affaan-m/ECC · error · Error

${flagName} requires a value

Error message

${flagName} requires a value

What it means

Thrown by readArgValue in preview-pack-smoke's arg parser when a value-taking flag (--format, --root) is followed by nothing or by another `--` flag. Same guard pattern as the other ECC scripts: a missing/flag-like value is rejected so the smoke gate never silently treats a flag name as data. This script is the deterministic smoke gate for the ECC 2.0 rc.1 preview pack.

Source

Thrown at scripts/preview-pack-smoke.js:97

];

function usage() {
  console.log([
    'Usage: node scripts/preview-pack-smoke.js [--format <text|json>] [--root <dir>]',
    '',
    'Deterministic smoke gate for the ECC 2.0 rc.1 preview pack.',
    '',
    'Options:',
    '  --format <text|json>  Output format (default: text)',
    '  --root <dir>          Repository root to inspect (default: cwd)',
    '  --help, -h            Show this help',
  ].join('\n'));
}

function readArgValue(args, index, flagName) {
  const value = args[index + 1];
  if (!value || value.startsWith('--')) {
    throw new Error(`${flagName} requires a value`);
  }
  return value;
}

function parseArgs(argv) {
  const args = argv.slice(2);
  const parsed = {
    format: 'text',
    help: false,
    root: path.resolve(process.cwd()),
  };

  for (let index = 0; index < args.length; index += 1) {
    const arg = args[index];

    if (arg === '--help' || arg === '-h') {
      parsed.help = true;
      continue;

View on GitHub (pinned to 01e15490f0)

Solutions

1. Provide the value right after the flag: `--format json` or `--root /repo`.
2. Prefer the `=` form for safety: `--format=json`, `--root=/repo`.
3. Validate any templated value is non-empty before assembling the command.

Example fix

# before
node scripts/preview-pack-smoke.js --root --format json
# after
node scripts/preview-pack-smoke.js --root /path/to/repo --format json

function ensurePreviewFlagValue(args, index, flagName) {
  const value = args[index + 1];
  if (!value || value.startsWith('--')) {
    throw new Error(`${flagName} requires a value`);
  }
  return value;
}

function isFlagValueToken(token) {
  return typeof token === 'string' && token.length > 0 && !token.startsWith('--');
}

try {
  parseArgs(process.argv);
} catch (err) {
  if (err.message.endsWith('requires a value')) {
    console.error(`${err.message}. Use --flag=value form for safety.`);
    process.exit(2);
  }
  throw err;
}

When it happens

Trigger: `--format` as the last token; `--root --format json` (root value missing); a wrapper that conditionally appends a value that resolved empty.

Common situations: CI matrix builds the command from templates and a variable was empty; user edited an example and deleted the value.

Related errors

• Unknown argument: ${arg}
• Invalid format: ${parsed.format}. Use text or json.
• Unknown argument: ${arg}
• Unknown argument: ${arg}
• --timeout-ms must be a positive number

AI-assisted analysis of affaan-m/ECC@01e15490f0 (2026-08-13). Data as JSON: /api/errors/65f8d1b1389817bf. Report an issue: GitHub.