Caesar Cipher solution from The Odin Project

caesar-cipher.rb

def caesar_cipher(text, shift)
  uppercase_bound = 65
  lowercase_bound = 97
  number_of_letters = 26

  secret = text.chars.map do |char|
    if char =~ /[A-Z]/
      char = ((char.ord - uppercase_bound + shift) % number_of_letters + uppercase_bound).chr
    elsif char =~ /[a-z]/
      char = ((char.ord - lowercase_bound + shift) % number_of_letters + lowercase_bound).chr
    end

    char
  end.join("")
end

puts caesar_cipher("What a string!", 5) == "Bmfy f xywnsl!"
puts caesar_cipher("Hey, since you're reading this, please check my postcard collection website at https://ncaron.github.io/world-through-postcards/", 17) == "Yvp, jzetv pfl'iv ivruzex kyzj, gcvrjv tyvtb dp gfjktriu tfccvtkzfe nvsjzkv rk ykkgj://etrife.xzkyls.zf/nficu-kyiflxy-gfjktriuj/"