```ruby
module Rake
  # ##########################################################################
  # Mixin for creating easily cloned objects.
  #
  module Cloneable
    # Clone an object by making a new object and setting all the instance
    # variables to the same values.
    def dup
      sibling = self.class.new
      instance_variables.each do |ivar|
        value = self.instance_variable_get(ivar)
        new_value = value.clone rescue value
        sibling.instance_variable_set(ivar, new_value)
      end
      sibling.taint if tainted?
      sibling
    end

    def clone
      sibling = dup
      sibling.freeze if frozen?
      sibling
    end
  end
end
```

Move object copying code to initialize_copy method.
user
```ruby
module Rake
  # ##########################################################################
  # Mixin for creating easily cloned objects.
  #
  module Cloneable
    # The hook that invoked by 'clone' and 'dup' methods.
    def initialize_copy(source)
      super
      source.instance_variables.each do |var|
        src_value  = source.instance_variable_get(var)
        value = src_value.clone rescue src_value
        instance_variable_set(var, value)
      end
    end
  end
end
```
assistant