Function formatExpiryInput

static/js/payment.js:370–376

(month, year)

}

function formatExpiryInput(month, year) {
    const mm = normalizeMonth(month);
    const rawYear = String(year || "").replace(/\D/g, "");
    const yy = rawYear ? rawYear.slice(-2) : "";
    if (!mm && !yy) return "";
    return yy ? `${mm}/${yy}` : mm;
}

function parseExpiryInput(value) {
    const raw = String(value || "").trim();