Changeset 27486 in webkit

Timestamp:

Nov 6, 2007, 1:03:35 PM (17 years ago)

Author:

mitz@apple.com

Message:

WebCore:

Reviewed by Antti Koivisto and Dave Hyatt.

• fix <rdar://problem/5582961> Incorrect layout and floating object list corruption when CSS decreases a block's height

Test: fast/block/float/overhanging-after-height-decrease.html

• rendering/RenderBlock.cpp: (WebCore::RenderBlock::layoutBlock): If after calculating the height it turns out that there are overhanging floats that were not overhanging before, rescan children with overhanging floats and add them. (WebCore::RenderBlock::layoutBlockChildren): Added a parameter that returns the lowest float bottom of any of the children. (WebCore::RenderBlock::addOverhangingFloats): Changed to return the lowest float bottom.
• rendering/RenderBlock.h:

LayoutTests:

Reviewed by Antti Koivisto and Dave Hyatt.

• test for <rdar://problem/5582961> Incorrect layout and floating object list corruption when CSS decreases a block's height

• fast/block/float/overhanging-after-height-decrease.html: Added.
• platform/mac-leopard/fast/block: Added.
• platform/mac-leopard/fast/block/float: Added.
• platform/mac-leopard/fast/block/float/overhanging-after-height-decrease-expected.checksum: Added.
• platform/mac-leopard/fast/block/float/overhanging-after-height-decrease-expected.png: Added.
• platform/mac/fast/block/float/overhanging-after-height-decrease-expected.txt: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/block/float/overhanging-after-height-decrease.html (added)
• LayoutTests/platform/mac-leopard/fast/block (added)
• LayoutTests/platform/mac-leopard/fast/block/float (added)
• LayoutTests/platform/mac-leopard/fast/block/float/overhanging-after-height-decrease-expected.checksum (added)
• LayoutTests/platform/mac-leopard/fast/block/float/overhanging-after-height-decrease-expected.png (added)
• LayoutTests/platform/mac/fast/block/float/overhanging-after-height-decrease-expected.txt (added)
• WebCore/ChangeLog (modified) (1 diff)
• WebCore/rendering/RenderBlock.cpp (modified) (8 diffs)
• WebCore/rendering/RenderBlock.h (modified) (2 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2007-11-06  Dan Bernstein  <mitz@apple.com>
+
+        Reviewed by Antti Koivisto and Dave Hyatt.
+
+        - test for <rdar://problem/5582961> Incorrect layout and floating object list corruption when CSS decreases a block's height
+
+        * fast/block/float/overhanging-after-height-decrease.html: Added.
+        * platform/mac-leopard/fast/block: Added.
+        * platform/mac-leopard/fast/block/float: Added.
+        * platform/mac-leopard/fast/block/float/overhanging-after-height-decrease-expected.checksum: Added.
+        * platform/mac-leopard/fast/block/float/overhanging-after-height-decrease-expected.png: Added.
+        * platform/mac/fast/block/float/overhanging-after-height-decrease-expected.txt: Added.
+
 2007-11-05  Adele Peterson  <adele@apple.com>
 

trunk/WebCore/ChangeLog

@@ +1 @@
+2007-11-06  Dan Bernstein  <mitz@apple.com>
+
+        Reviewed by Antti Koivisto and Dave Hyatt.
+
+        - fix <rdar://problem/5582961> Incorrect layout and floating object list corruption when CSS decreases a block's height
+
+        Test: fast/block/float/overhanging-after-height-decrease.html
+
+        * rendering/RenderBlock.cpp:
+        (WebCore::RenderBlock::layoutBlock): If after calculating the height
+        it turns out that there are overhanging floats that were not overhanging
+        before, rescan children with overhanging floats and add them. 
+        (WebCore::RenderBlock::layoutBlockChildren): Added a parameter that
+        returns the lowest float bottom of any of the children.
+        (WebCore::RenderBlock::addOverhangingFloats): Changed to return the
+        lowest float bottom.
+        * rendering/RenderBlock.h:
+
 2007-11-06  Adele Peterson  <adele@apple.com>
 

trunk/WebCore/rendering/RenderBlock.cpp

@@ -578 +578 @@
     int repaintTop = 0;
     int repaintBottom = 0;
+    int maxFloatBottom = 0;
     if (childrenInline())
         layoutInlineChildren(relayoutChildren, repaintTop, repaintBottom);
     else
-        layoutBlockChildren(relayoutChildren);
+        layoutBlockChildren(relayoutChildren, maxFloatBottom);
 
     // Expand our intrinsic height to encompass floats.
@@ -597 +598 @@
     calcHeight();
     if (oldHeight != m_height) {
+        if (oldHeight > m_height && maxFloatBottom > m_height && !childrenInline()) {
+            // One of our children's floats may have become an overhanging float for us. We need to look for it.
+            for (RenderObject* child = firstChild(); child; child = child->nextSibling()) {
+                if (child->isBlockFlow() && !child->isFloatingOrPositioned()) {
+                    RenderBlock* block = static_cast<RenderBlock*>(child);
+                    if (block->floatBottom() + block->yPos() > m_height)
+                        addOverhangingFloats(block, block->xPos(), block->yPos());
+                }
+            }
+        }
         // We have to rebalance columns to the new height.
         layoutColumns(singleColumnBottom);
@@ -1133 +1144 @@
 }
 
-void RenderBlock::layoutBlockChildren(bool relayoutChildren)
+void RenderBlock::layoutBlockChildren(bool relayoutChildren, int& maxFloatBottom)
 {
     int top = borderTop() + paddingTop();
@@ -1149 +1160 @@
 
     int previousFloatBottom = 0;
+    maxFloatBottom = 0;
 
     RenderObject* child = firstChild();
@@ -1236 +1248 @@
         // If the child has overhanging floats that intrude into following siblings (or possibly out
         // of this block), then the parent gets notified of the floats now.
-        addOverhangingFloats(static_cast<RenderBlock *>(child), -child->xPos(), -child->yPos());
+        maxFloatBottom = max(maxFloatBottom, addOverhangingFloats(static_cast<RenderBlock *>(child), -child->xPos(), -child->yPos()));
 
         // Update our overflow in case the child spills out the block.
@@ -2632 +2644 @@
 }
 
-void RenderBlock::addOverhangingFloats(RenderBlock* child, int xoff, int yoff)
+int RenderBlock::addOverhangingFloats(RenderBlock* child, int xoff, int yoff)
 {
     // Prevent floats from being added to the canvas by the root element, e.g., <html>.
     if (child->hasOverflowClip() || !child->containsFloats() || child->isRoot())
-        return;
+        return 0;
+
+    int lowestFloatBottom = 0;
 
     // Floats that will remain the child's responsiblity to paint should factor into its
@@ -2643 +2657 @@
     DeprecatedPtrListIterator<FloatingObject> it(*child->m_floatingObjects);
     for (FloatingObject* r; (r = it.current()); ++it) {
-        if (child->yPos() + r->endY > height()) {
+        int bottom = child->yPos() + r->endY;
+        lowestFloatBottom = max(lowestFloatBottom, bottom);
+
+        if (bottom > height()) {
             // If the object is not in the list, we add it now.
             if (!containsFloat(r->node)) {
@@ -2677 +2694 @@
     }
     child->addVisualOverflow(floatsOverflowRect);
+    return lowestFloatBottom;
 }
 

trunk/WebCore/rendering/RenderBlock.h

@@ -111 +111 @@
     virtual void layout();
     virtual void layoutBlock(bool relayoutChildren);
-    void layoutBlockChildren(bool relayoutChildren);
+    void layoutBlockChildren(bool relayoutChildren, int& maxFloatBottom);
     void layoutInlineChildren(bool relayoutChildren, int& repaintTop, int& repaintBottom);
 
@@ -177 +177 @@
     virtual bool hasOverhangingFloats() { return !hasColumns() && floatBottom() > m_height; }
     void addIntrudingFloats(RenderBlock* prev, int xoffset, int yoffset);
-    void addOverhangingFloats(RenderBlock* child, int xoffset, int yoffset);
+    int addOverhangingFloats(RenderBlock* child, int xoffset, int yoffset);
 
     int nearestFloatBottom(int height) const;