Implement CSS: scroll-boundary-behavior

cc/trees/layer_tree_host_impl_unittest.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host_impl.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 1407 matching lines @@
           ->ScrollBy(UpdateState(gfx::Point(), gfx::Vector2d(-10, 10)).get())
           .did_scroll);
 
   // Trying to scroll more than the available space will also succeed.
   EXPECT_TRUE(
       host_impl_
           ->ScrollBy(UpdateState(gfx::Point(), gfx::Vector2d(5000, 5000)).get())
           .did_scroll);
 }
 
+TEST_F(LayerTreeHostImplTest, ScrollBoundaryBehaviorPreventsPropagation) {
+  LayerImpl* scroll_layer = SetupScrollAndContentsLayers(gfx::Size(200, 200));
+  host_impl_->SetViewportSize(gfx::Size(100, 100));
+
+  gfx::Size overflow_size(400, 400);
+  ASSERT_EQ(1u, scroll_layer->test_properties()->children.size());
+  LayerImpl* overflow = scroll_layer->test_properties()->children[0];
+  overflow->SetBounds(overflow_size);
+  overflow->SetScrollable(gfx::Size(100, 100));
+  overflow->SetElementId(LayerIdToElementIdForTesting(overflow->id()));
+  overflow->layer_tree_impl()
+      ->property_trees()
+      ->scroll_tree.UpdateScrollOffsetBaseForTesting(overflow->element_id(),
+                                                     gfx::ScrollOffset());
+  overflow->SetPosition(gfx::PointF(40, 40));
+  host_impl_->active_tree()->BuildPropertyTreesForTesting();
+  scroll_layer->SetCurrentScrollOffset(gfx::ScrollOffset(30, 30));
+
+  DrawFrame();
+  gfx::Point scroll_position(50, 50);
+
+  // ScrollBoundaryBehaviorTypeAuto shouldn't prevent scroll propagation.
+  EXPECT_EQ(
+      InputHandler::SCROLL_ON_IMPL_THREAD,
+      host_impl_
+          ->ScrollBegin(BeginState(scroll_position).get(), InputHandler::WHEEL)
+          .thread);
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(30, 30), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(), overflow->CurrentScrollOffset());
+
+  gfx::Vector2dF x_dominant_delta(-10, -5);
+  gfx::Vector2dF y_dominant_delta(-5, -10);
+  host_impl_->ScrollBy(UpdateState(scroll_position, x_dominant_delta).get());
+  host_impl_->ScrollEnd(EndState().get());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(20, 25), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  overflow->test_properties()->scroll_boundary_behavior =
+      ScrollBoundaryBehavior(
+          ScrollBoundaryBehavior::kScrollBoundaryBehaviorTypeNone,
+          ScrollBoundaryBehavior::kScrollBoundaryBehaviorTypeAuto);
+  host_impl_->active_tree()->BuildPropertyTreesForTesting();
+
+  DrawFrame();
+
+  // ScrollBoundaryBehaviorNone on x should prevent x-dominant-scroll
+  // propagation.
+  EXPECT_EQ(
+      InputHandler::SCROLL_ON_IMPL_THREAD,
+      host_impl_
+          ->ScrollBegin(BeginState(scroll_position).get(), InputHandler::WHEEL)
+          .thread);
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(20, 25), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  host_impl_->ScrollBy(UpdateState(scroll_position, x_dominant_delta).get());
+  host_impl_->ScrollEnd(EndState().get());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(20, 25), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  // ScrollBoundaryBehaviorNone on x shouldn't prevent y-dominant-scroll
+  // propagation.
+  EXPECT_EQ(
+      InputHandler::SCROLL_ON_IMPL_THREAD,
+      host_impl_
+          ->ScrollBegin(BeginState(scroll_position).get(), InputHandler::WHEEL)
+          .thread);
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(20, 25), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  host_impl_->ScrollBy(UpdateState(scroll_position, y_dominant_delta).get());
+  host_impl_->ScrollEnd(EndState().get());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(15, 15), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  overflow->test_properties()->scroll_boundary_behavior =
+      ScrollBoundaryBehavior(
+          ScrollBoundaryBehavior::kScrollBoundaryBehaviorTypeAuto,
+          ScrollBoundaryBehavior::kScrollBoundaryBehaviorTypeNone);
+  host_impl_->active_tree()->BuildPropertyTreesForTesting();
+
+  DrawFrame();
+
+  // ScrollBoundaryBehaviorNone on y shouldn't prevent x-dominant-scroll
+  // propagation.
+  EXPECT_EQ(
+      InputHandler::SCROLL_ON_IMPL_THREAD,
+      host_impl_
+          ->ScrollBegin(BeginState(scroll_position).get(), InputHandler::WHEEL)
+          .thread);
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(15, 15), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  host_impl_->ScrollBy(UpdateState(scroll_position, x_dominant_delta).get());
+  host_impl_->ScrollEnd(EndState().get());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(5, 10), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  // ScrollBoundaryBehaviorNone on y should prevent y-dominant-scroll
+  // propagation.
+  EXPECT_EQ(
+      InputHandler::SCROLL_ON_IMPL_THREAD,
+      host_impl_
+          ->ScrollBegin(BeginState(scroll_position).get(), InputHandler::WHEEL)
+          .thread);
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(5, 10), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+
+  host_impl_->ScrollBy(UpdateState(scroll_position, y_dominant_delta).get());
+  host_impl_->ScrollEnd(EndState().get());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(5, 10), scroll_layer->CurrentScrollOffset());
+  EXPECT_VECTOR_EQ(gfx::Vector2dF(0, 0), overflow->CurrentScrollOffset());
+}
+
 TEST_F(LayerTreeHostImplTest, ScrollWithUserUnscrollableLayers) {
   LayerImpl* scroll_layer = SetupScrollAndContentsLayers(gfx::Size(200, 200));
   host_impl_->SetViewportSize(gfx::Size(100, 100));
 
   gfx::Size overflow_size(400, 400);
   ASSERT_EQ(1u, scroll_layer->test_properties()->children.size());
   LayerImpl* overflow = scroll_layer->test_properties()->children[0];
   overflow->SetBounds(overflow_size);
   overflow->SetScrollable(gfx::Size(100, 100));
   overflow->SetElementId(LayerIdToElementIdForTesting(overflow->id()));
@@ skipping 11221 matching lines @@
   // layer should be prioritized over the hidden layer.
   hidden_layer->set_contributes_to_drawn_render_surface(false);
   hidden_layer->set_raster_even_if_not_drawn(true);
   queue = host_impl_->BuildRasterQueue(TreePriority::SMOOTHNESS_TAKES_PRIORITY,
                                        RasterTilePriorityQueue::Type::ALL);
   EXPECT_EQ(queue->Top().tile()->layer_id(), 3);
 }
 
 }  // namespace
 }  // namespace cc