module ActiveSupport::Deprecation::MethodWrapper

# => nil
DEPRECATION WARNING: eee is deprecated and will be removed from MyGem next-release (use zzz instead). (called from irb_binding at (irb):18)
Fred.new.eee

# => [:eee]
custom_deprecator.deprecate_methods(Fred, eee: :zzz)
custom_deprecator = ActiveSupport::Deprecation.new('next-release', 'MyGem')
Using a custom deprecator directly:

# => nil
DEPRECATION WARNING: ddd is deprecated and will be removed from MyGem next-release (use zzz instead). (called from irb_binding at (irb):15)
Fred.new.ddd

# => [:ddd]
ActiveSupport::Deprecation.deprecate_methods(Fred, ddd: :zzz, deprecator: custom_deprecator)
custom_deprecator = ActiveSupport::Deprecation.new('next-release', 'MyGem')
Passing in a custom deprecator:

# => nil
# DEPRECATION WARNING: ccc is deprecated and will be removed from Rails 5.1 (use Bar#ccc instead). (called from irb_binding at (irb):12)
Fred.new.ccc

# => nil
# DEPRECATION WARNING: bbb is deprecated and will be removed from Rails 5.1 (use zzz instead). (called from irb_binding at (irb):11)
Fred.new.bbb

# => nil
# DEPRECATION WARNING: aaa is deprecated and will be removed from Rails 5.1. (called from irb_binding at (irb):10)
Fred.new.aaa

# => Fred
ActiveSupport::Deprecation.deprecate_methods(Fred, :aaa, bbb: :zzz, ccc: 'use Bar#ccc instead')
Using the default deprecator:

end
def eee; end
def ddd; end
def ccc; end
def bbb; end
def aaa; end
class Fred

Declare that a method has been deprecated.

def deprecate_methods(target_module, *method_names)
  options = method_names.extract_options!
  deprecator = options.delete(:deprecator) || self
  method_names += options.keys
  mod = nil
  method_names.each do |method_name|
    message = options[method_name]
    if target_module.method_defined?(method_name) || target_module.private_method_defined?(method_name)
      method = target_module.instance_method(method_name)
      target_module.module_eval do
        redefine_method(method_name) do |*args, &block|
          deprecator.deprecation_warning(method_name, message)
          method.bind_call(self, *args, &block)
        end
        ruby2_keywords(method_name)
      end
    else
      mod ||= Module.new
      mod.module_eval do
        define_method(method_name) do |*args, &block|
          deprecator.deprecation_warning(method_name, message)
          super(*args, &block)
        end
        ruby2_keywords(method_name)
      end
    end
  end
  target_module.prepend(mod) if mod
end