In this exercise, we will take a step back from testing and create a mini program with multiple classes that inherit from each other

classical_inheritance.rb

#init
module Flight
  attr_accessor :airspeed_velocity

  def fly
    "I'm a #{self.class.name}, I'm flying!"
  end
end

# =============================

class Animal
  def exist?
    true
  end
end

# ==============================

class Mammal < Animal
  attr_reader :blood_temp, :num_legs, :num_arms

  def initialize
    @blood_temp = "warm"
    @num_legs = 2
    @num_arms = 2
  end
end

class Primate < Mammal
  attr_reader :hairy

  def initialize
    @hairy = "yes"
    super
  end
end

class Chimpanzee < Primate
  def uses_tools?
    true
  end
end

class Bat < Mammal
  include Flight

  attr_accessor :wings

  def initialize
    @wings = "Leathery"
  end

end


# ======================

class Amphibian < Animal
  attr_reader :blood_temp

  def initialize
    @blood_temp = "cold"
  end
end

class Frog < Amphibian
  attr_reader :hops

  def initialize
    @hops = true
    super
  end
end

# ======================
class Bird < Animal
  attr_reader :beak

  def initialize
    @beak = "yes"
  end
end

class Parrot < Bird
  include Flight

  def colourful?
    true
  end

end

# koko = Chimpanzee.new
# puts koko.inspect
# puts "Exists? #{koko.exist?}"
#
#
# frogger = Frog.new
# puts frogger.inspect
# puts "Blood temp: #{frogger.blood_temp}"
# puts "Hops: #{frogger.hops}"
#
# polly = Parrot.new
# puts polly.inspect
# puts "Colourful: #{polly.colourful?}"
# puts polly.fly
#
# puts Bat.new.fly

rspec_tests.rb

#rspec
require "./classical_inheritance"

# describe Animal do
#   it "can create Animals" do
#     expect(Animal.new).to be_a Animal
#   end
# end

describe Chimpanzee do
  it "creates Chimpanzees" do
    expect(Chimpanzee.new).to be_a Chimpanzee
  end
  describe "#exist?" do
    it "returns true if Chimpanzee inherits from Animal" do
      koko = Chimpanzee.new
      exists = koko.exist?
      expect(exists).to be true
    end
  end
end

describe Frog do
  it "creates Frogs" do
    frogger = Frog.new
    expect(frogger).to be_a Frog
  end
  it "has a blood temp of cold" do
    frogger = Frog.new
    result = frogger.blood_temp
    expect(result).to eq("cold")
  end
end

describe Parrot do
  it "creates Parrots" do
    polly = Parrot.new
    expect(polly).to be_a Parrot
  end
  it "flies if it inherits fly from Flight" do
    polly = Parrot.new
    result = polly.fly
    expect(result).to eq("I'm a Parrot, I'm flying!")
  end
end

describe Bat do
  it "flies if it inherits fly from Flight" do
    stella = Bat.new
    result = stella.fly
    expect(result).to eq("I'm a Bat, I'm flying!")
  end
end
# puts Bat.new.fly