jackwener/OpenCLI · error · ArgumentError

currency must be a 3-letter ISO code (e.g. USD, JPY, CNY), g

Error message

currency must be a 3-letter ISO code (e.g. USD, JPY, CNY), got ${JSON.stringify(value)}

What it means

normalizeCurrency validates the optional currency parameter as a 3-letter A-Z code (uppercased and trimmed first). It throws ArgumentError when a non-empty currency value is not exactly three letters after normalization. It does not validate ISO-4217 membership — only the shape — so '' or null are allowed (meaning default) but 'US' or 'USDD' are rejected.

Source

Thrown at clis/booking/search.js:59

  }
  const [year, month, day] = v.split('-').map(Number);
  const d = new Date(Date.UTC(year, month - 1, day));
  if (
    Number.isNaN(d.getTime()) ||
    d.getUTCFullYear() !== year ||
    d.getUTCMonth() !== month - 1 ||
    d.getUTCDate() !== day
  ) {
    throw new ArgumentError(`${label} is not a valid calendar date: ${v}`);
  }
  return v;
}

function normalizeCurrency(value) {
  if (value == null || value === '') return '';
  const v = String(value).trim().toUpperCase();
  if (!/^[A-Z]{3}$/.test(v)) {
    throw new ArgumentError(`currency must be a 3-letter ISO code (e.g. USD, JPY, CNY), got ${JSON.stringify(value)}`);
  }
  return v;
}

const ALLOWED_LANGS = new Set([
  'en-us', 'en-gb', 'zh-cn', 'zh-tw', 'ja', 'ko', 'de', 'fr', 'es', 'it',
  'pt-br', 'pt-pt', 'ru', 'th', 'vi', 'tr', 'pl', 'nl', 'ar',
]);

function normalizeLang(value) {
  if (value == null || value === '') return '';
  const v = String(value).trim().toLowerCase();
  if (!ALLOWED_LANGS.has(v)) {
    throw new ArgumentError(`lang must be one of: ${[...ALLOWED_LANGS].join(', ')}`);
  }
  return v;
}

View on GitHub (pinned to 49907e53dc)

Solutions

Change the value to the 3-letter ISO 4217 code, e.g. 'USD', 'JPY', 'CNY'
Trim surrounding whitespace and remove symbols from the config/env value
Validate shape with /^[A-Za-z]{3}$/ before calling
Check the source system is not emitting numeric ISO codes and map 840 -> USD if so

Example fix

// before
const currency = '$';
await search(page, { destination: 'Tokyo', currency });
// after
const currency = 'USD';
await search(page, { destination: 'Tokyo', currency });

Defensive patterns

Strategy: type-guard

Validate before calling

function normalizeCurrencySafe(v) {
  if (v == null || v === '') return '';
  const s = String(v).trim().toUpperCase();
  if (!/^[A-Z]{3}$/.test(s)) throw new Error(`bad currency: ${v}`);
  return s;
}

Type guard

function isCurrencyCode(v) {
  return typeof v === 'string' && /^[A-Za-z]{3}$/.test(v.trim());
}

Try / catch

try {
  await search(page, { destination, currency });
} catch (e) {
  if (/3-letter ISO code/.test(e.message)) {
    throw new Error(`Set currency to a 3-letter ISO code like USD; got: ${currency}`);
  } else throw e;
}

Prevention

Store alphabetic ISO 4217 codes ('USD'), never symbols or names
Uppercase and trim currency values at the config boundary
Map numeric ISO codes to alphabetic ones if your source uses them
Keep currency as an optional field only when defaults are acceptable

When it happens

Trigger: Passing currency values like 'US', 'us-dollar', '$', 'USDollar', or numbers to the search command; a config value that contains a currency symbol or full currency name instead of the code.

Common situations: Using '$' or '€' from UI input; storing 'US Dollar' in a settings file; concatenating a numeric code (840) instead of the alphabetic code; trailing whitespace/full-width characters in config.

Related errors

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/14c3671d80c2bde4. Report an issue: GitHub.