TobiasRoland / bank-kata-bootstrap

Bootstrap for TDD bank kata (or any kata, really)

bank-kata-bootstrap

Bootstrap for TDD bank kata (or any kata, really)

Kata: a Japanese word, meaning literally: "form" (型 or 形): “a detailed choreographed pattern of movements made to be practiced alone, but are also practiced within groups and in unison when training.”

Problem Description

• Deposit into the Account
• Withdraw from the Account
• Print the account statement

Statement should have following format:

> DATE       | AMOUNT  | BALANCE
> 10/04/2019 | 100.00  | 900.00
> 09/04/2019 | -200.00 | 800.00
> 01/01/2019 | 1000.00 | 1000.00

Constraints

1. Start with class with follwing structure:

Public class Account {
   public void deposit(int amount) {}
   public void withdraw(int amount) {}
   public void printStatement() {}
}

2. You are not allowed to add/change any other public methods or public fields to the class – apart from a constructor

3. Use strings and integers for dates and amounts (keep it simple)

4. Don’t worry about spacing in the printed statements

TDD Constraints

1. You are not allowed to write a single line of implementation code unless there’s a test for it

2. If you think of an edge case, make a test, then go back and refactor till it works.

Tips

• Think -> Test -> Implement

• Red -> Green -> Refactor -> GOTO Red

• Wrap IO calls with your own Console that you can stub and verify against

• Your Account will probably need a Ledger, containing all the Transactions

• Use your testing library of choice; Mockito and Assert4J is probably the java weapon of choice for this.

• If you feel really confident, start by writing an acceptance test against the Account