Bank Tech Test

This is a program allowing the user to input deposit amounts and withdrawal amounts. The program then returns a statement providing the date of transaction, amount deposited or withdrawn, and account balance.

The original specification for this tech test can be found here.

1. Approach

My priority for this program was to write clean, readable, reusable code. I followed a TDD approach from the start, writing behaviour-driven tests before the code itself. This program evolved from two classes to three as I chose to create the Transaction class, using dependency injection to ensure separation of concerns. Once all tests were passing and the program was functional, I then began refactoring the classes and test suites to uphold the DRY principle.

The program is structured into three classes with their respective responsibilities as follows:

• Transaction: represents a single transaction, storing its date, type (credit or debit), amount and balance
• BankAccount: represents a bank account that handles deposits and withdrawals (by saving them as transactions and updating the account balance)
• BankStatement: responsible for printing a bank statement

2. Installation

First, clone this repo by running the command below in terminal.

git clone https://github.com/mirandaweston/bank-tech-test.git

Then, you will need to install Node.js dependencies by running the following command.

npm install

3. Run

In order to run the program, navigate to the src directory by running cd src and then run node to enter Node.js.

You can now start banking! Below is an example of the program running in terminal.

Welcome to Node.js v19.5.0.
Type ".help" for more information.
> const BankAccount = require('./bank_account');
undefined
> const BankStatement = require('./bank_statement');
undefined
> const account = new BankAccount();
undefined
> const statement = new BankStatement(account.transactions);
undefined
> account.deposit(1000);
undefined
> account.deposit(2000);
undefined
> account.withdraw(500);
undefined
> statement.print();
date || credit || debit || balance
21/03/2023 || || 500.00 || 2500.00
21/03/2023 || 2000.00 || || 3000.00
21/03/2023 || 1000.00 || || 1000.00

4. Testing

Run the following command to ensure you are in the right directory:

cd bank-tech-test

To run all test suites:

npm test

To run the test suite for the BankAccount class only:

npm test bank_account_test.js

To run the test suite for the BankStatement class only:

npm test bank_statement_test.js

To run the test suite for the Transaction class only:

npm test transaction_test.js

5. Test coverage: 100%