person.rb

class Person

  attr_accessor :name, :age

  def initialize(args)
    @name = args[:name]
    @age = args[:age]
  end

  def scream_greeting
    greeting = get_greeting
    return greeting
  end

  def get_greeting
    return "hello world"
  end

end

person_Spec.rb

# require 'spec_helper' # this is not necessary since we add this to .rspec
require_relative "../lib/Person.rb"

# ##### Execution #####
# run with 'rspec --format doc --color Person_spec.rb'
# or run with 'rspec --format html --color Person_spec.rb > results.html
#  followed by open results.html'

# ##### General #####
# describe is a method, it is a way to group examples
# it is a method, it describes a property
# store flags you'd pass into to rspec command in .rspec
# add configuration to spec_helper. rb

# ##### Tips #####
# Test for expected behavior NOT implementation

RSpec.describe 'a person' do

  it 'has a name' do
    raise unless Person.new({:name => 'ellis'}).name == 'ellis'
  end

  it 'has an age' do
    raise unless Person.new({:age => 26}).age = 26
  end

  describe '#scream_greeting' do
    it 'should return hello world' do
      person = double()
      person.stub(:get_greeting) 
      expect(Person.new({}).scream_greeting).to eq("hello world")
    end
  end

end