diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/collection_proxy.rb')
-rw-r--r-- | activerecord/lib/active_record/associations/collection_proxy.rb | 968 |
1 files changed, 915 insertions, 53 deletions
diff --git a/activerecord/lib/active_record/associations/collection_proxy.rb b/activerecord/lib/active_record/associations/collection_proxy.rb index 5eda0387c4..ee8b816ef4 100644 --- a/activerecord/lib/active_record/associations/collection_proxy.rb +++ b/activerecord/lib/active_record/associations/collection_proxy.rb @@ -33,26 +33,812 @@ module ActiveRecord # # is computed directly through SQL and does not trigger by itself the # instantiation of the actual post records. - class CollectionProxy # :nodoc: - alias :proxy_extend :extend + class CollectionProxy < Relation + def initialize(association) #:nodoc: + @association = association + super association.klass, association.klass.arel_table + merge! association.scope + end - instance_methods.each { |m| undef_method m unless m.to_s =~ /^(?:nil\?|send|object_id|to_a)$|^__|^respond_to|proxy_/ } + def target + @association.target + end - delegate :group, :order, :limit, :joins, :where, :preload, :eager_load, :includes, :from, - :lock, :readonly, :having, :pluck, :to => :scoped + def load_target + @association.load_target + end - delegate :target, :load_target, :loaded?, :to => :@association + def loaded? + @association.loaded? + end - delegate :select, :find, :first, :last, - :build, :create, :create!, - :concat, :replace, :delete_all, :destroy_all, :delete, :destroy, :uniq, - :sum, :count, :size, :length, :empty?, - :any?, :many?, :include?, - :to => :@association + ## + # Works in two ways. + # + # *First:* Specify a subset of fields to be selected from the result set. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.select(:name) + # # => [ + # # #<Pet id: nil, name: "Fancy-Fancy">, + # # #<Pet id: nil, name: "Spook">, + # # #<Pet id: nil, name: "Choo-Choo"> + # # ] + # + # person.pets.select([:id, :name]) + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy">, + # # #<Pet id: 2, name: "Spook">, + # # #<Pet id: 3, name: "Choo-Choo"> + # # ] + # + # Be careful because this also means you’re initializing a model + # object with only the fields that you’ve selected. If you attempt + # to access a field that is not in the initialized record you’ll + # receive: + # + # person.pets.select(:name).first.person_id + # # => ActiveModel::MissingAttributeError: missing attribute: person_id + # + # *Second:* You can pass a block so it can be used just like Array#select. + # This build an array of objects from the database for the scope, + # converting them into an array and iterating through them using + # Array#select. + # + # person.pets.select { |pet| pet.name =~ /oo/ } + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.select(:name) { |pet| pet.name =~ /oo/ } + # # => [ + # # #<Pet id: 2, name: "Spook">, + # # #<Pet id: 3, name: "Choo-Choo"> + # # ] + def select(select = nil, &block) + @association.select(select, &block) + end - def initialize(association) - @association = association - Array(association.options[:extend]).each { |ext| proxy_extend(ext) } + ## + # Finds an object in the collection responding to the +id+. Uses the same + # rules as +ActiveRecord::Base.find+. Returns +ActiveRecord::RecordNotFound++ + # error if the object can not be found. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.find(1) # => #<Pet id: 1, name: "Fancy-Fancy", person_id: 1> + # person.pets.find(4) # => ActiveRecord::RecordNotFound: Couldn't find Pet with id=4 + # + # person.pets.find(2) { |pet| pet.name.downcase! } + # # => #<Pet id: 2, name: "fancy-fancy", person_id: 1> + # + # person.pets.find(2, 3) + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + def find(*args, &block) + @association.find(*args, &block) + end + + ## + # Returns the first record, or the first +n+ records, from the collection. + # If the collection is empty, the first form returns +nil+, and the second + # form returns an empty array. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.first # => #<Pet id: 1, name: "Fancy-Fancy", person_id: 1> + # + # person.pets.first(2) + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1> + # # ] + # + # another_person_without.pets # => [] + # another_person_without.pets.first # => nil + # another_person_without.pets.first(3) # => [] + def first(*args) + @association.first(*args) + end + + ## + # Returns the last record, or the last +n+ records, from the collection. + # If the collection is empty, the first form returns +nil+, and the second + # form returns an empty array. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.last # => #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # + # person.pets.last(2) + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # another_person_without.pets # => [] + # another_person_without.pets.last # => nil + # another_person_without.pets.last(3) # => [] + def last(*args) + @association.last(*args) + end + + ## + # Returns a new object of the collection type that has been instantiated + # with +attributes+ and linked to this object, but have not yet been saved. + # You can pass an array of attributes hashes, this will return an array + # with the new objects. + # + # class Person + # has_many :pets + # end + # + # person.pets.build + # # => #<Pet id: nil, name: nil, person_id: 1> + # + # person.pets.build(name: 'Fancy-Fancy') + # # => #<Pet id: nil, name: "Fancy-Fancy", person_id: 1> + # + # person.pets.build([{name: 'Spook'}, {name: 'Choo-Choo'}, {name: 'Brain'}]) + # # => [ + # # #<Pet id: nil, name: "Spook", person_id: 1>, + # # #<Pet id: nil, name: "Choo-Choo", person_id: 1>, + # # #<Pet id: nil, name: "Brain", person_id: 1> + # # ] + # + # person.pets.size # => 5 # size of the collection + # person.pets.count # => 0 # count from database + def build(attributes = {}, options = {}, &block) + @association.build(attributes, options, &block) + end + + ## + # Returns a new object of the collection type that has been instantiated with + # attributes, linked to this object and that has already been saved (if it + # passes the validations). + # + # class Person + # has_many :pets + # end + # + # person.pets.create(name: 'Fancy-Fancy') + # # => #<Pet id: 1, name: "Fancy-Fancy", person_id: 1> + # + # person.pets.create([{name: 'Spook'}, {name: 'Choo-Choo'}]) + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.size # => 3 + # person.pets.count # => 3 + # + # person.pets.find(1, 2, 3) + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + def create(attributes = {}, options = {}, &block) + @association.create(attributes, options, &block) + end + + ## + # Like +create+, except that if the record is invalid, raises an exception. + # + # class Person + # has_many :pets + # end + # + # class Pet + # attr_accessible :name + # validates :name, presence: true + # end + # + # person.pets.create!(name: nil) + # # => ActiveRecord::RecordInvalid: Validation failed: Name can't be blank + def create!(attributes = {}, options = {}, &block) + @association.create!(attributes, options, &block) + end + + ## + # Add one or more records to the collection by setting their foreign keys + # to the association's primary key. Since << flattens its argument list and + # inserts each record, +push+ and +concat+ behave identically. Returns +self+ + # so method calls may be chained. + # + # class Person < ActiveRecord::Base + # pets :has_many + # end + # + # person.pets.size # => 0 + # person.pets.concat(Pet.new(name: 'Fancy-Fancy')) + # person.pets.concat(Pet.new(name: 'Spook'), Pet.new(name: 'Choo-Choo')) + # person.pets.size # => 3 + # + # person.id # => 1 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.concat([Pet.new(name: 'Brain'), Pet.new(name: 'Benny')]) + # person.pets.size # => 5 + def concat(*records) + @association.concat(*records) + end + + ## + # Replace this collection with +other_array+. This will perform a diff + # and delete/add only records that have changed. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets + # # => [#<Pet id: 1, name: "Gorby", group: "cats", person_id: 1>] + # + # other_pets = [Pet.new(name: 'Puff', group: 'celebrities'] + # + # person.pets.replace(other_pets) + # + # person.pets + # # => [#<Pet id: 2, name: "Puff", group: "celebrities", person_id: 1>] + # + # If the supplied array has an incorrect association type, it raises + # an <tt>ActiveRecord::AssociationTypeMismatch</tt> error: + # + # person.pets.replace(["doo", "ggie", "gaga"]) + # # => ActiveRecord::AssociationTypeMismatch: Pet expected, got String + def replace(other_array) + @association.replace(other_array) + end + + ## + # Deletes all the records from the collection. For +has_many+ associations, + # the deletion is done according to the strategy specified by the <tt>:dependent</tt> + # option. Returns an array with the deleted records. + # + # If no <tt>:dependent</tt> option is given, then it will follow the + # default strategy. The default strategy is <tt>:nullify</tt>. This + # sets the foreign keys to <tt>NULL</tt>. For, +has_many+ <tt>:through</tt>, + # the default strategy is +delete_all+. + # + # class Person < ActiveRecord::Base + # has_many :pets # dependent: :nullify option by default + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.delete_all + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.size # => 0 + # person.pets # => [] + # + # Pet.find(1, 2, 3) + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: nil>, + # # #<Pet id: 2, name: "Spook", person_id: nil>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: nil> + # # ] + # + # If it is set to <tt>:destroy</tt> all the objects from the collection + # are removed by calling their +destroy+ method. See +destroy+ for more + # information. + # + # class Person < ActiveRecord::Base + # has_many :pets, dependent: :destroy + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.delete_all + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # Pet.find(1, 2, 3) + # # => ActiveRecord::RecordNotFound + # + # If it is set to <tt>:delete_all</tt>, all the objects are deleted + # *without* calling their +destroy+ method. + # + # class Person < ActiveRecord::Base + # has_many :pets, dependent: :delete_all + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.delete_all + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # Pet.find(1, 2, 3) + # # => ActiveRecord::RecordNotFound + def delete_all + @association.delete_all + end + + ## + # Deletes the records of the collection directly from the database. + # This will _always_ remove the records ignoring the +:dependent+ + # option. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.destroy_all + # + # person.pets.size # => 0 + # person.pets # => [] + # + # Pet.find(1) # => Couldn't find Pet with id=1 + def destroy_all + @association.destroy_all + end + + ## + # Deletes the +records+ supplied and removes them from the collection. For + # +has_many+ associations, the deletion is done according to the strategy + # specified by the <tt>:dependent</tt> option. Returns an array with the + # deleted records. + # + # If no <tt>:dependent</tt> option is given, then it will follow the default + # strategy. The default strategy is <tt>:nullify</tt>. This sets the foreign + # keys to <tt>NULL</tt>. For, +has_many+ <tt>:through</tt>, the default + # strategy is +delete_all+. + # + # class Person < ActiveRecord::Base + # has_many :pets # dependent: :nullify option by default + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.delete(Pet.find(1)) + # # => [#<Pet id: 1, name: "Fancy-Fancy", person_id: 1>] + # + # person.pets.size # => 2 + # person.pets + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # Pet.find(1) + # # => #<Pet id: 1, name: "Fancy-Fancy", person_id: nil> + # + # If it is set to <tt>:destroy</tt> all the +records+ are removed by calling + # their +destroy+ method. See +destroy+ for more information. + # + # class Person < ActiveRecord::Base + # has_many :pets, dependent: :destroy + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.delete(Pet.find(1), Pet.find(3)) + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.size # => 1 + # person.pets + # # => [#<Pet id: 2, name: "Spook", person_id: 1>] + # + # Pet.find(1, 3) + # # => ActiveRecord::RecordNotFound: Couldn't find all Pets with IDs (1, 3) + # + # If it is set to <tt>:delete_all</tt>, all the +records+ are deleted + # *without* calling their +destroy+ method. + # + # class Person < ActiveRecord::Base + # has_many :pets, dependent: :delete_all + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.delete(Pet.find(1)) + # # => [#<Pet id: 1, name: "Fancy-Fancy", person_id: 1>] + # + # person.pets.size # => 2 + # person.pets + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # Pet.find(1) + # # => ActiveRecord::RecordNotFound: Couldn't find Pet with id=1 + # + # You can pass +Fixnum+ or +String+ values, it finds the records + # responding to the +id+ and executes delete on them. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.delete("1") + # # => [#<Pet id: 1, name: "Fancy-Fancy", person_id: 1>] + # + # person.pets.delete(2, 3) + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + def delete(*records) + @association.delete(*records) + end + + ## + # Destroys the +records+ supplied and removes them from the collection. + # This method will _always_ remove record from the database ignoring + # the +:dependent+ option. Returns an array with the removed records. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.destroy(Pet.find(1)) + # # => [#<Pet id: 1, name: "Fancy-Fancy", person_id: 1>] + # + # person.pets.size # => 2 + # person.pets + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.destroy(Pet.find(2), Pet.find(3)) + # # => [ + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.size # => 0 + # person.pets # => [] + # + # Pet.find(1, 2, 3) # => ActiveRecord::RecordNotFound: Couldn't find all Pets with IDs (1, 2, 3) + # + # You can pass +Fixnum+ or +String+ values, it finds the records + # responding to the +id+ and then deletes them from the database. + # + # person.pets.size # => 3 + # person.pets + # # => [ + # # #<Pet id: 4, name: "Benny", person_id: 1>, + # # #<Pet id: 5, name: "Brain", person_id: 1>, + # # #<Pet id: 6, name: "Boss", person_id: 1> + # # ] + # + # person.pets.destroy("4") + # # => #<Pet id: 4, name: "Benny", person_id: 1> + # + # person.pets.size # => 2 + # person.pets + # # => [ + # # #<Pet id: 5, name: "Brain", person_id: 1>, + # # #<Pet id: 6, name: "Boss", person_id: 1> + # # ] + # + # person.pets.destroy(5, 6) + # # => [ + # # #<Pet id: 5, name: "Brain", person_id: 1>, + # # #<Pet id: 6, name: "Boss", person_id: 1> + # # ] + # + # person.pets.size # => 0 + # person.pets # => [] + # + # Pet.find(4, 5, 6) # => ActiveRecord::RecordNotFound: Couldn't find all Pets with IDs (4, 5, 6) + def destroy(*records) + @association.destroy(*records) + end + + ## + # Specifies whether the records should be unique or not. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.select(:name) + # # => [ + # # #<Pet name: "Fancy-Fancy">, + # # #<Pet name: "Fancy-Fancy"> + # # ] + # + # person.pets.select(:name).uniq + # # => [#<Pet name: "Fancy-Fancy">] + def uniq + @association.uniq + end + + ## + # Count all records using SQL. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.count # => 3 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + def count(column_name = nil, options = {}) + @association.count(column_name, options) + end + + ## + # Returns the size of the collection. If the collection hasn't been loaded, + # it executes a <tt>SELECT COUNT(*)</tt> query. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.size # => 3 + # # executes something like SELECT COUNT(*) FROM "pets" WHERE "pets"."person_id" = 1 + # + # person.pets # This will execute a SELECT * FROM query + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + # + # person.pets.size # => 3 + # # Because the collection is already loaded, this will behave like + # # collection.size and no SQL count query is executed. + def size + @association.size + end + + ## + # Returns the size of the collection calling +size+ on the target. + # If the collection has been already loaded, +length+ and +size+ are + # equivalent. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.length # => 3 + # # executes something like SELECT "pets".* FROM "pets" WHERE "pets"."person_id" = 1 + # + # # Because the collection is loaded, you can + # # call the collection with no additional queries: + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] + def length + @association.length + end + + ## + # Returns +true+ if the collection is empty. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.count # => 1 + # person.pets.empty? # => false + # + # person.pets.delete_all + # + # person.pets.count # => 0 + # person.pets.empty? # => true + def empty? + @association.empty? + end + + ## + # Returns +true+ if the collection is not empty. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.count # => 0 + # person.pets.any? # => false + # + # person.pets << Pet.new(name: 'Snoop') + # person.pets.count # => 0 + # person.pets.any? # => true + # + # You can also pass a block to define criteria. The behaviour + # is the same, it returns true if the collection based on the + # criteria is not empty. + # + # person.pets + # # => [#<Pet name: "Snoop", group: "dogs">] + # + # person.pets.any? do |pet| + # pet.group == 'cats' + # end + # # => false + # + # person.pets.any? do |pet| + # pet.group == 'dogs' + # end + # # => true + def any?(&block) + @association.any?(&block) + end + + ## + # Returns true if the collection has more than one record. + # Equivalent to <tt>collection.size > 1</tt>. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.count #=> 1 + # person.pets.many? #=> false + # + # person.pets << Pet.new(name: 'Snoopy') + # person.pets.count #=> 2 + # person.pets.many? #=> true + # + # You can also pass a block to define criteria. The + # behaviour is the same, it returns true if the collection + # based on the criteria has more than one record. + # + # person.pets + # # => [ + # # #<Pet name: "Gorby", group: "cats">, + # # #<Pet name: "Puff", group: "cats">, + # # #<Pet name: "Snoop", group: "dogs"> + # # ] + # + # person.pets.many? do |pet| + # pet.group == 'dogs' + # end + # # => false + # + # person.pets.many? do |pet| + # pet.group == 'cats' + # end + # # => true + def many?(&block) + @association.many?(&block) + end + + ## + # Returns +true+ if the given object is present in the collection. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets # => [#<Pet id: 20, name: "Snoop">] + # + # person.pets.include?(Pet.find(20)) # => true + # person.pets.include?(Pet.find(21)) # => false + def include?(record) + @association.include?(record) end alias_method :new, :build @@ -61,67 +847,143 @@ module ActiveRecord @association end - def scoped + # We don't want this object to be put on the scoping stack, because + # that could create an infinite loop where we call an @association + # method, which gets the current scope, which is this object, which + # delegates to @association, and so on. + def scoping + @association.scope.scoping { yield } + end + + # Returns a <tt>Relation</tt> object for the records in this association + def scope association = @association - association.scoped.extending do + + @association.scope.extending! do define_method(:proxy_association) { association } end end - def respond_to?(name, include_private = false) - super || - (load_target && target.respond_to?(name, include_private)) || - proxy_association.klass.respond_to?(name, include_private) - end - - def method_missing(method, *args, &block) - match = DynamicFinderMatch.match(method) - if match && match.instantiator? - send(:find_or_instantiator_by_attributes, match, match.attribute_names, *args) do |r| - proxy_association.send :set_owner_attributes, r - proxy_association.send :add_to_target, r - yield(r) if block_given? - end - - elsif target.respond_to?(method) || (!proxy_association.klass.respond_to?(method) && Class.respond_to?(method)) - if load_target - if target.respond_to?(method) - target.send(method, *args, &block) - else - begin - super - rescue NoMethodError => e - raise e, e.message.sub(/ for #<.*$/, " via proxy for #{target}") - end - end - end - - else - scoped.readonly(nil).send(method, *args, &block) - end - end + # :nodoc: + alias spawn scope - # Forwards <tt>===</tt> explicitly to the \target because the instance method - # removal above doesn't catch it. Loads the \target if needed. - def ===(other) - other === load_target + # Equivalent to <tt>Array#==</tt>. Returns +true+ if the two arrays + # contain the same number of elements and if each element is equal + # to the corresponding element in the other array, otherwise returns + # +false+. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1> + # # ] + # + # other = person.pets.to_ary + # + # person.pets == other + # # => true + # + # other = [Pet.new(id: 1), Pet.new(id: 2)] + # + # person.pets == other + # # => false + def ==(other) + load_target == other end + # Returns a new array of objects from the collection. If the collection + # hasn't been loaded, it fetches the records from the database. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets + # # => [ + # # #<Pet id: 4, name: "Benny", person_id: 1>, + # # #<Pet id: 5, name: "Brain", person_id: 1>, + # # #<Pet id: 6, name: "Boss", person_id: 1> + # # ] + # + # other_pets = person.pets.to_ary + # # => [ + # # #<Pet id: 4, name: "Benny", person_id: 1>, + # # #<Pet id: 5, name: "Brain", person_id: 1>, + # # #<Pet id: 6, name: "Boss", person_id: 1> + # # ] + # + # other_pets.replace([Pet.new(name: 'BooGoo')]) + # + # other_pets + # # => [#<Pet id: nil, name: "BooGoo", person_id: 1>] + # + # person.pets + # # This is not affected by replace + # # => [ + # # #<Pet id: 4, name: "Benny", person_id: 1>, + # # #<Pet id: 5, name: "Brain", person_id: 1>, + # # #<Pet id: 6, name: "Boss", person_id: 1> + # # ] def to_ary load_target.dup end alias_method :to_a, :to_ary + # Adds one or more +records+ to the collection by setting their foreign keys + # to the association‘s primary key. Returns +self+, so several appends may be + # chained together. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets.size # => 0 + # person.pets << Pet.new(name: 'Fancy-Fancy') + # person.pets << [Pet.new(name: 'Spook'), Pet.new(name: 'Choo-Choo')] + # person.pets.size # => 3 + # + # person.id # => 1 + # person.pets + # # => [ + # # #<Pet id: 1, name: "Fancy-Fancy", person_id: 1>, + # # #<Pet id: 2, name: "Spook", person_id: 1>, + # # #<Pet id: 3, name: "Choo-Choo", person_id: 1> + # # ] def <<(*records) proxy_association.concat(records) && self end alias_method :push, :<< + # Equivalent to +delete_all+. The difference is that returns +self+, instead + # of an array with the deleted objects, so methods can be chained. See + # +delete_all+ for more information. def clear delete_all self end + # Reloads the collection from the database. Returns +self+. + # Equivalent to <tt>collection(true)</tt>. + # + # class Person < ActiveRecord::Base + # has_many :pets + # end + # + # person.pets # fetches pets from the database + # # => [#<Pet id: 1, name: "Snoop", group: "dogs", person_id: 1>] + # + # person.pets # uses the pets cache + # # => [#<Pet id: 1, name: "Snoop", group: "dogs", person_id: 1>] + # + # person.pets.reload # fetches pets from the database + # # => [#<Pet id: 1, name: "Snoop", group: "dogs", person_id: 1>] + # + # person.pets(true) # fetches pets from the database + # # => [#<Pet id: 1, name: "Snoop", group: "dogs", person_id: 1>] def reload proxy_association.reload self |