Backout c89febab4648 following private feedback by Guido.

(Issue #17807: Generators can now be finalized even when they are part of a reference cycle)

Lib/test/test_generators.py

@@ -1,55 +1,3 @@
-import gc
-import sys
-import unittest
-import weakref
-
-from test import support
-
-
-class FinalizationTest(unittest.TestCase):
-
-    def test_frame_resurrect(self):
-        # A generator frame can be resurrected by a generator's finalization.
-        def gen():
-            nonlocal frame
-            try:
-                yield
-            finally:
-                frame = sys._getframe()
-
-        g = gen()
-        wr = weakref.ref(g)
-        next(g)
-        del g
-        support.gc_collect()
-        self.assertIs(wr(), None)
-        self.assertTrue(frame)
-        del frame
-        support.gc_collect()
-
-    def test_refcycle(self):
-        # A generator caught in a refcycle gets finalized anyway.
-        old_garbage = gc.garbage[:]
-        finalized = False
-        def gen():
-            nonlocal finalized
-            try:
-                g = yield
-                yield 1
-            finally:
-                finalized = True
-
-        g = gen()
-        next(g)
-        g.send(g)
-        self.assertGreater(sys.getrefcount(g), 2)
-        self.assertFalse(finalized)
-        del g
-        support.gc_collect()
-        self.assertTrue(finalized)
-        self.assertEqual(gc.garbage, old_garbage)
-
-
 tutorial_tests = """
 Let's try a simple generator:
 
@@ -1932,7 +1880,6 @@ __test__ = {"tut":      tutorial_tests,
 # so this works as expected in both ways of running regrtest.
 def test_main(verbose=None):
     from test import support, test_generators
-    support.run_unittest(__name__)
     support.run_doctest(test_generators, verbose)
 
 # This part isn't needed for regrtest, but for running the test directly.