Replace Subclasses with Strategies: Step Four

* Move subclass-specific behavior into strategies

example_app/app/models/multiple_choice_question.rb

@@ -4,11 +4,7 @@ class MultipleChoiceQuestion < Question
   accepts_nested_attributes_for :options, reject_if: :all_blank
 
   def options_for_form
-    if options.any?
-      options
-    else
-      [Option.new, Option.new, Option.new]
-    end
+    submittable.options_for_form
   end
 
   def submittable

example_app/app/models/multiple_choice_submittable.rb

@@ -13,6 +13,14 @@ def breakdown
     percents.join(', ')
   end
 
+  def options_for_form
+    if options.any?
+      options
+    else
+      [Option.new, Option.new, Option.new]
+    end
+  end
+
   def score(text)
     options.score(text)
   end

example_app/app/models/scale_question.rb

@@ -3,7 +3,7 @@ class ScaleQuestion < Question
   validates :minimum, presence: true
 
   def steps
-    (minimum..maximum).to_a
+    submittable.steps
   end
 
   def submittable

example_app/app/models/scale_submittable.rb

@@ -11,6 +11,10 @@ def score(text)
     text.to_i
   end
 
+  def steps
+    (@question.minimum..@question.maximum).to_a
+  end
+
   private
 
   def answers

example_app/spec/models/multiple_choice_question_spec.rb

@@ -1,16 +1,3 @@
 describe MultipleChoiceQuestion do
   it { should have_many(:options) }
 end
-
-describe MultipleChoiceQuestion, '#options_for_form' do
-  it 'adds empty options when none are present' do
-    question = build_stubbed(:multiple_choice_question, options: [])
-    question.options_for_form.count.should == 3
-  end
-
-  it 'leaves existing options alone' do
-    options = [Option.new(text: 'hey'), Option.new(text: 'hello')]
-    question = build_stubbed(:multiple_choice_question, options: options)
-    question.options_for_form.map(&:text).should match_array(['hey', 'hello'])
-  end
-end

example_app/spec/models/multiple_choice_submittable_spec.rb

@@ -16,6 +16,21 @@
   end
 end
 
+describe MultipleChoiceSubmittable, '#options_for_form' do
+  it 'adds empty options when none are present' do
+    question = build_stubbed(:multiple_choice_question, options: [])
+    submittable = MultipleChoiceSubmittable.new(question)
+    submittable.options_for_form.count.should == 3
+  end
+
+  it 'leaves existing options alone' do
+    options = [Option.new(text: 'hey'), Option.new(text: 'hello')]
+    question = build_stubbed(:multiple_choice_question, options: options)
+    submittable = MultipleChoiceSubmittable.new(question)
+    submittable.options_for_form.map(&:text).should match_array(['hey', 'hello'])
+  end
+end
+
 describe MultipleChoiceSubmittable, '#score' do
   it 'returns the score for the option with the given text' do
     question = build_stubbed(:multiple_choice_question)

example_app/spec/models/scale_question_spec.rb

@@ -4,10 +4,3 @@
   it { should validate_presence_of(:maximum) }
   it { should validate_presence_of(:minimum) }
 end
-
-describe ScaleQuestion, '#steps' do
-  it 'returns all numbers starting at the minimum and ending at the maximum' do
-    question = build_stubbed(:scale_question, minimum: 2, maximum: 5)
-    question.steps.should eq [2, 3, 4, 5]
-  end
-end

example_app/spec/models/scale_submittable_spec.rb

@@ -22,3 +22,11 @@
     result.should eq 5
   end
 end
+
+describe ScaleSubmittable, '#steps' do
+  it 'returns all numbers starting at the minimum and ending at the maximum' do
+    question = build_stubbed(:scale_question, minimum: 2, maximum: 5)
+    submittable = ScaleSubmittable.new(question)
+    submittable.steps.should eq [2, 3, 4, 5]
+  end
+end