Refine the fix for 9805 to really get all the complex cases right.

        Reviewed by Eric

        * rendering/RenderBlock.cpp:
        (WebCore::RenderBlock::clearFloatsIfNeeded):
        (WebCore::RenderBlock::handleBottomOfBlock):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@16444 268f45cc-cd09-0410-ab3c-d52691b4dbfc

diff --git a/WebCore/ChangeLog b/WebCore/ChangeLog
index 1aa80f5f4d364fc58cdd09ebf5ddbe244ca58f30..11998301a1546dd08174307eee016221d2370ada 100644 (file)
--- a/WebCore/ChangeLog
+++ b/WebCore/ChangeLog
@@ -1,3 +1,13 @@
+2006-09-19  David Hyatt  <hyatt@apple.com>
+
+        Refine the fix for 9805 to really get all the complex cases right.
+
+        Reviewed by Eric
+
+        * rendering/RenderBlock.cpp:
+        (WebCore::RenderBlock::clearFloatsIfNeeded):
+        (WebCore::RenderBlock::handleBottomOfBlock):
+
 2006-09-18  David Hyatt  <hyatt@apple.com>
 
         Fix for 9805, <hr> not positioned properly following a previous empty sibling

diff --git a/WebCore/rendering/RenderBlock.cpp b/WebCore/rendering/RenderBlock.cpp
index 53d6bbe297ef95a8f1a2c3b900883d713043796f..a6bef477399bfae9e7658db367345be053be5460 100644 (file)
--- a/WebCore/rendering/RenderBlock.cpp
+++ b/WebCore/rendering/RenderBlock.cpp
@@ -858,16 +858,23 @@ void RenderBlock::clearFloatsIfNeeded(RenderObject* child, MarginInfo& marginInf
         // The child needs to be lowered.  Move the child so that it just clears the float.
         child->setPos(child->xPos(), child->yPos() + heightIncrease);
 
-        // Increase our height by the amount we had to clear.
-        m_height += heightIncrease;
         if (child->isSelfCollapsingBlock()) {
             // For self-collapsing blocks that clear, they can still collapse their
             // margins with following siblings.  Reset the current margins to represent
             // the self-collapsing block's margins only.
             marginInfo.setPosMargin(max(child->maxTopMargin(true), child->maxBottomMargin(true)));
             marginInfo.setNegMargin(max(child->maxTopMargin(false), child->maxBottomMargin(false)));
+            
+            // Adjust our height such that we are ready to be collapsed with subsequent siblings.
+            m_height = child->yPos() - max(0, marginInfo.margin());
+            
+            // Set a flag that we cleared a float so that we know both to increase the height of the block
+            // to compensate for the clear and to avoid collapsing our margins with the parent block's
+            // bottom margin.
             marginInfo.setSelfCollapsingBlockClearedFloat(true);
-        }
+        } else
+            // Increase our height by the amount we had to clear.
+            m_height += heightIncrease;
         
         if (marginInfo.canCollapseWithTop()) {
             // We can no longer collapse with the top of the block since a clear
@@ -983,6 +990,13 @@ void RenderBlock::handleBottomOfBlock(int top, int bottom, MarginInfo& marginInf
     // collapse it with the bottom of the block.
     if (!marginInfo.selfCollapsingBlockClearedFloat())
         marginInfo.setAtBottomOfBlock(true);
+    else {
+        // We have to special case the negative margin situation (where the collapsed
+        // margin of the self-collapsing block is negative), since there's no need
+        // to make an adjustment in that case.
+        if (marginInfo.margin() < 0)
+            marginInfo.clearMargin();
+    }
 
     // If we can't collapse with children then go ahead and add in the bottom margin.
     if (!marginInfo.canCollapseWithBottom() && !marginInfo.canCollapseWithTop()