@Test
public void get() throws Exception {

    when(trip.getDefaultCurrencyCode()).thenReturn("trip");
    when(price.getCurrencyCode()).thenReturn("receipt");
    final ReceiptCurrencyCodeSupplier nullReceiptSupplier = new ReceiptCurrencyCodeSupplier(trip, receiptInputCache, null);
    final ReceiptCurrencyCodeSupplier validReceiptSupplier = new ReceiptCurrencyCodeSupplier(trip, receiptInputCache, receipt);
    assertEquals(nullReceiptSupplier.get(), "trip");
    assertEquals(validReceiptSupplier.get(), "receipt");
    when(receiptInputCache.getCachedCurrency()).thenReturn("cache");
    final ReceiptCurrencyCodeSupplier nullReceiptSupplierWithCachedCurrency = new ReceiptCurrencyCodeSupplier(trip, receiptInputCache, null);
    assertEquals(nullReceiptSupplierWithCachedCurrency.get(), "cache");
}