Respect break-inside:avoid on table rows

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

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009, 2010, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 941 matching lines @@
     unsigned totalRows = m_grid.size();
 
     // Set the width of our section now.  The rows will also be this width.
     setLogicalWidth(table()->contentLogicalWidth());
     m_overflow.clear();
     m_overflowingCells.clear();
     m_forceSlowPaintPathWithOverflowingCell = false;
 
     int vspacing = table()->vBorderSpacing();
     unsigned nEffCols = table()->numEffectiveColumns();
+    bool isPaginated = view()->layoutState()->isPaginated();
 
     LayoutState state(*this, locationOffset());
 
     for (unsigned r = 0; r < totalRows; r++) {
         // Set the row's x/y position and width/height.
         LayoutTableRow* rowLayoutObject = m_grid[r].rowLayoutObject;
+        int paginationStrutOnRow = 0;
         if (rowLayoutObject) {
             rowLayoutObject->setLocation(LayoutPoint(0, m_rowPos[r]));
             rowLayoutObject->setLogicalWidth(logicalWidth());
             rowLayoutObject->setLogicalHeight(LayoutUnit(m_rowPos[r + 1] - m_rowPos[r] - vspacing));
             rowLayoutObject->updateLayerTransformAfterLayout();
             rowLayoutObject->clearAllOverflows();
             rowLayoutObject->addVisualEffectOverflow();
+            if (isPaginated) {
+                paginationStrutOnRow = paginationStrutForRow(rowLayoutObject, LayoutUnit(m_rowPos[r]));
+                for (unsigned rowIndex = r; paginationStrutOnRow && rowIndex <= totalRows; rowIndex++)

[mstensho (USE GERRIT), 2016/04/04 21:05:39]

Better check paginationStrutOnRow before entering the loop at all.

+                    m_rowPos[rowIndex] += paginationStrutOnRow;
+            }
         }
 
         int rowHeightIncreaseForPagination = 0;
 
         for (unsigned c = 0; c < nEffCols; c++) {
             CellStruct& cs = cellAt(r, c);
             LayoutTableCell* cell = cs.primaryCell();
 
             if (!cell || cs.inColSpan)
                 continue;
@@ skipping 59 matching lines @@
             LayoutRect oldCellRect = cell->frameRect();
 
             setLogicalPositionForCell(cell, c);
 
             if (!cell->needsLayout())
                 cell->markForPaginationRelayoutIfNeeded(layouter);
 
             cell->layoutIfNeeded();
 
             // FIXME: Make pagination work with vertical tables.
-            if (view()->layoutState()->pageLogicalHeight() && cell->logicalHeight() != rHeight) {
+            if (!paginationStrutOnRow && view()->layoutState()->pageLogicalHeight() && cell->logicalHeight() != rHeight) {
                 // FIXME: Pagination might have made us change size. For now just shrink or grow the cell to fit without doing a relayout.
                 // We'll also do a basic increase of the row height to accommodate the cell if it's bigger, but this isn't quite right
                 // either. It's at least stable though and won't result in an infinite # of relayouts that may never stabilize.
                 LayoutUnit oldLogicalHeight = cell->logicalHeight();
                 if (oldLogicalHeight > rHeight)
                     rowHeightIncreaseForPagination = std::max<int>(rowHeightIncreaseForPagination, oldLogicalHeight - rHeight);
                 cell->setLogicalHeight(LayoutUnit(rHeight));
                 cell->computeOverflow(oldLogicalHeight, false);
             }
 
@@ skipping 23 matching lines @@
         }
     }
 
     ASSERT(!needsLayout());
 
     setLogicalHeight(LayoutUnit(m_rowPos[totalRows]));
 
     computeOverflowFromCells(totalRows, nEffCols);
 }
 
+int LayoutTableSection::paginationStrutForRow(LayoutTableRow* row, LayoutUnit logicalOffset) const
+{
+    if (row->getPaginationBreakability() == AllowAnyBreaks)
+        return 0;
+    LayoutUnit pageLogicalHeight = pageLogicalHeightForOffset(logicalOffset);
+    if (!pageLogicalHeight)
+        return 0;
+    // If the row is too tall for the page don't insert a strut.
+    LayoutUnit rowLogicalHeight = row->logicalHeight();
+    if (rowLogicalHeight > pageLogicalHeight)
+        return 0;
+    LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(logicalOffset, LayoutBlock::AssociateWithLatterPage);
+    if (remainingLogicalHeight >= rowLogicalHeight)
+        return 0; // It fits fine where it is. No need to break.
+    LayoutUnit paginationStrut = calculatePaginationStrutToFitContent(logicalOffset, remainingLogicalHeight, rowLogicalHeight);
+    if (paginationStrut == remainingLogicalHeight && remainingLogicalHeight == pageLogicalHeight) {
+        // Don't break if we were at the top of a page, and we failed to fit the content
+        // completely. No point in leaving a page completely blank.
+        return 0;
+    }
+    return paginationStrut;
+}
+
 void LayoutTableSection::computeOverflowFromCells()
 {
     unsigned totalRows = m_grid.size();
     unsigned nEffCols = table()->numEffectiveColumns();
     computeOverflowFromCells(totalRows, nEffCols);
 }
 
 void LayoutTableSection::computeOverflowFromCells(unsigned totalRows, unsigned nEffCols)
 {
     unsigned totalCellsCount = nEffCols * totalRows;
@@ skipping 533 matching lines @@
     // FIXME: The table's direction should determine our row's direction, not the section's (see bug 96691).
     if (!style()->isLeftToRightDirection())
         cellLocation.setX(LayoutUnit(table()->effectiveColumnPositions()[table()->numEffectiveColumns()] - table()->effectiveColumnPositions()[table()->absoluteColumnToEffectiveColumn(cell->absoluteColumnIndex() + cell->colSpan())] + horizontalBorderSpacing));
     else
         cellLocation.setX(LayoutUnit(table()->effectiveColumnPositions()[effectiveColumn] + horizontalBorderSpacing));
 
     cell->setLogicalLocation(cellLocation);
 }
 
 } // namespace blink