Rails - Nov 2007 - Model Callback.rb insidiousally breaks other models

I''ve run into an odd case where a model called "Callback"
breaks
ActiveRecord::Callbacks, for models other then itself.

It''s understandable if Callback is a model name I shouldn''t
have used,
but its rather insidious in that it works just fine on its own, but
breaks when "belongs_to" from other models includes it.

The following is how to duplicate this, and the results I''m getting.
-------
echo "create database a_development" | mysql -u root ; rails a;cd a;
ruby script/generate model callback;ruby script/generate model
example;rake db:migrate

Edit  app/model/example.rb
{{{
class Example < ActiveRecord::Base
        belongs_to :callback # This line breaks ActiveRecord::Callbacks
for Example.rb
        def before_create
                puts "#{self.class.name} :: This should say something,
but doesn''t"
        end

        def after_create
                puts "#{self.class.name} :: after_create says nothing"
        end

        def before_save
                puts "#{self.class.name} :: before_save says nothing"
        end
        def after_save
                puts "#{self.class.name} :: after_save says nothing"
        end
        def validate
                puts "#{self.class.name} :: validate works"
        end
end
}}}
Edit  app/model/callback.rb
{{{
class Callback < ActiveRecord::Base
        def before_create
                puts "#{self.class.name} :: before_create "
        end

        def after_create
                puts "#{self.class.name} :: after_create "
        end

        def before_save
                puts "#{self.class.name} :: before_save "
        end
        def after_save
                puts "#{self.class.name} :: after_save "
        end
        def validate
                puts "#{self.class.name} :: validate works"
        end
end
}}}
ruby script/console
>> e = Example.new
=> #<Example:0x3268c04 @new_record=true,
@attributes={}>
>> e.save
Example :: validate works
=> true
>> c = Callback.new
=> #<Callback:0x3210cac @new_record=true,
@attributes={}>
>> c.save
Callback :: validate works
Callback :: before_save
Callback :: before_create
Callback :: after_create
Callback :: after_save
=> true
>> 

So it looks like Callback.rb callbacks work, but Example.rb callbacks
don''t.
If I comment out the ":belongs_to :callback" then callbacks work for
Example.rb

Not really sure what to make of this, other then don''t use any name
that
ActiveRecord makes use of.
-- 
Posted via http://www.ruby-forum.com/.

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On 8 Nov 2007, at 18:37, David Harkness wrote:
>
> So it looks like Callback.rb callbacks work, but Example.rb callbacks
> don''t.
> If I comment out the ":belongs_to :callback" then callbacks work
for
> Example.rb
>
> Not really sure what to make of this, other then don''t use any
name
> that
> ActiveRecord makes use of.
There is a (private) method on ActiveRecord::Base called callback (in  
callbacks.rb) which is central to callbacks (callback(:foo) calls the  
callbacks defined for :foo, where :foo is something  
like :after_validation, :before_save etc...).
When you say belongs_to :callback, that defines a new method callback  
(which returns the associated object), but which overwrites the  
earlier definition, stopping callbacks from working.

Fred

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