require 'active_support/core_ext/object/blank'
require 'active_support/core_ext/hash/except'
require 'active_support/core_ext/hash/slice'
require 'active_record/relation/merger'
module ActiveRecord
module SpawnMethods
# This is overridden by Associations::CollectionProxy
def spawn #:nodoc:
clone
end
# Merges in the conditions from other, if other is an ActiveRecord::Relation.
# Returns an array representing the intersection of the resulting records with other, if other is an array.
#
# ==== Examples
#
# Post.where(:published => true).joins(:comments).merge( Comment.where(:spam => false) )
# # Performs a single join query with both where conditions.
#
# recent_posts = Post.order('created_at DESC').first(5)
# Post.where(:published => true).merge(recent_posts)
# # Returns the intersection of all published posts with the 5 most recently created posts.
# # (This is just an example. You'd probably want to do this with a single query!)
#
def merge(other)
if other.is_a?(Array)
to_a & other
elsif other
spawn.merge!(other)
else
self
end
end
def merge!(other)
klass = other.is_a?(Hash) ? Relation::HashMerger : Relation::Merger
klass.new(self, other).merge
end
# Removes from the query the condition(s) specified in +skips+.
#
# Example:
#
# Post.order('id asc').except(:order) # discards the order condition
# Post.where('id > 10').order('id asc').except(:where) # discards the where condition but keeps the order
#
def except(*skips)
result = Relation.new(klass, table, values.except(*skips))
result.default_scoped = default_scoped
result.extend(*extending_values) if extending_values.any?
result
end
# Removes any condition from the query other than the one(s) specified in +onlies+.
#
# Example:
#
# Post.order('id asc').only(:where) # discards the order condition
# Post.order('id asc').only(:where, :order) # uses the specified order
#
def only(*onlies)
result = Relation.new(klass, table, values.slice(*onlies))
result.default_scoped = default_scoped
result.extend(*extending_values) if extending_values.any?
result
end
end
end