* vm_insnhelper.c (vm_call_method): ensure methods of type

VM_METHOD_TYPE_ATTR_SET are called with 1 argument

* test/ruby/test_module.rb (class TestModule): add test

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41389 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,12 @@
+Tue Jun 18 22:01:00 2013  Charlie Somerville  <charliesome@ruby-lang.org>
+
+	* vm_insnhelper.c (vm_call_method): ensure methods of type
+	  VM_METHOD_TYPE_ATTR_SET are called with 1 argument
+
+	* test/ruby/test_module.rb (class TestModule): add test
+
+	[ruby-core:55543] [Bug #8540]
+
 Tue Jun 18 22:36:23 2013  Masaya Tarui  <tarui@ruby-lang.org>
 
 	* gc.c (gc_profile_record_flag): reason seems like one-hot encoding.

test/ruby/test_module.rb

@@ -1167,6 +1167,14 @@ class TestModule < Test::Unit::TestCase
     assert_equal(1, c.x, bug3406)
   end
 
+  def test_attr_writer_with_no_arguments
+    bug8540 = "[ruby-core:55543]"
+    c = Class.new do
+      attr_writer :foo
+    end
+    assert_raise(ArgumentError) { c.new.send :foo= }
+  end
+
   def test_private_constant
     c = Class.new
     c.const_set(:FOO, "foo")

vm_insnhelper.c

@@ -1773,7 +1773,7 @@ vm_call_method(rb_thread_t *th, rb_control_frame_t *cfp, rb_call_info_t *ci)
 		CI_SET_FASTPATH(ci, vm_call_cfunc, enable_fastpath);
 		return vm_call_cfunc(th, cfp, ci);
 	      case VM_METHOD_TYPE_ATTRSET:{
-		rb_check_arity(ci->argc, 0, 1);
+		rb_check_arity(ci->argc, 1, 1);
 		ci->aux.index = 0;
 		CI_SET_FASTPATH(ci, vm_call_attrset, enable_fastpath && !(ci->flag & VM_CALL_ARGS_SPLAT));
 		return vm_call_attrset(th, cfp, ci);