vm_method.c: fix aliased original name

* vm_method.c (rb_alias): the original name should be properly
  available method_added method, set the name before calling the
  hook.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54035 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 28 insertions, 0 deletions

diff --git a/test/ruby/test_alias.rb b/test/ruby/test_alias.rb
index d5bbce3dda..3fc1bb4000 100644
--- a/test/ruby/test_alias.rb
+++ b/test/ruby/test_alias.rb
@@ -203,4 +203,32 @@ class TestAlias < Test::Unit::TestCase
     assert_equal(obj.method(:bar), obj.method(:foo))
     assert_equal(obj.method(:foo), obj.method(:bar))
   end
+
+  def test_alias_class_method_added
+    name = nil
+    k = Class.new {
+      def foo;end
+      def self.method_added(mid)
+        @name = instance_method(mid).original_name
+      end
+      alias bar foo
+      name = @name
+    }
+    assert_equal(:foo, k.instance_method(:bar).original_name)
+    assert_equal(:foo, name)
+  end
+
+  def test_alias_module_method_added
+    name = nil
+    k = Module.new {
+      def foo;end
+      def self.method_added(mid)
+        @name = instance_method(mid).original_name
+      end
+      alias bar foo
+      name = @name
+    }
+    assert_equal(:foo, k.instance_method(:bar).original_name)
+    assert_equal(:foo, name)
+  end
 end