text: from test import support
  from test.support.script_helper import assert_python_ok, assert_python_failure
  import builtins
  import codecs
  import gc
  import locale
  import operator
  import os
  import struct
  import subprocess
  import sys
  import sysconfig
  import test.support
  import textwrap
  import unittest
  import warnings
  
  
  # count the number of test runs, used to create unique
  # strings to intern in test_intern()
  INTERN_NUMRUNS = 0
  
  
  class DisplayHookTest(unittest.TestCase):
  
      def test_original_displayhook(self):
          dh = sys.__displayhook__
  
          with support.captured_stdout() as out:
              dh(42)
  
          self.assertEqual(out.getvalue(), "42\n")
          self.assertEqual(builtins._, 42)
  
          del builtins._
  
          with support.captured_stdout() as out:
              dh(None)
  
          self.assertEqual(out.getvalue(), "")
          self.assertTrue(not hasattr(builtins, "_"))
  
          # sys.displayhook() requires arguments
          self.assertRaises(TypeError, dh)
  
          stdout = sys.stdout
          try:
              del sys.stdout
              self.assertRaises(RuntimeError, dh, 42)
          finally:
              sys.stdout = stdout
  
      def test_lost_displayhook(self):
          displayhook = sys.displayhook
          try:
              del sys.displayhook
              code = compile("42", "<string>", "single")
              self.assertRaises(RuntimeError, eval, code)
          finally:
              sys.displayhook = displayhook
  
      def test_custom_displayhook(self):
          def baddisplayhook(obj):
              raise ValueError
  
          with support.swap_attr(sys, 'displayhook', baddisplayhook):
              code = compile("42", "<string>", "single")
              self.assertRaises(ValueError, eval, code)
  
  
  class ExceptHookTest(unittest.TestCase):
  
      def test_original_excepthook(self):
          try:
              raise ValueError(42)
          except ValueError as exc:
              with support.captured_stderr() as err:
                  sys.__excepthook__(*sys.exc_info())
  
          self.assertTrue(err.getvalue().endswith("ValueError: 42\n"))
  
          self.assertRaises(TypeError, sys.__excepthook__)
  
      def test_excepthook_bytes_filename(self):
          # bpo-37467: sys.excepthook() must not crash if a filename
          # is a bytes string
          with warnings.catch_warnings():
              warnings.simplefilter('ignore', BytesWarning)
  
              try:
                  raise SyntaxError("msg", (b"bytes_filename", 123, 0, "text"))
              except SyntaxError as exc:
                  with support.captured_stderr() as err:
                      sys.__excepthook__(*sys.exc_info())
  
          err = err.getvalue()
          self.assertIn("""  File "b'bytes_filename'", line 123\n""", err)
          self.assertIn("""    text\n""", err)
          self.assertTrue(err.endswith("SyntaxError: msg\n"))
  
      def test_excepthook(self):
          with test.support.captured_output("stderr") as stderr:
              sys.excepthook(1, '1', 1)
          self.assertTrue("TypeError: print_exception(): Exception expected for " \
                           "value, str found" in stderr.getvalue())
  
      # FIXME: testing the code for a lost or replaced excepthook in
      # Python/pythonrun.c::PyErr_PrintEx() is tricky.
  
  
  class SysModuleTest(unittest.TestCase):
  
      def tearDown(self):
          test.support.reap_children()
  
      def test_exit(self):
          # call with two arguments
          self.assertRaises(TypeError, sys.exit, 42, 42)
  
          # call without argument
          with self.assertRaises(SystemExit) as cm:
              sys.exit()
          self.assertIsNone(cm.exception.code)
  
          rc, out, err = assert_python_ok('-c', 'import sys; sys.exit()')
          self.assertEqual(rc, 0)
          self.assertEqual(out, b'')
          self.assertEqual(err, b'')
  
          # call with integer argument
          with self.assertRaises(SystemExit) as cm:
              sys.exit(42)
          self.assertEqual(cm.exception.code, 42)
  
          # call with tuple argument with one entry
          # entry will be unpacked
          with self.assertRaises(SystemExit) as cm:
              sys.exit((42,))
          self.assertEqual(cm.exception.code, 42)
  
          # call with string argument
          with self.assertRaises(SystemExit) as cm:
              sys.exit("exit")
          self.assertEqual(cm.exception.code, "exit")
  
          # call with tuple argument with two entries
          with self.assertRaises(SystemExit) as cm:
              sys.exit((17, 23))
          self.assertEqual(cm.exception.code, (17, 23))
  
          # test that the exit machinery handles SystemExits properly
          rc, out, err = assert_python_failure('-c', 'raise SystemExit(47)')
          self.assertEqual(rc, 47)
          self.assertEqual(out, b'')
          self.assertEqual(err, b'')
  
          def check_exit_message(code, expected, **env_vars):
              rc, out, err = assert_python_failure('-c', code, **env_vars)
              self.assertEqual(rc, 1)
              self.assertEqual(out, b'')
              self.assertTrue(err.startswith(expected),
                  "%s doesn't start with %s" % (ascii(err), ascii(expected)))
  
          # test that stderr buffer is flushed before the exit message is written
          # into stderr
          check_exit_message(
              r'import sys; sys.stderr.write("unflushed,"); sys.exit("message")',
              b"unflushed,message")
  
          # test that the exit message is written with backslashreplace error
          # handler to stderr
          check_exit_message(
              r'import sys; sys.exit("surrogates:\uDCFF")',
              b"surrogates:\\udcff")
  
          # test that the unicode message is encoded to the stderr encoding
          # instead of the default encoding (utf8)
          check_exit_message(
              r'import sys; sys.exit("h\xe9")',
              b"h\xe9", PYTHONIOENCODING='latin-1')
  
      def test_getdefaultencoding(self):
          self.assertRaises(TypeError, sys.getdefaultencoding, 42)
          # can't check more than the type, as the user might have changed it
          self.assertIsInstance(sys.getdefaultencoding(), str)
  
      # testing sys.settrace() is done in test_sys_settrace.py
      # testing sys.setprofile() is done in test_sys_setprofile.py
  
      def test_setcheckinterval(self):
          with warnings.catch_warnings():
              warnings.simplefilter("ignore")
              self.assertRaises(TypeError, sys.setcheckinterval)
              orig = sys.getcheckinterval()
              for n in 0, 100, 120, orig: # orig last to restore starting state
                  sys.setcheckinterval(n)
                  self.assertEqual(sys.getcheckinterval(), n)
  
      def test_switchinterval(self):
          self.assertRaises(TypeError, sys.setswitchinterval)
          self.assertRaises(TypeError, sys.setswitchinterval, "a")
          self.assertRaises(ValueError, sys.setswitchinterval, -1.0)
          self.assertRaises(ValueError, sys.setswitchinterval, 0.0)
          orig = sys.getswitchinterval()
          # sanity check
          self.assertTrue(orig < 0.5, orig)
          try:
              for n in 0.00001, 0.05, 3.0, orig:
                  sys.setswitchinterval(n)
                  self.assertAlmostEqual(sys.getswitchinterval(), n)
          finally:
              sys.setswitchinterval(orig)
  
      def test_recursionlimit(self):
          self.assertRaises(TypeError, sys.getrecursionlimit, 42)
          oldlimit = sys.getrecursionlimit()
          self.assertRaises(TypeError, sys.setrecursionlimit)
          self.assertRaises(ValueError, sys.setrecursionlimit, -42)
          sys.setrecursionlimit(10000)
          self.assertEqual(sys.getrecursionlimit(), 10000)
          sys.setrecursionlimit(oldlimit)
  
      @unittest.hasInfiniteRecursion
      def test_recursionlimit_recovery(self):
          if hasattr(sys, 'gettrace') and sys.gettrace():
              self.skipTest('fatal error if run with a trace function')
  
          oldlimit = sys.getrecursionlimit()
          def f():
              f()
          try:
              for depth in (10, 25, 50, 75, 100, 250, 1000):
                  try:
                      sys.setrecursionlimit(depth)
                  except RecursionError:
                      # Issue #25274: The recursion limit is too low at the
                      # current recursion depth
                      continue
  
                  # Issue #5392: test stack overflow after hitting recursion
                  # limit twice
                  self.assertRaises(RecursionError, f)
                  self.assertRaises(RecursionError, f)
          finally:
              sys.setrecursionlimit(oldlimit)
  
      @test.support.cpython_only
      @unittest.skipUnderCinderJIT("Recursion limit not enforced: T87011403")
      def test_setrecursionlimit_recursion_depth(self):
          # Issue #25274: Setting a low recursion limit must be blocked if the
          # current recursion depth is already higher than the "lower-water
          # mark". Otherwise, it may not be possible anymore to
          # reset the overflowed flag to 0.
  
          from _testcapi import get_recursion_depth
  
          def set_recursion_limit_at_depth(depth, limit):
              recursion_depth = get_recursion_depth()
              if recursion_depth >= depth:
                  with self.assertRaises(RecursionError) as cm:
                      sys.setrecursionlimit(limit)
                  self.assertRegex(str(cm.exception),
                                   "cannot set the recursion limit to [0-9]+ "
                                   "at the recursion depth [0-9]+: "
                                   "the limit is too low")
              else:
                  set_recursion_limit_at_depth(depth, limit)
  
          oldlimit = sys.getrecursionlimit()
          try:
              sys.setrecursionlimit(1000)
  
              for limit in (10, 25, 50, 75, 100, 150, 200):
                  # formula extracted from _Py_RecursionLimitLowerWaterMark()
                  if limit > 200:
                      depth = limit - 50
                  else:
                      depth = limit * 3 // 4
                  set_recursion_limit_at_depth(depth, limit)
          finally:
              sys.setrecursionlimit(oldlimit)
  
      @unittest.skipIfDebug("Recursion overflows the C stack in debug")
      def test_recursionlimit_fatalerror(self):
          # A fatal error occurs if a second recursion limit is hit when recovering
          # from a first one.
          code = textwrap.dedent("""
              import sys
  
              def f():
                  try:
                      f()
                  except RecursionError:
                      f()
  
              sys.setrecursionlimit(%d)
              f()""")
          with test.support.SuppressCrashReport():
              for i in (50, 1000):
                  sub = subprocess.Popen([sys.executable, '-c', code % i],
                      stderr=subprocess.PIPE)
                  err = sub.communicate()[1]
                  self.assertTrue(sub.returncode, sub.returncode)
                  self.assertIn(
                      b"Fatal Python error: Cannot recover from stack overflow",
                      err)
  
      def test_getwindowsversion(self):
          # Raise SkipTest if sys doesn't have getwindowsversion attribute
          test.support.get_attribute(sys, "getwindowsversion")
          v = sys.getwindowsversion()
          self.assertEqual(len(v), 5)
          self.assertIsInstance(v[0], int)
          self.assertIsInstance(v[1], int)
          self.assertIsInstance(v[2], int)
          self.assertIsInstance(v[3], int)
          self.assertIsInstance(v[4], str)
          self.assertRaises(IndexError, operator.getitem, v, 5)
          self.assertIsInstance(v.major, int)
          self.assertIsInstance(v.minor, int)
          self.assertIsInstance(v.build, int)
          self.assertIsInstance(v.platform, int)
          self.assertIsInstance(v.service_pack, str)
          self.assertIsInstance(v.service_pack_minor, int)
          self.assertIsInstance(v.service_pack_major, int)
          self.assertIsInstance(v.suite_mask, int)
          self.assertIsInstance(v.product_type, int)
          self.assertEqual(v[0], v.major)
          self.assertEqual(v[1], v.minor)
          self.assertEqual(v[2], v.build)
          self.assertEqual(v[3], v.platform)
          self.assertEqual(v[4], v.service_pack)
  
          # This is how platform.py calls it. Make sure tuple
          #  still has 5 elements
          maj, min, buildno, plat, csd = sys.getwindowsversion()
  
      def test_call_tracing(self):
          self.assertRaises(TypeError, sys.call_tracing, type, 2)
  
      @unittest.skipUnless(hasattr(sys, "setdlopenflags"),
                           'test needs sys.setdlopenflags()')
      def test_dlopenflags(self):
          self.assertTrue(hasattr(sys, "getdlopenflags"))
          self.assertRaises(TypeError, sys.getdlopenflags, 42)
          oldflags = sys.getdlopenflags()
          self.assertRaises(TypeError, sys.setdlopenflags)
          sys.setdlopenflags(oldflags+1)
          self.assertEqual(sys.getdlopenflags(), oldflags+1)
          sys.setdlopenflags(oldflags)
  
      @test.support.refcount_test
      def test_refcount(self):
          # n here must be a global in order for this test to pass while
          # tracing with a python function.  Tracing calls PyFrame_FastToLocals
          # which will add a copy of any locals to the frame object, causing
          # the reference count to increase by 2 instead of 1.
          global n
          self.assertRaises(TypeError, sys.getrefcount)
          c = sys.getrefcount(None)
          n = None
          self.assertEqual(sys.getrefcount(None), c)
          del n
          self.assertEqual(sys.getrefcount(None), c)
          if hasattr(sys, "gettotalrefcount"):
              self.assertIsInstance(sys.gettotalrefcount(), int)
  
      def test_getframe(self):
          self.assertRaises(TypeError, sys._getframe, 42, 42)
          self.assertRaises(ValueError, sys._getframe, 2000000000)
          self.assertTrue(
              SysModuleTest.test_getframe.__code__ \
              is sys._getframe().f_code
          )
  
      # sys._current_frames() is a CPython-only gimmick.
      @test.support.reap_threads
      @unittest.skipUnderCinderJIT("Incorrect line numbers: T63031461")
      def test_current_frames(self):
          import threading
          import traceback
  
          # Spawn a thread that blocks at a known place.  Then the main
          # thread does sys._current_frames(), and verifies that the frames
          # returned make sense.
          entered_g = threading.Event()
          leave_g = threading.Event()
          thread_info = []  # the thread's id
  
          def f123():
              g456()
  
          def g456():
              thread_info.append(threading.get_ident())
              entered_g.set()
              leave_g.wait()
  
          t = threading.Thread(target=f123)
          t.start()
          entered_g.wait()
  
          # Make sure we signal t to end even if we exit early from a failed
          # assertion.
          try:
              # At this point, t has finished its entered_g.set(), although it's
              # impossible to guess whether it's still on that line or has moved
              # on to its leave_g.wait().
              self.assertEqual(len(thread_info), 1)
              thread_id = thread_info[0]
  
              d = sys._current_frames()
              for tid in d:
                  self.assertIsInstance(tid, int)
                  self.assertGreater(tid, 0)
  
              main_id = threading.get_ident()
              self.assertIn(main_id, d)
              self.assertIn(thread_id, d)
  
              # Verify that the captured main-thread frame is _this_ frame.
              frame = d.pop(main_id)
              self.assertTrue(frame is sys._getframe())
  
              # Verify that the captured thread frame is blocked in g456, called
              # from f123.  This is a litte tricky, since various bits of
              # threading.py are also in the thread's call stack.
              frame = d.pop(thread_id)
              stack = traceback.extract_stack(frame)
              for i, (filename, lineno, funcname, sourceline) in enumerate(stack):
                  if funcname == "f123":
                      break
              else:
                  self.fail("didn't find f123() on thread's call stack")
  
              self.assertEqual(sourceline, "g456()")
  
              # And the next record must be for g456().
              filename, lineno, funcname, sourceline = stack[i+1]
              self.assertEqual(funcname, "g456")
              self.assertIn(sourceline, ["leave_g.wait()", "entered_g.set()"])
          finally:
              # Reap the spawned thread.
              leave_g.set()
              t.join()
  
      def test_attributes(self):
          self.assertIsInstance(sys.api_version, int)
          self.assertIsInstance(sys.argv, list)
          self.assertIn(sys.byteorder, ("little", "big"))
          self.assertIsInstance(sys.builtin_module_names, tuple)
          self.assertIsInstance(sys.copyright, str)
          self.assertIsInstance(sys.exec_prefix, str)
          self.assertIsInstance(sys.base_exec_prefix, str)
          self.assertIsInstance(sys.executable, str)
          self.assertEqual(len(sys.float_info), 11)
          self.assertEqual(sys.float_info.radix, 2)
          self.assertEqual(len(sys.int_info), 2)
          self.assertTrue(sys.int_info.bits_per_digit % 5 == 0)
          self.assertTrue(sys.int_info.sizeof_digit >= 1)
          self.assertEqual(type(sys.int_info.bits_per_digit), int)
          self.assertEqual(type(sys.int_info.sizeof_digit), int)
          self.assertIsInstance(sys.hexversion, int)
  
          self.assertEqual(len(sys.hash_info), 9)
          self.assertLess(sys.hash_info.modulus, 2**sys.hash_info.width)
          # sys.hash_info.modulus should be a prime; we do a quick
          # probable primality test (doesn't exclude the possibility of
          # a Carmichael number)
          for x in range(1, 100):
              self.assertEqual(
                  pow(x, sys.hash_info.modulus-1, sys.hash_info.modulus),
                  1,
                  "sys.hash_info.modulus {} is a non-prime".format(
                      sys.hash_info.modulus)
                  )
          self.assertIsInstance(sys.hash_info.inf, int)
          self.assertIsInstance(sys.hash_info.nan, int)
          self.assertIsInstance(sys.hash_info.imag, int)
          algo = sysconfig.get_config_var("Py_HASH_ALGORITHM")
          if sys.hash_info.algorithm in {"fnv", "siphash24"}:
              self.assertIn(sys.hash_info.hash_bits, {32, 64})
              self.assertIn(sys.hash_info.seed_bits, {32, 64, 128})
  
              if algo == 1:
                  self.assertEqual(sys.hash_info.algorithm, "siphash24")
              elif algo == 2:
                  self.assertEqual(sys.hash_info.algorithm, "fnv")
              else:
                  self.assertIn(sys.hash_info.algorithm, {"fnv", "siphash24"})
          else:
              # PY_HASH_EXTERNAL
              self.assertEqual(algo, 0)
          self.assertGreaterEqual(sys.hash_info.cutoff, 0)
          self.assertLess(sys.hash_info.cutoff, 8)
  
          self.assertIsInstance(sys.maxsize, int)
          self.assertIsInstance(sys.maxunicode, int)
          self.assertEqual(sys.maxunicode, 0x10FFFF)
          self.assertIsInstance(sys.platform, str)
          self.assertIsInstance(sys.prefix, str)
          self.assertIsInstance(sys.base_prefix, str)
          self.assertIsInstance(sys.version, str)
          vi = sys.version_info
          self.assertIsInstance(vi[:], tuple)
          self.assertEqual(len(vi), 5)
          self.assertIsInstance(vi[0], int)
          self.assertIsInstance(vi[1], int)
          self.assertIsInstance(vi[2], int)
          self.assertIn(vi[3], ("alpha", "beta", "candidate", "final"))
          self.assertIsInstance(vi[4], int)
          self.assertIsInstance(vi.major, int)
          self.assertIsInstance(vi.minor, int)
          self.assertIsInstance(vi.micro, int)
          self.assertIn(vi.releaselevel, ("alpha", "beta", "candidate", "final"))
          self.assertIsInstance(vi.serial, int)
          self.assertEqual(vi[0], vi.major)
          self.assertEqual(vi[1], vi.minor)
          self.assertEqual(vi[2], vi.micro)
          self.assertEqual(vi[3], vi.releaselevel)
          self.assertEqual(vi[4], vi.serial)
          self.assertTrue(vi > (1,0,0))
          self.assertIsInstance(sys.float_repr_style, str)
          self.assertIn(sys.float_repr_style, ('short', 'legacy'))
          if not sys.platform.startswith('win'):
              self.assertIsInstance(sys.abiflags, str)
  
      def test_thread_info(self):
          info = sys.thread_info
          self.assertEqual(len(info), 3)
          self.assertIn(info.name, ('nt', 'pthread', 'solaris', None))
          self.assertIn(info.lock, ('semaphore', 'mutex+cond', None))
  
      def test_43581(self):
          # Can't use sys.stdout, as this is a StringIO object when
          # the test runs under regrtest.
          self.assertEqual(sys.__stdout__.encoding, sys.__stderr__.encoding)
  
      def test_intern(self):
          global INTERN_NUMRUNS
          INTERN_NUMRUNS += 1
          self.assertRaises(TypeError, sys.intern)
          s = "never interned before" + str(INTERN_NUMRUNS)
          self.assertTrue(sys.intern(s) is s)
          s2 = s.swapcase().swapcase()
          self.assertTrue(sys.intern(s2) is s)
  
          # Subclasses of string can't be interned, because they
          # provide too much opportunity for insane things to happen.
          # We don't want them in the interned dict and if they aren't
          # actually interned, we don't want to create the appearance
          # that they are by allowing intern() to succeed.
          class S(str):
              def __hash__(self):
                  return 123
  
          self.assertRaises(TypeError, sys.intern, S("abc"))
  
      def test_sys_flags(self):
          self.assertTrue(sys.flags)
          attrs = ("debug",
                   "inspect", "interactive", "optimize", "dont_write_bytecode",
                   "no_user_site", "no_site", "ignore_environment", "verbose",
                   "bytes_warning", "quiet", "hash_randomization", "isolated",
                   "dev_mode", "utf8_mode")
          for attr in attrs:
              self.assertTrue(hasattr(sys.flags, attr), attr)
              attr_type = bool if attr == "dev_mode" else int
              self.assertEqual(type(getattr(sys.flags, attr)), attr_type, attr)
          self.assertTrue(repr(sys.flags))
          self.assertEqual(len(sys.flags), len(attrs))
  
          self.assertIn(sys.flags.utf8_mode, {0, 1, 2})
  
      def assert_raise_on_new_sys_type(self, sys_attr):
          # Users are intentionally prevented from creating new instances of
          # sys.flags, sys.version_info, and sys.getwindowsversion.
          attr_type = type(sys_attr)
          with self.assertRaises(TypeError):
              attr_type()
          with self.assertRaises(TypeError):
              attr_type.__new__(attr_type)
  
      def test_sys_flags_no_instantiation(self):
          self.assert_raise_on_new_sys_type(sys.flags)
  
      def test_sys_version_info_no_instantiation(self):
          self.assert_raise_on_new_sys_type(sys.version_info)
  
      def test_sys_getwindowsversion_no_instantiation(self):
          # Skip if not being run on Windows.
          test.support.get_attribute(sys, "getwindowsversion")
          self.assert_raise_on_new_sys_type(sys.getwindowsversion())
  
      @test.support.cpython_only
      def test_clear_type_cache(self):
          sys._clear_type_cache()
  
      def test_ioencoding(self):
          env = dict(os.environ)
  
          # Test character: cent sign, encoded as 0x4A (ASCII J) in CP424,
          # not representable in ASCII.
  
          env["PYTHONIOENCODING"] = "cp424"
          p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
                               stdout = subprocess.PIPE, env=env)
          out = p.communicate()[0].strip()
          expected = ("\xa2" + os.linesep).encode("cp424")
          self.assertEqual(out, expected)
  
          env["PYTHONIOENCODING"] = "ascii:replace"
          p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
                               stdout = subprocess.PIPE, env=env)
          out = p.communicate()[0].strip()
          self.assertEqual(out, b'?')
  
          env["PYTHONIOENCODING"] = "ascii"
          p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
                               stdout=subprocess.PIPE, stderr=subprocess.PIPE,
                               env=env)
          out, err = p.communicate()
          self.assertEqual(out, b'')
          self.assertIn(b'UnicodeEncodeError:', err)
          self.assertIn(rb"'\xa2'", err)
  
          env["PYTHONIOENCODING"] = "ascii:"
          p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'],
                               stdout=subprocess.PIPE, stderr=subprocess.PIPE,
                               env=env)
          out, err = p.communicate()
          self.assertEqual(out, b'')
          self.assertIn(b'UnicodeEncodeError:', err)
          self.assertIn(rb"'\xa2'", err)
  
          env["PYTHONIOENCODING"] = ":surrogateescape"
          p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xdcbd))'],
                               stdout=subprocess.PIPE, env=env)
          out = p.communicate()[0].strip()
          self.assertEqual(out, b'\xbd')
  
      @unittest.skipUnless(test.support.FS_NONASCII,
                           'requires OS support of non-ASCII encodings')
      @unittest.skipUnless(sys.getfilesystemencoding() == locale.getpreferredencoding(False),
                           'requires FS encoding to match locale')
      def test_ioencoding_nonascii(self):
          env = dict(os.environ)
  
          env["PYTHONIOENCODING"] = ""
          p = subprocess.Popen([sys.executable, "-c",
                                  'print(%a)' % test.support.FS_NONASCII],
                                  stdout=subprocess.PIPE, env=env)
          out = p.communicate()[0].strip()
          self.assertEqual(out, os.fsencode(test.support.FS_NONASCII))
  
      @unittest.skipIf(sys.base_prefix != sys.prefix,
                       'Test is not venv-compatible')
      def test_executable(self):
          # sys.executable should be absolute
          self.assertEqual(os.path.abspath(sys.executable), sys.executable)
  
          # Issue #7774: Ensure that sys.executable is an empty string if argv[0]
          # has been set to a non existent program name and Python is unable to
          # retrieve the real program name
  
          # For a normal installation, it should work without 'cwd'
          # argument. For test runs in the build directory, see #7774.
          python_dir = os.path.dirname(os.path.realpath(sys.executable))
          p = subprocess.Popen(
              ["nonexistent", "-c",
               'import sys; print(sys.executable.encode("ascii", "backslashreplace"))'],
              executable=sys.executable, stdout=subprocess.PIPE, cwd=python_dir)
          stdout = p.communicate()[0]
          executable = stdout.strip().decode("ASCII")
          p.wait()
          self.assertIn(executable, ["b''", repr(sys.executable.encode("ascii", "backslashreplace"))])
  
      def check_fsencoding(self, fs_encoding, expected=None):
          self.assertIsNotNone(fs_encoding)
          codecs.lookup(fs_encoding)
          if expected:
              self.assertEqual(fs_encoding, expected)
  
      def test_getfilesystemencoding(self):
          fs_encoding = sys.getfilesystemencoding()
          if sys.platform == 'darwin':
              expected = 'utf-8'
          else:
              expected = None
          self.check_fsencoding(fs_encoding, expected)
  
      def c_locale_get_error_handler(self, locale, isolated=False, encoding=None):
          # Force the POSIX locale
          env = os.environ.copy()
          env["LC_ALL"] = locale
          env["PYTHONCOERCECLOCALE"] = "0"
          code = '\n'.join((
              'import sys',
              'def dump(name):',
              '    std = getattr(sys, name)',
              '    print("%s: %s" % (name, std.errors))',
              'dump("stdin")',
              'dump("stdout")',
              'dump("stderr")',
          ))
          args = [sys.executable, "-X", "utf8=0", "-c", code]
          if isolated:
              args.append("-I")
          if encoding is not None:
              env['PYTHONIOENCODING'] = encoding
          else:
              env.pop('PYTHONIOENCODING', None)
          p = subprocess.Popen(args,
                                stdout=subprocess.PIPE,
                                stderr=subprocess.STDOUT,
                                env=env,
                                universal_newlines=True)
          stdout, stderr = p.communicate()
          return stdout
  
      def check_locale_surrogateescape(self, locale):
          out = self.c_locale_get_error_handler(locale, isolated=True)
          self.assertEqual(out,
                           'stdin: surrogateescape\n'
                           'stdout: surrogateescape\n'
                           'stderr: backslashreplace\n')
  
          # replace the default error handler
          out = self.c_locale_get_error_handler(locale, encoding=':ignore')
          self.assertEqual(out,
                           'stdin: ignore\n'
                           'stdout: ignore\n'
                           'stderr: backslashreplace\n')
  
          # force the encoding
          out = self.c_locale_get_error_handler(locale, encoding='iso8859-1')
          self.assertEqual(out,
                           'stdin: strict\n'
                           'stdout: strict\n'
                           'stderr: backslashreplace\n')
          out = self.c_locale_get_error_handler(locale, encoding='iso8859-1:')
          self.assertEqual(out,
                           'stdin: strict\n'
                           'stdout: strict\n'
                           'stderr: backslashreplace\n')
  
          # have no any effect
          out = self.c_locale_get_error_handler(locale, encoding=':')
          self.assertEqual(out,
                           'stdin: surrogateescape\n'
                           'stdout: surrogateescape\n'
                           'stderr: backslashreplace\n')
          out = self.c_locale_get_error_handler(locale, encoding='')
          self.assertEqual(out,
                           'stdin: surrogateescape\n'
                           'stdout: surrogateescape\n'
                           'stderr: backslashreplace\n')
  
      def test_c_locale_surrogateescape(self):
          self.check_locale_surrogateescape('C')
  
      def test_posix_locale_surrogateescape(self):
          self.check_locale_surrogateescape('POSIX')
  
      def test_implementation(self):
          # This test applies to all implementations equally.
  
          levels = {'alpha': 0xA, 'beta': 0xB, 'candidate': 0xC, 'final': 0xF}
  
          self.assertTrue(hasattr(sys.implementation, 'name'))
          self.assertTrue(hasattr(sys.implementation, 'version'))
          self.assertTrue(hasattr(sys.implementation, 'hexversion'))
          self.assertTrue(hasattr(sys.implementation, 'cache_tag'))
  
          version = sys.implementation.version
          self.assertEqual(version[:2], (version.major, version.minor))
  
          hexversion = (version.major << 24 | version.minor << 16 |
                        version.micro << 8 | levels[version.releaselevel] << 4 |
                        version.serial << 0)
          self.assertEqual(sys.implementation.hexversion, hexversion)
  
          # PEP 421 requires that .name be lower case.
          self.assertEqual(sys.implementation.name,
                           sys.implementation.name.lower())
  
      def test_cinder_implementation(self):
          self.assertTrue(hasattr(sys.implementation, '_is_cinder'))
          self.assertEqual(sys.implementation._is_cinder, True)
  
      @test.support.cpython_only
      def test_debugmallocstats(self):
          # Test sys._debugmallocstats()
          from test.support.script_helper import assert_python_ok
          args = ['-c', 'import sys; sys._debugmallocstats()']
          ret, out, err = assert_python_ok(*args)
          self.assertIn(b"free PyDictObjects", err)
  
          # The function has no parameter
          self.assertRaises(TypeError, sys._debugmallocstats, True)
  
      @unittest.skipUnless(hasattr(sys, "getallocatedblocks"),
                           "sys.getallocatedblocks unavailable on this build")
      def test_getallocatedblocks(self):
          try:
              import _testcapi
          except ImportError:
              with_pymalloc = support.with_pymalloc()
          else:
              try:
                  alloc_name = _testcapi.pymem_getallocatorsname()
              except RuntimeError as exc:
                  # "cannot get allocators name" (ex: tracemalloc is used)
                  with_pymalloc = True
              else:
                  with_pymalloc = (alloc_name in ('pymalloc', 'pymalloc_debug'))
  
          # Some sanity checks
          a = sys.getallocatedblocks()
          self.assertIs(type(a), int)
          if with_pymalloc:
              self.assertGreater(a, 0)
          else:
              # When WITH_PYMALLOC isn't available, we don't know anything
              # about the underlying implementation: the function might
              # return 0 or something greater.
              self.assertGreaterEqual(a, 0)
          try:
              # While we could imagine a Python session where the number of
              # multiple buffer objects would exceed the sharing of references,
              # it is unlikely to happen in a normal test run.
              self.assertLess(a, sys.gettotalrefcount())
          except AttributeError:
              # gettotalrefcount() not available
              pass
          gc.collect()
          b = sys.getallocatedblocks()
          self.assertLessEqual(b, a)
          gc.collect()
          c = sys.getallocatedblocks()
          self.assertIn(c, range(b - 50, b + 50))
  
      @test.support.requires_type_collecting
      def test_is_finalizing(self):
          self.assertIs(sys.is_finalizing(), False)
          # Don't use the atexit module because _Py_Finalizing is only set
          # after calling atexit callbacks
          code = """if 1:
              import sys
  
              class AtExit:
                  is_finalizing = sys.is_finalizing
                  print = print
  
                  def __del__(self):
                      self.print(self.is_finalizing(), flush=True)
  
              # Keep a reference in the __main__ module namespace, so the
              # AtExit destructor will be called at Python exit
              ref = AtExit()
          """
          rc, stdout, stderr = assert_python_ok('-c', code)
          self.assertEqual(stdout.rstrip(), b'True')
  
      @test.support.requires_type_collecting
      def test_issue20602(self):
          # sys.flags and sys.float_info were wiped during shutdown.
          code = """if 1:
              import sys
              class A:
                  def __del__(self, sys=sys):
                      print(sys.flags)
                      print(sys.float_info)
              a = A()
              """
          rc, out, err = assert_python_ok('-c', code)
          out = out.splitlines()
          self.assertIn(b'sys.flags', out[0])
          self.assertIn(b'sys.float_info', out[1])
  
      @unittest.skipUnless(hasattr(sys, 'getandroidapilevel'),
                           'need sys.getandroidapilevel()')
      def test_getandroidapilevel(self):
          level = sys.getandroidapilevel()
          self.assertIsInstance(level, int)
          self.assertGreater(level, 0)
  
      def test_sys_tracebacklimit(self):
          code = """if 1:
              import sys
              def f1():
                  1 / 0
              def f2():
                  f1()
              sys.tracebacklimit = %r
              f2()
          """
          def check(tracebacklimit, expected):
              p = subprocess.Popen([sys.executable, '-c', code % tracebacklimit],
                                   stderr=subprocess.PIPE)
              out = p.communicate()[1]
              self.assertEqual(out.splitlines(), expected)
  
          traceback = [
              b'Traceback (most recent call last):',
              b'  File "<string>", line 8, in <module>',
              b'  File "<string>", line 6, in f2',
              b'  File "<string>", line 4, in f1',
              b'ZeroDivisionError: division by zero'
          ]
          check(10, traceback)
          check(3, traceback)
          check(2, traceback[:1] + traceback[2:])
          check(1, traceback[:1] + traceback[3:])
          check(0, [traceback[-1]])
          check(-1, [traceback[-1]])
          check(1<<1000, traceback)
          check(-1<<1000, [traceback[-1]])
          check(None, traceback)
  
      def test_no_duplicates_in_meta_path(self):
          self.assertEqual(len(sys.meta_path), len(set(sys.meta_path)))
  
      @unittest.skipUnless(hasattr(sys, "_enablelegacywindowsfsencoding"),
                           'needs sys._enablelegacywindowsfsencoding()')
      def test__enablelegacywindowsfsencoding(self):
          code = ('import sys',
                  'sys._enablelegacywindowsfsencoding()',
                  'print(sys.getfilesystemencoding(), sys.getfilesystemencodeerrors())')
          rc, out, err = assert_python_ok('-c', '; '.join(code))
          out = out.decode('ascii', 'replace').rstrip()
          self.assertEqual(out, 'mbcs replace')
  
  
  @test.support.cpython_only
  class UnraisableHookTest(unittest.TestCase):
      def write_unraisable_exc(self, exc, err_msg, obj):
          import _testcapi
          import types
          err_msg2 = f"Exception ignored {err_msg}"
          try:
              _testcapi.write_unraisable_exc(exc, err_msg, obj)
              return types.SimpleNamespace(exc_type=type(exc),
                                           exc_value=exc,
                                           exc_traceback=exc.__traceback__,
                                           err_msg=err_msg2,
                                           object=obj)
          finally:
              # Explicitly break any reference cycle
              exc = None
  
      def test_original_unraisablehook(self):
          for err_msg in (None, "original hook"):
              with self.subTest(err_msg=err_msg):
                  obj = "an object"
  
                  with test.support.captured_output("stderr") as stderr:
                      with test.support.swap_attr(sys, 'unraisablehook',
                                                  sys.__unraisablehook__):
                          self.write_unraisable_exc(ValueError(42), err_msg, obj)
  
                  err = stderr.getvalue()
                  if err_msg is not None:
                      self.assertIn(f'Exception ignored {err_msg}: {obj!r}\n', err)
                  else:
                      self.assertIn(f'Exception ignored in: {obj!r}\n', err)
                  self.assertIn('Traceback (most recent call last):\n', err)
                  self.assertIn('ValueError: 42\n', err)
  
      def test_original_unraisablehook_err(self):
          # bpo-22836: PyErr_WriteUnraisable() should give sensible reports
          class BrokenDel:
              def __del__(self):
                  exc = ValueError("del is broken")
                  # The following line is included in the traceback report:
                  raise exc
  
          class BrokenStrException(Exception):
              def __str__(self):
                  raise Exception("str() is broken")
  
          class BrokenExceptionDel:
              def __del__(self):
                  exc = BrokenStrException()
                  # The following line is included in the traceback report:
                  raise exc
  
          for test_class in (BrokenDel, BrokenExceptionDel):
              with self.subTest(test_class):
                  obj = test_class()
                  with test.support.captured_stderr() as stderr, \
                       test.support.swap_attr(sys, 'unraisablehook',
                                              sys.__unraisablehook__):
                      # Trigger obj.__del__()
                      del obj
  
                  report = stderr.getvalue()
                  self.assertIn("Exception ignored", report)
                  self.assertIn(test_class.__del__.__qualname__, report)
                  self.assertIn("test_sys.py", report)
                  self.assertIn("raise exc", report)
                  if test_class is BrokenExceptionDel:
                      self.assertIn("BrokenStrException", report)
                      self.assertIn("<exception str() failed>", report)
                  else:
                      self.assertIn("ValueError", report)
                      self.assertIn("del is broken", report)
                  self.assertTrue(report.endswith("\n"))
  
  
      def test_original_unraisablehook_wrong_type(self):
          exc = ValueError(42)
          with test.support.swap_attr(sys, 'unraisablehook',
                                      sys.__unraisablehook__):
              with self.assertRaises(TypeError):
                  sys.unraisablehook(exc)
  
      def test_custom_unraisablehook(self):
          hook_args = None
  
          def hook_func(args):
              nonlocal hook_args
              hook_args = args
  
          obj = object()
          try:
              with test.support.swap_attr(sys, 'unraisablehook', hook_func):
                  expected = self.write_unraisable_exc(ValueError(42),
                                                       "custom hook", obj)
                  for attr in "exc_type exc_value exc_traceback err_msg object".split():
                      self.assertEqual(getattr(hook_args, attr),
                                       getattr(expected, attr),
                                       (hook_args, expected))
          finally:
              # expected and hook_args contain an exception: break reference cycle
              expected = None
              hook_args = None
  
      def test_custom_unraisablehook_fail(self):
          def hook_func(*args):
              raise Exception("hook_func failed")
  
          with test.support.captured_output("stderr") as stderr:
              with test.support.swap_attr(sys, 'unraisablehook', hook_func):
                  self.write_unraisable_exc(ValueError(42),
                                            "custom hook fail", None)
  
          err = stderr.getvalue()
          self.assertIn(f'Exception ignored in sys.unraisablehook: '
                        f'{hook_func!r}\n',
                        err)
          self.assertIn('Traceback (most recent call last):\n', err)
          self.assertIn('Exception: hook_func failed\n', err)
  
  
  @test.support.cpython_only
  class SizeofTest(unittest.TestCase):
  
      def setUp(self):
          self.P = struct.calcsize('P')
          self.longdigit = sys.int_info.sizeof_digit
          import _testcapi
          self.gc_headsize = _testcapi.SIZEOF_PYGC_HEAD
  
      check_sizeof = test.support.check_sizeof
  
      def test_gc_head_size(self):
          # Check that the gc header size is added to objects tracked by the gc.
          vsize = test.support.calcvobjsize
          gc_header_size = self.gc_headsize
          # bool objects are not gc tracked
          self.assertEqual(sys.getsizeof(True), vsize('') + self.longdigit)
          # but lists are
          self.assertEqual(sys.getsizeof([]), vsize('Pn') + gc_header_size)
  
      def test_errors(self):
          class BadSizeof:
              def __sizeof__(self):
                  raise ValueError
          self.assertRaises(ValueError, sys.getsizeof, BadSizeof())
  
          class InvalidSizeof:
              def __sizeof__(self):
                  return None
          self.assertRaises(TypeError, sys.getsizeof, InvalidSizeof())
          sentinel = ["sentinel"]
          self.assertIs(sys.getsizeof(InvalidSizeof(), sentinel), sentinel)
  
          class FloatSizeof:
              def __sizeof__(self):
                  return 4.5
          self.assertRaises(TypeError, sys.getsizeof, FloatSizeof())
          self.assertIs(sys.getsizeof(FloatSizeof(), sentinel), sentinel)
  
          class OverflowSizeof(int):
              def __sizeof__(self):
                  return int(self)
          self.assertEqual(sys.getsizeof(OverflowSizeof(sys.maxsize)),
                           sys.maxsize + self.gc_headsize)
          with self.assertRaises(OverflowError):
              sys.getsizeof(OverflowSizeof(sys.maxsize + 1))
          with self.assertRaises(ValueError):
              sys.getsizeof(OverflowSizeof(-1))
          with self.assertRaises((ValueError, OverflowError)):
              sys.getsizeof(OverflowSizeof(-sys.maxsize - 1))
  
      def test_default(self):
          size = test.support.calcvobjsize
          self.assertEqual(sys.getsizeof(True), size('') + self.longdigit)
          self.assertEqual(sys.getsizeof(True, -1), size('') + self.longdigit)
  
      def test_objecttypes(self):
          # check all types defined in Objects/
          calcsize = struct.calcsize
          size = test.support.calcobjsize
          vsize = test.support.calcvobjsize
          check = self.check_sizeof
          # bool
          check(True, vsize('') + self.longdigit)
          # buffer
          # XXX
          # builtin_function_or_method
          check(len, size('5P'))
          # bytearray
          samples = [b'', b'u'*100000]
          for sample in samples:
              x = bytearray(sample)
              check(x, vsize('n2Pi') + x.__alloc__())
          # bytearray_iterator
          check(iter(bytearray()), size('nP'))
          # bytes
          check(b'', vsize('n') + 1)
          check(b'x' * 10, vsize('n') + 11)
          # cell
          def get_cell():
              x = 42
              def inner():
                  return x
              return inner
          check(get_cell().__closure__[0], size('P'))
          # code
          def check_code_size(a, expected_size):
              self.assertGreaterEqual(sys.getsizeof(a), expected_size)
          check_code_size(get_cell().__code__, size('6i13P'))
          check_code_size(get_cell.__code__, size('6i13P'))
          def get_cell2(x):
              def inner():
                  return x
              return inner
          check_code_size(get_cell2.__code__, size('6i13P') + calcsize('n'))
          # complex
          check(complex(0,1), size('2d'))
          # method_descriptor (descriptor object)
          check(str.lower, size('3PPP'))
          # classmethod_descriptor (descriptor object)
          # XXX
          # member_descriptor (descriptor object)
          import datetime
          check(datetime.timedelta.days, size('3PP'))
          # getset_descriptor (descriptor object)
          import collections
          check(collections.defaultdict.default_factory, size('3PP'))
          # wrapper_descriptor (descriptor object)
          check(int.__add__, size('3P3P'))
          # method-wrapper (descriptor object)
          check({}.__iter__, size('3P'))
          # empty dict
          check({}, size('nQ2P'))
          # dict
          check({"a": 1}, size('nQ2P') + calcsize('2nP2n') + 8 + (8*2//3)*calcsize('n2P'))
          longdict = {1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8}
          check(longdict, size('nQ2P') + calcsize('2nP2n') + 16 + (16*2//3)*calcsize('n2P'))
          # dictionary-keyview
          check({}.keys(), size('P'))
          # dictionary-valueview
          check({}.values(), size('P'))
          # dictionary-itemview
          check({}.items(), size('P'))
          # dictionary iterator
          check(iter({}), size('P2nPn'))
          # dictionary-keyiterator
          check(iter({}.keys()), size('P2nPn'))
          # dictionary-valueiterator
          check(iter({}.values()), size('P2nPn'))
          # dictionary-itemiterator
          check(iter({}.items()), size('P2nPn'))
          # dictproxy
          class C(object): pass
          check(C.__dict__, size('P'))
          # BaseException
          check(BaseException(), size('5Pb'))
          # UnicodeEncodeError
          check(UnicodeEncodeError("", "", 0, 0, ""), size('5Pb 2P2nP'))
          # UnicodeDecodeError
          check(UnicodeDecodeError("", b"", 0, 0, ""), size('5Pb 2P2nP'))
          # UnicodeTranslateError
          check(UnicodeTranslateError("", 0, 1, ""), size('5Pb 2P2nP'))
          # ellipses
          check(Ellipsis, size(''))
          # EncodingMap
          import codecs, encodings.iso8859_3
          x = codecs.charmap_build(encodings.iso8859_3.decoding_table)
          check(x, size('32B2iB'))
          # enumerate
          check(enumerate([]), size('n3P'))
          # reverse
          check(reversed(''), size('nP'))
          # float
          check(float(0), size('d'))
          # sys.floatinfo
          check(sys.float_info, vsize('') + self.P * len(sys.float_info))
          # frame
          import inspect
          CO_MAXBLOCKS = 20
          x = inspect.currentframe()
          ncells = len(x.f_code.co_cellvars)
          nfrees = len(x.f_code.co_freevars)
          extras = x.f_code.co_stacksize + x.f_code.co_nlocals +\
                    ncells + nfrees - 1
          check(x, vsize('5P2c4P3ic' + CO_MAXBLOCKS*'3i' + 'P' + extras*'P'))
          # function
          def func(): pass
          check(func, size('13P'))
          class c():
              @staticmethod
              def foo():
                  pass
              @classmethod
              def bar(cls):
                  pass
              # staticmethod
              check(foo, size('PP'))
              # classmethod
              check(bar, size('PP'))
          # generator
          def get_gen(): yield 1
          check(get_gen(), size('Pb2PPP4PP'))
          # iterator
          check(iter('abc'), size('lP'))
          # callable-iterator
          import re
          check(re.finditer('',''), size('2P'))
          # list
          samples = [[], [1,2,3], ['1', '2', '3']]
          for sample in samples:
              check(sample, vsize('Pn') + len(sample)*self.P)
          # sortwrapper (list)
          # XXX
          # cmpwrapper (list)
          # XXX
          # listiterator (list)
          check(iter([]), size('lP'))
          # listreverseiterator (list)
          check(reversed([]), size('nP'))
          # int
          check(0, vsize(''))
          check(1, vsize('') + self.longdigit)
          check(-1, vsize('') + self.longdigit)
          PyLong_BASE = 2**sys.int_info.bits_per_digit
          check(int(PyLong_BASE), vsize('') + 2*self.longdigit)
          check(int(PyLong_BASE**2-1), vsize('') + 2*self.longdigit)
          check(int(PyLong_BASE**2), vsize('') + 3*self.longdigit)
          # module
          check(unittest, size('PnPPP'))
          # None
          check(None, size(''))
          # NotImplementedType
          check(NotImplemented, size(''))
          # object
          check(object(), size(''))
          # property (descriptor object)
          class C(object):
              def getx(self): return self.__x
              def setx(self, value): self.__x = value
              def delx(self): del self.__x
              x = property(getx, setx, delx, "")
              check(x, size('4Pi'))
          # PyCapsule
          # XXX
          # rangeiterator
          check(iter(range(1)), size('4l'))
          # reverse
          check(reversed(''), size('nP'))
          # range
          check(range(1), size('4P'))
          check(range(66000), size('4P'))
          # set
          # frozenset
          PySet_MINSIZE = 8
          samples = [[], range(10), range(50)]
          s = size('3nP' + PySet_MINSIZE*'nP' + '2nP')
          for sample in samples:
              minused = len(sample)
              if minused == 0: tmp = 1
              # the computation of minused is actually a bit more complicated
              # but this suffices for the sizeof test
              minused = minused*2
              newsize = PySet_MINSIZE
              while newsize <= minused:
                  newsize = newsize << 1
              if newsize <= 8:
                  check(set(sample), s)
                  check(frozenset(sample), s)
              else:
                  check(set(sample), s + newsize*calcsize('nP'))
                  check(frozenset(sample), s + newsize*calcsize('nP'))
          # setiterator
          check(iter(set()), size('P3n'))
          # slice
          check(slice(0), size('3P'))
          # super
          check(super(int), size('3P'))
          # tuple
          check((), vsize(''))
          check((1,2,3), vsize('') + 3*self.P)
          # type
          # static type: PyTypeObject
          fmt = 'P2nPI13Pl4Pn9Pn11PIPPP'
          if hasattr(sys, 'getcounts'):
              fmt += '3n2P'
          s = vsize(fmt)
          check(int, s)
          # class
          s = vsize(fmt +                 # PyTypeObject
                    '3P'                  # PyAsyncMethods
                    '36P'                 # PyNumberMethods
                    '3P'                  # PyMappingMethods
                    '10P'                 # PySequenceMethods
                    '2P'                  # PyBufferProcs
                    '4P')
          class newstyleclass(object): pass
          # Separate block for PyDictKeysObject with 8 keys and 5 entries
          check(newstyleclass, s + calcsize("2nP2n0P") + 8 + 5*calcsize("n2P"))
          # dict with shared keys
          check(newstyleclass().__dict__, size('nQ2P') + 5*self.P)
          o = newstyleclass()
          o.a = o.b = o.c = o.d = o.e = o.f = o.g = o.h = 1
          # Separate block for PyDictKeysObject with 16 keys and 10 entries
          check(newstyleclass, s + calcsize("2nP2n0P") + 16 + 10*calcsize("n2P"))
          # dict with shared keys
          check(newstyleclass().__dict__, size('nQ2P') + 10*self.P)
          # unicode
          # each tuple contains a string and its expected character size
          # don't put any static strings here, as they may contain
          # wchar_t or UTF-8 representations
          samples = ['1'*100, '\xff'*50,
                     '\u0100'*40, '\uffff'*100,
                     '\U00010000'*30, '\U0010ffff'*100]
          asciifields = "nnbP"
          compactfields = asciifields + "nPn"
          unicodefields = compactfields + "P"
          for s in samples:
              maxchar = ord(max(s))
              if maxchar < 128:
                  L = size(asciifields) + len(s) + 1
              elif maxchar < 256:
                  L = size(compactfields) + len(s) + 1
              elif maxchar < 65536:
                  L = size(compactfields) + 2*(len(s) + 1)
              else:
                  L = size(compactfields) + 4*(len(s) + 1)
              check(s, L)
          # verify that the UTF-8 size is accounted for
          s = chr(0x4000)   # 4 bytes canonical representation
          check(s, size(compactfields) + 4)
          # compile() will trigger the generation of the UTF-8
          # representation as a side effect
          compile(s, "<stdin>", "eval")
          check(s, size(compactfields) + 4 + 4)
          # TODO: add check that forces the presence of wchar_t representation
          # TODO: add check that forces layout of unicodefields
          # weakref
          import weakref
          check(weakref.ref(int), size('2Pn3P'))
          # weakproxy
          # XXX
          # weakcallableproxy
          check(weakref.proxy(int), size('2Pn3P'))
  
      def check_slots(self, obj, base, extra):
          expected = sys.getsizeof(base) + struct.calcsize(extra)
          if gc.is_tracked(obj) and not gc.is_tracked(base):
              expected += self.gc_headsize
          self.assertEqual(sys.getsizeof(obj), expected)
  
      def test_slots(self):
          # check all subclassable types defined in Objects/ that allow
          # non-empty __slots__
          check = self.check_slots
          class BA(bytearray):
              __slots__ = 'a', 'b', 'c'
          check(BA(), bytearray(), '3P')
          class D(dict):
              __slots__ = 'a', 'b', 'c'
          check(D(x=[]), {'x': []}, '3P')
          class L(list):
              __slots__ = 'a', 'b', 'c'
          check(L(), [], '3P')
          class S(set):
              __slots__ = 'a', 'b', 'c'
          check(S(), set(), '3P')
          class FS(frozenset):
              __slots__ = 'a', 'b', 'c'
          check(FS(), frozenset(), '3P')
          from collections import OrderedDict
          class OD(OrderedDict):
              __slots__ = 'a', 'b', 'c'
          check(OD(x=[]), OrderedDict(x=[]), '3P')
  
      def test_pythontypes(self):
          # check all types defined in Python/
          size = test.support.calcobjsize
          vsize = test.support.calcvobjsize
          check = self.check_sizeof
          # _ast.AST
          import _ast
          check(_ast.AST(), size('PP'))
          try:
              raise TypeError
          except TypeError:
              tb = sys.exc_info()[2]
              # traceback
              if tb is not None:
                  check(tb, size('2P2i'))
          # symtable entry
          # XXX
          # sys.flags
          check(sys.flags, vsize('') + self.P * len(sys.flags))
  
      def test_asyncgen_hooks(self):
          old = sys.get_asyncgen_hooks()
          self.assertIsNone(old.firstiter)
          self.assertIsNone(old.finalizer)
  
          firstiter = lambda *a: None
          sys.set_asyncgen_hooks(firstiter=firstiter)
          hooks = sys.get_asyncgen_hooks()
          self.assertIs(hooks.firstiter, firstiter)
          self.assertIs(hooks[0], firstiter)
          self.assertIs(hooks.finalizer, None)
          self.assertIs(hooks[1], None)
  
          finalizer = lambda *a: None
          sys.set_asyncgen_hooks(finalizer=finalizer)
          hooks = sys.get_asyncgen_hooks()
          self.assertIs(hooks.firstiter, firstiter)
          self.assertIs(hooks[0], firstiter)
          self.assertIs(hooks.finalizer, finalizer)
          self.assertIs(hooks[1], finalizer)
  
          sys.set_asyncgen_hooks(*old)
          cur = sys.get_asyncgen_hooks()
          self.assertIsNone(cur.firstiter)
          self.assertIsNone(cur.finalizer)
  
      def test_method_free_list(self):
          # test default initial size
          self.assertEqual(256, sys._get_method_free_list_size())
  
          # disable the cache
          sys._set_method_free_list_size(0)
          self.assertEqual(0, sys._get_method_free_list_size())
  
          # invalid values
          self.assertRaises(OverflowError, sys._set_method_free_list_size, -1)
          self.assertRaises(TypeError, sys._set_method_free_list_size, None)
  
          # raise the size
          sys._set_method_free_list_size(512)
          self.assertEqual(512, sys._get_method_free_list_size())
  
          stats = sys._get_method_free_list_stats()
          has_stats = stats[1] != -1
  
          # Could be broken if the test framework changes to use more methods
          self.assertEqual(1, stats[0])
          class C:
              def f(self): pass
  
          fill_cache = [C().f for i in range(600)]
          self.assertEqual(1, stats[0])
          del fill_cache
          # cache is now fully populated
  
          stats = sys._get_method_free_list_stats()
          self.assertEqual(512, stats[0])
  
          # reduce size
          sys._set_method_free_list_size(256)
          self.assertEqual(256, sys._get_method_free_list_size())
          if has_stats:
              size, hits, misses = sys._get_method_free_list_stats()
              C().f
              size2, hits2, misses2 = sys._get_method_free_list_stats()
              # cache hits are tracked
              self.assertEqual(hits + 1, hits2)
  
              [C().f for i in range(size2 + 1)]
              size3, hits3, misses3 = sys._get_method_free_list_stats()
              # cache misses are tracked
              self.assertEqual(misses2 + 1, misses3)
  
      @unittest.skipUnderCinderJIT(
          "Assumes implementation details of a non-JIT method cache")
      def test_get_method_cache_stats(self):
          if sysconfig.get_config_var('Py_DEBUG') == 0:
              return
          cache_stats = sys._get_method_cache_stats()
  
          self.assertIs(type(cache_stats), dict)
  
          self.assertIn("num_hits", cache_stats)
          self.assertIn("num_misses", cache_stats)
          self.assertIn("num_collisions", cache_stats)
  
          sys._reset_method_cache_stats()
  
          class Foo:
              bar = 'testing 123'
  
          prev = sys._get_method_cache_stats()
  
          # Should be a cache miss
          for i in range(20):
              getattr(Foo, 'baz' + str(i), None)
  
          # Second access should be a cache hit
          Foo.bar
          Foo.bar
  
          curr = sys._get_method_cache_stats()
          self.assertGreater(curr['num_hits'], prev['num_hits'])
          self.assertGreater(curr['num_misses'], prev['num_misses'])
  
  if __name__ == "__main__":
      unittest.main()
  