Add catalogue and product classes. Refactor following code review.

Author: John Ollier

.DS_Store

@@ -0,0 +1,3 @@
+.idea
+.rspec
+.DS_Store

.gitignore

@@ -1,40 +1,47 @@
 class Basket
-  attr_accessor :basket
-  def initialize
-    @basket = { "FR1" => 0,
-                "SR1" => 0,
-                "CF1" => 0,
-    }
-  end
+  attr_reader :purchases
 
-  def show_basket
-    return "#{@basket} costs: £#{basket_total}"
+  def initialize(catalogue)
+    # the class is called basket, lets think of a different descriptive name
+    @purchases = Hash.new
+    @catalogue = catalogue
+    @catalogue.products_by_code.each_key { |p_code| @purchases[p_code] = 0 }
   end
 
-  def basket_total
-    ((@basket["FR1"] * 311) + (@basket["SR1"] * 500) + (@basket["CF1"] * 1123)) / 100.00
+  def show_basket
+    # #{@basket} will call to_s method of Basket
   end
 
-  def add(x)
-    @basket[x] = @basket[x] + 1
+  def total
+    running_total = 0
+    @purchases.each do |code, quantity|
+      running_total = running_total + quantity * @catalogue.products_by_code[code].price
+    end
+    return running_total
   end
 
-  def remove(x)
-    @basket[x] = @basket[x] - 1 if @basket[x] > 0
+  # give our parameter a descriptive name
+  def add(product_code)
+    # what if the user passes a non existant product code
+    if @purchases.key?(product_code)
+      @purchases[product_code] = @purchases[product_code] + 1
+    else
+      # TODO can do better than this
+      print("Error: no product with code: #{product_code}")
+    end
   end
 
-  def complete_purchase
-    running_price = basket_total
-    @basket = { "FR1" => 0,
-                "SR1" => 0,
-                "CF1" => 0,
-    }
-    return "That cost £#{running_price} and your basket is now empty"
-
+  def remove(product_code)
+    if @purchases.key?(product_code)
+      if purchases[product_code] > 0
+        purchases[product_code] = purchases[product_code] - 1
+      else
+        print("Warning: no product with code #{product_code} in basket")
+      end
+    else
+      # TODO can do better than this
+      print("Error: no product with code: #{product_code}")
+    end
   end
 
 end
-
-def start_checkout
-  Basket.new
-end

Lib/basket.rb

@@ -0,0 +1,14 @@
+require 'product'
+
+class Catalogue
+
+  attr_reader :products_by_code
+
+  def initialize()
+    fruit_tea = Product.new('FR1','Fruit Tea', 311)
+    strawberries = Product.new('SR1','Strawberries', 500)
+    coffee = Product.new('CF1','Coffee', 1123)
+    @products_by_code = {'FR1' => fruit_tea, 'SR1' => strawberries, 'CF1' => coffee}
+  end
+
+end

Lib/catalogue.rb

@@ -0,0 +1,12 @@
+puts "Welcome to the GDS supermarket"
+
+finish = false
+
+while !finish
+  puts "Please enter command"
+  command = gets
+  if command == 'checkout':
+    finish = true
+  end
+
+end

Lib/item.rb

@@ -0,0 +1,15 @@
+class Product
+
+  attr_reader :code, :name, :price
+
+  def initialize(code, name, price)
+    @code = code
+    @name = name
+    @price = price
+  end
+
+  def to_s
+    "Product: code: #{code}, name: #{name}, price: #{price}"
+  end
+
+end

Lib/main.rb

@@ -0,0 +1,63 @@
+require 'basket'
+require 'catalogue'
+
+describe Basket do
+  catalogue = Catalogue.new
+  describe '#initialize' do
+    it "is empty initially" do
+      basket = Basket.new(catalogue)
+      # when testing methods test the data not a formatted message containing the data
+      expect(basket.purchases['FR1']).to eq(0)
+      expect(basket.purchases['SR1']).to eq(0)
+      expect(basket.purchases['CF1']).to eq(0)
+    end
+  end
+  describe '#add' do
+    it "can add a valid item" do
+      basket = Basket.new(catalogue)
+      basket.add("FR1")
+      expect(basket.purchases['FR1']).to eq(1)
+      expect(basket.purchases['SR1']).to eq(0)
+      expect(basket.purchases['CF1']).to eq(0)
+    end
+    it "will not add an invalid item" do
+      basket = Basket.new(catalogue)
+      basket.add("ZZZ")
+      expect(basket.purchases['FR1']).to eq(0)
+      expect(basket.purchases['SR1']).to eq(0)
+      expect(basket.purchases['CF1']).to eq(0)
+    end
+  end
+  describe '#remove' do
+    it "can remove a valid item if present" do
+      basket = Basket.new(catalogue)
+      basket.add("FR1")
+      basket.add("FR1")
+      basket.remove("FR1")
+      expect(basket.purchases['FR1']).to eq(1)
+      expect(basket.purchases['SR1']).to eq(0)
+      expect(basket.purchases['CF1']).to eq(0)
+    end
+    it "will not remove an invalid item" do
+      basket = Basket.new(catalogue)
+      basket.remove("ZZZ")
+      expect(basket.purchases['FR1']).to eq(0)
+      expect(basket.purchases['SR1']).to eq(0)
+      expect(basket.purchases['CF1']).to eq(0)
+    end
+  end
+  describe '#total' do
+    it "will be zero initially" do
+      basket = Basket.new(catalogue)
+      expect(basket.total).to eq(0)
+    end
+    it "will calculate the running total" do
+      basket = Basket.new(catalogue)
+      basket.add("FR1")
+      basket.add("FR1")
+      basket.add("CF1")
+      expect(basket.total).to eq(1745)
+    end
+  end
+end
+

Lib/product.rb

@@ -0,0 +1,11 @@
+require 'catalogue'
+
+describe Catalogue do
+  describe '#initialize' do
+    it "has all products" do
+      catalogue = Catalogue.new
+      # when testing methods test the data not a formatted message containing the data
+      expect(catalogue.products_by_code['FR1'].code).to eq('FR1')
+    end
+  end
+end

Spec/basket_spec.rb

@@ -0,0 +1,16 @@
+require 'product'
+
+describe Product do
+  it "has a code" do
+    fruit_tea = Product.new('FR1','Fruit Tea', 311)
+    expect(fruit_tea.code).to eq('FR1')
+  end
+  it "has a name" do
+    fruit_tea = Product.new('FR1','Fruit Tea', 311)
+    expect(fruit_tea.name).to eq('Fruit Tea')
+  end
+  it "has a price" do
+    fruit_tea = Product.new('FR1','Fruit Tea', 311)
+    expect(fruit_tea.price).to eq(311)
+  end
+end

Spec/catalogue_spec.rb

@@ -0,0 +1,103 @@
+# This file was generated by the `rspec --init` command. Conventionally, all
+# specs live under a `spec` directory, which RSpec adds to the `$LOAD_PATH`.
+# The generated `.rspec` file contains `--require spec_helper` which will cause
+# this file to always be loaded, without a need to explicitly require it in any
+# files.
+#
+# Given that it is always loaded, you are encouraged to keep this file as
+# light-weight as possible. Requiring heavyweight dependencies from this file
+# will add to the boot time of your test suite on EVERY test run, even for an
+# individual file that may not need all of that loaded. Instead, consider making
+# a separate helper file that requires the additional dependencies and performs
+# the additional setup, and require it from the spec files that actually need
+# it.
+#
+# The `.rspec` file also contains a few flags that are not defaults but that
+# users commonly want.
+#
+# See http://rubydoc.info/gems/rspec-core/RSpec/Core/Configuration
+RSpec.configure do |config|
+  # rspec-expectations config goes here. You can use an alternate
+  # assertion/expectation library such as wrong or the stdlib/minitest
+  # assertions if you prefer.
+  config.expect_with :rspec do |expectations|
+    # This option will default to `true` in RSpec 4. It makes the `description`
+    # and `failure_message` of custom matchers include text for helper methods
+    # defined using `chain`, e.g.:
+    #     be_bigger_than(2).and_smaller_than(4).description
+    #     # => "be bigger than 2 and smaller than 4"
+    # ...rather than:
+    #     # => "be bigger than 2"
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  # rspec-mocks config goes here. You can use an alternate test double
+  # library (such as bogus or mocha) by changing the `mock_with` option here.
+  config.mock_with :rspec do |mocks|
+    # Prevents you from mocking or stubbing a method that does not exist on
+    # a real object. This is generally recommended, and will default to
+    # `true` in RSpec 4.
+    mocks.verify_partial_doubles = true
+  end
+
+  # This option will default to `:apply_to_host_groups` in RSpec 4 (and will
+  # have no way to turn it off -- the option exists only for backwards
+  # compatibility in RSpec 3). It causes shared context metadata to be
+  # inherited by the metadata hash of host groups and examples, rather than
+  # triggering implicit auto-inclusion in groups with matching metadata.
+  config.shared_context_metadata_behavior = :apply_to_host_groups
+
+# The settings below are suggested to provide a good initial experience
+# with RSpec, but feel free to customize to your heart's content.
+=begin
+  # This allows you to limit a spec run to individual examples or groups
+  # you care about by tagging them with `:focus` metadata. When nothing
+  # is tagged with `:focus`, all examples get run. RSpec also provides
+  # aliases for `it`, `describe`, and `context` that include `:focus`
+  # metadata: `fit`, `fdescribe` and `fcontext`, respectively.
+  config.filter_run_when_matching :focus
+
+  # Allows RSpec to persist some state between runs in order to support
+  # the `--only-failures` and `--next-failure` CLI options. We recommend
+  # you configure your source control system to ignore this file.
+  config.example_status_persistence_file_path = "spec/examples.txt"
+
+  # Limits the available syntax to the non-monkey patched syntax that is
+  # recommended. For more details, see:
+  #   - http://rspec.info/blog/2012/06/rspecs-new-expectation-syntax/
+  #   - http://www.teaisaweso.me/blog/2013/05/27/rspecs-new-message-expectation-syntax/
+  #   - http://rspec.info/blog/2014/05/notable-changes-in-rspec-3/#zero-monkey-patching-mode
+  config.disable_monkey_patching!
+
+  # This setting enables warnings. It's recommended, but in some cases may
+  # be too noisy due to issues in dependencies.
+  config.warnings = true
+
+  # Many RSpec users commonly either run the entire suite or an individual
+  # file, and it's useful to allow more verbose output when running an
+  # individual spec file.
+  if config.files_to_run.one?
+    # Use the documentation formatter for detailed output,
+    # unless a formatter has already been configured
+    # (e.g. via a command-line flag).
+    config.default_formatter = 'doc'
+  end
+
+  # Print the 10 slowest examples and example groups at the
+  # end of the spec run, to help surface which specs are running
+  # particularly slow.
+  config.profile_examples = 10
+
+  # Run specs in random order to surface order dependencies. If you find an
+  # order dependency and want to debug it, you can fix the order by providing
+  # the seed, which is printed after each run.
+  #     --seed 1234
+  config.order = :random
+
+  # Seed global randomization in this process using the `--seed` CLI option.
+  # Setting this allows you to use `--seed` to deterministically reproduce
+  # test failures related to randomization by passing the same `--seed` value
+  # as the one that triggered the failure.
+  Kernel.srand config.seed
+=end
+end