jackwener/OpenCLI · error · ArgumentError

--return (${ret}) must be on or after --depart (${depart})

Error message

--return (${ret}) must be on or after --depart (${depart})

What it means

An ArgumentError raised when the parsed --return date is earlier than the parsed --depart date. Both dates go through parseIsoDate first, so this compares normalized ISO strings (YYYY-MM-DD lexicographic comparison is chronologically correct). A round-trip search cannot return before it departs.

Source

Thrown at clis/ctrip/flight-round.js:74

    ],
    columns: [
        'rank',
        'airline', 'flightNo', 'aircraft',
        'departureTime', 'departureAirport',
        'arrivalTime', 'arrivalAirport', 'terminal',
        'price', 'currency', 'cabin',
        'url',
    ],
    func: async (page, kwargs) => {
        const fromCode = parseIataCode('from', kwargs.from);
        const toCode = parseIataCode('to', kwargs.to);
        if (fromCode === toCode) {
            throw new ArgumentError(`--from and --to must differ (got ${fromCode})`);
        }
        const depart = parseIsoDate('depart', kwargs.depart);
        const ret = parseIsoDate('return', kwargs.return);
        if (ret < depart) {
            throw new ArgumentError(`--return (${ret}) must be on or after --depart (${depart})`);
        }
        const limit = parseListLimit(kwargs.limit);

        const searchUrl =
            `https://flights.ctrip.com/online/list/round-${fromCode.toLowerCase()}-${toCode.toLowerCase()}` +
            `?depdate=${depart}_${ret}&cabin=Y_S_C_F&adult=1&child=0&infant=0`;
        await page.goto(searchUrl);
        const waitResult = await page.evaluate(WAIT_FOR_FLIGHTS_ROUND_JS);
        if (waitResult === 'captcha') {
            throw new AuthRequiredError('flights.ctrip.com', 'Ctrip is asking for a captcha; complete it in your browser session and retry');
        }
        if (waitResult !== 'content') {
            throw new CommandExecutionError(`Ctrip round-trip flight page did not render flight cards (state=${String(waitResult)})`);
        }
        const renderedCardCount = await page.evaluate(buildScrollUntilJs(ROUND_CARD_SELECTOR, limit));
        const raw = await page.evaluate(buildFlightExtractJs(ROUND_CARD_SELECTOR, false));
        if (!Array.isArray(raw)) {
            throw new CommandExecutionError('Ctrip round-trip flight DOM extraction returned malformed rows');

View on GitHub (pinned to 49907e53dc)

Solutions

1. Swap or correct the dates so --return is on or after --depart.
2. Validate the pair in your calling code before invoking the CLI.
3. If the return date is computed, check the timezone/arithmetic that produced it.
4. Note the error message includes both dates — verify which one is wrong against the logged values.

Example fix

// before
cli(['flight-round', '--depart', ret, '--return', dep]);
// after
cli(['flight-round', '--depart', dep, '--return', ret]); // ret >= dep validated before call

function validateRoundTrip(depart, ret) {
  const iso = /^\d{4}-\d{2}-\d{2}$/;
  if (!iso.test(depart) || !iso.test(ret)) throw new Error('dates must be YYYY-MM-DD');
  if (ret < depart) throw new Error(`--return (${ret}) must be on or after --depart (${depart})`);
}

function isOnOrAfter(ret, depart) { return /^\d{4}-\d{2}-\d{2}$/.test(ret) && /^\d{4}-\d{2}-\d{2}$/.test(depart) && ret >= depart; }

try { await cli(['flight-round','--depart',dep,'--return',ret]); } catch (e) { if (e instanceof ArgumentError && e.message.includes('--return')) { logDateValidationError(dep, ret); } else throw e; }

When it happens

Trigger: Calling flight-round with a return date strictly before the depart date, e.g. `--depart 2026-03-10 --return 2026-03-05`.

Common situations: Mixing up argument order in scripts or positional args; computing the return date from the wrong base variable; timezone bugs that shift a computed return date a day backward; user input where the user thinks of depart/return reversed.

Related errors

• --from and --to must differ (got ${fromCity})
• --from and --to must differ (got ${fromCode})
• <train-no> "${trainNo}" does not look like a 12306 internal
• --from station must not be empty
• --to station must not be empty

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/539d35adbbd3889f. Report an issue: GitHub.