@
   EXPECT_EQ(0U, GetAndResetSentEventCount());
   EXPECT_EQ(1U, GetAndResetAckedEventCount());
   EXPECT_EQ(WebInputEvent::MouseWheel, acked_event().type);
 }
 
 TEST_P(MouseWheelEventQueueTest, GestureSending) {
   GestureSendingTest(false);
 }
 
 TEST_P(MouseWheelEventQueueTest, GestureSendingPrecisePixels) {
-  GestureSendingTest(false);
+  GestureSendingTest(true);
 }
 
 TEST_P(MouseWheelEventQueueTest, GestureSendingWithPhaseInformation) {
   PhaseGestureSendingTest(false);
 }
 
 TEST_P(MouseWheelEventQueueTest,
        GestureSendingWithPhaseInformationPrecisePixels) {
   PhaseGestureSendingTest(true);
 }
@@ skipping 168 matching lines @@
   EXPECT_EQ(1U, sent_gesture_event(updateEventIndex)->data.scrollUpdate.deltaY);
   EXPECT_EQ(static_cast<size_t>(updateEventIndex + 1),
             GetAndResetSentEventCount());
 }
 
 INSTANTIATE_TEST_CASE_P(MouseWheelEventQueueTests,
                         MouseWheelEventQueueTest,
                         testing::Bool());
 
 }  // namespace content