ActiveRecord::Relation reduce by 'OR'

reduce_by_or.rb

require 'active_record/relation'

# Usage
#
# class User
#   scope :foo, -> { where(name: 'foo') }
#   scope :bar, -> { where(name: 'foo') }
# end
#
# > User.foo.or User.bar
#  User Load (0.6ms)  SELECT `users`.* FROM `users` WHERE ((`users`.`name` = 'foo' OR `users`.`name` = 'bar'))
#
module ReduceByOr
  def or other
    w1 = self.where_values.reduce(:and)
    b1 = self.bind_values
    w2 = other.where_values.reduce(:and)
    b2 = other.bind_values

    self.klass.where(w1.or w2).bind(b1 + b2) 
  end 
end
ActiveRecord::Relation.include ReduceByOr