Add a few more fields to the Address object.

app/models/address.rb

@@ -1,3 +1,17 @@
+# Value object for addresses.
+
 class Address
-  attr_reader :street, :street2
+  FIELDS = [:street, :street2, :city, :state, :zip]
+  FIELDS.each do |f|
+    attr_reader f
+  end
+
+  # Initializes a new #Address object from a #Hash of fields.
+  def initialize(opts = {})
+    FIELDS.each do |f|
+      if opts.has_key?(f)
+        eval "@#{f.to_s} = opts[:#{f.to_s}]"
+      end
+    end
+  end
 end

spec/models/address_spec.rb

@@ -11,5 +11,35 @@
         @address.should respond_to(m)
       end
     end
+
+    it "should have a city field" do
+      @address.should respond_to(:city)
+    end
+
+    it "should have a state field" do
+      @address.should respond_to(:state)
+    end
+
+    it "should have a zip field" do
+      @address.should respond_to(:zip)
+    end
+  end
+
+  describe '(constructor)' do
+    it "should set all options passed in on legitimate fields" do
+      state = mock_model(State, :code => 'NY', :country => mock_model(Country, :code => 'US'))
+      a = Address.new(:street => '123 Main Street', :street2 => 'Apt. 1', :city => 'Anytown', :state => state, :zip => '12345')
+      a.street.should == '123 Main Street'
+      a.street2.should == 'Apt. 1'
+      a.city.should == 'Anytown'
+      a.state.should == state
+      a.zip.should == '12345'
+    end
+
+    it "should ignore bogus fields in the constructor" do
+      lambda { @a = Address.new(:street => 'real field', :bogus => 'bogus field') }.should_not raise_error
+      @a.street.should == 'real field'
+      @a.should_not respond_to(:bogus)
+    end
   end
 end