pet name test demo

pet.rb

class Pet
  attr_accessor :name

  def initialize(name)
    @name = name
  end

  def rename(new_name)
    @name = new_name
  end

  # .. more methods
end

test_before.rb

require 'minitest/autorun'
require 'minitest/reporters'
require_relative 'pet'

describe "Pet" do
  before do
    puts "Creating a pet named Fido"
    @pet = Pet.new("Fido")
  end
  
  it "must have a name" do
    expect(@pet.name).must_equal "Fido"
  end

  it "must rename pet" do
    expect(@pet.name).must_equal "Fido"

    @pet.rename( "Fitzgerald" )
    expect(@pet.name).must_equal "Fitzgerald"
  end

  it "Throws an ArgumentError if created without a name" do
    expect {
      Pet.new()
    }.must_raise ArgumentError
  end
end

test_let.rb

require 'minitest/autorun'
require 'minitest/reporters'
require_relative 'pet'

describe "Pet" do
  let (:pet) {
    puts "Creating a pet named Fitzgerald"
    Pet.new("Fitzgerald")
  }

  it "must have a name" do
    expect(pet.name).must_equal "Fitzgerald"
  end

  it "must rename the pet" do
    expect(pet.name).must_equal "Fitzgerald"

    pet.rename( "Fido" )
    expect(pet.name).must_equal "Fido"
  end

  it "Throws an ArgumentError if created without a name" do
    expect {
      Pet.new
    }.must_raise ArgumentError
  end
end