[css-flexbox] Simplify the "child intrinsic height" logic

third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 460 matching lines @@
     return flexLength;
 }
 
 LayoutUnit LayoutFlexibleBox::crossAxisExtentForChild(const LayoutBox& child) const
 {
     return isHorizontalFlow() ? child.size().height() : child.size().width();
 }
 
 static inline LayoutUnit constrainedChildIntrinsicContentLogicalHeight(const LayoutBox& child)
 {
+    // TODO(cbiesinger): scrollbar height?
     LayoutUnit childIntrinsicContentLogicalHeight = child.intrinsicContentLogicalHeight();
     return child.constrainLogicalHeightByMinMax(childIntrinsicContentLogicalHeight + child.borderAndPaddingLogicalHeight(), childIntrinsicContentLogicalHeight);
 }
 
-LayoutUnit LayoutFlexibleBox::childIntrinsicHeight(const LayoutBox& child) const
+LayoutUnit LayoutFlexibleBox::childIntrinsicLogicalHeight(const LayoutBox& child) const
 {
-    if (child.isHorizontalWritingMode() && needToStretchChildLogicalHeight(child))
+    // This should only be called if the logical height is the cross size
+    DCHECK(!hasOrthogonalFlow(child));
+    if (needToStretchChildLogicalHeight(child))
         return constrainedChildIntrinsicContentLogicalHeight(child);
-    // If our height is auto, make sure that our returned height is unaffected by earlier layouts by
-    // returning the max preferred height (=logical width)
-    if (!child.isHorizontalWritingMode() && child.styleRef().height().isAuto())
-        return child.maxPreferredLogicalWidth();
-    return child.size().height();
+    return child.logicalHeight();
 }
 
-LayoutUnit LayoutFlexibleBox::childIntrinsicWidth(const LayoutBox& child) const
+LayoutUnit LayoutFlexibleBox::childIntrinsicLogicalWidth(const LayoutBox& child) const
 {
-    if (!child.isHorizontalWritingMode() && needToStretchChildLogicalHeight(child))
-        return constrainedChildIntrinsicContentLogicalHeight(child);
-    if (child.isHorizontalWritingMode() && child.styleRef().width().isAuto()) {
-        // This value is already clamped by min/max-width
+    // This should only be called if the logical width is the cross size
+    DCHECK(hasOrthogonalFlow(child));
+    // If our height is auto, make sure that our returned height is unaffected by earlier layouts by
+    // returning the max preferred logical width
+    if (!crossAxisLengthIsDefinite(child, child.styleRef().logicalWidth()))
         return child.maxPreferredLogicalWidth();
-    }
-    return child.size().width();
+
+    return child.logicalWidth();
 }
 
 LayoutUnit LayoutFlexibleBox::crossAxisIntrinsicExtentForChild(const LayoutBox& child) const
 {
-    return isHorizontalFlow() ? childIntrinsicHeight(child) : childIntrinsicWidth(child);
+    return hasOrthogonalFlow(child) ? childIntrinsicLogicalWidth(child) : childIntrinsicLogicalHeight(child);
 }
 
 LayoutUnit LayoutFlexibleBox::mainAxisExtentForChild(const LayoutBox& child) const
 {
     return isHorizontalFlow() ? child.size().width() : child.size().height();
 }
 
 LayoutUnit LayoutFlexibleBox::mainAxisContentExtentForChild(const LayoutBox& child) const
 {
     return isHorizontalFlow() ? child.contentWidth() : child.contentHeight();
@@ skipping 1042 matching lines @@
     // So the child will automatically stretch if our cross axis is the child's inline axis. That's the case if:
     // - We are horizontal and the child is in vertical writing mode
     // - We are vertical and the child is in horizontal writing mode
     // Otherwise, we need to stretch if the cross axis size is auto.
     if (alignmentForChild(child) != ItemPositionStretch)
         return false;
 
     if (isHorizontalFlow() != child.styleRef().isHorizontalWritingMode())
         return false;
 
-    // TODO(cbiesinger): what about indefinite percentage heights?
-    return isHorizontalFlow() ? child.styleRef().height().isAuto() : child.styleRef().width().isAuto();
+    return child.styleRef().logicalHeight().isAuto();
 }
 
 bool LayoutFlexibleBox::childHasIntrinsicMainAxisSize(const LayoutBox& child) const
 {
     bool result = false;
     if (isHorizontalFlow() != child.styleRef().isHorizontalWritingMode()) {
         Length childFlexBasis = flexBasisForChild(child);
         Length childMinSize = isHorizontalFlow() ? child.style()->minWidth() : child.style()->minHeight();
         Length childMaxSize = isHorizontalFlow() ? child.style()->maxWidth() : child.style()->maxHeight();
         if (childFlexBasis.isIntrinsic() || childMinSize.isIntrinsicOrAuto() || childMaxSize.isIntrinsic())
@@ skipping 268 matching lines @@
             DCHECK(child);
             if (alignmentForChild(*child) == ItemPositionBaseline && !hasAutoMarginsInCrossAxis(*child) && minMarginAfterBaseline)
                 adjustAlignmentForChild(*child, minMarginAfterBaseline);
         }
     }
 }
 
 void LayoutFlexibleBox::applyStretchAlignmentToChild(LayoutBox& child, LayoutUnit lineCrossAxisExtent)
 {
     if (!hasOrthogonalFlow(child) && child.style()->logicalHeight().isAuto()) {
-        LayoutUnit heightBeforeStretching = needToStretchChildLogicalHeight(child) ? constrainedChildIntrinsicContentLogicalHeight(child) : child.logicalHeight();
+        LayoutUnit heightBeforeStretching = childIntrinsicLogicalHeight(child);
         LayoutUnit stretchedLogicalHeight = std::max(child.borderAndPaddingLogicalHeight(), heightBeforeStretching + availableAlignmentSpaceForChildBeforeStretching(lineCrossAxisExtent, child));
         DCHECK(!child.needsLayout());
         LayoutUnit desiredLogicalHeight = child.constrainLogicalHeightByMinMax(stretchedLogicalHeight, heightBeforeStretching - child.borderAndPaddingLogicalHeight());
 
         // FIXME: Can avoid laying out here in some cases. See https://webkit.org/b/87905.
         bool childNeedsRelayout = desiredLogicalHeight != child.logicalHeight();
         if (child.isLayoutBlock() && toLayoutBlock(child).hasPercentHeightDescendants() && m_relaidOutChildren.contains(&child)) {
             // Have to force another relayout even though the child is sized correctly, because
             // its descendants are not sized correctly yet. Our previous layout of the child was
             // done without an override height set. So, redo it here.
@@ skipping 49 matching lines @@
             DCHECK(child);
             LayoutUnit lineCrossAxisExtent = lineContexts[lineNumber].crossAxisExtent;
             LayoutUnit originalOffset = lineContexts[lineNumber].crossAxisOffset - crossAxisStartEdge;
             LayoutUnit newOffset = contentExtent - originalOffset - lineCrossAxisExtent;
             adjustAlignmentForChild(*child, newOffset - originalOffset);
         }
     }
 }
 
 } // namespace blink