Function _cronMatchesParsed

packages/server/src/services/schedule/utils.ts:243–275

* Check whether a pre-parsed cron matches `date`, using a pre-built Intl.DateTimeFormat for TZ conversion. * Both `parsed` and `fmt` should be created once outside any hot loop.

(parsed: _ParsedCronFields, date: Date, fmt: Intl.DateTimeFormat)

 * Both `parsed` and `fmt` should be created once outside any hot loop.
 */
function _cronMatchesParsed(parsed: _ParsedCronFields, date: Date, fmt: Intl.DateTimeFormat): boolean {
    let minute: number, hour: number, dom: number, month: number, dow: number, year: number
    try {
        const parts = fmt.formatToParts(date)
        const get = (type: string) => parseInt(parts.find((p) => p.type === type)?.value ?? '0', 10)
        const weekdayStr = parts.find((p) => p.type === 'weekday')?.value ?? 'Sun'
        minute = get('minute')
        hour = get('hour') % 24
        dom = get('day')
        month = get('month')
        year = get('year')
        dow = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'].indexOf(weekdayStr)
        if (dow === -1) dow = date.getUTCDay()
    } catch {
        minute = date.getUTCMinutes()
        hour = date.getUTCHours()
        dom = date.getUTCDate()
        month = date.getUTCMonth() + 1
        year = date.getUTCFullYear()
        dow = date.getUTCDay()
    }
    // Last day of the (TZ-local) month: `new Date(year, month, 0)` rolls to the last day of `month`
    // because day 0 of the next month equals the last day of the current month.
    const lastDay = new Date(year, month, 0).getDate()
    const dowMatches = _matchCronField(parsed.dowField, dow, 0) || (dow === 0 && _matchCronField(parsed.dowField, 7, 0))
    return (
        _matchCronField(parsed.minuteField, minute, 0) &&
        _matchCronField(parsed.hourField, hour, 0) &&
        _matchDomField(parsed.domField, dom, lastDay) &&
        _matchCronField(parsed.monthField, month, 1) &&
        dowMatches
    )
}

/**
 * Computes the next Date after `after` (defaults to now) when the cron expression will fire.