kornelrabczak / bank-kata-scala

Bank account kata

Bank account kata

Bank kata

Test scenario

Given a client makes a deposit of 1000 on 10-01-2012
And a deposit of 2000 on 13-01-2012
And a withdrawal of 500 on 14-01-2012
When she prints her bank statement
Then she would see
date || credit || debit || balance
14/01/2012 || || 500.00 || 2500.00
13/01/2012 || 2000.00 || || 3000.00
10/01/2012 || 1000.00 || || 1000.00

Requirements

• Deposit and Withdrawal
• Transfer
• Account statement [](date, amount, balance)
• Statement printing
• Statement filters (just deposits, withdrawal, date)

Query:

• Bank statement ( list of all transactions and the balance after each one )

Commands:

• Deposit
• Withdraw
• Transaction

Pseudo code

type AccountId = String
type Money = BigDecimal
type Transaction = (account: AccountId, date: Date, amount: Money)
type AccountStatement = (transaction: Transaction, balance: Money)
type Transfer = (fromAccount, transaction) -> (fromAccount, transaction) -> Unit

deposit: Bank -> Transaction -> Unit
withdraw: Bank -> Transaction -> Unit
statement: Bank -> AccountId -> foldLeft [AccountStatement]

type Terminal: List[AccountStatement] => String
printing: Terminal -> AccountId -> List[AccountStatement]
consolePrinting: AccountId -> List[AccountStatement] = printing(std out) _