TestDrivenDevelopmentの研修でのやったソースコードです。

problem.txt

TDD研修の課題です。
課題の内容は: https://gist.github.com/twada/856c37103ebd3d1fb973ba2c2654f9d6

TODO

Product

name | price | sale_date | sale_rate

'MS WORD' | 18800 | [0] | [1]

'Excel' | 27800 | [0, 30] | [2/3, 1/3]

'SQL Server' | 919000 | [0, 60, 120] | [1/3, 1/3, 1/3]

When Init Product
- Word
  - [X] Word Name should be
  - [X] Word Price should be
- Excel
  - [X] Excel Name should be
  - [X] Excel Price should be
- SqlServer
  - [X] SqlServer Name should be
  - [X] SqlServer Price should be

When Sign On Product
- Word
  - [X] Contract Product Name should be Word
  - [X] Contract Product Name should be Today
- Excel
  - [X] Contract Product Name should be Excel
  - [X] Contract Product Name should be Today
- SqlServer
  - [X] Contract Product Name should be SqlServer
  - [X] Contract Product Name should be Today

When Check Sales On Product By Date
- Word
  - [X] Sales on today should be
  - [X] Sales on 30 days after should be
  - [X] Sales on 120 days after should be
  - [X] Sales on date before today should be
- Excel
  - [X] Sales on today should be
  - [X] Sales on 29 days after should be
  - [X] Sales on 30 days after should be
  - [X] Sales on 120 days after should be
  - [X] Sales on date before today should be
- SqlServer
  - [X] Sales on today should be
  - [X] Sales on 59 days after should be
  - [X] Sales on 60 days after should be
  - [X] Sales on 119 days after should be
  - [X] Sales on 120 days after should be
  - [X] Sales on 121 days after should be
  - [X] Sales on date before today should be

product.rb

class Product
  attr_reader :name, :price
  attr_writer :price_code

  # Product.new ('Ms Word', MsWordPrice.new)
  def initialize(name, price_code)
    @name = name
    @price_code = price_code
    @price = @price_code.price
  end

  def revenue_after_num_days(days_after_sale_date)
    @price_code.revenue_after_num_days(days_after_sale_date)
  end
end

module DefaultPrice
  def price_to_int(price)
    price.to_i
  end
end

class MsWordPrice
  include DefaultPrice

  def initialize(price=18800)
    @price = price
  end

  def revenue_after_num_days(days_after_sale_date, price)
    return @price if days_after_sale_date >= 0
    
    return 0
  end
end

class ExcelPrice
  include DefaultPrice

  def initialize(price=27800)
    @price = price
  end

  def revenue_after_num_days(days_after_sale_date)
    return @price if days_after_sale_date >= 30

    return price_to_int(@price * 2/3) if days_after_sale_date >= 0

    return 0
  end
end

class SqlServerPrice
  include DefaultPrice

  def initialize(price=919000)
    @price = price
  end

  def revenue_after_num_days(days_after_sale_date, price)
    return price if days_after_sale_date >= 120

    return price_to_int(@price * 2/3) if days_after_sale_date >= 60

    return price_to_int(@price * 1/3) if days_after_sale_date >= 0

    return 0
  end

end

class Contract
  attr_reader :product, :sign_on
  def initialize(product)
    @product = product
    @sign_on = Time.now.utc.to_date    #
  end

  def sales_on_date(date)
    num_date_after = (date - @sign_on).to_i
    @product.revenue_after_num_days(num_date_after)
  end
end

product_old_version.rb

class Product
  attr_reader :name, :sale_date, :sale_ratio_per_date
  attr_accessor :price

  def revenue_with_rate(rate)
    @price * rate
  end
end


class MsWord < Product
  def initialize(price = 18800)
    @name = 'Word'
    @price = price
    @sale_date = [0]
    @sale_ratio_per_date = [1]
  end
end

class Excel < Product
  def initialize(price = 27800)
    @name = 'Excel'
    @price = price
    @sale_date = [0, 30]
    @sale_ratio_per_date = [2.0/3, 1.0/3]
  end
end

class SqlServer < Product
  def initialize(price = 919000)
    @name = 'SqlServer'
    @price = price
    @sale_date = [0, 60, 120]
    @sale_ratio_per_date = [1.0/3, 1.0/3, 1.0/3]
  end
end

class Contract
  def initialize(product)
    @product = product
    @sign_on = Time.now.utc.to_date    #
  end

  def sign_on
    @sign_on
  end

  def product
    @product
  end

  def sales_on_date(date)
    num_date_after = (date - @sign_on).to_i
    sales_on_date_after(num_date_after)
  end

  def sales_on_date_after(num_date_after)
    total_sales_on_date = 0
    @product.sale_date.each_with_index do |sale_date, idx|
      total_sales_on_date += @product.revenue_with_rate(@product.sale_ratio_per_date[idx]) if (num_date_after  >= sale_date)
    end
    total_sales_on_date.to_i
  end
end

product_spec.rb

describe Product do
  let(:today_date) {Time.now.utc.to_date}

  describe "Product Initization" do
    context "when init Word" do
      let(:word) {MsWord.new}
      it "should Word name" do
        expect(word.name).to eq "Word"
      end
      it "should Word product cost" do
        expect(word.price).to eq (18800)
      end
    end

    context "when init Excel" do
      let(:excel) {Excel.new}
      it "should Excel name" do
        expect(excel.name).to eq "Excel"
      end
      it "should Excel product cost" do
        expect(excel.price).to eq (27800)
      end
    end

    context "when init SqlServer" do
      let(:sql) {SqlServer.new}
      it "should SqlServer name" do
        expect(sql.name).to eq "SqlServer"
      end
      it "should SqlServer product cost" do
        expect(sql.price).to eq (919000)
      end
    end
  end

  describe "sign on" do
    context "when sign on with Word" do
      let(:word) {MsWord.new}
      let(:contract) {Contract.new(word)}
      
      it "should Contract product is word" do
        expect(contract.product.name).to eq "Word"
      end

      it "should Word Contract sign on today" do
        expect(contract.sign_on).to eq today_date
      end
    end

    context "when sign on with Excel" do
      let(:excel) {Excel.new}
      let(:contract) {Contract.new(excel)}
      
      it "should Contract product is excel" do
        expect(contract.product.name).to eq "Excel"
      end

      it "should Excel Contract sign on today" do
        expect(contract.sign_on).to eq today_date
      end
    end

    context "when sign on with SqlServer" do
      let(:sql_server) {SqlServer.new}
      let(:contract) {Contract.new(sql_server)}
      
      it "should Contract product is sqlserver" do
        expect(contract.product.name).to eq "SqlServer"
      end

      it "should SqlServer Contract sign on today" do
        expect(contract.sign_on).to eq today_date
      end
    end
  end

  describe "sales of product on specific date" do
    context "when check revenue with Word" do
      let(:word) {MsWord.new(18800)}
      let(:contract) {Contract.new(word)}
      where(:case_name, :date, :expected_revenue) do 
        [
          ["today", 0, 18800],
          ["after_30_days", 30, 18800],
          ["after_120_days", 120, 18800],
          ["after_before_today", -1, 0]
        ]
      end
      
      with_them do
        it "should revenue of Word" do
          expect(contract.sales_on_date(today_date + date)).to eq expected_revenue
        end
      end
    end

    context "when check revenue with Excel" do
      let(:excel) {Excel.new(27800)}
      let(:contract) {Contract.new(excel)}
      where(:case_name, :date, :expected_revenue) do 
        [
          ["today", 0, 18533],
          ["after_29_days", 29, 18533],
          ["after_30_days", 30, 27800],
          ["after_120_days", 120, 27800]
        ]
      end
      with_them do
        it "should revenue of excel" do
          expect(contract.sales_on_date(today_date + date)).to eq expected_revenue
        end
      end
    end

    context "when check sales with Sql Server" do
      let(:sql) {SqlServer.new(919000)}
      let(:contract) {Contract.new(sql)}
      let(:expeted_sales) {
        {
          'today': (sql.price * 1/3).to_i,
          'after_59_days': (sql.price * 1/3).to_i,
          'after_60_days': (sql.price * 2/3).to_i,
          'after_119_days': (sql.price * 2/3).to_i,
          'after_120_days': sql.price,
          'before_today': 0
        }
      }

      where(:case_name, :date, :expected_revenue) do 
        [
          ["today", 0, 306333],
          ["after_59_days", 59, 306333],
          ["after_60_days", 60, 612666],
          ["after_119_days", 119, 612666],
          ["after_120_days", 120, 919000],
          ["before_today", -1, 0]
        ]
      end

      with_them do
        it "should revenue of Sql Server" do
          expect(contract.sales_on_date(today_date + date)).to eq expected_revenue
        end
      end
    end
  end
end

https://gist.github.com/minhquang4334/ac968f752f23f833f74b30a5a5427d91/revisions#diff-bac85a215cf06c8820f2f2b2c2c8a9b05be7d2003b70489974a1add5f9352cd4R60 で合計値が10,000円にならないので修正必要はありますね。 @minhquang4334