title: received :update_attributes with unexpected arguments
body: <p>I am very new to rspec and factory girl and I am stuck with a strange problem. I have an action in a controller like:</p>
  
  <pre><code>   def update
        @property = current_user.properties.find params[:fee][:property_id]
        @fee = @property.fees.find(params[:id])
       if @fee.update_attributes(params[:fee])
         redirect_to fee_path(:prop=&gt;@property), :notice =&gt; "fee updated successfully!"
       else
         render action: "edit"
       end
     end
  </code></pre>
  
  <p>and a test example:</p>
  
  <pre><code>    describe "with valid params" do
        before do
          @property = FactoryGirl.create(:property)
          @property.users &lt;&lt; subject.current_user
        end
        it "updates the requested fee" do
          fee = @property.fees.create! valid_attributes
          Fee.any_instance.should_receive(:update_attributes).with({ "name" =&gt; "MyString","property_id"=&gt;@property.id})
          put :update, {:id =&gt; fee.to_param, :fee =&gt; { "name" =&gt; "MyString","property_id"=&gt;@property.id }}, valid_session
        end
      end
  </code></pre>
  
  <p>but I get a strange error:</p>
  
  <pre><code>    #&lt;Fee:0xb8c4884&gt; received :update_attributes with unexpected arguments
       expected: ({"name"=&gt;"MyString", "property_id"=&gt;"50ec0b3fa7c320ee53000002"})
            got: ({"name"=&gt;"MyString", "property_id"=&gt;"50ec0b3fa7c320ee53000002"})
  </code></pre>
  
  <p>If anyone can help I'll be very thankful.</p>