[CSS Grid Layout] Handling overflow on Content Alignment properties.

Source/core/rendering/RenderGrid.cpp

 /*
  * Copyright (C) 2011 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1084 matching lines @@
     LayoutUnit availableSpaceForRows = availableLogicalHeight(IncludeMarginBorderPadding);
     GridSizingData sizingData(gridColumnCount(), gridRowCount());
     computeUsedBreadthOfGridTracks(ForColumns, sizingData, availableSpaceForColumns);
     ASSERT(tracksAreWiderThanMinTrackBreadth(ForColumns, sizingData.columnTracks));
     computeUsedBreadthOfGridTracks(ForRows, sizingData, availableSpaceForRows);
     ASSERT(tracksAreWiderThanMinTrackBreadth(ForRows, sizingData.rowTracks));
 
     populateGridPositions(sizingData, availableSpaceForColumns, availableSpaceForRows);
     m_gridItemsOverflowingGridArea.resize(0);
 
-    LayoutUnit columnOffset = contentPositionAndDistributionColumnOffset(availableSpaceForColumns, style()->justifyContent(), style()->justifyContentDistribution(), m_columnPositions.size() - 1);
-    LayoutUnit rowOffset = contentPositionAndDistributionRowOffset(availableSpaceForRows, style()->alignContent(), style()->alignContentDistribution(), m_rowPositions.size() - 1);
+    LayoutUnit columnOffset = contentPositionAndDistributionColumnOffset(availableSpaceForColumns, style()->justifyContent(), style()->justifyContentDistribution(), style()->justifyContentOverflowAlignment(), m_columnPositions.size() - 1);
+    LayoutUnit rowOffset = contentPositionAndDistributionRowOffset(availableSpaceForRows, style()->alignContent(), style()->alignContentDistribution(), style()->alignContentOverflowAlignment(), m_rowPositions.size() - 1);
     LayoutSize contentPositionOffset(columnOffset, rowOffset);
 
     for (RenderBox* child = firstChildBox(); child; child = child->nextSiblingBox()) {
         if (child->isOutOfFlowPositioned()) {
             child->containingBlock()->insertPositionedObject(child);
             continue;
         }
 
         // Because the grid area cannot be styled, we don't need to adjust
         // the grid breadth to account for 'box-sizing'.
@@ skipping 505 matching lines @@
 static inline LayoutUnit offsetToStartEdge(bool isLeftToRight, LayoutUnit availableSpace)
 {
     return isLeftToRight ? LayoutUnit(0) : availableSpace;
 }
 
 static inline LayoutUnit offsetToEndEdge(bool isLeftToRight, LayoutUnit availableSpace)
 {
     return !isLeftToRight ? LayoutUnit(0) : availableSpace;
 }
 
-LayoutUnit RenderGrid::contentPositionAndDistributionColumnOffset(LayoutUnit availableFreeSpace, ContentPosition position, ContentDistributionType distribution, unsigned numberOfGridTracks) const
+LayoutUnit RenderGrid::contentPositionAndDistributionColumnOffset(LayoutUnit availableFreeSpace, ContentPosition position, ContentDistributionType distribution, OverflowAlignment overflow, unsigned numberOfGridTracks) const
 {
-    if (availableFreeSpace <= 0)
+    if (overflow == OverflowAlignmentSafe && availableFreeSpace <= 0)
         return 0;
 
     // FIXME: for the time being, spec states that it will always fallback for Grids, but
     // discussion is ongoing.
     if (distribution != ContentDistributionDefault && position == ContentPositionAuto)
         position = resolveContentDistributionFallback(distribution);
 
-    // FIXME: still pending of implementing support for the <overflow-position> keyword
-    // in justify-content and aling-content properties.
     switch (position) {
     case ContentPositionLeft:
         return 0;
     case ContentPositionRight:
         return availableFreeSpace;
     case ContentPositionCenter:
         return availableFreeSpace / 2;
     case ContentPositionFlexEnd:
         // Only used in flex layout, for other layout, it's equivalent to 'end'.
     case ContentPositionEnd:
         return offsetToEndEdge(style()->isLeftToRightDirection(), availableFreeSpace);
     case ContentPositionFlexStart:
         // Only used in flex layout, for other layout, it's equivalent to 'start'.
     case ContentPositionStart:
         return offsetToStartEdge(style()->isLeftToRightDirection(), availableFreeSpace);
     case ContentPositionBaseline:
     case ContentPositionLastBaseline:
         // FIXME: Implement the previous values. For now, we always 'start' align.
         // crbug.com/234191
         return offsetToStartEdge(style()->isLeftToRightDirection(), availableFreeSpace);
     case ContentPositionAuto:
         break;
     }
 
     ASSERT_NOT_REACHED();
     return 0;
 }
 
-LayoutUnit RenderGrid::contentPositionAndDistributionRowOffset(LayoutUnit availableFreeSpace, ContentPosition position, ContentDistributionType distribution, unsigned numberOfGridTracks) const
+LayoutUnit RenderGrid::contentPositionAndDistributionRowOffset(LayoutUnit availableFreeSpace, ContentPosition position, ContentDistributionType distribution, OverflowAlignment overflow, unsigned numberOfGridTracks) const
 {
-    if (availableFreeSpace <= 0)
+    if (overflow == OverflowAlignmentSafe && availableFreeSpace <= 0)
         return 0;
 
     // FIXME: for the time being, spec states that it will always fallback for Grids, but
     // discussion is ongoing.
     if (distribution != ContentDistributionDefault && position == ContentPositionAuto)
         position = resolveContentDistributionFallback(distribution);
 
-    // FIXME: still pending of implementing support for the <overflow-position> keyword
-    // in justify-content and align-content properties.
     switch (position) {
     case ContentPositionLeft:
         // The align-content's axis is always orthogonal to the inline-axis.
         return 0;
     case ContentPositionRight:
         // The align-content's axis is always orthogonal to the inline-axis.
         return 0;
     case ContentPositionCenter:
         return availableFreeSpace / 2;
     case ContentPositionFlexEnd:
@@ skipping 44 matching lines @@
     if (isOutOfFlowPositioned())
         return "RenderGrid (positioned)";
     if (isAnonymous())
         return "RenderGrid (generated)";
     if (isRelPositioned())
         return "RenderGrid (relative positioned)";
     return "RenderGrid";
 }
 
 } // namespace blink