platform-ci/source_checks/jsonc.mjs

// JSONC is used by VS Code configuration. Keep strings intact while removing
// comments and trailing commas; JSON.parse still validates everything else.
export function jsonc(text) {
  let out = '', quoted = false, escaped = false;
  for (let i = 0; i < text.length; i++) {
    const c = text[i], next = text[i + 1];
    if (quoted) {
      out += c;
      if (escaped) escaped = false;
      else if (c === '\\') escaped = true;
      else if (c === '"') quoted = false;
    } else if (c === '"') { quoted = true; out += c; }
    else if (c === '/' && next === '/') {
      while (i < text.length && text[i] !== '\n') i++;
      out += '\n';
    } else if (c === '/' && next === '*') {
      i += 2;
      while (i < text.length && !(text[i] === '*' && text[i + 1] === '/')) {
        out += text[i] === '\n' ? '\n' : ' ';
        i++;
      }
      if (i >= text.length) throw new SyntaxError('Unterminated JSONC comment');
      i++;
      out += ' ';
    } else out += c;
  }
  let clean = '';
  quoted = false; escaped = false;
  for (let i = 0; i < out.length; i++) {
    const c = out[i];
    if (quoted) {
      clean += c;
      if (escaped) escaped = false;
      else if (c === '\\') escaped = true;
      else if (c === '"') quoted = false;
    } else if (c === '"') { quoted = true; clean += c; }
    else if (c !== ',' || !/^\s*[}\]]/.test(out.slice(i + 1))) clean += c;
  }
  return JSON.parse(clean);
}