gridItemSpan function
Detect column span from a UDT node's grid-column style.
Implementation
int gridItemSpan(UDTNode node) {
final style = node.style;
if (style.gridColumnSpan > 1) return style.gridColumnSpan;
if (style.gridColumnEnd > style.gridColumnStart &&
style.gridColumnStart > 0) {
return style.gridColumnEnd - style.gridColumnStart;
}
return 1;
}