Function split_top_level_parens

nodedb-spatial/src/wkt.rs:221–241

Split by commas at the top level of parentheses nesting. "(...), (...)" → ["(...)", "(...)"]

(s: &str)

/// Split by commas at the top level of parentheses nesting.
/// "(...), (...)" → ["(...)", "(...)"]
fn split_top_level_parens(s: &str) -> Option<Vec<String>> {
    let mut parts = Vec::new();
    let mut depth = 0;
    let mut start = 0;

    for (i, ch) in s.char_indices() {
        match ch {
            '(' => depth += 1,
            ')' => depth -= 1,
            ',' if depth == 0 => {
                parts.push(s[start..i].to_string());
                start = i + 1;
            }
            _ => {}
        }
    }
    if start < s.len() {
        parts.push(s[start..].to_string());
    }
    if parts.is_empty() { None } else { Some(parts) }
}

/// Split geometry collection items by top-level commas, handling nested parens.
fn split_top_level_items(s: &str) -> Vec<String> {