diff --git a/Doc/library/development.rst b/Doc/library/development.rst index d2b5fa2aa4f5f82..ab34e1f7ce5f64e 100644 --- a/Doc/library/development.rst +++ b/Doc/library/development.rst @@ -24,3 +24,6 @@ The list of modules described in this chapter is: unittest.mock-examples.rst 2to3.rst test.rst + +See also the Python development mode: the :option:`-X` ``dev`` option and +:envvar:`PYTHONDEVMODE` environment variable. diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst index faf540c4ea43b21..9e47681804b5eb5 100644 --- a/Doc/library/sys.rst +++ b/Doc/library/sys.rst @@ -334,6 +334,7 @@ always available. :const:`bytes_warning` :option:`-b` :const:`quiet` :option:`-q` :const:`hash_randomization` :option:`-R` + :const:`dev_mode` :option:`-X` ``dev`` ============================= ============================= .. versionchanged:: 3.2 @@ -345,6 +346,9 @@ always available. .. versionchanged:: 3.3 Removed obsolete ``division_warning`` attribute. + .. versionchanged:: 3.7 + Added ``dev_mode`` attribute for the new :option:`-X` ``dev`` flag. + .. data:: float_info diff --git a/Doc/using/cmdline.rst b/Doc/using/cmdline.rst index e6189fd8127fe55..d110ae3baf28004 100644 --- a/Doc/using/cmdline.rst +++ b/Doc/using/cmdline.rst @@ -411,7 +411,7 @@ Miscellaneous options nested imports). Note that its output may be broken in multi-threaded application. Typical usage is ``python3 -X importtime -c 'import asyncio'``. See also :envvar:`PYTHONPROFILEIMPORTTIME`. - * ``-X dev``: enable CPython's "developer mode", introducing additional + * ``-X dev``: enable CPython's "development mode", introducing additional runtime checks which are too expensive to be enabled by default. It should not be more verbose than the default if the code is correct: new warnings are only emitted when an issue is detected. Effect of the developer mode: @@ -426,6 +426,8 @@ Miscellaneous options * Enable the :mod:`faulthandler` module to dump the Python traceback on a crash. * Enable :ref:`asyncio debug mode `. + * Set the :attr:`~sys.flags.dev_mode` attribute of :attr:`sys.flags` to + ``True`` It also allows passing arbitrary values and retrieving them through the :data:`sys._xoptions` dictionary. @@ -796,6 +798,14 @@ conflict. .. versionadded:: 3.7 See :pep:`538` for more details. + +.. envvar:: PYTHONDEVMODE + + If this environment variable is set to a non-empty string, enable the + CPython "development mode". See the :option:`-X` ``dev`` option. + + .. versionadded:: 3.7 + Debug-mode variables ~~~~~~~~~~~~~~~~~~~~ diff --git a/Doc/whatsnew/3.7.rst b/Doc/whatsnew/3.7.rst index e4600fe5ffd3169..0cb2f7259b9deda 100644 --- a/Doc/whatsnew/3.7.rst +++ b/Doc/whatsnew/3.7.rst @@ -185,10 +185,10 @@ resolution on Linux and Windows. PEP written and implemented by Victor Stinner -New Developer Mode: -X dev --------------------------- +New Development Mode: -X dev +---------------------------- -Add a new "developer mode": ``-X dev`` command line option to enable debug +Add a new "development mode": ``-X dev`` command line option to enable debug checks at runtime. In short, ``python3 -X dev ...`` behaves as ``PYTHONMALLOC=debug python3 -W @@ -371,6 +371,11 @@ string expression pattern for braced placeholders and non-braced placeholders separately. (Contributed by Barry Warsaw in :issue:`1198569`.) +sys +--- + +Added :attr:`sys.flags.dev_mode` flag for the new development mode. + time ---- diff --git a/Lib/asyncio/coroutines.py b/Lib/asyncio/coroutines.py index 3e305f90abb9fea..2b9ea19ed8da498 100644 --- a/Lib/asyncio/coroutines.py +++ b/Lib/asyncio/coroutines.py @@ -29,11 +29,9 @@ def _is_debug_mode(): # before you define your coroutines. A downside of using this feature # is that tracebacks show entries for the CoroWrapper.__next__ method # when _DEBUG is true. - debug = (not sys.flags.ignore_environment and - bool(os.environ.get('PYTHONASYNCIODEBUG'))) - if hasattr(sys, '_xoptions') and 'dev' in sys._xoptions: - debug = True - return debug + return (sys.flags.dev_mode + or (not sys.flags.ignore_environment + and bool(os.environ.get('PYTHONASYNCIODEBUG')))) _DEBUG = _is_debug_mode() diff --git a/Lib/test/test_cmd_line.py b/Lib/test/test_cmd_line.py index 96405e70afc0c11..383302bad8b549d 100644 --- a/Lib/test/test_cmd_line.py +++ b/Lib/test/test_cmd_line.py @@ -508,14 +508,18 @@ def test_sys_flags_set(self): with self.subTest(envar_value=value): assert_python_ok('-c', code, **env_vars) - def run_xdev(self, *args, check_exitcode=True): + def run_xdev(self, *args, check_exitcode=True, xdev=True): env = dict(os.environ) env.pop('PYTHONWARNINGS', None) + env.pop('PYTHONDEVMODE', None) # Force malloc() to disable the debug hooks which are enabled # by default for Python compiled in debug mode env['PYTHONMALLOC'] = 'malloc' - args = (sys.executable, '-X', 'dev', *args) + if xdev: + args = (sys.executable, '-X', 'dev', *args) + else: + args = (sys.executable, *args) proc = subprocess.run(args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, @@ -526,6 +530,14 @@ def run_xdev(self, *args, check_exitcode=True): return proc.stdout.rstrip() def test_xdev(self): + # sys.flags.dev_mode + code = "import sys; print(sys.flags.dev_mode)" + out = self.run_xdev("-c", code, xdev=False) + self.assertEqual(out, "False") + out = self.run_xdev("-c", code) + self.assertEqual(out, "True") + + # Warnings code = ("import sys, warnings; " "print(' '.join('%s::%s' % (f[0], f[2].__name__) " "for f in warnings.filters))") @@ -555,6 +567,7 @@ def test_xdev(self): "default::ResourceWarning " "default::Warning") + # Memory allocator debug hooks try: import _testcapi except ImportError: @@ -569,6 +582,7 @@ def test_xdev(self): alloc_name = "malloc_debug" self.assertEqual(out, alloc_name) + # Faulthandler try: import faulthandler except ImportError: @@ -581,6 +595,7 @@ def test_xdev(self): def check_pythonmalloc(self, env_var, name): code = 'import _testcapi; print(_testcapi.pymem_getallocatorsname())' env = dict(os.environ) + env.pop('PYTHONDEVMODE', None) if env_var is not None: env['PYTHONMALLOC'] = env_var else: @@ -621,6 +636,24 @@ def test_pythonmalloc(self): with self.subTest(env_var=env_var, name=name): self.check_pythonmalloc(env_var, name) + def test_pythondevmode_env(self): + # Test the PYTHONDEVMODE environment variable + code = "import sys; print(sys.flags.dev_mode)" + env = dict(os.environ) + env.pop('PYTHONDEVMODE', None) + args = (sys.executable, '-c', code) + + proc = subprocess.run(args, stdout=subprocess.PIPE, + universal_newlines=True, env=env) + self.assertEqual(proc.stdout.rstrip(), 'False') + self.assertEqual(proc.returncode, 0, proc) + + env['PYTHONDEVMODE'] = '1' + proc = subprocess.run(args, stdout=subprocess.PIPE, + universal_newlines=True, env=env) + self.assertEqual(proc.stdout.rstrip(), 'True') + self.assertEqual(proc.returncode, 0, proc) + class IgnoreEnvironmentTest(unittest.TestCase): diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py index 4b8fcb9540ffe58..6346094ad08b4cc 100644 --- a/Lib/test/test_sys.py +++ b/Lib/test/test_sys.py @@ -526,10 +526,12 @@ def test_sys_flags(self): attrs = ("debug", "inspect", "interactive", "optimize", "dont_write_bytecode", "no_user_site", "no_site", "ignore_environment", "verbose", - "bytes_warning", "quiet", "hash_randomization", "isolated") + "bytes_warning", "quiet", "hash_randomization", "isolated", + "dev_mode") for attr in attrs: self.assertTrue(hasattr(sys.flags, attr), attr) - self.assertEqual(type(getattr(sys.flags, attr)), int, 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)) diff --git a/Misc/NEWS.d/next/Library/2017-11-29-00-42-47.bpo-321010.-axD5l.rst b/Misc/NEWS.d/next/Library/2017-11-29-00-42-47.bpo-321010.-axD5l.rst new file mode 100644 index 000000000000000..715a269a5c0a008 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2017-11-29-00-42-47.bpo-321010.-axD5l.rst @@ -0,0 +1 @@ +Add :attr:`sys.flags.dev_mode` flag diff --git a/Modules/main.c b/Modules/main.c index ec33b5f086f0f1b..e9d524a1463627c 100644 --- a/Modules/main.c +++ b/Modules/main.c @@ -124,7 +124,8 @@ static const char usage_6[] = " hooks.\n" "PYTHONCOERCECLOCALE: if this variable is set to 0, it disables the locale\n" " coercion behavior. Use PYTHONCOERCECLOCALE=warn to request display of\n" -" locale coercion and locale compatibility warnings on stderr.\n"; +" locale coercion and locale compatibility warnings on stderr.\n" +"PYTHONDEVMODE: enable the development mode.\n"; static void pymain_usage(int error, const wchar_t* program) @@ -1520,7 +1521,9 @@ pymain_parse_envvars(_PyMain *pymain) if (pymain_init_tracemalloc(pymain) < 0) { return -1; } - if (pymain_get_xoption(pymain, L"dev")) { + if (pymain_get_xoption(pymain, L"dev" ) || + pymain_get_env_var("PYTHONDEVMODE")) + { core_config->dev_mode = 1; core_config->faulthandler = 1; core_config->allocator = "debug"; diff --git a/Python/sysmodule.c b/Python/sysmodule.c index d786739188a8160..64bc14e9c3d7339 100644 --- a/Python/sysmodule.c +++ b/Python/sysmodule.c @@ -1814,6 +1814,7 @@ static PyStructSequence_Field flags_fields[] = { {"quiet", "-q"}, {"hash_randomization", "-R"}, {"isolated", "-I"}, + {"dev_mode", "-X dev"}, {0} }; @@ -1821,7 +1822,7 @@ static PyStructSequence_Desc flags_desc = { "sys.flags", /* name */ flags__doc__, /* doc */ flags_fields, /* fields */ - 13 + 14 }; static PyObject* @@ -1829,6 +1830,7 @@ make_flags(void) { int pos = 0; PyObject *seq; + _PyCoreConfig *core_config = &_PyGILState_GetInterpreterStateUnsafe()->core_config; seq = PyStructSequence_New(&FlagsType); if (seq == NULL) @@ -1853,6 +1855,7 @@ make_flags(void) SetFlag(Py_HashRandomizationFlag); SetFlag(Py_IsolatedFlag); #undef SetFlag + PyStructSequence_SET_ITEM(seq, pos++, PyBool_FromLong(core_config->dev_mode)); if (PyErr_Occurred()) { Py_DECREF(seq);