Feature/add property (#6)

* Add TDD form for property

* Add working code to add a property to the model

* Add model spec and lib for property

lib/testing_record/model.rb

@@ -20,12 +20,34 @@ def caching(option)
         define_singleton_method(cache_name) { instance_variable_get(ivar_name) }
       end
 
+      # Creates an instance of the model, adding it to the cache if caching is enabled
+      #
+      # @return [TestingRecord::Model]
       def create(attributes = {})
         new(attributes).tap do |entity|
           add_to_cache(entity) if respond_to?(cache_name)
         end
       end
 
+      # Sets a property on the model, this should have a name and an optional type (Defaults to `:singular`)
+      #
+      # @return [Array<Hash>]
+      def property(name, type: :singular)
+        raise Error, 'Invalid type option, must be :singular or :plural' unless type_valid?(type)
+
+        if type == :plural
+          attr_reader :"#{name}s"
+        else
+          attr_reader name
+        end
+
+        properties << { name:, type: }
+      end
+
+      def properties
+        @properties ||= []
+      end
+
       # Set the type of model, this should be one of `:singular` or `:plural`
       #
       # @return [Symbol]

spec/testing_record/model_spec.rb

@@ -60,11 +60,11 @@
       end
 
       it 'generates a new instance of the model entity' do
-        expect(Foo.create({})).to be_a Foo
+        expect(Foo.create).to be_a Foo
       end
 
       it 'will add the entity to the cache' do
-        expect { Foo.create({}) }.to change(Foo.foos, :length).by(1)
+        expect { Foo.create }.to change(Foo.foos, :length).by(1)
       end
     end
 
@@ -75,7 +75,7 @@
       end
 
       it 'generates a new instance of the model entity' do
-        expect(Foo.create({})).to be_a Foo
+        expect(Foo.create).to be_a Foo
       end
 
       it 'does not generate a cache add the entity to the cache' do
@@ -93,4 +93,64 @@
       end
     end
   end
+
+  describe '.property' do
+    context 'when not classified' do
+      let(:model) do
+        Class.new(TestingRecord::Model) do
+          property :bar
+        end
+      end
+
+      it 'sets the property as a method on the model instance' do
+        expect(model.create).to respond_to(:bar)
+      end
+
+      it 'stores the property as a singular type on the model' do
+        expect(model.properties).to include({ name: :bar, type: :singular })
+      end
+    end
+
+    context 'when classified as singular' do
+      let(:model) do
+        Class.new(TestingRecord::Model) do
+          property :bar, type: :singular
+        end
+      end
+
+      it 'sets the property as a method on the model instance' do
+        expect(model.create).to respond_to(:bar)
+      end
+
+      it 'stores the property as a singular type on the model' do
+        expect(model.properties).to include({ name: :bar, type: :singular })
+      end
+    end
+
+    context 'when classified as plural' do
+      let(:model) do
+        Class.new(TestingRecord::Model) do
+          property :bar, type: :plural
+        end
+      end
+
+      it 'sets the property as a method on the model instance' do
+        expect(model.create).to respond_to(:bars)
+      end
+
+      it 'stores the property as a singular type on the model' do
+        expect(model.properties).to include({ name: :bar, type: :plural })
+      end
+    end
+
+    context 'with an invalid type setting' do
+      before do
+        stub_const('Foo', Class.new(described_class))
+      end
+
+      it 'cannot be configured on the model' do
+        expect { Foo.property :bar, type: :invalid }.to raise_error(TestingRecord::Error)
+      end
+    end
+  end
 end