Code Explanation

StringCalculator Class

• The StringCalculator class has a method called add that accepts a string containing numbers. The method processes the string to return the sum of the numbers, considering different delimiter formats.

Run Tests:

• Now you can run the tests using RSpec. To run all the tests, use the following command:
• Prerequisites: Ensure you have RSpec installed. If it's not installed, run the following command: gem install rspec
• To run all the tests in the spec folder, use the following command: rspec spec/string_calculator_spec.rb

Key Features:

• Empty string: If the input string is empty, the method returns 0.
• Single number: If the string contains just one number, it returns that number.
• Comma-separated numbers: The default behavior is to split numbers by commas and return their sum.
• Newline-separated numbers: The string can contain newlines between numbers, and they are treated the same as commas.
• Custom delimiters: Custom delimiters can be defined at the start of the string, using a format like //[delimiter], and the string will be split by the specified delimiter(s).
• Numbers greater than 1000: Numbers greater than 1000 are ignored in the sum.
• StringCalculator#add Method
• The method first checks if the string starts with a custom delimiter declaration (using //).
• If a custom delimiter is provided, the method extracts it and uses it to split the numbers.
• If no custom delimiter is provided, it defaults to splitting the string by commas and newlines.
• The method then filters out any numbers greater than 1000 and returns the sum of the remaining numbers.