fizzbuzz.rb

# fizzbuzz.rb
def fizzbuzz(number)
  return "FizzBuzz" if number % 3 == 0 && number % 5 == 0
  return "Fizz" if number % 3 == 0
  return "Buzz" if number % 5 == 0
  number
end

# fizzbuzz_spec.rb
require './fizzbuzz'

RSpec.describe 'FizzBuzz' do
  it "returns 'Fizz' when divisible by 3" do
    expect(fizzbuzz(3)).to eq('Fizz')
    expect(fizzbuzz(6)).to eq('Fizz')
  end

  it "returns 'Buzz' when divisible by 5" do
    expect(fizzbuzz(5)).to eq('Buzz')
    expect(fizzbuzz(10)).to eq('Buzz')
  end

  it "returns 'FizzBuzz' when divisible by both 3 and 5" do
    expect(fizzbuzz(15)).to eq('FizzBuzz')
    expect(fizzbuzz(30)).to eq('FizzBuzz')
  end

  it "returns the number when not divisible by 3 or 5" do
    expect(fizzbuzz(1)).to eq(1)
    expect(fizzbuzz(4)).to eq(4)
    expect(fizzbuzz(7)).to eq(7)
  end
end