Fixing CastedModel bug that modified casted objects

Also refactored code for skipping casting of nil-valued properties
Added and re-arranged specs

lib/couchrest/mixins/properties.rb

@@ -39,9 +39,10 @@ module CouchRest
         self.class.properties.each do |property|
           next unless property.casted
           key = self.has_key?(property.name) ? property.name : property.name.to_sym
+          # Don't cast the property unless it has a value
+          next unless self[key]
           target = property.type
           if target.is_a?(Array)
-            next unless self[key]
             klass = ::CouchRest.constantize(target[0])
             self[property.name] = self[key].collect do |value|
               # Auto parse Time objects
@@ -56,8 +57,7 @@ module CouchRest
             else
               # Let people use :send as a Time parse arg
               klass = ::CouchRest.constantize(target)
-              # Only cast this key if it has a value. Otherwise, leave nil.
-              self[key].nil? ? nil : klass.send(property.init_method, self[key])
+              klass.send(property.init_method, self[key].dup)
             end
             self[property.name].casted_by = self if self[property.name].respond_to?(:casted_by)
           end

spec/couchrest/more/casted_extended_doc_spec.rb

@@ -18,23 +18,58 @@ end
 
 describe "casting an extended document" do
   
+  before(:each) do
+    @driver = Driver.new(:name => 'Matt')
+    @car    = Car.new(:name => 'Renault 306', :driver => @driver)
+  end
+
+  it "should retain all properties of the casted attribute" do
+    @car.driver.should == @driver
+  end
+  
+  it "should let the casted document know who casted it" do
+    @car.driver.casted_by.should == @car
+  end
+end
+
+describe "assigning a value to casted attribute after initializing an object" do
+
   before(:each) do
     @car    = Car.new(:name => 'Renault 306')
     @driver = Driver.new(:name => 'Matt')
   end
   
-  # it "should not create an empty casted object" do
-  #   @car.driver.should be_nil
-  # end
+  it "should not create an empty casted object" do
+    @car.driver.should be_nil
+  end
   
-  it "should let you assign the casted attribute after instantializing an object" do
+  # Note that this isn't casting the attribute, it's just assigning it a value
+  # (see "should not cast attribute")
+  it "should let you assign the value" do
     @car.driver = @driver
     @car.driver.name.should == 'Matt'
   end
   
-  it "should let the casted document who casted it" do
-    Car.new(:name => 'Renault 306', :driver => @driver)
-    @car.driver.casted_by.should == @car
+  it "should not cast attribute" do
+    @car.driver = JSON.parse(JSON.generate(@driver))
+    @car.driver.should_not be_instance_of(Driver)
+  end
+
+end
+
+describe "casting an extended document from parsed JSON" do
+
+  before(:each) do
+    @driver = Driver.new(:name => 'Matt')
+    @car    = Car.new(:name => 'Renault 306', :driver => @driver)
+    @new_car = Car.new(JSON.parse(JSON.generate(@car)))
+  end
+
+  it "should cast casted attribute" do
+    @new_car.driver.should be_instance_of(Driver)
   end
   
+  it "should retain all properties of the casted attribute" do
+    @new_car.driver.should == @driver
+  end
 end