private function _checkBalancesHistory()
 {
     /* check first account balance*/
     $data = $this->_repoBalance->getById([Balance::ATTR_ACCOUNT_ID => $this->acc1[Account::ATTR_ID], Balance::ATTR_DATE => self::DATA_DATE_BALANCE_CHECK]);
     $this->assertEquals(0, $data->getBalanceOpen());
     $this->assertEquals(30, $data->getTotalDebit());
     $this->assertEquals(0, $data->getTotalCredit());
     $this->assertEquals(-30, $data->getBalanceClose());
     /* check second account balance*/
     $data = $this->_repoBalance->getById([Balance::ATTR_ACCOUNT_ID => $this->acc2[Account::ATTR_ID], Balance::ATTR_DATE => self::DATA_DATE_BALANCE_CHECK]);
     $this->assertEquals(0, $data->getBalanceOpen());
     $this->assertEquals(0, $data->getTotalDebit());
     $this->assertEquals(30, $data->getTotalCredit());
     $this->assertEquals(30, $data->getBalanceClose());
     $this->_logger->debug("Balance history (in 'balance' table) is checked.");
 }