RTL scrollbar has incorrect spacing for content added with delay

nmoucht · nmoucht · commit 38b37039fe85 · 2025-03-14T11:11:32.000-07:00
https://bugs.webkit.org/show_bug.cgi?id=284713 rdar://141556436 Reviewed by Simon Fraser. This patch works around a couple of AppKit issues, where setting the user direction when there isn't a host layer causes that setting to be lost, and setting the user direction doesn't immediately update. * Source/WebCore/page/scrolling/mac/ScrollerMac.h: * Source/WebCore/page/scrolling/mac/ScrollerMac.mm: (WebCore::ScrollerMac::updateValues): (WebCore::ScrollerMac::setScrollbarLayoutDirection): Canonical link: https://commits.webkit.org/292177@main
diff --git a/LayoutTests/fast/scrolling/mac/scrollbars/rtl-scrollbar-state-delayed-expected.txt b/LayoutTests/fast/scrolling/mac/scrollbars/rtl-scrollbar-state-delayed-expected.txt
@@ -0,0 +1,10 @@
+Test that rtl bit is set on scrollbar for rtl scrollable area when set with delay
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+PASS Scrollbar state: enabled,RTL
+PASS successfullyParsed is true
+
+TEST COMPLETE
+
diff --git a/LayoutTests/fast/scrolling/mac/scrollbars/rtl-scrollbar-state-delayed.html b/LayoutTests/fast/scrolling/mac/scrollbars/rtl-scrollbar-state-delayed.html
@@ -0,0 +1,56 @@
+<!DOCTYPE html> <!-- webkit-test-runner [ MockScrollbarsEnabled=false AsyncOverflowScrollingEnabled=true ] -->
+<html dir="rtl">
+<head>
+    <style>
+        .scroller {
+            margin: 10px;
+            width: 200px;
+            height: 200px;
+            border: 1px solid black;
+            overflow: auto;
+        }
+        .contents {
+            width: 100%;
+            height: 200%;
+        }
+    </style>
+    <script src="../../../../resources/js-test.js"></script>
+    <script src="../../../../resources/ui-helper.js"></script>
+    
+    <script>
+        jsTestIsAsync = true;
+        
+        if (window.internals)
+            internals.setUsesOverlayScrollbars(true);
+
+        async function doTest()
+        {
+            description('Test that rtl bit is set on scrollbar for rtl scrollable area when set with delay');
+            document.body.style.height = "1000px";
+
+            if (!window.internals) {
+                finishJSTest();
+                return;
+            }
+
+            await UIHelper.waitForConditionAsync(async () => {
+                let state = await UIHelper.verticalScrollbarState();
+                let isRTL = state.indexOf('RTL') != -1;
+                if (isRTL)
+                    testPassed('Scrollbar state: ' + state);
+                return isRTL;
+            });
+
+            finishJSTest();
+        }
+
+        window.addEventListener('load', () => {
+            setTimeout(() => {
+                doTest();
+            }, 500);
+        }, false);
+    </script>
+</head>
+<body>
+</body>
+</html>
diff --git a/Source/WebCore/page/scrolling/mac/ScrollerMac.h b/Source/WebCore/page/scrolling/mac/ScrollerMac.h
@@ -89,6 +89,7 @@ class ScrollerMac {
     ScrollerPairMac& m_pair;
     const ScrollbarOrientation m_orientation;
     IntPoint m_lastKnownMousePositionInScrollbar;
+    UserInterfaceLayoutDirection m_scrollbarLayoutDirection { UserInterfaceLayoutDirection::LTR };
 
     RetainPtr<CALayer> m_hostLayer;
     RetainPtr<NSScrollerImp> m_scrollerImp;
diff --git a/Source/WebCore/page/scrolling/mac/ScrollerMac.mm b/Source/WebCore/page/scrolling/mac/ScrollerMac.mm
@@ -370,6 +370,7 @@ - (void)invalidate
 
     BEGIN_BLOCK_OBJC_EXCEPTIONS
     [m_scrollerImp setEnabled:m_isEnabled];
+    [m_scrollerImp setUserInterfaceLayoutDirection: m_scrollbarLayoutDirection == UserInterfaceLayoutDirection::RTL ? NSUserInterfaceLayoutDirectionRightToLeft : NSUserInterfaceLayoutDirectionLeftToRight];
     [m_scrollerImp setBoundsSize:NSSizeFromCGSize([m_hostLayer bounds].size)];
     [m_scrollerImp setDoubleValue:values.value];
     [m_scrollerImp setPresentationValue:values.value];
@@ -465,6 +466,11 @@ - (void)invalidate
 
 void ScrollerMac::setScrollbarLayoutDirection(UserInterfaceLayoutDirection scrollbarLayoutDirection)
 {
+    if (m_scrollbarLayoutDirection == scrollbarLayoutDirection)
+        return;
+
+    m_scrollbarLayoutDirection = scrollbarLayoutDirection;
+    updateScrollbarStyle();
     [m_scrollerImp setUserInterfaceLayoutDirection: scrollbarLayoutDirection == UserInterfaceLayoutDirection::RTL ? NSUserInterfaceLayoutDirectionRightToLeft : NSUserInterfaceLayoutDirectionLeftToRight];
 }
 
