Mini Projects - Phone Number Formatter

app.rb

# app.rb

require "./phone_number_formatter.rb"

puts "What's your phone number?"

number_input = gets.chomp

test = PhoneNumber.new(number_input)

puts "That's #{test.number}, right?"

phone_number_formatter.rb

# Phone Number Formatter

class PhoneNumber

  attr_accessor :number

  # When the object is initialized, it takes one argument.
  #
  # number_input - string
  #
  # Runs the format_number method using the number_input as the argument
  def initialize(number_input)
    format_number(number_input)
  end


  # Changes the input to the correct format.
  #
  # Uses the substitution method to manipulate the number_input. Finds a pattern
  #   using regex. Pattern looks for a group of three digits, then a group of
  #   three digits, then a group of four digits. It then substitutes that
  #   pattern with parentheses, inside the parentheses it puts the regex group 1
  #   followed by a space character, then regex group 2, then a dash, and then
  #   the regex group three pattern.
  #
  # Returns and stores the result as an instance variable.
  def format_number(number_input)
    @number = number_input.sub(/(\d{3})(\d{3})(\d{4})/,'(\1) \2-\3')
  end

end

phone_number_formatter_test.rb

# Phone Number Formatter Test
require "minitest/autorun"
require_relative "phone_number_formatter.rb"

class PhoneNumberFormatterTest < Minitest::Test

  # Need to test the format number method to ensure the inputted String returns
  #   a properly formatted String to look like a phone number.
  def test_phone_number_formatter
    number = PhoneNumber.new("1234567890")

    assert_equal("(123) 456-7890", number.format_number("1234567890"))
  end

end

Thanks. That was a giant waste of most of my afternoon yesterday, so I was glad when I finally got it working!