Currency pipe for Angular that is i18n friendly, used by my CurrencyInputDirective

i18n-currency.pipe.ts

import { CurrencyPipe } from '@angular/common';
import { Pipe, PipeTransform } from '@angular/core';

@Pipe({name: 'appCurrency'})
export class I18NCurrencyPipe extends CurrencyPipe implements PipeTransform {
  constructor() {
    // NOTE: This seemingly doesn't change anything, but is required.
    super('en');
  }

  getCurrencySymbol(): string {
    return this.transform(0, null, 'symbol', '1.0-0').replace('0', '');
  }

  transform(value: any, symbol?: any, showSymbol?: 'code' | 'symbol' | 'symbol-narrow', precision?: string): string | null {
    const localeDataMap: any = {
      'en-US': {
        currency: {
          symbol: 'USD',
          showSymbol: 'symbol',
          digits: {
            rounded: '1.0-0',
            full: '1.2-2'
          }
        }
      }
    };
    const chosenLocal: any = localeDataMap['en-US'];

    // NOTE: Set some defaults that match angular and/or use our defaults from the settings service, if we don't hard code a specific case
    // NOTE: In general an empty string pulls our default from the settings service and no params => $1.23
    symbol = (symbol) ? symbol : chosenLocal.currency.symbol;
    showSymbol = (showSymbol == null) ? chosenLocal.currency.showSymbol : showSymbol;
    precision = (precision == null) ? null : (precision !== '') ? precision : chosenLocal.currency.digits.full;

    return super.transform(value, symbol, showSymbol, precision);
  }
}