Changeset 259611 in webkit

Timestamp:

Apr 6, 2020, 4:34:51 PM (6 years ago)

Author:

Alan Bujtas

Message:

Delete line boxes when moving text renderers between block flows
​https://bugs.webkit.org/show_bug.cgi?id=210000

Reviewed by Antti Koivisto.

After style and/or tree mutation the existing line boxes are destroyed during the subsequent layout.
When the text renderer moves between block flows and the destination block flow initiates a different
type of line layout, we need to make sure the previous line content is cleaned up properly.

• rendering/RenderBlockFlow.cpp:

(WebCore::RenderBlockFlow::layoutSimpleLines):
(WebCore::RenderBlockFlow::layoutLFCLines):

• rendering/RenderText.cpp:

(WebCore::RenderText::removeAndDestroyTextBoxes):
(WebCore::RenderText::dirtyLineBoxes):
(WebCore::RenderText::deleteLineBoxes):

• rendering/RenderText.h:

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• rendering/RenderBlockFlow.cpp (modified) (2 diffs)
• rendering/RenderText.cpp (modified) (2 diffs)
• rendering/RenderText.h (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2020-04-06  Zalan Bujtas  <zalan@apple.com>
+
+        Delete line boxes when moving text renderers between block flows
+        https://bugs.webkit.org/show_bug.cgi?id=210000
+
+        Reviewed by Antti Koivisto.
+
+        After style and/or tree mutation the existing line boxes are destroyed during the subsequent layout.
+        When the text renderer moves between block flows and the destination block flow initiates a different
+        type of line layout, we need to make sure the previous line content is cleaned up properly.
+
+        * rendering/RenderBlockFlow.cpp:
+        (WebCore::RenderBlockFlow::layoutSimpleLines):
+        (WebCore::RenderBlockFlow::layoutLFCLines):
+        * rendering/RenderText.cpp:
+        (WebCore::RenderText::removeAndDestroyTextBoxes):
+        (WebCore::RenderText::dirtyLineBoxes):
+        (WebCore::RenderText::deleteLineBoxes):
+        * rendering/RenderText.h:
+
 2020-04-06  Ross Kirsling  <ross.kirsling@sony.com>
 

trunk/Source/WebCore/rendering/RenderBlockFlow.cpp

@@ -3716 +3716 @@
     }
 
-    for (auto& renderer : childrenOfType<RenderObject>(*this))
+    for (auto& renderer : childrenOfType<RenderObject>(*this)) {
+        if (is<RenderText>(renderer))
+            downcast<RenderText>(renderer).deleteLineBoxes();
         renderer.clearNeedsLayout();
+    }
 
     LayoutUnit lineLayoutHeight = SimpleLineLayout::computeFlowHeight(*this, simpleLineLayout);
@@ -3734 +3737 @@
     auto& layoutFormattingContextLineLayout = *this->layoutFormattingContextLineLayout();
 
-    for (auto& renderer : childrenOfType<RenderObject>(*this))
+    for (auto& renderer : childrenOfType<RenderObject>(*this)) {
+        if (is<RenderText>(renderer))
+            downcast<RenderText>(renderer).deleteLineBoxes();
         renderer.clearNeedsLayout();
+    }
 
     layoutFormattingContextLineLayout.layout();

trunk/Source/WebCore/rendering/RenderText.cpp

@@ -281 +281 @@
         m_lineBoxes.invalidateParentChildLists();
 #endif
-    m_lineBoxes.deleteAll();
+    deleteLineBoxes();
 }
 
@@ -1299 +1299 @@
 {
     if (fullLayout)
-        m_lineBoxes.deleteAll();
+        deleteLineBoxes();
     else if (!m_linesDirty)
         m_lineBoxes.dirtyAll();
     m_linesDirty = false;
+}
+
+void RenderText::deleteLineBoxes()
+{
+    m_lineBoxes.deleteAll();
 }
 

trunk/Source/WebCore/rendering/RenderText.h

@@ -72 +72 @@
     InlineTextBox* createInlineTextBox() { return m_lineBoxes.createAndAppendLineBox(*this); }
     void dirtyLineBoxes(bool fullLayout);
+    void deleteLineBoxes();
 
     void absoluteRects(Vector<IntRect>&, const LayoutPoint& accumulatedOffset) const final;