vendor/rails/activesupport/lib/active_support/core_ext/object/extending.rb

   1 class Object
   2   def remove_subclasses_of(*superclasses) #:nodoc:
   3     Class.remove_class(*subclasses_of(*superclasses))
   4   end
   5
   6   begin
   7     ObjectSpace.each_object(Class.new) {}
   8
   9     # Exclude this class unless it's a subclass of our supers and is defined.
  10     # We check defined? in case we find a removed class that has yet to be
  11     # garbage collected. This also fails for anonymous classes -- please
  12     # submit a patch if you have a workaround.
  13     def subclasses_of(*superclasses) #:nodoc:
  14       subclasses = []
  15
  16       superclasses.each do |sup|
  17         ObjectSpace.each_object(class << sup; self; end) do |k|
  18           if k != sup && (k.name.blank? || eval("defined?(::#{k}) && ::#{k}.object_id == k.object_id"))
  19             subclasses << k
  20           end
  21         end
  22       end
  23
  24       subclasses
  25     end
  26   rescue RuntimeError
  27     # JRuby and any implementations which cannot handle the objectspace traversal
  28     # above fall back to this implementation
  29     def subclasses_of(*superclasses) #:nodoc:
  30       subclasses = []
  31
  32       superclasses.each do |sup|
  33         ObjectSpace.each_object(Class) do |k|
  34           if superclasses.any? { |superclass| k < superclass } &&
  35             (k.name.blank? || eval("defined?(::#{k}) && ::#{k}.object_id == k.object_id"))
  36             subclasses << k
  37           end
  38         end
  39         subclasses.uniq!
  40       end
  41       subclasses
  42     end
  43   end
  44
  45   def extended_by #:nodoc:
  46     ancestors = class << self; ancestors end
  47     ancestors.select { |mod| mod.class == Module } - [ Object, Kernel ]
  48   end
  49
  50   def extend_with_included_modules_from(object) #:nodoc:
  51     object.extended_by.each { |mod| extend mod }
  52   end
  53
  54   unless defined? instance_exec # 1.9
  55     module InstanceExecMethods #:nodoc:
  56     end
  57     include InstanceExecMethods
  58
  59     # Evaluate the block with the given arguments within the context of
  60     # this object, so self is set to the method receiver.
  61     #
  62     # From Mauricio's http://eigenclass.org/hiki/bounded+space+instance_exec
  63     def instance_exec(*args, &block)
  64       begin
  65         old_critical, Thread.critical = Thread.critical, true
  66         n = 0
  67         n += 1 while respond_to?(method_name = "__instance_exec#{n}")
  68         InstanceExecMethods.module_eval { define_method(method_name, &block) }
  69       ensure
  70         Thread.critical = old_critical
  71       end
  72
  73       begin
  74         send(method_name, *args)
  75       ensure
  76         InstanceExecMethods.module_eval { remove_method(method_name) } rescue nil
  77       end
  78     end
  79   end
  80 end