gitlab-org--gitlab-foss/lib/gitlab/patch/prependable.rb

65 lines
1.7 KiB
Ruby

# frozen_string_literal: true
# We're patching `ActiveSupport::Concern` in
# config/initializers/0_as_concern.rb
#
# We want to patch `ActiveSupport::Concern` for two reasons:
# 1. Allow defining class methods via: `class_methods` method
# 2. Allow `prepended do; end` work like `included do; end`
# If we don't need anything above, we don't need this patch nor the concern!
# rubocop:disable Gitlab/ModuleWithInstanceVariables
module Gitlab
module Patch
module Prependable
class MultiplePrependedBlocks < StandardError
def initialize
super "Cannot define multiple 'prepended' blocks for a Concern"
end
end
def prepend_features(base)
return false if prepended?(base)
super
if const_defined?(:ClassMethods)
klass_methods = const_get(:ClassMethods, false)
base.singleton_class.prepend klass_methods
base.instance_variable_set(:@_prepended_class_methods, klass_methods)
end
if instance_variable_defined?(:@_prepended_block)
base.class_eval(&@_prepended_block)
end
true
end
def class_methods
super
if instance_variable_defined?(:@_prepended_class_methods)
const_get(:ClassMethods, false).prepend @_prepended_class_methods
end
end
def prepended(base = nil, &block)
if base.nil?
raise MultiplePrependedBlocks if
instance_variable_defined?(:@_prepended_block)
@_prepended_block = block
else
super
end
end
def prepended?(base)
index = base.ancestors.index(base)
base.ancestors[0...index].index(self)
end
end
end
end