Coding kata for the 2018 4yfn event .The following is a TDD Kata, an exercise in coding, refactoring and test-first.
- Try not to read ahead.
- Do one task at a time. The trick is to learn to work incrementally.
- Make sure you only test for correct inputs. There is no need to test for invalid inputs for this kata.
- There are several folders , each one belonging to a specific language or technology in which you can solve the exercise.
- Follow the red-green-refactor approach
-
Please create a separate git branch from master with your solution
git checkout master
git pull origin master
git checkout -b <your_branch_name>
( to create a branch from master). As branch name we suggest you to use your name and surname separated by underscores( e.g. markus_wallace)
-
Commit each one of the requested tasks separately :
git add -u .
git commit -m "<message regarding the task you are solving>"
-
Push your changes :
git push origin <your_branch_name>
- The user and passwords if required will be given at the momment of solving the exercise
Create a simple String calculator with a method int add(String numbers)
.
- The string argument can contain 0, 1 or 2 numbers, and will return their sum (for an empty string it will return 0) for example
""
or"1"
or"1,2"
. - Start with the simplest test case of an empty string and move to one and two numbers.
- Remember to solve things as simply as possible so that you force yourself to write tests you did not think about.
- Remember to refactor after each passing test.
Allow the add()
method to handle an unknown amount of numbers.
Allow the add()
method to handle new lines between numbers (instead of commas).
- the following input is ok:
"1\n2,3"
(will equal 6) - the following input is NOT ok:
"1,\n"
(not need to prove it - just clarifying)
Calling add()
with a negative number will throw an exception "negatives not allowed"
- and the negative that was passed.
For example add("1,4,-1")
should throw an exception with the message "negatives not allowed: -1"
.
If there are multiple negatives, show all of them in the exception message.
Numbers bigger than 1000 should be ignored, so adding 2 + 1001 = 2