rails polymorphic query

Question

Why is it that

@discussions = Discussion.where(:discussable => @discussable) 

doesn't work. yet this work:

@discussions = Discussion.where(:discussable_id => @discussable.id, :discussable_type => @discussable.class.to_s)

Thanks.

Answer 1

Looks like pull request which fixes this issue was merged into master 1 month ago:

https://github.com/rails/rails/pull/7273

Unfortunately, it will be only released in Rails 4 :(