@Test
public void handleBuyTransactionStartedEvent() {

    testSubject.on(new BuyTransactionStartedEvent(transactionIdentifier,
                                                  orderBookIdentifier,
                                                  portfolioIdentifier,
                                                  DEFAULT_TOTAL_ITEMS,
                                                  DEFAULT_ITEM_PRICE));
    verify(transactionViewRepository).save(argThat(new TransactionEntryMatcher(
            DEFAULT_TOTAL_ITEMS, 0, DEFAULT_COMPANY_NAME, DEFAULT_ITEM_PRICE, STARTED, BUY
    )));
}