This is my resolution of one of exercises mentionned here : https://tddmanifesto.com/exercises/
execute code :
npm run test
Create a simple calculator that takes a String and returns a integer
Signature (pseudo code):
int Add(string numbers)
- The method can take up to two numbers, separated by commas, and will return their sum as a result. So the inputs can be: “”, “1”, “1,2”. For an empty string, it will return 0.
start with the simplest case (empty string) and extend it with the more advanced cases (“1” and “1,2”) step by step keep the three rules in mind and always write just sufficient enough code do not forget to refactor your code after each passing test
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Allow the add method to handle an unknow number of arguments
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Allow the add method to handle newlines as separators, instead of comas
- “1,2\n3” should return “6”
- “2,\n3” is invalid, but no need to clarify it with the program
- Add validation to not to allow a separator at the end
- For example “1,2,” should return an error (or throw an exception)
- Allow the add method to handle a different delimiters
- To change the delimiter, the beginning of the input will contain a separate line that looks like this:
//[delimiter]\n[numbers]
- “//;\n1;3” should return “4”
- “//|\n1|2|3” should return “6”
- “//sep\n2sep5” should return “7”
- “//|\n1|2,3” is invalid and should return an error (or throw an exception) with the message “‘|’ expected but ‘,’ found at position 3.”
STOP HERE if you are a beginner. Continue if you could finish the steps (1-5.) within 30 minutes.
- Calling add with negative numbers will return the message “Negative number(s) not allowed: ”
- “1,-2” is invalid and should return the message “Negative number(s) not allowed: -2”
- “2,-4,-9” is invalid and should return the message “Negative number(s) not allowed: -4, -9”
- Calling add with multiple errors will return all error messages separated by newlines.
- “//|\n1|2,-3” is invalid and return the message “Negative number(s) not allowed: -3\n’|’ expected but ‘,’ found at position 3.”
- Numbers bigger than 1000 should be ignored, so adding 2 + 1001 = 2