diff options
Diffstat (limited to 'activerecord/lib/active_record/reflection.rb')
-rw-r--r-- | activerecord/lib/active_record/reflection.rb | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb index 0995750ecd..9403273db0 100644 --- a/activerecord/lib/active_record/reflection.rb +++ b/activerecord/lib/active_record/reflection.rb @@ -401,6 +401,16 @@ module ActiveRecord # has_many :tags, through: :taggings # end # + # class Tagging < ActiveRecord::Base + # belongs_to :post + # belongs_to :tag + # end + # + # tags_reflection = Post.reflect_on_association(:tags) + # + # taggings_reflection = tags_reflection.source_reflection + # # => <ActiveRecord::Reflection::AssociationReflection: @macro=:belongs_to, @name=:tag, @active_record=Tagging, @plural_name="tags"> + # def source_reflection @source_reflection ||= source_reflection_names.collect { |name| through_reflection.klass.reflect_on_association(name) }.compact.first end @@ -426,6 +436,17 @@ module ActiveRecord # The chain is built by recursively calling #chain on the source reflection and the through # reflection. The base case for the recursion is a normal association, which just returns # [self] as its #chain. + # + # class Post < ActiveRecord::Base + # has_many :taggings + # has_many :tags, through: :taggings + # end + # + # tags_reflection = Post.reflect_on_association(:tags) + # tags_reflection.chain + # # => [<ActiveRecord::Reflection::ThroughReflection: @macro=:has_many, @name=:tags, @options={:through=>:taggings}, @active_record=Post>, + # <ActiveRecord::Reflection::AssociationReflection: @macro=:has_many, @name=:taggings, @options={}, @active_record=Post>] + # def chain @chain ||= begin chain = source_reflection.chain + through_reflection.chain @@ -496,9 +517,16 @@ module ActiveRecord source_reflection.options[:primary_key] || primary_key(klass || self.klass) end - # Gets an array of possible <tt>:through</tt> source reflection names: + # Gets an array of possible <tt>:through</tt> source reflection names in both singular and plural form. # - # [:singularized, :pluralized] + # class Post < ActiveRecord::Base + # has_many :taggings + # has_many :tags, through: :taggings + # end + # + # tags_reflection = Post.reflect_on_association(:tags) + # tags_reflection.source_reflection_names + # # => [:tag, :tags] # def source_reflection_names @source_reflection_names ||= (options[:source] ? [options[:source]] : [name.to_s.singularize, name]).collect { |n| n.to_sym } |