Changeset 252205 in webkit

Timestamp:

Nov 7, 2019 2:18:37 PM (5 years ago)

Author:

rniwa@webkit.org

Message:

Integrate scroll event into HTML5 event loop
​https://bugs.webkit.org/show_bug.cgi?id=203839
<rdar://problem/56890922>

Reviewed by Simon Fraser.

Source/WebCore:

Dispatch scroll events on each pending scroll event targets inside the update-the-rendering step
of the event loop as specified in the HTML5 and CSSOM View Module specifications:
​https://html.spec.whatwg.org/multipage/webappapis.html#update-the-rendering
​https://drafts.csswg.org/cssom-view/#run-the-scroll-steps

The new behavior also matches that of Chrome and Firefox.

Like resize event, the current visual viewport specification does not specify when scroll event
is dispatched on visualViewport interface: ​https://github.com/WICG/visual-viewport/issues/66
For now, we always dispatch upon it after dispatching on all pending scroll event targets.

Tests: fast/events/scroll-multiple-elements-in-rendering-update.html

fast/events/scroll-subframe-in-rendering-update.html
fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe.html

• dom/Document.cpp:

(WebCore::Document::addPendingScrollEventTarget): Added.
(WebCore::Document::setNeedsVisualViewportScrollEvent): Added.
(WebCore::Document::runScrollSteps): Added. This implements run the scroll steps in CSS OM View.

• dom/Document.h:
• dom/DocumentEventQueue.cpp:

(WebCore::DocumentEventQueue::enqueueOrDispatchScrollEvent): Deleted.
(WebCore::DocumentEventQueue::enqueueScrollEvent): Deleted.

• dom/DocumentEventQueue.h:
• page/EventHandler.cpp:

(WebCore::EventHandler::sendScrollEvent):

• page/Page.cpp:

(WebCore::Page::updateRendering): Invoke runScrollSteps on each document in the frame tree order.

• page/VisualViewport.cpp:

(WebCore::VisualViewport::update):
(WebCore::VisualViewport::enqueueScrollEvent): Deleted.

• page/VisualViewport.h:
• rendering/RenderLayer.cpp:

(WebCore::RenderLayer::scrollTo):

• rendering/RenderListBox.cpp:

(WebCore::RenderListBox::scrollTo):

LayoutTests:

Added tests to test the timing at which scroll events are fired across multiple elements and documents,
and with visualViewport, and updated the existing tests to work with the new timing.

• editing/selection/overflow-scroll-while-selecting-text.html:
• fast/events/scroll-multiple-elements-in-rendering-update-expected.txt: Added.
• fast/events/scroll-multiple-elements-in-rendering-update.html: Added.
• fast/events/scroll-subframe-in-rendering-update-expected.txt: Added.
• fast/events/scroll-subframe-in-rendering-update.html: Added.
• fast/scrolling/programmatic-scroll-to-negative-offset.html:
• fast/shadow-dom/trusted-event-scoped-flags.html:
• fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe-expected.txt: Added.
• fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe.html: Added.
• tiled-drawing/scrolling/fast-scroll-div-latched-mainframe.html:

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/editing/selection/overflow-scroll-while-selecting-text.html (modified) (1 diff)
• LayoutTests/fast/events/scroll-subframe-in-rendering-update-expected.txt (added)
• LayoutTests/fast/events/scroll-subframe-in-rendering-update.html (added)
• LayoutTests/fast/scrolling/programmatic-scroll-to-negative-offset.html (modified) (1 diff)
• LayoutTests/fast/shadow-dom/trusted-event-scoped-flags.html (modified) (1 diff)
• LayoutTests/fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe-expected.txt (added)
• LayoutTests/fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe.html (added)
• LayoutTests/tiled-drawing/scrolling/fast-scroll-div-latched-mainframe.html (modified) (2 diffs)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/dom/Document.cpp (modified) (1 diff)
• Source/WebCore/dom/Document.h (modified) (3 diffs)
• Source/WebCore/dom/DocumentEventQueue.cpp (modified) (1 diff)
• Source/WebCore/dom/DocumentEventQueue.h (modified) (1 diff)
• Source/WebCore/page/EventHandler.cpp (modified) (1 diff)
• Source/WebCore/page/Page.cpp (modified) (2 diffs)
• Source/WebCore/page/VisualViewport.cpp (modified) (2 diffs)
• Source/WebCore/page/VisualViewport.h (modified) (1 diff)
• Source/WebCore/rendering/RenderLayer.cpp (modified) (1 diff)
• Source/WebCore/rendering/RenderListBox.cpp (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2019-11-06  Ryosuke Niwa  <rniwa@webkit.org>
+
+        Integrate scroll event into HTML5 event loop
+        https://bugs.webkit.org/show_bug.cgi?id=203839
+        <rdar://problem/56890922>
+
+        Reviewed by Simon Fraser.
+
+        Added tests to test the timing at which scroll events are fired across multiple elements and documents,
+        and with visualViewport, and updated the existing tests to work with the new timing.
+
+        * editing/selection/overflow-scroll-while-selecting-text.html:
+        * fast/events/scroll-multiple-elements-in-rendering-update-expected.txt: Added.
+        * fast/events/scroll-multiple-elements-in-rendering-update.html: Added.
+        * fast/events/scroll-subframe-in-rendering-update-expected.txt: Added.
+        * fast/events/scroll-subframe-in-rendering-update.html: Added.
+        * fast/scrolling/programmatic-scroll-to-negative-offset.html:
+        * fast/shadow-dom/trusted-event-scoped-flags.html:
+        * fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe-expected.txt: Added.
+        * fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe.html: Added.
+        * tiled-drawing/scrolling/fast-scroll-div-latched-mainframe.html:
+
 2019-11-07  Justin Fan  <justin_fan@apple.com>
 

trunk/LayoutTests/editing/selection/overflow-scroll-while-selecting-text.html

@@ -31 +31 @@
 const text = document.getElementById("text");
 text.scrollTo(0, 1000);
-addEventListener("load", () => text.scrollTo(0, 500));
-text.addEventListener("scroll", () => {
-    text.textContent = "";
-    testPassed("Successfully removed the text.");
-    finishJSTest();
+addEventListener("load", () => {
+    text.addEventListener("scroll", () => {
+        text.textContent = "";
+        testPassed("Successfully removed the text.");
+        finishJSTest();
+    });
+    text.scrollTo(0, 500);
 });
 </script>

trunk/LayoutTests/fast/scrolling/programmatic-scroll-to-negative-offset.html

@@ -26 +26 @@
                         scroller.scrollLeft = 50;
 
-                        scroller.addEventListener('scroll', (event) => {
-                                shouldBe("scroller.scrollLeft", "0");
-                                shouldBe("scroller.scrollLeft", "0");
-                                finishJSTest();
-                        }, false);
+                        setTimeout(() => {
+                        scroller.addEventListener('scroll', (event) => {
+                                shouldBe("scroller.scrollLeft", "0");
+                                shouldBe("scroller.scrollLeft", "0");
+                                finishJSTest();
+                        }, false);
 
-                        setTimeout(() => {
                                 scroller.scrollLeft = -200;
                                 scroller.scrollTop = -100;

trunk/LayoutTests/fast/shadow-dom/trusted-event-scoped-flags.html

@@ -97 +97 @@
     setTimeout(function () {
         window.scrollTo(0, 1000);
-        setTimeout(function () {
-            checkFlags('', {eventType: 'scroll', composed: false});
-            window.scrollTo(0, 0);
-            testResizeEvent();
-        }, 0);
+        requestAnimationFrame(() => {
+            setTimeout(function () {
+                checkFlags('', {eventType: 'scroll', composed: false});
+                window.scrollTo(0, 0);
+                testResizeEvent();
+            }, 0);
+        });
     }, 0);
 }

trunk/LayoutTests/tiled-drawing/scrolling/fast-scroll-div-latched-mainframe.html

@@ -48 +48 @@
 }
 
+let didCheck = false;
 function checkForScroll()
 {
+    if (didCheck)
+        return;
+    didCheck = true;
+
     // The div should not have scrolled at all.
     var pageScrollPositionAfter = document.scrollingElement.scrollTop;
@@ -97 +102 @@
 
         eventSender.monitorWheelEvents();
-        setTimeout(scrollTest, 0);
+        requestIdleCallback(() => {
+            setTimeout(scrollTest, 0);
+        });
     } else {
         var messageLocation = document.getElementById('parent');

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2019-11-06  Ryosuke Niwa  <rniwa@webkit.org>
+
+        Integrate scroll event into HTML5 event loop
+        https://bugs.webkit.org/show_bug.cgi?id=203839
+        <rdar://problem/56890922>
+
+        Reviewed by Simon Fraser.
+
+        Dispatch scroll events on each pending scroll event targets inside the update-the-rendering step
+        of the event loop as specified in the HTML5 and CSSOM View Module specifications:
+        https://html.spec.whatwg.org/multipage/webappapis.html#update-the-rendering
+        https://drafts.csswg.org/cssom-view/#run-the-scroll-steps
+
+        The new behavior also matches that of Chrome and Firefox.
+
+        Like resize event, the current visual viewport specification does not specify when scroll event
+        is dispatched on visualViewport interface: https://github.com/WICG/visual-viewport/issues/66
+        For now, we always dispatch upon it after dispatching on all pending scroll event targets.
+
+        Tests: fast/events/scroll-multiple-elements-in-rendering-update.html
+               fast/events/scroll-subframe-in-rendering-update.html
+               fast/visual-viewport/visual-viewport-scroll-after-resize-in-subframe.html
+
+        * dom/Document.cpp:
+        (WebCore::Document::addPendingScrollEventTarget): Added.
+        (WebCore::Document::setNeedsVisualViewportScrollEvent): Added.
+        (WebCore::Document::runScrollSteps): Added. This implements run the scroll steps in CSS OM View.
+        * dom/Document.h:
+        * dom/DocumentEventQueue.cpp:
+        (WebCore::DocumentEventQueue::enqueueOrDispatchScrollEvent): Deleted.
+        (WebCore::DocumentEventQueue::enqueueScrollEvent): Deleted.
+        * dom/DocumentEventQueue.h:
+        * page/EventHandler.cpp:
+        (WebCore::EventHandler::sendScrollEvent):
+        * page/Page.cpp:
+        (WebCore::Page::updateRendering): Invoke runScrollSteps on each document in the frame tree order.
+        * page/VisualViewport.cpp:
+        (WebCore::VisualViewport::update):
+        (WebCore::VisualViewport::enqueueScrollEvent): Deleted.
+        * page/VisualViewport.h:
+        * rendering/RenderLayer.cpp:
+        (WebCore::RenderLayer::scrollTo):
+        * rendering/RenderListBox.cpp:
+        (WebCore::RenderListBox::scrollTo):
+
 2019-11-07  Zalan Bujtas  <zalan@apple.com>
 

trunk/Source/WebCore/dom/Document.cpp

@@ -4002 +4002 @@
 }
 
+void Document::addPendingScrollEventTarget(ContainerNode& target)
+{
+    if (m_pendingScrollEventTargets.contains(&target))
+        return;
+
+    if (m_pendingScrollEventTargets.isEmpty())
+        scheduleTimedRenderingUpdate();
+
+    m_pendingScrollEventTargets.append(makeWeakPtr(target));
+}
+
+void Document::setNeedsVisualViewportScrollEvent()
+{
+    if (!m_needsVisualViewportScrollEvent)
+        scheduleTimedRenderingUpdate();
+    m_needsVisualViewportScrollEvent = true;
+}
+
+// https://drafts.csswg.org/cssom-view/#run-the-scroll-steps
+void Document::runScrollSteps()
+{
+    // FIXME: The order of dispatching is not specified: https://github.com/WICG/visual-viewport/issues/66.
+    if (!m_pendingScrollEventTargets.isEmpty()) {
+        LOG_WITH_STREAM(Events, stream << "Document" << this << "sending scroll events to pending scroll event targets");
+        auto currentTargets = WTFMove(m_pendingScrollEventTargets);
+        for (auto target : currentTargets) {
+            auto protectedTarget = makeRefPtr(target.get());
+            ASSERT(protectedTarget);
+            if (!protectedTarget)
+                continue;
+            auto bubbles = protectedTarget->isDocumentNode() ? Event::CanBubble::Yes : Event::CanBubble::No;
+            protectedTarget->dispatchEvent(Event::create(eventNames().scrollEvent, bubbles, Event::IsCancelable::No));
+        }
+    }
+    if (m_needsVisualViewportScrollEvent) {
+        LOG_WITH_STREAM(Events, stream << "Document" << this << "sending scroll events to visualViewport");
+        m_needsVisualViewportResizeEvent = false;
+        if (auto* window = domWindow())
+            window->visualViewport().dispatchEvent(Event::create(eventNames().scrollEvent, Event::CanBubble::No, Event::IsCancelable::No));
+    }
+}
+
 void Document::addAudioProducer(MediaProducer& audioProducer)
 {

trunk/Source/WebCore/dom/Document.h

@@ -1365 +1365 @@
     void runResizeSteps();
 
+    void addPendingScrollEventTarget(ContainerNode&);
+    void setNeedsVisualViewportScrollEvent();
+    void runScrollSteps();
+
     WEBCORE_EXPORT void addAudioProducer(MediaProducer&);
     WEBCORE_EXPORT void removeAudioProducer(MediaProducer&);
@@ -2020 +2024 @@
     bool m_needsDOMWindowResizeEvent { false };
     bool m_needsVisualViewportResizeEvent { false };
+    bool m_needsVisualViewportScrollEvent { false };
     bool m_isTimerThrottlingEnabled { false };
     bool m_isSuspended { false };
@@ -2035 +2040 @@
     bool m_isTelephoneNumberParsingAllowed { true };
 #endif
+
+    Vector<WeakPtr<ContainerNode>> m_pendingScrollEventTargets;
 
 #if ENABLE(MEDIA_STREAM)

trunk/Source/WebCore/dom/DocumentEventQueue.cpp

@@ -82 +82 @@
 }
 
-void DocumentEventQueue::enqueueOrDispatchScrollEvent(Node& target)
-{
-    ASSERT(&target.document() == &m_document);
-
-    // Per the W3C CSSOM View Module, scroll events fired at the document should bubble, others should not.
-    enqueueScrollEvent(target, target.isDocumentNode() ? Event::CanBubble::Yes : Event::CanBubble::No, Event::IsCancelable::No);
-}
-
-void DocumentEventQueue::enqueueScrollEvent(EventTarget& target, Event::CanBubble canBubble, Event::IsCancelable cancelable)
-{
-    if (m_isClosed)
-        return;
-
-    if (!m_document.hasListenerType(Document::SCROLL_LISTENER))
-        return;
-
-    if (!m_targetsWithQueuedScrollEvents.add(&target).isNewEntry)
-        return;
-
-    Ref<Event> scrollEvent = Event::create(eventNames().scrollEvent, canBubble, cancelable);
-    scrollEvent->setTarget(&target);
-    enqueueEvent(WTFMove(scrollEvent));
-}
-
 bool DocumentEventQueue::cancelEvent(Event& event)
 {

trunk/Source/WebCore/dom/DocumentEventQueue.h

@@ -48 +48 @@
     void close() override;
 
-    void enqueueOrDispatchScrollEvent(Node&);
-    void enqueueScrollEvent(EventTarget&, Event::CanBubble, Event::IsCancelable);
 
 private:

trunk/Source/WebCore/page/EventHandler.cpp

@@ -4030 +4030 @@
     Ref<Frame> protectedFrame(m_frame);
     setFrameWasScrolledByUser();
-    if (m_frame.view() && m_frame.document())
-        m_frame.document()->eventQueue().enqueueOrDispatchScrollEvent(*m_frame.document());
+    if (!m_frame.view())
+        return;
+    auto document = makeRefPtr(m_frame.document());
+    if (!document)
+        return;
+    document->addPendingScrollEventTarget(*document);
 }
 

trunk/Source/WebCore/page/Page.cpp

@@ -1291 +1291 @@
     layoutIfNeeded();
 
+    // Flush autofocus candidates
+
     forEachDocument([&](Document& document) {
         document.runResizeSteps();
     });
 
-    // FIXME: Run the scroll steps
+    forEachDocument([&](Document& document) {
+        document.runScrollSteps();
+    });
 
     forEachDocument([&](Document& document) {
@@ -1319 +1323 @@
         document->updateResizeObservations(*this);
 #endif
-
-    // FIXME: Flush autofocus candidates
-    // https://github.com/whatwg/html/issues/4992
 
     layoutIfNeeded();

trunk/Source/WebCore/page/VisualViewport.cpp

@@ -169 +169 @@
     }
 
+    RefPtr<Document> document = frame ? frame->document() : nullptr;
     if (m_offsetLeft != offsetLeft || m_offsetTop != offsetTop) {
-        enqueueScrollEvent();
+        if (document)
+            document->setNeedsVisualViewportScrollEvent();
         m_offsetLeft = offsetLeft;
         m_offsetTop = offsetTop;
     }
     if (m_width != width || m_height != height || m_scale != scale) {
-        if (auto* frame = this->frame())
-            frame->document()->setNeedsVisualViewportResize();
+        if (document)
+            document->setNeedsVisualViewportResize();
         m_width = width;
         m_height = height;
@@ -183 +185 @@
 }
 
-void VisualViewport::enqueueScrollEvent()
-{
-    auto* frame = this->frame();
-    if (!frame)
-        return;
-
-    frame->document()->eventQueue().enqueueScrollEvent(*this, Event::CanBubble::No, Event::IsCancelable::No);
-}
-
 } // namespace WebCore

trunk/Source/WebCore/page/VisualViewport.h

@@ -61 +61 @@
     void derefEventTarget() final { deref(); }
 
-    void enqueueResizeEvent();
-    void enqueueScrollEvent();
-
     void updateFrameLayout() const;
 

trunk/Source/WebCore/rendering/RenderLayer.cpp

@@ -2674 +2674 @@
     // Schedule the scroll and scroll-related DOM events.
     if (Element* element = renderer().element())
-        element->document().eventQueue().enqueueOrDispatchScrollEvent(*element);
+        element->document().addPendingScrollEventTarget(*element);
 
     if (scrollsOverflow())

trunk/Source/WebCore/rendering/RenderListBox.cpp

@@ -714 +714 @@
 
     repaint();
-    document().eventQueue().enqueueOrDispatchScrollEvent(selectElement());
+    document().addPendingScrollEventTarget(selectElement());
 }