Commit a20e73a

@@ -0,0 +1,60 @@
+require "spec_helper"
+
+class Cart
+  def initialize(items = [])
+    @items = items
+  end
+
+  def add(product)
+    @items.push(product)
+  end
+
+  def includes?(product)
+    @items.include?(product)
+  end
+
+  def quantity_of(product)
+    @items.find_all do |item|
+      item == product
+    end.count
+  end
+end
+
+describe Cart do
+  let(:sut) { Cart.new }
+
+  context "when there are no items in the cart"  do
+    let(:product) { fake }
+    let(:result) { sut.includes?(product) }
+
+    it "should return false" do
+      result.should be_false
+    end
+  end
+
+  context "when adding a product" do
+    let(:product) { fake }
+
+    let(:result) do
+      sut.add(product)
+      sut.quantity_of(product)
+    end
+
+    it "should increase the quanity of that product" do
+      result.should == 1
+    end
+  end
+
+  context "when adding more then one of the same product" do
+    let(:product) { fake }
+
+    let(:result) do
+      sut.add(product)
+      sut.add(product)
+      sut.quantity_of(product)
+    end
+    it "should indicate the total quanity of that product" do
+      result.should == 2
+    end
+  end
+end