rspec users - Jun 2007 - Testing two interdependent ActiveRecord models

Hello,

In my app, I''d like to test two model object objects that interact  
with each other.  (In my example, a Person can have Contributions.)   
I guess you could say that I''m testing ActiveRecord associations.   
For example, a Person has zero or many Contributions.  A Contribution  
has one or more People.  This is the very basic version, but I think  
it will illustrate the dependency.  (In practice, I''m interested in  
testing these associations because there is some extra logic going on  
that needs testing.)

Here are my observations / questions:
1. Since there are two models, it doesn''t seem quite right to make a  
unit test for this, does it?
2. There is an interaction between the two models.  What is a good  
way to test the interaction?  Do I put some of the testing in  
person_spec.rb and some in contribution_spec.rb?  Or do I create some  
sort of "interaction" spec?
3. I don''t think that an integration test makes sense, because I  
don''t want to test the controller and views.
4. I wonder if mocks or stubs would make sense.  I don''t think I need  
to stub out a particular method (i.e. credit card processing),  
though.  I''m pretty new to mocking, any advice or perspective would  
be helpful.

I would appreciate any feedback -- testing philosophy, and maybe some  
hand waving, if you like. :)

I would also be open to a refactoring / redesign if that will help  
with testing.

Thanks,
-David

Dear geeky, pay-your-debt-up-front-instead-of-later testing guru  
(tell me I''m wrong!)...

I would appreciate if you (twould take a look at my message from a  
few weeks ago, since I didn''t get any replies.  Any comments would  
appreciated -- even if they are "you are barking up the wrong tree"  
-- or "you should read article ____ so that you can rephrase /  
rethink your question"

Thanks,
David

On Jun 8, 2007, at 9:05 AM, David James wrote:
> Hello,
>
> In my app, I''d like to test two model object objects that interact
> with each other.  (In my example, a Person can have Contributions.)
> I guess you could say that I''m testing ActiveRecord associations.
> For example, a Person has zero or many Contributions.  A Contribution
> has one or more People.  This is the very basic version, but I think
> it will illustrate the dependency.  (In practice, I''m interested
in
> testing these associations because there is some extra logic going on
> that needs testing.)
>
> Here are my observations / questions:
> 1. Since there are two models, it doesn''t seem quite right to make
a
> unit test for this, does it?
> 2. There is an interaction between the two models.  What is a good
> way to test the interaction?  Do I put some of the testing in
> person_spec.rb and some in contribution_spec.rb?  Or do I create some
> sort of "interaction" spec?
> 3. I don''t think that an integration test makes sense, because I
> don''t want to test the controller and views.
> 4. I wonder if mocks or stubs would make sense.  I don''t think I
need
> to stub out a particular method (i.e. credit card processing),
> though.  I''m pretty new to mocking, any advice or perspective
would
> be helpful.
>
> I would appreciate any feedback -- testing philosophy, and maybe some
> hand waving, if you like. :)
>
> I would also be open to a refactoring / redesign if that will help
> with testing.
>
> Thanks,
> -David
>
>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
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On Jun 21, 2007, at 3:17 PM, David James wrote:
> Dear geeky, pay-your-debt-up-front-instead-of-later testing guru  
> (tell me I''m wrong!)...
>
> I would appreciate if you (twould take a look at my message from a  
> few weeks ago, since I didn''t get any replies.  Any comments would
> appreciated -- even if they are "you are barking up the wrong
tree"
> -- or "you should read article ____ so that you can rephrase /  
> rethink your question"
>
> Thanks,
> David
>
> On Jun 8, 2007, at 9:05 AM, David James wrote:
>
>> Hello,
>>
>> In my app, I''d like to test two model object objects that
interact
>> with each other.  (In my example, a Person can have Contributions.)
>> I guess you could say that I''m testing ActiveRecord
associations.
>> For example, a Person has zero or many Contributions.  A Contribution
>> has one or more People.  This is the very basic version, but I think
>> it will illustrate the dependency.  (In practice, I''m
interested in
>> testing these associations because there is some extra logic going on
>> that needs testing.)
>>
>> Here are my observations / questions:
>> 1. Since there are two models, it doesn''t seem quite right to
make a
>> unit test for this, does it?
>> 2. There is an interaction between the two models.  What is a good
>> way to test the interaction?  Do I put some of the testing in
>> person_spec.rb and some in contribution_spec.rb?  Or do I create some
>> sort of "interaction" spec?
>> 3. I don''t think that an integration test makes sense, because
I
>> don''t want to test the controller and views.
>> 4. I wonder if mocks or stubs would make sense.  I don''t think
I need
>> to stub out a particular method (i.e. credit card processing),
>> though.  I''m pretty new to mocking, any advice or perspective
would
>> be helpful.
>>
>> I would appreciate any feedback -- testing philosophy, and maybe some
>> hand waving, if you like. :)
As far as I can tell, BDD seems to be higher level than typical  
testing ("Unit testing" - What would the "Unit" be here?). 
So it
would make sense (and you are certainly able) to test both models in  
one "describe" block.  If you want more granular "unit"
testing,
write a person spec and a contributions spec separately (and maybe in  
addition to this).  You may want to watch the Dave Astels video on  
Google Videos relating to this topic:

http://video.google.com/videoplay? 
docid=8135690990081075324&q=Behaviour+Driven+Development



With that said, mocking/stubbing will probably be helpful in this  
shared spec.  Or you could just mock/stub the opposite model of the  
one you are testing (i.e. when testing Person, mock Contributors and  
vise-versa).

For me, though, it''s hard to see why you couldn''t use the
later
method (of mocking the association).  Maybe you could give us  
something a little more concrete and/or post some code?

Hope that helps,

Scott Taylor


>>
>> I would also be open to a refactoring / redesign if that will help
>> with testing.
>>
>> Thanks,
>> -David
>>
>>
>> _______________________________________________
>> rspec-users mailing list
>> rspec-users at rubyforge.org
>> http://rubyforge.org/mailman/listinfo/rspec-users
>
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users