diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/join_dependency/join_part.rb')
-rw-r--r-- | activerecord/lib/active_record/associations/join_dependency/join_part.rb | 67 |
1 files changed, 30 insertions, 37 deletions
diff --git a/activerecord/lib/active_record/associations/join_dependency/join_part.rb b/activerecord/lib/active_record/associations/join_dependency/join_part.rb index 711f7b3ce1..9c6573f913 100644 --- a/activerecord/lib/active_record/associations/join_dependency/join_part.rb +++ b/activerecord/lib/active_record/associations/join_dependency/join_part.rb @@ -1,41 +1,42 @@ module ActiveRecord module Associations class JoinDependency # :nodoc: - # A JoinPart represents a part of a JoinDependency. It is an abstract class, inherited + # A JoinPart represents a part of a JoinDependency. It is inherited # by JoinBase and JoinAssociation. A JoinBase represents the Active Record which # everything else is being joined onto. A JoinAssociation represents an association which # is joining to the base. A JoinAssociation may result in more than one actual join # operations (for example a has_and_belongs_to_many JoinAssociation would result in # two; one for the join table and one for the target table). class JoinPart # :nodoc: + include Enumerable + # The Active Record class which this join part is associated 'about'; for a JoinBase # this is the actual base model, for a JoinAssociation this is the target model of the # association. - attr_reader :active_record + attr_reader :base_klass, :children - delegate :table_name, :column_names, :primary_key, :reflections, :arel_engine, :to => :active_record + delegate :table_name, :column_names, :primary_key, :to => :base_klass - def initialize(active_record) - @active_record = active_record - @cached_record = {} - @column_names_with_alias = nil + def initialize(base_klass, children) + @base_klass = base_klass + @children = children end - def aliased_table - Arel::Nodes::TableAlias.new table, aliased_table_name + def name + reflection.name end - def ==(other) - raise NotImplementedError + def match?(other) + self.class == other.class end - # An Arel::Table for the active_record - def table - raise NotImplementedError + def each(&block) + yield self + children.each { |child| child.each(&block) } end - # The prefix to be used when aliasing columns in the active_record's table - def aliased_prefix + # An Arel::Table for the active_record + def table raise NotImplementedError end @@ -44,33 +45,25 @@ module ActiveRecord raise NotImplementedError end - # The alias for the primary key of the active_record's table - def aliased_primary_key - "#{aliased_prefix}_r0" - end + def extract_record(row, column_names_with_alias) + # This code is performance critical as it is called per row. + # see: https://github.com/rails/rails/pull/12185 + hash = {} - # An array of [column_name, alias] pairs for the table - def column_names_with_alias - unless @column_names_with_alias - @column_names_with_alias = [] + index = 0 + length = column_names_with_alias.length - ([primary_key] + (column_names - [primary_key])).compact.each_with_index do |column_name, i| - @column_names_with_alias << [column_name, "#{aliased_prefix}_r#{i}"] - end + while index < length + column_name, alias_name = column_names_with_alias[index] + hash[column_name] = row[alias_name] + index += 1 end - @column_names_with_alias - end - - def extract_record(row) - Hash[column_names_with_alias.map{|cn, an| [cn, row[an]]}] - end - def record_id(row) - row[aliased_primary_key] + hash end - def instantiate(row) - @cached_record[record_id(row)] ||= active_record.send(:instantiate, extract_record(row)) + def instantiate(row, aliases) + base_klass.instantiate(extract_record(row, aliases)) end end end |