# -*- coding: iso-8859-1 -*- import unittest, test.support import sys, io, os import struct import subprocess import textwrap # count the number of test runs, used to create unique # strings to intern in test_intern() numruns = 0 class SysModuleTest(unittest.TestCase): def setUp(self): self.orig_stdout = sys.stdout self.orig_stderr = sys.stderr self.orig_displayhook = sys.displayhook def tearDown(self): sys.stdout = self.orig_stdout sys.stderr = self.orig_stderr sys.displayhook = self.orig_displayhook def test_original_displayhook(self): import builtins out = io.StringIO() sys.stdout = out dh = sys.__displayhook__ self.assertRaises(TypeError, dh) if hasattr(builtins, "_"): del builtins._ dh(None) self.assertEqual(out.getvalue(), "") self.assertTrue(not hasattr(builtins, "_")) dh(42) self.assertEqual(out.getvalue(), "42\n") self.assertEqual(builtins._, 42) del sys.stdout self.assertRaises(RuntimeError, dh, 42) def test_lost_displayhook(self): del sys.displayhook code = compile("42", "", "single") self.assertRaises(RuntimeError, eval, code) def test_custom_displayhook(self): def baddisplayhook(obj): raise ValueError sys.displayhook = baddisplayhook code = compile("42", "", "single") self.assertRaises(ValueError, eval, code) def test_original_excepthook(self): err = io.StringIO() sys.stderr = err eh = sys.__excepthook__ self.assertRaises(TypeError, eh) try: raise ValueError(42) except ValueError as exc: eh(*sys.exc_info()) self.assertTrue(err.getvalue().endswith("ValueError: 42\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. def test_exit(self): self.assertRaises(TypeError, sys.exit, 42, 42) # call without argument try: sys.exit(0) except SystemExit as exc: self.assertEqual(exc.code, 0) except: self.fail("wrong exception") else: self.fail("no exception") # call with tuple argument with one entry # entry will be unpacked try: sys.exit(42) except SystemExit as exc: self.assertEqual(exc.code, 42) except: self.fail("wrong exception") else: self.fail("no exception") # call with integer argument try: sys.exit((42,)) except SystemExit as exc: self.assertEqual(exc.code, 42) except: self.fail("wrong exception") else: self.fail("no exception") # call with string argument try: sys.exit("exit") except SystemExit as exc: self.assertEqual(exc.code, "exit") except: self.fail("wrong exception") else: self.fail("no exception") # call with tuple argument with two entries try: sys.exit((17, 23)) except SystemExit as exc: self.assertEqual(exc.code, (17, 23)) except: self.fail("wrong exception") else: self.fail("no exception") # test that the exit machinery handles SystemExits properly rc = subprocess.call([sys.executable, "-c", "raise SystemExit(47)"]) self.assertEqual(rc, 47) def check_exit_message(code, expected): process = subprocess.Popen([sys.executable, "-c", code], stderr=subprocess.PIPE) stdout, stderr = process.communicate() self.assertEqual(process.returncode, 1) self.assertTrue(stderr.startswith(expected), "%s doesn't start with %s" % (ascii(stderr), ascii(expected))) # test that stderr buffer if 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") 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.assertTrue(isinstance(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): 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_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) def test_recursionlimit_recovery(self): # NOTE: this test is slightly fragile in that it depends on the current # recursion count when executing the test being low enough so as to # trigger the recursion recovery detection in the _Py_MakeEndRecCheck # macro (see ceval.h). oldlimit = sys.getrecursionlimit() def f(): f() try: for i in (50, 1000): # Issue #5392: stack overflow after hitting recursion limit twice sys.setrecursionlimit(i) self.assertRaises(RuntimeError, f) self.assertRaises(RuntimeError, f) finally: sys.setrecursionlimit(oldlimit) def test_recursionlimit_fatalerror(self): # A fatal error occurs if a second recursion limit is hit when recovering # from a first one. if os.name == "nt": raise unittest.SkipTest( "under Windows, test would generate a spurious crash dialog") code = textwrap.dedent(""" import sys def f(): try: f() except RuntimeError: f() sys.setrecursionlimit(%d) f()""") 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.assertTrue( b"Fatal Python error: Cannot recover from stack overflow" in err, err) def test_getwindowsversion(self): if hasattr(sys, "getwindowsversion"): v = sys.getwindowsversion() self.assertTrue(isinstance(v, tuple)) self.assertEqual(len(v), 5) self.assertTrue(isinstance(v[0], int)) self.assertTrue(isinstance(v[1], int)) self.assertTrue(isinstance(v[2], int)) self.assertTrue(isinstance(v[3], int)) self.assertTrue(isinstance(v[4], str)) def test_call_tracing(self): self.assertRaises(TypeError, sys.call_tracing, type, 2) def test_dlopenflags(self): if hasattr(sys, "setdlopenflags"): 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) 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+1) del n self.assertEqual(sys.getrefcount(None), c) if hasattr(sys, "gettotalrefcount"): self.assertTrue(isinstance(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. def test_current_frames(self): have_threads = True try: import _thread except ImportError: have_threads = False if have_threads: self.current_frames_with_threads() else: self.current_frames_without_threads() # Test sys._current_frames() in a WITH_THREADS build. def current_frames_with_threads(self): import threading, _thread 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(_thread.get_ident()) entered_g.set() leave_g.wait() t = threading.Thread(target=f123) t.start() entered_g.wait() # 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() main_id = _thread.get_ident() self.assertTrue(main_id in d) self.assertTrue(thread_id in 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.assertTrue(sourceline in ["leave_g.wait()", "entered_g.set()"]) # Reap the spawned thread. leave_g.set() t.join() # Test sys._current_frames() when thread support doesn't exist. def current_frames_without_threads(self): # Not much happens here: there is only one thread, with artificial # "thread id" 0. d = sys._current_frames() self.assertEqual(len(d), 1) self.assertTrue(0 in d) self.assertTrue(d[0] is sys._getframe()) def test_attributes(self): self.assertTrue(isinstance(sys.api_version, int)) self.assertTrue(isinstance(sys.argv, list)) self.assertTrue(sys.byteorder in ("little", "big")) self.assertTrue(isinstance(sys.builtin_module_names, tuple)) self.assertTrue(isinstance(sys.copyright, str)) self.assertTrue(isinstance(sys.exec_prefix, str)) self.assertTrue(isinstance(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.assertTrue(isinstance(sys.hexversion, int)) self.assertTrue(isinstance(sys.maxsize, int)) self.assertTrue(isinstance(sys.maxunicode, int)) self.assertTrue(isinstance(sys.platform, str)) self.assertTrue(isinstance(sys.prefix, str)) self.assertTrue(isinstance(sys.version, str)) vi = sys.version_info self.assertTrue(isinstance(vi[:], tuple)) self.assertEqual(len(vi), 5) self.assertTrue(isinstance(vi[0], int)) self.assertTrue(isinstance(vi[1], int)) self.assertTrue(isinstance(vi[2], int)) self.assertTrue(vi[3] in ("alpha", "beta", "candidate", "final")) self.assertTrue(isinstance(vi[4], int)) self.assertTrue(isinstance(vi.major, int)) self.assertTrue(isinstance(vi.minor, int)) self.assertTrue(isinstance(vi.micro, int)) self.assertTrue(vi.releaselevel in ("alpha", "beta", "candidate", "final")) self.assertTrue(isinstance(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)) 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 numruns numruns += 1 self.assertRaises(TypeError, sys.intern) s = "never interned before" + str(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_main_invalid_unicode(self): import locale non_decodable = b"\xff" encoding = locale.getpreferredencoding() try: non_decodable.decode(encoding) except UnicodeDecodeError: pass else: self.skipTest('%r is decodable with encoding %s' % (non_decodable, encoding)) code = b'print("' + non_decodable + b'")' p = subprocess.Popen([sys.executable, "-c", code], stderr=subprocess.PIPE) stdout, stderr = p.communicate() self.assertEqual(p.returncode, 1) self.assertTrue(b"UnicodeEncodeError:" in stderr, "%r not in %s" % (b"UnicodeEncodeError:", ascii(stderr))) def test_sys_flags(self): self.assertTrue(sys.flags) attrs = ("debug", "division_warning", "inspect", "interactive", "optimize", "dont_write_bytecode", "no_user_site", "no_site", "ignore_environment", "verbose", "bytes_warning") for attr in attrs: self.assertTrue(hasattr(sys.flags, attr), attr) self.assertEqual(type(getattr(sys.flags, attr)), int, attr) self.assertTrue(repr(sys.flags)) self.assertEqual(len(sys.flags), len(attrs)) 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.stdout.read() self.assertEqual(out, "\xa2\n".encode("cp424")) env["PYTHONIOENCODING"] = "ascii:replace" p = subprocess.Popen([sys.executable, "-c", 'print(chr(0xa2))'], stdout = subprocess.PIPE, env=env) out = p.stdout.read().strip() self.assertEqual(out, b'?') def test_executable(self): # Issue #7774: Ensure that sys.executable is an empty string if argv[0] # has been set to an 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"))]) class SizeofTest(unittest.TestCase): TPFLAGS_HAVE_GC = 1<<14 TPFLAGS_HEAPTYPE = 1<<9 def setUp(self): self.c = len(struct.pack('c', ' ')) self.H = len(struct.pack('H', 0)) self.i = len(struct.pack('i', 0)) self.l = len(struct.pack('l', 0)) self.P = len(struct.pack('P', 0)) # due to missing size_t information from struct, it is assumed that # sizeof(Py_ssize_t) = sizeof(void*) self.header = 'PP' self.vheader = self.header + 'P' if hasattr(sys, "gettotalrefcount"): self.header += '2P' self.vheader += '2P' self.longdigit = sys.int_info.sizeof_digit import _testcapi self.gc_headsize = _testcapi.SIZEOF_PYGC_HEAD self.file = open(test.support.TESTFN, 'wb') def tearDown(self): self.file.close() test.support.unlink(test.support.TESTFN) def check_sizeof(self, o, size): result = sys.getsizeof(o) # add GC header size if ((type(o) == type) and (o.__flags__ & self.TPFLAGS_HEAPTYPE) or\ ((type(o) != type) and (type(o).__flags__ & self.TPFLAGS_HAVE_GC))): size += self.gc_headsize msg = 'wrong size for %s: got %d, expected %d' \ % (type(o), result, size) self.assertEqual(result, size, msg) def calcsize(self, fmt): """Wrapper around struct.calcsize which enforces the alignment of the end of a structure to the alignment requirement of pointer. Note: This wrapper should only be used if a pointer member is included and no member with a size larger than a pointer exists. """ return struct.calcsize(fmt + '0P') def test_gc_head_size(self): # Check that the gc header size is added to objects tracked by the gc. h = self.header vh = self.vheader size = self.calcsize gc_header_size = self.gc_headsize # bool objects are not gc tracked self.assertEqual(sys.getsizeof(True), size(vh) + self.longdigit) # but lists are self.assertEqual(sys.getsizeof([]), size(vh + 'PP') + gc_header_size) def test_default(self): h = self.header vh = self.vheader size = self.calcsize self.assertEqual(sys.getsizeof(True), size(vh) + self.longdigit) self.assertEqual(sys.getsizeof(True, -1), size(vh) + self.longdigit) def test_objecttypes(self): # check all types defined in Objects/ h = self.header vh = self.vheader size = self.calcsize check = self.check_sizeof # bool check(True, size(vh) + self.longdigit) # buffer # XXX # builtin_function_or_method check(len, size(h + '3P')) # bytearray samples = [b'', b'u'*100000] for sample in samples: x = bytearray(sample) check(x, size(vh + 'iPP') + x.__alloc__() * self.c) # bytearray_iterator check(iter(bytearray()), size(h + 'PP')) # cell def get_cell(): x = 42 def inner(): return x return inner check(get_cell().__closure__[0], size(h + 'P')) # code check(get_cell().__code__, size(h + '5i8Pi2P')) # complex check(complex(0,1), size(h + '2d')) # method_descriptor (descriptor object) check(str.lower, size(h + '2PP')) # classmethod_descriptor (descriptor object) # XXX # member_descriptor (descriptor object) import datetime check(datetime.timedelta.days, size(h + '2PP')) # getset_descriptor (descriptor object) import collections check(collections.defaultdict.default_factory, size(h + '2PP')) # wrapper_descriptor (descriptor object) check(int.__add__, size(h + '2P2P')) # method-wrapper (descriptor object) check({}.__iter__, size(h + '2P')) # dict check({}, size(h + '3P2P' + 8*'P2P')) longdict = {1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8} check(longdict, size(h + '3P2P' + 8*'P2P') + 16*size('P2P')) # dictionary-keyiterator check({}.keys(), size(h + 'P')) # dictionary-valueiterator check({}.values(), size(h + 'P')) # dictionary-itemiterator check({}.items(), size(h + 'P')) # dictproxy class C(object): pass check(C.__dict__, size(h + 'P')) # BaseException check(BaseException(), size(h + '5P')) # UnicodeEncodeError check(UnicodeEncodeError("", "", 0, 0, ""), size(h + '5P 2P2PP')) # UnicodeDecodeError # XXX # check(UnicodeDecodeError("", "", 0, 0, ""), size(h + '5P2PP')) # UnicodeTranslateError check(UnicodeTranslateError("", 0, 1, ""), size(h + '5P 2P2PP')) # ellipses check(Ellipsis, size(h + '')) # EncodingMap import codecs, encodings.iso8859_3 x = codecs.charmap_build(encodings.iso8859_3.decoding_table) check(x, size(h + '32B2iB')) # enumerate check(enumerate([]), size(h + 'l3P')) # reverse check(reversed(''), size(h + 'PP')) # float check(float(0), size(h + 'd')) # sys.floatinfo check(sys.float_info, size(vh) + 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, size(vh + '12P3i' + CO_MAXBLOCKS*'3i' + 'P' + extras*'P')) # function def func(): pass check(func, size(h + '11P')) class c(): @staticmethod def foo(): pass @classmethod def bar(cls): pass # staticmethod check(foo, size(h + 'P')) # classmethod check(bar, size(h + 'P')) # generator def get_gen(): yield 1 check(get_gen(), size(h + 'Pi2P')) # iterator check(iter('abc'), size(h + 'lP')) # callable-iterator import re check(re.finditer('',''), size(h + '2P')) # list samples = [[], [1,2,3], ['1', '2', '3']] for sample in samples: check(sample, size(vh + 'PP') + len(sample)*self.P) # sortwrapper (list) # XXX # cmpwrapper (list) # XXX # listiterator (list) check(iter([]), size(h + 'lP')) # listreverseiterator (list) check(reversed([]), size(h + 'lP')) # long check(0, size(vh)) check(1, size(vh) + self.longdigit) check(-1, size(vh) + self.longdigit) PyLong_BASE = 2**sys.int_info.bits_per_digit check(int(PyLong_BASE), size(vh) + 2*self.longdigit) check(int(PyLong_BASE**2-1), size(vh) + 2*self.longdigit) check(int(PyLong_BASE**2), size(vh) + 3*self.longdigit) # memory check(memoryview(b''), size(h + 'P PP2P2i7P')) # module check(unittest, size(h + '3P')) # None check(None, size(h + '')) # NotImplementedType check(NotImplemented, size(h)) # object check(object(), size(h + '')) # 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(h + '4Pi')) # PyCapsule # XXX # rangeiterator check(iter(range(1)), size(h + '4l')) # reverse check(reversed(''), size(h + 'PP')) # range check(range(1), size(h + '3P')) check(range(66000), size(h + '3P')) # set # frozenset PySet_MINSIZE = 8 samples = [[], range(10), range(50)] s = size(h + '3P2P' + PySet_MINSIZE*'lP' + 'lP') 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*struct.calcsize('lP')) check(frozenset(sample), s + newsize*struct.calcsize('lP')) # setiterator check(iter(set()), size(h + 'P3P')) # slice check(slice(0), size(h + '3P')) # super check(super(int), size(h + '3P')) # tuple check((), size(vh)) check((1,2,3), size(vh) + 3*self.P) # type # (PyTypeObject + PyNumberMethods + PyMappingMethods + # PySequenceMethods + PyBufferProcs) s = size(vh + 'P2P15Pl4PP9PP11PI') + size('16Pi17P 3P 10P 2P 2P') check(int, s) # class class newstyleclass(object): pass check(newstyleclass, s) # unicode usize = len('\0'.encode('unicode-internal')) samples = ['', '1'*100] # we need to test for both sizes, because we don't know if the string # has been cached for s in samples: basicsize = size(h + 'PPliP') + usize * (len(s) + 1) check(s, basicsize) # weakref import weakref check(weakref.ref(int), size(h + '2Pl2P')) # weakproxy # XXX # weakcallableproxy check(weakref.proxy(int), size(h + '2Pl2P')) def test_pythontypes(self): # check all types defined in Python/ h = self.header vh = self.vheader size = self.calcsize check = self.check_sizeof # _ast.AST import _ast check(_ast.AST(), size(h + '')) # imp.NullImporter import imp check(imp.NullImporter(self.file.name), size(h + '')) try: raise TypeError except TypeError: tb = sys.exc_info()[2] # traceback if tb != None: check(tb, size(h + '2P2i')) # symtable entry # XXX # sys.flags check(sys.flags, size(vh) + self.P * len(sys.flags)) def test_getfilesystemencoding(self): import codecs def check_fsencoding(fs_encoding): if sys.platform == 'darwin': self.assertEqual(fs_encoding, 'utf-8') elif fs_encoding is None: return codecs.lookup(fs_encoding) fs_encoding = sys.getfilesystemencoding() check_fsencoding(fs_encoding) # Even in C locale try: sys.executable.encode('ascii') except UnicodeEncodeError: # Python doesn't start with ASCII locale if its path is not ASCII, # see issue #8611 pass else: env = os.environ.copy() env['LANG'] = 'C' output = subprocess.check_output( [sys.executable, "-c", "import sys; print(sys.getfilesystemencoding())"], env=env) fs_encoding = output.rstrip().decode('ascii') check_fsencoding(fs_encoding) def test_setfilesystemencoding(self): old = sys.getfilesystemencoding() try: sys.setfilesystemencoding("iso-8859-1") self.assertEqual(sys.getfilesystemencoding(), "iso-8859-1") finally: sys.setfilesystemencoding(old) try: self.assertRaises(LookupError, sys.setfilesystemencoding, "xxx") finally: sys.setfilesystemencoding(old) def test_main(): test.support.run_unittest(SysModuleTest, SizeofTest) if __name__ == "__main__": test_main()