* test/ruby/test_metaclass.rb: new test case for metaclass hierarchy.

* class.c (make_metametaclass): new function. extracted from
  rb_make_metaclass.

* class.c (rb_make_metaclass): uses make_metametaclass when called for a
  metaclass.

* class.c (rb_singleton_class): creates a meta^(n+2)-class in
  addition to a meta^(n+1)-class when called for a meta^(n)-class.
  This is because the returned meta^(n+1) class must acts as an instance of 
  Class, metaclass of Class, ..., meta^(n+1)-class of Class,
  Module, metaclass of Module, ..., meta^(n+1)-class of Module,
  Object, metaclass of Object, ..., meta^(n+2)-class of Object,
  BasicObject, metaclass of BasicObject, ..., meta^(n+2)-class of
  and BasicObject even when Class, Module, Object or BasicObject has
  not have its meta^(i)-class yet.

git-svn-id: http://svn.ruby-lang.org/repos/ruby/trunk@20747 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 169 insertions, 0 deletions

diff --git a/test/ruby/test_metaclass.rb b/test/ruby/test_metaclass.rb
new file mode 100644
index 000000000..d531cb9dc
--- /dev/null
+++ b/test/ruby/test_metaclass.rb
@@ -0,0 +1,169 @@
+require 'test/unit'
+require_relative 'envutil'
+require '~/dev/metaclass_util/metaclass_util'
+
+class TestMetaclass < Test::Unit::TestCase
+  class Foo; end
+  class Bar < Foo; end
+  class Baz; end
+
+  def setup
+    Object.class_eval do
+      def method_o; end
+    end
+    Module.class_eval do
+      def method_m; end
+    end
+    Class.class_eval do
+      def method_c; end
+    end
+  end
+  def teardown
+    Object.class_eval do
+      remove_method :method_o rescue nil
+    end
+    Module.class_eval do
+      remove_method :method_m rescue nil
+    end
+    Class.class_eval do
+      remove_method :method_c rescue nil
+    end
+    Object.class_eval do
+      class << self
+        remove_method :class_method_o rescue nil
+      end
+    end
+    Module.class_eval do
+      class << self
+        remove_method :class_method_m rescue nil
+      end
+    end
+    Class.class_eval do
+      class << self
+        remove_method :class_method_c rescue nil
+      end
+    end
+    Object.class_eval do
+      class << self
+        class << self
+          remove_method :metaclass_method_o rescue nil
+        end
+      end
+    end
+    Module.class_eval do
+      class << self
+        class << self
+          remove_method :metaclass_method_m rescue nil
+        end
+      end
+    end
+    Class.class_eval do
+      class << self
+        class << self
+          remove_method :metaclass_method_c rescue nil
+        end
+      end
+    end
+  end
+
+  def test_metaclass
+    class << Object
+      def class_method_o; end
+    end
+    class << Foo
+      def class_method_f; end
+    end
+    class << Baz
+      def class_method_b; end
+    end
+    assert_nothing_raised{ Bar.method_o }
+    assert_nothing_raised{ Bar.method_m }
+    assert_nothing_raised{ Bar.method_c }
+    assert_nothing_raised{ Bar.class_method_o }
+    assert_nothing_raised{ Bar.class_method_f }
+    assert_raise(NoMethodError){ Bar.class_method_b }
+
+    class << Module
+      def class_method_m; end
+    end
+    class << Class
+      def class_method_c; end
+    end
+    class << Object
+      class << self
+        def metaclass_method_o; end
+      end
+    end
+    class << Foo
+      class << self
+        def metaclass_method_f; end
+      end
+    end
+    class << Baz
+      class << self
+        def metaclass_method_b; end
+      end
+    end
+    metaclass_of_bar = class << Bar; self end
+    assert_nothing_raised{ metaclass_of_bar.method_o }
+    assert_nothing_raised{ metaclass_of_bar.method_m }
+    assert_nothing_raised{ metaclass_of_bar.method_c }
+    assert_nothing_raised{ metaclass_of_bar.class_method_o }
+    assert_raise(NoMethodError){ metaclass_of_bar.class_method_f }
+    assert_raise(NoMethodError){ metaclass_of_bar.class_method_b }
+    assert_nothing_raised{ metaclass_of_bar.class_method_m }
+    assert_nothing_raised{ metaclass_of_bar.class_method_c }
+    assert_nothing_raised{ metaclass_of_bar.metaclass_method_o }
+    assert_nothing_raised{ metaclass_of_bar.metaclass_method_f }
+    assert_raise(NoMethodError){ metaclass_of_bar.metaclass_method_b }
+
+    class << Module
+      class << self
+        def metaclass_method_m; end
+      end
+    end
+    class << Class
+      class << self
+        def metaclass_method_c; end
+      end
+    end
+    class << Object
+      class << self
+        class << self
+          def metametaclass_method_o; end
+        end
+      end
+    end
+    class << Foo
+      class << self
+        class << self
+          def metametaclass_method_f; end
+        end
+      end
+    end
+    class << Baz
+      class << self
+        class << self
+          def metametaclass_method_b; end
+        end
+      end
+    end
+    metametaclass_of_bar = class << metaclass_of_bar; self end
+    assert_nothing_raised{ metametaclass_of_bar.method_o }
+    assert_nothing_raised{ metametaclass_of_bar.method_m }
+    assert_nothing_raised{ metametaclass_of_bar.method_c }
+    assert_nothing_raised{ metametaclass_of_bar.class_method_o }
+    assert_raise(NoMethodError){ metametaclass_of_bar.class_method_f }
+    assert_raise(NoMethodError){ metametaclass_of_bar.class_method_b }
+    assert_nothing_raised{ metametaclass_of_bar.class_method_m }
+    assert_nothing_raised{ metametaclass_of_bar.class_method_c }
+    assert_nothing_raised{ metametaclass_of_bar.metaclass_method_o }
+    assert_raise(NoMethodError){ metametaclass_of_bar.metaclass_method_f }
+    assert_raise(NoMethodError){ metametaclass_of_bar.metaclass_method_b }
+    assert_nothing_raised{ metametaclass_of_bar.metaclass_method_m }
+    assert_nothing_raised{ metametaclass_of_bar.metaclass_method_c }
+    assert_nothing_raised{ metametaclass_of_bar.metametaclass_method_o }
+    assert_nothing_raised{ metametaclass_of_bar.metametaclass_method_f }
+    assert_raise(NoMethodError){ metametaclass_of_bar.metaclass_method_b }
+  end
+end