private List<Line> processNesting(List<Line> lines) {
int indentSize = -1;
List<Line> lineTree = new ArrayList<Line>();
for (Line line : lines) {
Line parentLine = parentLine(line, lineTree);
if (parentLine != null) {
if (indentSize == -1) {
indentSize = line.leadingWhitespace.length() - parentLine.leadingWhitespace.length();
}
line.indentation = parentLine.indentation + " ";
if (parentLine.isFilter()) {
line.isWithinFilter = true;
}
if (line.isBlank() && !line.isWithinFilter) {
continue;
}