// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "cc/base/features.h"
#include "third_party/blink/renderer/core/dom/document.h"
#include "third_party/blink/renderer/core/frame/local_dom_window.h"
#include "third_party/blink/renderer/core/html/html_element.h"
#include "third_party/blink/renderer/core/input/event_handler.h"
#include "third_party/blink/renderer/core/input/scroll_manager.h"
#include "third_party/blink/renderer/core/layout/layout_box.h"
#include "third_party/blink/renderer/core/paint/paint_layer_scrollable_area.h"
#include "third_party/blink/renderer/core/style/computed_style.h"
#include "third_party/blink/renderer/core/testing/sim/sim_compositor.h"
#include "third_party/blink/renderer/core/testing/sim/sim_request.h"
#include "third_party/blink/renderer/core/testing/sim/sim_test.h"
namespace blink {
class ScrollSnapTest : public SimTest {
protected:
void SetUpForDiv();
// The following x, y, hint_x, hint_y, delta_x, delta_y are represents
// the pointer/finger's location on touch screen.
void GestureScroll(double x,
double y,
double delta_x,
double delta_y,
bool composited = false);
void ScrollBegin(double x, double y, double hint_x, double hint_y);
void ScrollUpdate(double x,
double y,
double delta_x,
double delta_y,
bool is_in_inertial_phase = false);
void ScrollEnd(double x, double y, bool is_in_inertial_phase = false);
void SetInitialScrollOffset(double x, double y);
};
void ScrollSnapTest::SetUpForDiv() {
v8::HandleScope HandleScope(
WebView().GetPage()->GetAgentGroupScheduler().Isolate());
WebView().MainFrameViewWidget()->Resize(gfx::Size(400, 400));
SimRequest request("https://example.com/test.html", "text/html");
LoadURL("https://example.com/test.html");
request.Complete(R"HTML(
)HTML");
Compositor().BeginFrame();
}
void ScrollSnapTest::GestureScroll(double x,
double y,
double delta_x,
double delta_y,
bool composited) {
ScrollBegin(x, y, delta_x, delta_y);
ScrollUpdate(x, y, delta_x, delta_y);
ScrollEnd(x + delta_x, y + delta_y);
// Wait for animation to finish.
// Pass raster = true to reach LayerTreeHostImpl::UpdateAnimationState,
// which will set start time and transition to KeyframeModel::RUNNING.
Compositor().BeginFrame(0.016, true);
Compositor().BeginFrame(0.3);
}
void ScrollSnapTest::ScrollBegin(double x,
double y,
double hint_x,
double hint_y) {
WebGestureEvent event(WebInputEvent::Type::kGestureScrollBegin,
WebInputEvent::kNoModifiers, base::TimeTicks::Now(),
WebGestureDevice::kTouchscreen);
event.SetPositionInWidget(gfx::PointF(x, y));
event.SetPositionInScreen(gfx::PointF(x, y));
event.data.scroll_begin.delta_x_hint = hint_x;
event.data.scroll_begin.delta_y_hint = hint_y;
event.data.scroll_begin.pointer_count = 1;
event.SetFrameScale(1);
GetWebFrameWidget().DispatchThroughCcInputHandler(event);
}
void ScrollSnapTest::ScrollUpdate(double x,
double y,
double delta_x,
double delta_y,
bool is_in_inertial_phase) {
WebGestureEvent event(WebInputEvent::Type::kGestureScrollUpdate,
WebInputEvent::kNoModifiers, base::TimeTicks::Now(),
WebGestureDevice::kTouchscreen);
event.SetPositionInWidget(gfx::PointF(x, y));
event.SetPositionInScreen(gfx::PointF(x, y));
event.data.scroll_update.delta_x = delta_x;
event.data.scroll_update.delta_y = delta_y;
if (is_in_inertial_phase) {
event.data.scroll_update.inertial_phase =
WebGestureEvent::InertialPhaseState::kMomentum;
event.SetTimeStamp(Compositor().LastFrameTime());
}
event.SetFrameScale(1);
GetWebFrameWidget().DispatchThroughCcInputHandler(event);
}
void ScrollSnapTest::ScrollEnd(double x, double y, bool is_in_inertial_phase) {
WebGestureEvent event(WebInputEvent::Type::kGestureScrollEnd,
WebInputEvent::kNoModifiers, base::TimeTicks::Now(),
WebGestureDevice::kTouchscreen);
event.SetPositionInWidget(gfx::PointF(x, y));
event.SetPositionInScreen(gfx::PointF(x, y));
event.data.scroll_end.inertial_phase =
is_in_inertial_phase ? WebGestureEvent::InertialPhaseState::kMomentum
: WebGestureEvent::InertialPhaseState::kNonMomentum;
GetWebFrameWidget().DispatchThroughCcInputHandler(event);
}
void ScrollSnapTest::SetInitialScrollOffset(double x, double y) {
Element* scroller = GetDocument().getElementById(AtomicString("scroller"));
scroller->GetLayoutBoxForScrolling()
->GetScrollableArea()
->ScrollToAbsolutePositionForTest(gfx::PointF(x, y));
ASSERT_EQ(scroller->scrollLeft(), x);
ASSERT_EQ(scroller->scrollTop(), y);
}
TEST_F(ScrollSnapTest, ScrollSnapOnX) {
SetUpForDiv();
SetInitialScrollOffset(50, 150);
Compositor().BeginFrame();
GestureScroll(100, 100, -50, 0);
Element* scroller = GetDocument().getElementById(AtomicString("scroller"));
// Snaps to align the area at start.
ASSERT_EQ(scroller->scrollLeft(), 200);
// An x-locked scroll ignores snap points on y.
ASSERT_EQ(scroller->scrollTop(), 150);
}
TEST_F(ScrollSnapTest, ScrollSnapOnY) {
SetUpForDiv();
SetInitialScrollOffset(150, 50);
Compositor().BeginFrame();
GestureScroll(100, 100, 0, -50);
Element* scroller = GetDocument().getElementById(AtomicString("scroller"));
// A y-locked scroll ignores snap points on x.
ASSERT_EQ(scroller->scrollLeft(), 150);
// Snaps to align the area at start.
ASSERT_EQ(scroller->scrollTop(), 200);
}
TEST_F(ScrollSnapTest, ScrollSnapOnBoth) {
SetUpForDiv();
SetInitialScrollOffset(50, 50);
Compositor().BeginFrame();
GestureScroll(100, 100, -50, -50);
Element* scroller = GetDocument().getElementById(AtomicString("scroller"));
// A scroll gesture that has move in both x and y would snap on both axes.
ASSERT_EQ(scroller->scrollLeft(), 200);
ASSERT_EQ(scroller->scrollTop(), 200);
}
TEST_F(ScrollSnapTest, AnimateFlingToArriveAtSnapPoint) {
SetUpForDiv();
// Vertically align with the area.
SetInitialScrollOffset(0, 200);
Compositor().BeginFrame();
Element* scroller = GetDocument().getElementById(AtomicString("scroller"));
ASSERT_EQ(scroller->scrollLeft(), 0);
ASSERT_EQ(scroller->scrollTop(), 200);
ScrollBegin(100, 100, -5, 0);
// Starts with a non-inertial GSU.
ScrollUpdate(100, 100, -5, 0);
Compositor().BeginFrame();
// Simulate a decaying fling sequence with multiple inertial GSUs.
// On Android, the first fast GSU (delta -5) triggers a
// kConstrainedNativeFling because it is predicted by the
// kDistanceEstimatorScalar to reach the extremity.
// The second slower GSU (delta -3) simulates deceleration. The remaining
// estimated displacement is no longer "fast enough" to reach the extremity,
// triggering the transition to the standard snap fling animation.
ScrollUpdate(95, 100, -5, 0, true);
Compositor().BeginFrame(0.016);
ScrollUpdate(90, 100, -3, 0, true);
ScrollEnd(87, 100);
// Animate halfway through the fling.
Compositor().BeginFrame(0.25);
ASSERT_GT(scroller->scrollLeft(), 150);
ASSERT_LT(scroller->scrollLeft(), 180);
ASSERT_EQ(scroller->scrollTop(), 200);
// Finish the animation.
Compositor().BeginFrame(0.6);
ASSERT_EQ(scroller->scrollLeft(), 200);
ASSERT_EQ(scroller->scrollTop(), 200);
}
TEST_F(ScrollSnapTest, SnapWhenBodyViewportDefining) {
v8::HandleScope HandleScope(
WebView().GetPage()->GetAgentGroupScheduler().Isolate());
WebView().MainFrameViewWidget()->Resize(gfx::Size(300, 300));
SimRequest request("https://example.com/test.html", "text/html");
LoadURL("https://example.com/test.html");
request.Complete(R"HTML(
)HTML");
Compositor().BeginFrame();
// The scroller snaps to the snap area that is closest to the origin (0,0) on
// the initial layout.
ASSERT_EQ(Window().scrollX(), 0);
ASSERT_EQ(Window().scrollY(), 0);
// The scroll delta needs to be large enough such that the closer snap area
// will be the one at (200,200).
// i.e. distance((200,200), (110,110)) < distance((0,0), (110,110))
GestureScroll(100, 100, -110, -110, true);
// Sanity check that body is the viewport defining element
ASSERT_EQ(GetDocument().body(), GetDocument().ViewportDefiningElement());
// When body is viewport defining and overflows then any snap points on the
// body element will be captured by layout view as the snap container.
ASSERT_EQ(Window().scrollX(), 200);
ASSERT_EQ(Window().scrollY(), 200);
}
TEST_F(ScrollSnapTest, SnapWhenHtmlViewportDefining) {
v8::HandleScope HandleScope(
WebView().GetPage()->GetAgentGroupScheduler().Isolate());
WebView().MainFrameViewWidget()->Resize(gfx::Size(300, 300));
SimRequest request("https://example.com/test.html", "text/html");
LoadURL("https://example.com/test.html");
request.Complete(R"HTML(
)HTML");
Compositor().BeginFrame();
// The scroller snaps to the snap area that is closest to the origin (0,0) on
// the initial layout.
ASSERT_EQ(Window().scrollX(), 0);
ASSERT_EQ(Window().scrollY(), 0);
// The scroll delta needs to be large enough such that the closer snap area
// will be the one at (200,200).
// i.e. distance((200,200), (110,110)) < distance((0,0), (110,110))
GestureScroll(100, 100, -110, -110, true);
// Sanity check that document element is the viewport defining element
ASSERT_EQ(GetDocument().documentElement(),
GetDocument().ViewportDefiningElement());
// When document is viewport defining and overflows then any snap ponts on the
// document element will be captured by layout view as snap container.
ASSERT_EQ(Window().scrollX(), 200);
ASSERT_EQ(Window().scrollY(), 200);
}
TEST_F(ScrollSnapTest, SnapWhenBodyOverflowHtmlViewportDefining) {
v8::HandleScope HandleScope(
WebView().GetPage()->GetAgentGroupScheduler().Isolate());
WebView().MainFrameViewWidget()->Resize(gfx::Size(300, 300));
SimRequest request("https://example.com/test.html", "text/html");
LoadURL("https://example.com/test.html");
request.Complete(R"HTML(
)HTML");
Compositor().BeginFrame();
// The scroller snaps to the snap area that is closest to the origin (0,0) on
// the initial layout.
Element* body = GetDocument().body();
ASSERT_EQ(body->scrollLeft(), 0);
ASSERT_EQ(body->scrollTop(), 0);
// The scroll delta needs to be large enough such that the closer snap area
// will be the one at (200,200).
// i.e. distance((200,200), (110,110)) < distance((0,0), (110,110))
GestureScroll(100, 100, -110, -110);
// Sanity check that document element is the viewport defining element
ASSERT_EQ(GetDocument().documentElement(),
GetDocument().ViewportDefiningElement());
// When body and document elements are both scrollable then body element
// should capture snap points defined on it as opposed to layout view.
ASSERT_EQ(body->scrollLeft(), 200);
ASSERT_EQ(body->scrollTop(), 200);
}
TEST_F(ScrollSnapTest, ResizeDuringGesture) {
ResizeView(gfx::Size(400, 400));
SimRequest request("https://example.com/test.html", "text/html");
LoadURL("https://example.com/test.html");
request.Complete(R"HTML(
)HTML");
Compositor().BeginFrame();
Element* viewport = GetDocument().scrollingElement();
ASSERT_EQ(viewport->scrollLeft(), 0);
ASSERT_EQ(viewport->scrollTop(), 0);
ScrollBegin(10, 10, -75, -75);
ScrollUpdate(10, 10, -75, -75);
Compositor().BeginFrame();
ASSERT_EQ(viewport->scrollLeft(), 75);
ASSERT_EQ(viewport->scrollTop(), 75);
ResizeView(gfx::Size(450, 450));
Compositor().BeginFrame();
// After mid-gesture resize, we should still be at 75.
ASSERT_EQ(viewport->scrollLeft(), 75);
ASSERT_EQ(viewport->scrollTop(), 75);
ScrollEnd(10, 10);
// The scrollend is deferred for the snap animation in cc::InputHandler; wait
// for the animation to finish. (We pss raster = true to ensure that we call
// LayerTreeHostImpl::UpdateAnimationState, which will set start time and
// transition to KeyframeModel::RUNNING.)
Compositor().BeginFrame(0.016, true);
Compositor().BeginFrame(0.3);
// Once the snap animation is finished, we run a deferred SnapAfterLayout.
ASSERT_EQ(viewport->scrollLeft(), 50);
ASSERT_EQ(viewport->scrollTop(), 50);
}
TEST_F(ScrollSnapTest, SnapAreaResizeDuringScrollAnimation) {
v8::HandleScope HandleScope(
WebView().GetPage()->GetAgentGroupScheduler().Isolate());
WebView().MainFrameViewWidget()->Resize(gfx::Size(800, 600));
SimRequest request("https://example.com/test.html", "text/html");
LoadURL("https://example.com/test.html");
request.Complete(
R"HTML(
)HTML");
Compositor().BeginFrame();
Element* box5 = GetDocument().getElementById(AtomicString("snapbox5"));
Element* scroller =
GetDocument().getElementById(AtomicString("snapscroller"));
Compositor().BeginFrame();
double last_offset = scroller->scrollLeft();
EXPECT_EQ(box5->clientHeight(), 50);
// Target the left edge of the last box. Make it an unaligned position using a
// small delta to verify snapping happens.
const double delta = 20;
const double target_offset = box5->OffsetLeft() + delta;
scroller->scrollToForTesting(target_offset, 0);
// Make some progress.
Compositor().BeginFrame(); // update run_state_.
Compositor().BeginFrame(); // Set start_time = now.
Compositor().BeginFrame(0.2);
EXPECT_GT(scroller->scrollLeft(), last_offset);
last_offset = scroller->scrollLeft();
// Make some more progress.
Compositor().BeginFrame(0.8);
EXPECT_GT(scroller->scrollLeft(), last_offset);
last_offset = scroller->scrollLeft();
// Sanity-check that the layout change happened.
EXPECT_EQ(box5->clientHeight(), 100);
// Finish the scroll.
Compositor().BeginFrame(1.0);
EXPECT_EQ(scroller->scrollLeft(), box5->OffsetLeft());
}
} // namespace blink