jackwener/OpenCLI · error · ArgumentError

--${name} must be a 3-letter IATA code, got ${JSON.stringify

Error message

--${name} must be a 3-letter IATA code, got ${JSON.stringify(raw)}

What it means

parseIataCode validates a CLI argument as a 3-letter IATA airport/city code (e.g. LON, NYC). This error is thrown when the value is provided but is not exactly three uppercase ASCII letters after trimming and uppercasing. It is an ArgumentError meant to give the CLI user immediate, actionable feedback.

Source

Thrown at clis/trip/utils.js:23

 * results client-side, so the browser-mode commands read the rendered DOM.
 * Flight rows are `.result-item` cards keyed by stable `data-testid` anchors
 * (`flights-name`, `stopInfoText`, `flight_price_*`).
 */
import { ArgumentError, CommandExecutionError } from '@jackwener/opencli/errors';

const MIN_LIMIT = 1;
const MAX_LIMIT = 50;
const ISO_DATE_RE = /^(\d{4})-(\d{2})-(\d{2})$/;
const POI_SEARCH_ENDPOINT = 'https://www.trip.com/restapi/soa2/14427/poiSearch';
const PACKAGE_SEARCH_ENDPOINT = 'https://www.trip.com/restapi/soa2/19866/FlightSelectSearch';

export function parseIataCode(name, raw) {
    if (raw === undefined || raw === null || raw === '') {
        throw new ArgumentError(`--${name} is required (3-letter IATA code, e.g. LON, NYC)`);
    }
    const value = String(raw).trim().toUpperCase();
    if (!/^[A-Z]{3}$/.test(value)) {
        throw new ArgumentError(`--${name} must be a 3-letter IATA code, got ${JSON.stringify(raw)}`);
    }
    return value;
}

export function parseIsoDate(name, raw) {
    if (raw === undefined || raw === null || raw === '') {
        throw new ArgumentError(`--${name} is required (YYYY-MM-DD)`);
    }
    const value = String(raw).trim();
    const m = ISO_DATE_RE.exec(value);
    if (!m) {
        throw new ArgumentError(`--${name} must be YYYY-MM-DD, got ${JSON.stringify(raw)}`);
    }
    const year = Number(m[1]);
    const month = Number(m[2]);
    const day = Number(m[3]);
    if (month < 1 || month > 12 || day < 1 || day > 31) {
        throw new ArgumentError(`--${name} has invalid month/day: ${value}`);

View on GitHub (pinned to 49907e53dc)

Solutions

  1. Pass a valid 3-letter IATA code, e.g. --from LON --to NYC
  2. If passing a city name, map it to its IATA code first (via airport lookup/search tooling)
  3. Quote shell arguments so spaces don't split them, and ensure no trailing whitespace or stray characters
  4. Check that the variable you interpolate actually contains the code, not an empty string, number, or object

Example fix

// before
clis-trip flights --from London --to NYC
// after
clis-trip flights --from LON --to NYC
Defensive patterns

Strategy: validation

Validate before calling

function isValidIata(v) {
  return typeof v === 'string' && /^[A-Z]{3}$/.test(v.trim().toUpperCase());
}
if (!isValidIata(from)) throw new Error(`--from must be a 3-letter IATA code, got ${JSON.stringify(from)}`);

Type guard

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

Try / catch

import { ArgumentError } from 'clis/trip/utils.js';
try {
  runTripCli(['flights', '--from', from, '--to', to]);
} catch (err) {
  if (err instanceof ArgumentError && /must be a 3-letter IATA code/.test(err.message)) {
    console.error(`Bad airport code: ${err.message}. Use codes like LON, NYC.`);
    process.exitCode = 2;
  } else throw err;
}

Prevention

When it happens

Trigger: Calling fromCode, toCode, or airport (which delegate to parseIataCode) with a value that, after String(raw).trim().toUpperCase(), fails /^[A-Z]{3}$/ — e.g. 'London', 'lo', 'LON ', 'L1A', numeric 123, or arrays/objects.

Common situations: Users type full city names ('London') instead of IATA codes; shell expands a value into multiple tokens ('NYC LON'); a variable is empty or contains a number; copy-pasted code includes trailing punctuation.

Understand the failure class

Background: "Unknown argument", "Invalid value", and "must be one of": invalid CLI argument errors explained — this error's family across 35 libraries.

Related errors

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/1f62df7dcae08acf. Report an issue: GitHub.