import { addYears, formatWithOptions } from 'date-fns/fp' import { eo } from 'date-fns/locale' const addFiveYears = addYears(5) const dateToString = formatWithOptions({ locale: eo }, 'd MMMM yyyy') const dates = [ new Date(2017, 0 /* Jan */, 1), new Date(2017, 1 /* Feb */, 11), new Date(2017, 6 /* Jul */, 2) ] const formattedDates = dates .map(date => dateToString(addFiveYears(date))) .join(', ') console.log(formattedDates === '1 januaro 2022, 11 februaro 2022, 2 julio 2022')