vendor/rails/activesupport/lib/active_support/core_ext/class/removal.rb

   1 class Class #:nodoc:
   2
   3   # Unassociates the class with its subclasses and removes the subclasses
   4   # themselves.
   5   #
   6   #   Integer.remove_subclasses # => [Bignum, Fixnum]
   7   #   Fixnum                    # => NameError: uninitialized constant Fixnum
   8   def remove_subclasses
   9     Object.remove_subclasses_of(self)
  10   end
  11
  12   # Returns an array with the names of the subclasses of +self+ as strings.
  13   #
  14   #   Integer.subclasses # => ["Bignum", "Fixnum"]
  15   def subclasses
  16     Object.subclasses_of(self).map { |o| o.to_s }
  17   end
  18
  19   # Removes the classes in +klasses+ from their parent module.
  20   #
  21   # Ordinary classes belong to some module via a constant. This method computes
  22   # that constant name from the class name and removes it from the module it
  23   # belongs to.
  24   #
  25   #   Object.remove_class(Integer) # => [Integer]
  26   #   Integer                      # => NameError: uninitialized constant Integer
  27   #
  28   # Take into account that in general the class object could be still stored
  29   # somewhere else.
  30   #
  31   #   i = Integer                  # => Integer
  32   #   Object.remove_class(Integer) # => [Integer]
  33   #   Integer                      # => NameError: uninitialized constant Integer
  34   #   i.subclasses                 # => ["Bignum", "Fixnum"]
  35   #   Fixnum.superclass            # => Integer
  36   def remove_class(*klasses)
  37     klasses.flatten.each do |klass|
  38       # Skip this class if there is nothing bound to this name
  39       next unless defined?(klass.name)
  40
  41       basename = klass.to_s.split("::").last
  42       parent = klass.parent
  43
  44       # Skip this class if it does not match the current one bound to this name
  45       next unless parent.const_defined?(basename) && klass = parent.const_get(basename)
  46
  47       parent.instance_eval { remove_const basename } unless parent == klass
  48     end
  49   end
  50 end