• The fizzbuzz generation is mixed in with its reporting. Code written this way breaks the single responsibility principle and as such may be harder to test, reason about, and change.
• When I exercise the FizzBuzz with an invalid range of (start: 1, end: 0), I get "false" on the console, which doesn't tell me what I did wrong and forces me to read the code to find out.
• Test should have more descriptive titles like "decimal numbers are not allowed" instead of "fizzbuzz 3 16.5 returns".

Node.js and npm

Navigate to desired Step:

$ cd src/Step1

Run program:

$ node fizzbuzz 2 12

Install Jest:

$ npm install

Run all Test Suites:

$ npm test