Objective

Apply the test-driven development approach to solve a problem based on the following specification.

Specification

Method Signature

int add(string numbers)

Description

The add method processes a string of numbers separated by delimiters and returns their sum.

Examples

• Input: "" Output: 0
• Input: "1" Output: 1
• Input: "1,5"Output: 6
• Input: "1\n2,3"Output: 6

Requirements

1. Handling New Lines:

   • The add method should be able to process numbers separated by new lines as well as commas. For instance, the input "1\n2,3" should return a sum of 6.

2. Support for Custom Delimiters:

   • The method should accommodate custom delimiters specified at the beginning of the input string. The format for specifying a custom delimiter is //{delimiter}\n{numbers}. For instance, the input "//;\n1;2", where the delimiter is ";", the output should be 3.

3. Handling Negative Numbers:

   • If the input string contains any negative numbers, the method should throw an exception with the message "Negative numbers are not allowed: <negative_number>".

   • If there are multiple negative numbers, include all of them in the exception message, separated by commas. For example, for the input "1,-2,3,-4", the exception message should be "Negative numbers are not allowed: -2, -4".

Try it

Use the following command to clone this repository, install the required packages, and run the tests.

$ git clone [email protected]:cosmos-lab/test-driven-development.git

$ npm install

$ npm test

Enjoy coding!