tap/spec/models/product_spec.rb

# == Schema Information
#
# Table name: products
#
#  id                  :integer          not null, primary key
#  name                :string           not null
#  price_cents         :integer          default("0"), not null
#  created_at          :datetime
#  updated_at          :datetime
#  avatar_file_name    :string
#  avatar_content_type :string
#  avatar_file_size    :integer
#  avatar_updated_at   :datetime
#  category            :integer          default("0")
#  stock               :integer          default("0"), not null
#  calories            :integer
#  deleted             :boolean          default("f")
#

describe Product do
  before :each do
    @product = create :product
  end

  it 'has a valid factory' do
    expect(@product).to be_valid
  end

  ############
  #  FIELDS  #
  ############

  describe 'fields' do
    describe 'name' do
      it 'should be present' do
        @product.name = nil
        expect(@product).to_not be_valid
      end

      it 'shold be unique' do
        expect(build :product, name: @product.name).to_not be_valid
      end
    end

    describe 'price_cents' do
      it 'should be present' do
        @product.price_cents = nil
        expect(@product).to_not be_valid
      end

      it 'should be a number' do
        @product.price_cents = "123abc"
        expect(@product).to_not be_valid
      end

      it 'should be strict positive' do
        @product.price = -5
        expect(@product).to_not be_valid
        @product.price = 0
        expect(@product).to_not be_valid
      end
    end

    describe 'stock' do
      it 'should be present' do
        @product.stock = nil
        expect(@product).to_not be_valid
      end

      it 'should be positive' do
        @product.stock = -5
        expect(@product).to_not be_valid
        @product.stock = 0
        expect(@product).to be_valid
      end
    end

    describe 'calories' do
      it 'does not have to be present' do
        @product.calories = nil
        expect(@product).to be_valid
      end

      it 'should be positive' do
        @product.calories = -5
        expect(@product).to_not be_valid
      end
    end

    describe 'avatar' do
      it 'should be present' do
        @product.avatar = nil
        expect(@product).to_not be_valid
      end
    end
  end

  #############
  #  METHODS  #
  #############

  describe 'price' do
    it 'should read the correct value' do
      expect(@product.price).to eq(@product.price_cents / 100.0)
    end

    it 'should write the correct value' do
      @product.price = 1.5
      @product.save
      expect(@product.reload.price_cents).to eq(150)
    end
  end

end