@leanup/cli/template/src/shares/filters.ts

const CURRENCY_FORMATTER: Intl.NumberFormat = new Intl.NumberFormat('de-DE', {
  currency: 'EUR',
  maximumFractionDigits: 2,
  minimumFractionDigits: 2,
});

/**
 * https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat
 *
 * Missing config for leading 0's 1.1.1970 instead of 01.01.1970
 */
const DATE_FORMATTER: Intl.DateTimeFormat = new Intl.DateTimeFormat('de-DE');

export class Filters {
  public static currency(value: number): string {
    if (isNaN(value) === false && typeof value === 'number') {
      return CURRENCY_FORMATTER.format(value);
    } else {
      throw new Error('Value is not a number!');
    }
  }

  public static date(value: Date): string {
    if (value instanceof Date) {
      return DATE_FORMATTER.format(value);
    } else {
      throw new Error('Value is not a date!');
    }
  }
}