Bank Tech Test - Lydia Ntafa

Approaching the task and planning the program:

Reading the specification I have decided that :

• This will be a multi-class program, as it needs to have the ability to store the data in memory.
  • The main class will serve as a BankAccount, it will initialize with 0 balance and it will have public classes for the user to interact with like makeANewTransaction and printStetement.
  • Another class will be named Transaction, every instance of this class will represent a different transaction made (like deposit or withdraw) to manage the data being recorded.
  • The last class will be Statement, and it will be managing the output format and displaying the data to the user.
• The program will be written in JavaScript and will be tested with Jest.

My design process:

Writing the class recipe

1. Created User Stories based on specifications.
2. Created a class diagram using the nouns and verbs extracted from the user stories.
3. Created a sequence diagram to visualize how the classes will interact with each other.
4. Created Examples as Unit Tests

• 3a. Create an example as a unit test
• 3b. encode the example
• 3c. implement the behavior (red-green-refactor)
• 3d. Go back to 3a until all criteria and cases are met

4. Created Examples as integration Tests

• 4a. Create an example as an integration test
• 4b. encode the example
• 4c. implement the behavior (red-green-refactor)
• 4d. Go back to 4a until all criteria and cases are met

5. Run the usage example given in the acceptance criteria to make sure that the specifications are met exactly.

Code Structure:

The class BankAccount has 3 private fields: <#balance> , <#transactions> and <#statements> so every instance of the class starts with those 3 variables initialized to 0 and [], and they can only be accessed and changed within the class.

The class BankAccount has 2 private methods: <#balanceCalculation(amount)> and <#validateAmount(amount)> to help keep the quality of the code high, while ensuring that the sensitive features of the class are secure from misuse.

The class BankAccount has 3 public methods: printStatement(), deposit(amount) and withdraw(amount)

All the transactions made are instances of the class Transaction stored within the <#transactions> array with the date of the transaction that is calculated by obtaining the current date and formatting it as a string using the (English - United Kingdom) locale.

When the user wants to print their bank statement a new instance of the class Statement that includes the transactions stored in the <#transactions> array, at the time, <#transactions> array will be cleared, theinstance will stored in the <#statements> array and the function will return a string

How to Set Up Your Machine to be able to Run this Program

1. Install Node

If you haven't already have Node.js installed on your machine please follow the steps below. First, you will need to install nvm - the Node Version Manager. Running nvm install node and nvm use node will automatically install and use the latest stable version. NVM is distributed using GitHub - you can find installation instructions for the latest version here. You'll need to run a command that looks like this:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.1/install.sh | bash

Once that step is complete, you'll need to reload your ~/.zshrc file:

source ~/.zshrc

Now, you can install Node using nvm:

nvm install node
nvm use node

If the above works, you should see something like this in your terminal (exact versions might be different for you!): Now using node v20.5.0 (npm v9.8.0) - if something went wrong, have a look at the troubleshooting section or reach out to someone for help.

How to Run this Programm and its Tests

1. Run the Program

1. Clone this repository and enter the main directory

git clone https://github.com/LydiaNtafa/BankTechTest.git
cd 

2. You should now be able to type node inside your terminal, to launch the node REPL:

node
Welcome to Node.js v16.6.0.
Type ".help" for more information.
> 

3. Import the class by typing:

const BankAccount = require("./BankAccount");

4. Now you can create new bank accounts. For example:

const Account1 = new BankAccount();
const Account2 = new BankAccount();

Available functions (withdraw(amount), deposit(amount), viewStatement())

for example:

Account2.deposit(100.6);
Account2.printStatement()

OR

Account1.deposit(1000);
Account1.deposit(2000);
Account1.withdraw(500);
Account1.printStatement()

5. type .exit to exit the REPL

Here you can find a Screenshot of Criteria Being Met

2. Run the tests

1. Make sure you are in the main directory of the Project

2. Initialise Dependencies

Make sure you are in the main project directory.

# Initialise the NPM project (this will create a file package.json)
npm init -y

# Add the jest package to our project (this will update package.json and package-lock.json)
npm add jest

# Also install jest "globally" (this is so we can run the `jest` command)
npm install -g jest

3. Run jest inside your terminal

jest

Here you can find a Screenshot of Test Coverage