rspec users - Dec 2008 - problem to mock association proxy

Hello, I''m trying learn Rspec but having problems to understand when
and how
user mocks and stubs.
I have a properties_controller with to before_filter actions
(check_administrator_role e load_user)... to access index action of
properties_controller I need have a params[:user] and this parameter will be
used to load ther user in method load_user ...

Like bellow:

  before_filter :check_administrator_role
  before_filter :load_user

  # GET /properties
  def index
    @properties = @user.properties
  end

  private
  def load_user
    @user = User.find(params[:user_id])
    if @user.nil?
      flash[:notice] = "Registro não encontrado"
      redirect_to root_path
    end
  end

But I don''t know how test index and load_user without fixtures, take a
look
on my specs:

describe PropertiesController do

  def mock_property(stubs={})
    @mock_property ||= mock_model(Property, stubs)
  end

  before do
    @current_user = mock_model(User, :id => 1)
    controller.stub!(:check_administrator_role).and_return(true)
    @user = mock_model(User, :id=>1)
    controller.stub!(:load_user).and_return(@user)
  end

  describe "responding to GET index" do

    it "should expose all properties of given user as @properties" do
      @user.should_receive(:properties).and_return([mock_property])
      get :index
      assigns[:properties].should == [mock_property]
    end

  end


But I having this error:

NoMethodError in ''PropertiesController responding to GET index should
expose
all properties of given user as @properties''
You have a nil object when you didn''t expect it!
The error occurred while evaluating nil.properties
/Users/daniellopes/Trabalhos/luvima/luvima/app/controllers/properties_controller.rb:8:in
`index''
./spec/controllers/properties_controller_spec.rb:21:

So, how is the right way to mock associated records?

Thanks.


Atenciosamente,

Daniel Lopes  ?  Area Cria??es
Design, Websites e Sistemas Web

Visite:  http://www.areacriacoes.com.br/projects
          http://blog.areacriacoes.com.br/

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*
55 (31) 3077-4560  /  55 (31) 8808-8748  /  55 (31) 8737-7501
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On 5 Dec 2008, at 13:42, Daniel Lopes wrote:
> NoMethodError in ''PropertiesController responding to GET index  
> should expose all properties of given user as @properties''
> You have a nil object when you didn''t expect it!
> The error occurred while evaluating nil.properties
> /Users/daniellopes/Trabalhos/luvima/luvima/app/controllers/ 
> properties_controller.rb:8:in `index''
> ./spec/controllers/properties_controller_spec.rb:21:
>
> So, how is the right way to mock associated records?
Hi Daniel

The error you are seeing is because the assignment to @user happens  
inside #load_user: the live code never call` `@user = load_user`.  As  
far as possible, you want to avoid modifying objects under test -  
private methods are only the business of instances of that class.   
It''s much safer in this case to do

   User.should_receive(:find).and_return(@user)

That way, the filter will run as normal.

As for the association - it''s actually irrelevant what that returns.   
All you care is that whatever comes out of `@user.properties` is  
assingned to the view.  I tend to use symbols to represent objects  
(including arrays) that get passed around.  For example:

describe PropertiesController do

   # Not needed
   # def mock_property(stubs={})
   #  @mock_property ||= mock_model(Property, stubs)
   # end

   before do
     controller.stub!(:check_administrator_role).and_return(true)
     @user = mock_model(User, :id=>1, :properties => :user_properties)
     User.stub!(:find).and_return(@user)
   end

   describe "responding to GET index" do
     it "should expose all properties of given user as @properties" do
       get :index
       assigns[:properties].should == :user_properties
     end
   end

end

HTH

Ashley

-- 
http://www.patchspace.co.uk/
http://aviewfromafar.net/

Thanks Ashley, now the tests passed... but I want understand one thing:
This line is only saying that @properties (assigned[:properties]) have some
value ... is that?
assigns[:properties].should == :user_properties

I can change above to assigns[:properties].should_not be_nill and the
semantic value will be the same, right?

Thanks...

Atenciosamente,

Daniel Lopes  ?  Area Cria??es
Design, Websites e Sistemas Web

Visite:  http://www.areacriacoes.com.br/projects
          http://blog.areacriacoes.com.br/

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
55 (31) 3077-4560  /  55 (31) 8808-8748  /  55 (31) 8737-7501


On Fri, Dec 5, 2008 at 6:16 PM, Ashley Moran
<ashley.moran at patchspace.co.uk>wrote:
>
> On 5 Dec 2008, at 13:42, Daniel Lopes wrote:
>
>  NoMethodError in ''PropertiesController responding to GET index
should
>> expose all properties of given user as @properties''
>> You have a nil object when you didn''t expect it!
>> The error occurred while evaluating nil.properties
>>
/Users/daniellopes/Trabalhos/luvima/luvima/app/controllers/properties_controller.rb:8:in
>> `index''
>> ./spec/controllers/properties_controller_spec.rb:21:
>>
>> So, how is the right way to mock associated records?
>>
>
> Hi Daniel
>
> The error you are seeing is because the assignment to @user happens inside
> #load_user: the live code never call` `@user = load_user`.  As far as
> possible, you want to avoid modifying objects under test - private methods
> are only the business of instances of that class.  It''s much safer
in this
> case to do
>
>  User.should_receive(:find).and_return(@user)
>
> That way, the filter will run as normal.
>
> As for the association - it''s actually irrelevant what that
returns.  All
> you care is that whatever comes out of `@user.properties` is assingned to
> the view.  I tend to use symbols to represent objects (including arrays)
> that get passed around.  For example:
>
> describe PropertiesController do
>
>  # Not needed
>  # def mock_property(stubs={})
>  #  @mock_property ||= mock_model(Property, stubs)
>  # end
>
>  before do
>    controller.stub!(:check_administrator_role).and_return(true)
>    @user = mock_model(User, :id=>1, :properties => :user_properties)
>    User.stub!(:find).and_return(@user)
>  end
>
>  describe "responding to GET index" do
>    it "should expose all properties of given user as @properties"
do
>      get :index
>      assigns[:properties].should == :user_properties
>    end
>  end
>
> end
>
> HTH
>
> Ashley
>
> --
> http://www.patchspace.co.uk/
> http://aviewfromafar.net/
>
>
>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
>
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On 5 Dec 2008, at 20:26, Daniel Area Cria??es wrote:
> This line is only saying that @properties (assigned[:properties])  
> have some value ... is that?
> assigns[:properties].should == :user_properties
>
> I can change above to assigns[:properties].should_not be_nill and  
> the semantic value will be the same, right?

Ah no, the semantic value is different because this would also pass:

   def index
     @properties = "vegetable soup"
   end

Yet that does not implement the same behaviour.

When you write a behaviour example, always ask the question "What  
could I realistically write that could pass this but not give the  
desired behaviour?"  That way you will avoid false confidence in specs  
where the behaviour could be broken in the future (perhaps during  
refactoring), but RSpec still reports success.

Ashley

-- 
http://www.patchspace.co.uk/
http://aviewfromafar.net/

Thanks Ashley, you right.
Atenciosamente,

Daniel Lopes  ?  Area Cria??es
Design, Websites e Sistemas Web

Visite:  http://www.areacriacoes.com.br/projects
          http://blog.areacriacoes.com.br/

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
55 (31) 3077-4560  /  55 (31) 8808-8748  /  55 (31) 8737-7501


On Fri, Dec 5, 2008 at 6:41 PM, Ashley Moran
<ashley.moran at patchspace.co.uk>wrote:
>
> On 5 Dec 2008, at 20:26, Daniel Area Cria??es wrote:
>
>  This line is only saying that @properties (assigned[:properties]) have
>> some value ... is that?
>> assigns[:properties].should == :user_properties
>>
>> I can change above to assigns[:properties].should_not be_nill and the
>> semantic value will be the same, right?
>>
>
>
> Ah no, the semantic value is different because this would also pass:
>
>  def index
>    @properties = "vegetable soup"
>  end
>
> Yet that does not implement the same behaviour.
>
> When you write a behaviour example, always ask the question "What
could I
> realistically write that could pass this but not give the desired
> behaviour?"  That way you will avoid false confidence in specs where
the
> behaviour could be broken in the future (perhaps during refactoring), but
> RSpec still reports success.
>
>
> Ashley
>
> --
> http://www.patchspace.co.uk/
> http://aviewfromafar.net/
>
>
>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
>
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