visualWordPosition should operate on a clean tree

alanbaradlay · alanbaradlay · commit 53f771a82d4f · 2021-09-01T14:43:42.000Z
https://bugs.webkit.org/show_bug.cgi?id=229744 <rdar://80684065> Reviewed by Antti Koivisto. This function expects the tree to not be mutated while walking the inline runs. * editing/VisibleUnits.cpp: (WebCore::visualWordPosition): Canonical link: https://commits.webkit.org/241179@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@281847 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
@@ -1,3 +1,16 @@
+2021-09-01  Alan Bujtas  <zalan@apple.com>
+
+        visualWordPosition should operate on a clean tree
+        https://bugs.webkit.org/show_bug.cgi?id=229744
+        <rdar://80684065>
+
+        Reviewed by Antti Koivisto.
+
+        This function expects the tree to not be mutated while walking the inline runs.
+
+        * editing/VisibleUnits.cpp:
+        (WebCore::visualWordPosition):
+
 2021-09-01  Myles C. Maxfield  <mmaxfield@apple.com>
 
         document.fonts.size needs to update style so it doesn't return stale values
diff --git a/Source/WebCore/editing/VisibleUnits.cpp b/Source/WebCore/editing/VisibleUnits.cpp
@@ -309,9 +309,11 @@ enum CursorMovementDirection { MoveLeft, MoveRight };
 static VisiblePosition visualWordPosition(const VisiblePosition& visiblePosition, CursorMovementDirection direction, 
     bool skipsSpaceWhenMovingRight)
 {
-    if (visiblePosition.isNull())
+    if (visiblePosition.isNull() || !visiblePosition.deepEquivalent().document())
         return VisiblePosition();
 
+    visiblePosition.deepEquivalent().document()->updateLayoutIgnorePendingStylesheets();
+
     TextDirection blockDirection = directionOfEnclosingBlock(visiblePosition.deepEquivalent());
     LayoutIntegration::RunIterator previouslyVisitedRun;
     VisiblePosition current = visiblePosition;
