variable.c: remove generic ivar support for special constants

Special constants are all frozen since [Feature #8923] and cannot
support ivars.  Remove some unused code we had for supporting them.

* variable.c (special_generic_ivar): remove flag
  (givar_i, rb_mark_generic_ivar_tbl): remove functions
  (rb_free_generic_ivar, rb_ivar_lookup, rb_ivar_delete,
   generic_ivar_set, rb_ivar_set, rb_ivar_defined,
   rb_copy_generic_ivar, rb_ivar_foreach, rb_ivar_count,
   rb_obj_remove_instance_variable):
   adjust for lack of ivar support in special constants
* test/ruby/test_variable.rb: test ivars for special consts
* internal.h: remove rb_mark_generic_ivar_tbl decl
* gc.c (gc_mark_roots): remove rb_mark_generic_ivar_tbl call

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50758 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 18 insertions, 0 deletions

diff --git a/test/ruby/test_variable.rb b/test/ruby/test_variable.rb
index 8f5329bb1c..f04e358e62 100644
--- a/test/ruby/test_variable.rb
+++ b/test/ruby/test_variable.rb
@@ -118,4 +118,22 @@ class TestVariable < Test::Unit::TestCase
       }
     }
   end
+
+  def test_special_constant_ivars
+    [ true, false, :symbol, "dsym#{rand(9999)}".to_sym, 1, 1.0 ].each do |v|
+      assert_empty v.instance_variables
+      msg = "can't modify frozen #{v.class}"
+
+      assert_raise_with_message(RuntimeError, msg) do
+        v.instance_variable_set(:@foo, :bar)
+      end
+
+      assert_nil v.instance_variable_get(:@foo)
+      refute v.instance_variable_defined?(:@foo)
+
+      assert_raise_with_message(RuntimeError, msg) do
+        v.remove_instance_variable(:@foo)
+      end
+    end
+  end
 end