Function extract_named_arg_name

src/completion/named_args.rs:458–489

If `arg` looks like a named argument (`name: ...`), return the name. Returns `None` for positional arguments.

(arg: &str)

/// If `arg` looks like a named argument (`name: ...`), return the name.
/// Returns `None` for positional arguments.
pub fn extract_named_arg_name(arg: &str) -> Option<String> {
    // Look for `identifier:` at the start (but not `::`)
    let chars: Vec<char> = arg.chars().collect();
    let mut i = 0;

    // Skip whitespace
    while i < chars.len() && chars[i].is_whitespace() {
        i += 1;
    }

    // Read identifier
    let start = i;
    while i < chars.len() && (chars[i].is_alphanumeric() || chars[i] == '_') {
        i += 1;
    }

    if i == start {
        return None;
    }

    // Must be followed by `:` (but not `::`)
    if i < chars.len() && chars[i] == ':' {
        // Check it's not `::`
        if i + 1 < chars.len() && chars[i + 1] == ':' {
            return None;
        }
        let name: String = chars[start..i].iter().collect();
        return Some(name);
    }

    None
}

// ─── Completion Builder ─────────────────────────────────────────────────────