import { endOfDecade } from "https://deno.land/x/date_fns@v2.5.1/index.js";
Examples
// The end of a decade for 12 May 1984 00:00:00:
var result = endOfDecade(new Date(1984, 4, 12, 00, 00, 00))
//=> Dec 31 1989 23:59:59.999
// The end of a decade for 12 May 1984 00:00:00: var result = endOfDecade(new Date(1984, 4, 12, 00, 00, 00)) //=> Dec 31 1989 23:59:59.999