[PATCH] Calling count() on a has_many association ignores explicit :include option

Note: this is not the same problem as #9167. That one baffles me, this one's a two-character fix.

I don't understand the significance of :include in a count query. Can you please elaborate ?

Thanks.

In the examples I gave in the ticket description I'm trying to count the number of posts that have no comments. The way to do that is to include the comments table with a join and test for "comments.id is null".

My real-world use case is that I'm attempting to detect products that have an associated object that's several tables away. My (totally renamed) code is:

class Customer < ActiveRecord::Base
  has_many :products
  has_many :unpurchased_products, :class_name => 'Product', :conditions => "line_items.it is not null OR estimates.id is null", :include => {:line_items => {:stores => :estimates} }
end

calling @customer.unpurchased_products works perfectly. But when I want to just display a number of unpurchased products in a shopping cart link at the top of the page I don't want to load all the data as objects. I just want to count it, which is why It's disconcerting that @customer.unpurchased_products.size doesn't work.

So this is a micro-patch that completely solves this behavior by making sure ActiveRecord doesn't clobber the specified :include tables to be joined.

Patch for the 1-2 stable branch

(In [7326]) Don't clobber :includes passed to count on has_many association. Closes #9175 [danger]

(In [7328]) Don't clobber :includes passed to count on has_many association. Closes #9175 [danger]