* Test enlarge block when there's no nodes to enlarge.
// nodes to enlarge( #4073 ).
// It's the body which stop the enlarging if no block boundary found.
// the document position of it with 'enlargeable' node.
( !enlargeable || blockBoundary.contains( enlargeable ) ) ?
|| blockBoundary.equals( enlargeable ) ) ?
// End the range right before the block boundary node.