Search methods for associations

[graywh]

Given

class Parent < ActiveRecord::Base
  scope :current, lambda { where(['lifespan_start <= ?', Date.today]).where(['lifespan_end >= ?', Date.today]) }
  search_methods :current
end

class Child < ActiveRecord::Base
  belongs_to :parent
end

it would be nice to be able to

Child.search({ :parent_current => 1 })

Currently getting an undefined method `parent_current=' error.