@vectara/vectara-ui/lib/utils/formatDate.js

Vectara's design system, codified as a React and Sass component library

export const formatDate = (date, hasTime = false, showSeconds = true) => {
    const options = {
        year: "numeric",
        month: "long",
        day: "numeric"
    };
    if (hasTime) {
        options.hour = "numeric";
        options.minute = "2-digit";
        if (showSeconds) {
            options.second = "2-digit";
        }
    }
    return Intl.DateTimeFormat(navigator.language, options).format(date);
};