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# frozen_string_literal: true
# This is the parent Association class which defines the variables
# used by all associations.
#
# The hierarchy is defined as follows:
# Association
# - SingularAssociation
# - BelongsToAssociation
# - HasOneAssociation
# - CollectionAssociation
# - HasManyAssociation
module ActiveRecord::Associations::Builder # :nodoc:
class Association #:nodoc:
class << self
attr_accessor :extensions
end
self.extensions = []
VALID_OPTIONS = [:class_name, :anonymous_class, :foreign_key, :validate] # :nodoc:
def self.build(model, name, scope, options, &block)
if model.dangerous_attribute_method?(name)
raise ArgumentError, "You tried to define an association named #{name} on the model #{model.name}, but " \
"this will conflict with a method #{name} already defined by Active Record. " \
"Please choose a different association name."
end
reflection = create_reflection(model, name, scope, options, &block)
define_accessors model, reflection
define_callbacks model, reflection
define_validations model, reflection
reflection
end
def self.create_reflection(model, name, scope, options, &block)
raise ArgumentError, "association names must be a Symbol" unless name.kind_of?(Symbol)
validate_options(options)
extension = define_extensions(model, name, &block)
options[:extend] = [*options[:extend], extension] if extension
scope = build_scope(scope)
ActiveRecord::Reflection.create(macro, name, scope, options, model)
end
def self.build_scope(scope)
if scope && scope.arity == 0
proc { instance_exec(&scope) }
else
scope
end
end
def self.macro
raise NotImplementedError
end
def self.valid_options(options)
VALID_OPTIONS + Association.extensions.flat_map(&:valid_options)
end
def self.validate_options(options)
options.assert_valid_keys(valid_options(options))
end
def self.define_extensions(model, name)
end
def self.define_callbacks(model, reflection)
if dependent = reflection.options[:dependent]
check_dependent_options(dependent)
add_destroy_callbacks(model, reflection)
end
Association.extensions.each do |extension|
extension.build model, reflection
end
end
# Defines the setter and getter methods for the association
# class Post < ActiveRecord::Base
# has_many :comments
# end
#
# Post.first.comments and Post.first.comments= methods are defined by this method...
def self.define_accessors(model, reflection)
mixin = model.generated_association_methods
name = reflection.name
define_readers(mixin, name)
define_writers(mixin, name)
end
def self.define_readers(mixin, name)
mixin.class_eval <<-CODE, __FILE__, __LINE__ + 1
def #{name}
association(:#{name}).reader
end
CODE
end
def self.define_writers(mixin, name)
mixin.class_eval <<-CODE, __FILE__, __LINE__ + 1
def #{name}=(value)
association(:#{name}).writer(value)
end
CODE
end
def self.define_validations(model, reflection)
# noop
end
def self.valid_dependent_options
raise NotImplementedError
end
def self.check_dependent_options(dependent)
unless valid_dependent_options.include? dependent
raise ArgumentError, "The :dependent option must be one of #{valid_dependent_options}, but is :#{dependent}"
end
end
def self.add_destroy_callbacks(model, reflection)
name = reflection.name
model.before_destroy lambda { |o| o.association(name).handle_dependency }
end
private_class_method :build_scope, :macro, :valid_options, :validate_options, :define_extensions,
:define_callbacks, :define_accessors, :define_readers, :define_writers, :define_validations,
:valid_dependent_options, :check_dependent_options, :add_destroy_callbacks
end
end
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