bpo-40334: Rename PyConfig.use_peg to _use_peg_parser (GH-19670)
* Rename PyConfig.use_peg to _use_peg_parser
* Document PyConfig._use_peg_parser and mark it a deprecated
* Mark -X oldparser option and PYTHONOLDPARSER env var as deprecated
in the documentation.
* Add use_old_parser() and skip_if_new_parser() to test.support
* Remove sys.flags.use_peg: use_old_parser() uses
_testinternalcapi.get_configs() instead.
* Enhance test_embed tests
* subprocess._args_from_interpreter_flags() copies -X oldparser
diff --git a/Lib/test/test_flufl.py b/Lib/test/test_flufl.py
index 297a8aa..35ab934 100644
--- a/Lib/test/test_flufl.py
+++ b/Lib/test/test_flufl.py
@@ -1,9 +1,10 @@
import __future__
import unittest
import sys
+from test import support
-@unittest.skipIf(sys.flags.use_peg, "Not supported by pegen yet")
+@support.skip_if_new_parser("Not supported by pegen yet")
class FLUFLTests(unittest.TestCase):
def test_barry_as_bdfl(self):