require 'active_support/core_ext/hash/keys' require "set" module ActiveRecord class Relation class HashMerger # :nodoc: attr_reader :relation, :hash def initialize(relation, hash) hash.assert_valid_keys(*Relation::VALUE_METHODS) @relation = relation @hash = hash end def merge Merger.new(relation, other).merge end # Applying values to a relation has some side effects. E.g. # interpolation might take place for where values. So we should # build a relation to merge in rather than directly merging # the values. def other other = Relation.new(relation.klass, relation.table) hash.each { |k, v| if k == :joins if Hash === v other.joins!(v) else other.joins!(*v) end else other.send("#{k}!", v) end } other end end class Merger # :nodoc: attr_reader :relation, :values, :other def initialize(relation, other) if other.default_scoped? && other.klass != relation.klass other = other.with_default_scope end @relation = relation @values = other.values @other = other end NORMAL_VALUES = Relation::SINGLE_VALUE_METHODS + Relation::MULTI_VALUE_METHODS - [:joins, :where, :order, :bind, :reverse_order, :lock, :create_with, :reordering, :from] # :nodoc: def normal_values NORMAL_VALUES end def merge normal_values.each do |name| value = values[name] relation.send("#{name}!", *value) unless value.blank? end merge_multi_values merge_single_values merge_joins relation end private def merge_joins return if values[:joins].blank? if other.klass == relation.klass relation.joins!(*values[:joins]) else joins_dependency, rest = values[:joins].partition do |join| case join when Hash, Symbol, Array true else false end end join_dependency = ActiveRecord::Associations::JoinDependency.new(other.klass, joins_dependency, []) relation.joins! rest join_dependency.join_associations.each do |association| @relation = association.join_relation(relation) end end end def merge_multi_values relation.where_values = merged_wheres relation.bind_values = merged_binds if values[:reordering] # override any order specified in the original relation relation.reorder! values[:order] elsif values[:order] # merge in order_values from r relation.order! values[:order] end relation.extend(*values[:extending]) unless values[:extending].blank? end def merge_single_values relation.from_value = values[:from] unless relation.from_value relation.lock_value = values[:lock] unless relation.lock_value relation.reverse_order_value = values[:reverse_order] unless values[:create_with].blank? relation.create_with_value = (relation.create_with_value || {}).merge(values[:create_with]) end end def merged_binds if values[:bind] (relation.bind_values + values[:bind]).uniq(&:first) else relation.bind_values end end def merged_wheres values[:where] ||= [] if values[:where].empty? || relation.where_values.empty? relation.where_values + values[:where] else # Remove equalities from the existing relation with a LHS which is # present in the relation being merged in. seen = Set.new values[:where].each { |w| if w.respond_to?(:operator) && w.operator == :== seen << w.left end } relation.where_values.reject { |w| w.respond_to?(:operator) && w.operator == :== && seen.include?(w.left) } + values[:where] end end end end end