Function blankCTypeKeywordArgs

src/extraction/languages/c-cpp.ts:1270–1340

(source: string)

const C_TYPE_ARG_OPENER_RE = /^(struct|union|enum)([ \t\r\n]+)([A-Za-z_]\w*)([ \t\r\n]*\*+)?(?=[ \t\r\n]*[,)])/;
const C_TYPE_ARG_SCAN_CAP = 600;
export function blankCTypeKeywordArgs(source: string): string {
  if (!/\b(?:struct|union|enum)[ \t\r\n]/.test(source)) return source;
  let chars: string[] | null = null;
  C_TYPE_ARG_HEAD_RE.lastIndex = 0;
  let m: RegExpExecArray | null;
  while ((m = C_TYPE_ARG_HEAD_RE.exec(source)) !== null) {
    const head = m[1] as string;
    if (C_TYPE_ARG_HEAD_EXCLUSIONS.has(head)) continue;
    // Reject declaration shapes: an identifier or `*` (a return/field type)
    // immediately before the head — unless that word is `return`.
    let j = m.index - 1;
    while (j >= 0 && (source[j] === ' ' || source[j] === '\t')) j--;
    const prev = j >= 0 ? (source[j] as string) : '';
    if (/[\w*]/.test(prev)) {
      let w = j;
      while (w >= 0 && /\w/.test(source[w] as string)) w--;
      if (source.slice(w + 1, j + 1) !== 'return') continue;
    }
    const open = m.index + (m[0] as string).length - 1;
    let depth = 1;
    let atArgStart = true;
    for (let k = open + 1; k < source.length && k - open <= C_TYPE_ARG_SCAN_CAP; k++) {
      const ch = source[k] as string;
      if (ch === '"' || ch === "'") {
        const quote = ch;
        k++;
        while (k < source.length && source[k] !== quote) {
          if (source[k] === '\\') k++;
          k++;
        }
        atArgStart = false;
        continue;
      }
      if (ch === ' ' || ch === '\t' || ch === '\n' || ch === '\r') continue;
      if (ch === '(') {
        depth++;
        atArgStart = false;
        continue;
      }
      if (ch === ')') {
        depth--;
        if (depth === 0) break;
        atArgStart = false;
        continue;
      }
      if (ch === ';' || ch === '{' || ch === '}') break; // not an argument list
      if (ch === ',') {
        if (depth === 1) atArgStart = true;
        continue;
      }
      if (depth === 1 && atArgStart) {
        const opener = C_TYPE_ARG_OPENER_RE.exec(source.slice(k, k + 160));
        if (opener) {
          chars ??= [...source];
          const kw = opener[1] as string;
          for (let b = k; b < k + kw.length; b++) chars[b] = ' ';
          if (opener[4]) {
            const tail = opener[4] as string;