String Calculator TDD Kata

Overview

This repository contains a solution for the String Calculator TDD Kata, designed to practice Test-Driven Development (TDD) using JavaScript. The calculator can handle addition of numbers provided in a string format with various delimiter options.

Features

• Empty String: Returns 0.
• Single Number: Returns the number itself.
• Two Numbers: Returns the sum of two numbers separated by a comma.
• Multiple Numbers: Handles any number of comma-separated or newline-separated numbers.
• Custom Delimiters: Supports custom delimiters specified in the format //[delimiter]\n[numbers…], including special and multi-character delimiters.
• Negative Numbers: Throws an exception with a message listing all negative numbers.

Installation

1. Clone the repository:

   git clone https://github.com/yourusername/your-repository.git
   cd your-repository
   npm install

2. Navigate to the project directory: cd your-repository
3. Install dependencies: npm install

Usage

To use the add function, you can call it with a string input as described in the features. For example:

const add = require('./calculator');

// Examples
console.log(add("")); // Outputs: 0
console.log(add("1")); // Outputs: 1
console.log(add("1,2")); // Outputs: 3
console.log(add("//;\n1;2")); // Outputs: 3
console.log(add("//[***]\n1***2***3")); // Outputs: 6

Running Tests

To ensure that everything is working correctly, run the test suite using:

npx jest

Test cases

The test cases cover the following scenarios:

Empty string
Single number
Two numbers
Multiple numbers
New lines as delimiters
Custom delimiters
Negative numbers