Test for sys._is_immortal in the existing case.

Author: ZeroIntensity

Lib/test/test_capi/test_immortal.py

@@ -1,26 +1,32 @@
 import unittest
 from test.support import import_helper
+import sys
 
 _testcapi = import_helper.import_module('_testcapi')
 _testinternalcapi = import_helper.import_module('_testinternalcapi')
 
 
-class TestUnstableCAPI(unittest.TestCase):
-    def test_immortal(self):
+class TestImmortalAPI(unittest.TestCase):
+    def immortal_checking(self, func):
         # Not extensive
         known_immortals = (True, False, None, 0, ())
         for immortal in known_immortals:
             with self.subTest(immortal=immortal):
-                self.assertTrue(_testcapi.is_immortal(immortal))
+                self.assertTrue(func(immortal))
 
         # Some arbitrary mutable objects
         non_immortals = (object(), self, [object()])
         for non_immortal in non_immortals:
             with self.subTest(non_immortal=non_immortal):
-                self.assertFalse(_testcapi.is_immortal(non_immortal))
+                self.assertFalse(func(non_immortal))
 
+    def test_unstable_c_api(self):
+        self.immortal_checking(_testcapi.is_immortal)
         # CRASHES _testcapi.is_immortal(NULL)
 
+    def test_sys(self):
+        self.immortal_checking(sys._is_immortal)
+
 
 class TestInternalCAPI(unittest.TestCase):