Format JS Date in ISO-8601 without timezone issues

date-format.test.js

test.each`
    dateStr                                  |   result
    ${'December 17, 1995 03:24:00'}          |   ${'1995-12-17'}
    ${'March 5, 1998 03:24:00'}              |   ${'1998-03-05'}
    ${'1995-12-17T03:24:00'}                 |   ${'1995-12-17'}
    ${628021800000}                          |   ${'1995-12-17'}
`('returns friendly date', ({ dateStr, result }) => {
    expect(
        getFriendlyDate(new Date(dateStr))
    ).toEqual(result)
})

format-js-date.md

Format JS Date in ISO-8601 without timezone issues

The following function provides an easy way to format Javascript dates in ISO-8601 format without using date.toISOString(), which could lead to timezone issues as the date is first converted to UTC which could lead to discrepancies in the result in certain timezones.

/**
 * Formats the provided date in _ISO-8601 format_ without using
 * `toISOString()` to avoid timezone issues
 *
 * @param date The Date object
 * @returns {string}
 */
function formatDate(date) {
    return [
        `${date.getFullYear()}`,
        `${date.getMonth() + 1}`.padStart(2, '0'),
        `${date.getDate()}`.padStart(2, '0')
    ].join('-')
}