add_class

# File lib/rdoc/context.rb, line 283
  def add_class class_type, given_name, superclass = '::Object'
    # superclass +nil+ is passed by the C parser in the following cases:
    # - registering Object in 1.8 (correct)
    # - registering BasicObject in 1.9 (correct)
    # - registering RubyVM in 1.9 in iseq.c (incorrect: < Object in vm.c)
    #
    # If we later find a superclass for a registered class with a nil
    # superclass, we must honor it.

    # find the name & enclosing context
    if given_name =~ /^:+(\w+)$/ then
      full_name = $1
      enclosing = top_level
      name = full_name.split(/:+/).last
    else
      full_name = child_name given_name

      if full_name =~ /^(.+)::(\w+)$/ then
        name = $2
        ename = $1
        enclosing = @store.classes_hash[ename] || @store.modules_hash[ename]
        # HACK: crashes in actionpack/lib/action_view/helpers/form_helper.rb (metaprogramming)
        unless enclosing then
          # try the given name at top level (will work for the above example)
          enclosing = @store.classes_hash[given_name] ||
                      @store.modules_hash[given_name]
          return enclosing if enclosing
          # not found: create the parent(s)
          names = ename.split('::')
          enclosing = self
          names.each do |n|
            enclosing = enclosing.classes_hash[n] ||
                        enclosing.modules_hash[n] ||
                        enclosing.add_module(RDoc::NormalModule, n)
          end
        end
      else
        name = full_name
        enclosing = self
      end
    end

    # fix up superclass
    if full_name == 'BasicObject' then
      superclass = nil
    elsif full_name == 'Object' then
      superclass = defined?(::BasicObject) ? '::BasicObject' : nil
    end

    # find the superclass full name
    if superclass then
      if superclass =~ /^:+/ then
        superclass = $' #'
      else
        if superclass =~ /^(\w+):+(.+)$/ then
          suffix = $2
          mod = find_module_named($1)
          superclass = mod.full_name + '::' + suffix if mod
        else
          mod = find_module_named(superclass)
          superclass = mod.full_name if mod
        end
      end

      # did we believe it was a module?
      mod = @store.modules_hash.delete superclass

      upgrade_to_class mod, RDoc::NormalClass, mod.parent if mod

      # e.g., Object < Object
      superclass = nil if superclass == full_name
    end

    klass = @store.classes_hash[full_name]

    if klass then
      # if TopLevel, it may not be registered in the classes:
      enclosing.classes_hash[name] = klass

      # update the superclass if needed
      if superclass then
        existing = klass.superclass
        existing = existing.full_name unless existing.is_a?(String) if existing
        if existing.nil? ||
           (existing == 'Object' && superclass != 'Object') then
          klass.superclass = superclass
        end
      end
    else
      # this is a new class
      mod = @store.modules_hash.delete full_name

      if mod then
        klass = upgrade_to_class mod, RDoc::NormalClass, enclosing

        klass.superclass = superclass unless superclass.nil?
      else
        klass = class_type.new name, superclass

        enclosing.add_class_or_module(klass, enclosing.classes_hash,
                                      @store.classes_hash)
      end
    end

    klass.parent = self

    klass
  end