Rails Module not loading for presenter - ruby-on-rails

Question

Why won't my module load properly when I include it in my presenter class?
My class methods and module methods are not available when loading from rails. The module works when loading out of rails in a single file.
app/presenters/body_parts/method_wrapper.rb
module BodyParts
def self.included(klass)
klass.extend ClassMethods # => Car
end # => :included
module ClassMethods
def set_wheels(*args)
x, *wheel_args = args # => [3], [3]
puts "Wheels class method called with: #{x.to_s}" # => nil, nil
#wheels |= x # => true, true
end # => :set_wheels
class MethodWrapper
attr_reader :klass # => nil
def initialize(klass)
#klass = klass
end # => :initialize
def wrap(method_name)
puts "Wrapping a method"
wrapper_callback(result)
end # => :wrap
end # => :wrap
end # => :wrap
private # => BodyParts
def wrapper_callback(result)
"Wrapped a #{result} in the call back"
end # => :wrapper_callback
end # => :wrapper_callback
app/presenters/car_presenter.rb
class CarPresenter
include BodyParts # => Car
set_wheels 3 # => true
def brand
'Car Brand' # => "Car Brand"
end # => :brand
set_wheels 3 # => true
def title # policy set to 2 for title methods because of the above
'Car Title'
end # => :title
end # => :title
car_presenter = CarPresenter.new # => #<CarPresenter:0x00fe4ed9300>
car_presenter.brand # => "Car Brand"
# >> Wheels class method called with: 3
# >> Wheels class method called with: 3
Binding.pry from CarsPresenter in Rails
[1] pry(CarPresenter)> set_wheels 3
NameError: undefined local variable or method `set_wheels' for CarPresenter:Class
from (pry):12:in `<class:CarPresenter>'
[2] pry(CarPresenter)> BodyParts
=> BodyParts
[3] pry(CarPresenter)> self
=> CarPresenter

Answer 1

Due to the way const loading works in rails, a module BodyParts should be defined in the top level of presenters directory, i.e. in app/presenters/body_parts.rb.rb.
Rails expects app/presenters/body_parts/method_wrapper.rb to define const BodyParts::MethodWrapper,
Read mode in rails guides.