Finder :include assoc with same name as key fail on Postgres

On Postgres when calling find on a model with an :include that contains an association with the same name as it's key an exception is raised:

>> Project.find(:all, :include => 'created_by')

=> Message: <"PGError: ERROR: invalid input syntax for integer: \"#<Person:0x19e0038>\"\n: SELECT * FROM \"people\" WHERE (\"people\".id IN (E'#<Person:0x19e0038>')) ">

The basic setup is as follows:

create_table :projects, :force => true do |t|

t.string :name

t.string :type

t.integer :created_by

end

class Project < ActiveRecord::Base

belongs_to :created_by, :class_name => 'Person', :foreign_key => 'created_by'

...

end

This largely effects people who have used created_by, updated_by in their models. See: http://wiki.rubyonrails.org/rail...

However there is likely to be other edge cases

I have attached the failing test case and working fix as a patch.

Notes:

1) An argument against this patch could be that best practice should be to use a column named created_by_id instead. However I would probably favor a deprecation notice / warning over this to begin with.

2) This currently only affects Postgres and not MySQL. Given both adapters use the same code fix it suggests there maybe a deeper issue present.