bpo-42236: os.device_encoding() respects UTF-8 Mode (GH-23119)

On Unix, the os.device_encoding() function now returns 'UTF-8' rather
than the device encoding if the Python UTF-8 Mode is enabled.
This commit is contained in:
Victor Stinner 2020-11-04 11:20:10 +01:00 committed by GitHub
parent 0001a1b69e
commit 3529718925
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
5 changed files with 52 additions and 17 deletions

View File

@ -113,6 +113,8 @@ of the UTF-8 encoding:
:ref:`error handler <error-handlers>` being enabled for :data:`sys.stdin`
and :data:`sys.stdout` (:data:`sys.stderr` continues to use
``backslashreplace`` as it does in the default locale-aware mode)
* On Unix, :func:`os.device_encoding` returns ``'UTF-8'``. rather than the
device encoding.
Note that the standard stream settings in UTF-8 mode can be overridden by
:envvar:`PYTHONIOENCODING` (just as they can be in the default locale-aware
@ -808,6 +810,12 @@ as internal buffering of data.
Return a string describing the encoding of the device associated with *fd*
if it is connected to a terminal; else return :const:`None`.
On Unix, if the :ref:`Python UTF-8 Mode <utf8-mode>` is enabled, return
``'UTF-8'`` rather than the device encoding.
.. versionchanged:: 3.10
On Unix, the function now implements the Python UTF-8 Mode.
.. function:: dup(fd)

View File

@ -3,11 +3,13 @@ Test the implementation of the PEP 540: the UTF-8 Mode.
"""
import locale
import subprocess
import sys
import textwrap
import unittest
from test import support
from test.support.script_helper import assert_python_ok, assert_python_failure
from test.support import os_helper
MS_WINDOWS = (sys.platform == 'win32')
@ -250,6 +252,31 @@ class UTF8ModeTests(unittest.TestCase):
out = self.get_output('-X', 'utf8', '-E', '-c', code)
self.assertEqual(out, '1')
@unittest.skipIf(MS_WINDOWS,
"os.device_encoding() doesn't implement "
"the UTF-8 Mode on Windows")
def test_device_encoding(self):
# Use stdout as TTY
if not sys.stdout.isatty():
self.skipTest("sys.stdout is not a TTY")
filename = 'out.txt'
self.addCleanup(os_helper.unlink, filename)
code = (f'import os, sys; fd = sys.stdout.fileno(); '
f'out = open({filename!r}, "w", encoding="utf-8"); '
f'print(os.isatty(fd), os.device_encoding(fd), file=out); '
f'out.close()')
cmd = [sys.executable, '-X', 'utf8', '-c', code]
# The stdout TTY is inherited to the child process
proc = subprocess.run(cmd, text=True)
self.assertEqual(proc.returncode, 0, proc)
# In UTF-8 Mode, device_encoding(fd) returns "UTF-8" if fd is a TTY
with open(filename, encoding="utf8") as fp:
out = fp.read().rstrip()
self.assertEqual(out, 'True UTF-8')
if __name__ == "__main__":
unittest.main()

View File

@ -0,0 +1,3 @@
On Unix, the :func:`os.device_encoding` function now returns ``'UTF-8'`` rather
than the device encoding if the :ref:`Python UTF-8 Mode <utf8-mode>` is
enabled.

View File

@ -55,9 +55,6 @@ get_surrogateescape(_Py_error_handler errors, int *surrogateescape)
PyObject *
_Py_device_encoding(int fd)
{
#if defined(MS_WINDOWS)
UINT cp;
#endif
int valid;
_Py_BEGIN_SUPPRESS_IPH
valid = isatty(fd);
@ -66,6 +63,7 @@ _Py_device_encoding(int fd)
Py_RETURN_NONE;
#if defined(MS_WINDOWS)
UINT cp;
if (fd == 0)
cp = GetConsoleCP();
else if (fd == 1 || fd == 2)
@ -74,16 +72,14 @@ _Py_device_encoding(int fd)
cp = 0;
/* GetConsoleCP() and GetConsoleOutputCP() return 0 if the application
has no console */
if (cp != 0)
return PyUnicode_FromFormat("cp%u", (unsigned int)cp);
#elif defined(CODESET)
{
char *codeset = nl_langinfo(CODESET);
if (codeset != NULL && codeset[0] != 0)
return PyUnicode_FromString(codeset);
if (cp == 0) {
Py_RETURN_NONE;
}
return PyUnicode_FromFormat("cp%u", (unsigned int)cp);
#else
return _Py_GetLocaleEncodingObject();
#endif
Py_RETURN_NONE;
}
#if !defined(_Py_FORCE_UTF8_FS_ENCODING) && !defined(MS_WINDOWS)

View File

@ -1515,8 +1515,8 @@ config_init_stdio_encoding(PyConfig *config,
{
PyStatus status;
/* If Py_SetStandardStreamEncoding() have been called, use these
parameters. */
/* If Py_SetStandardStreamEncoding() has been called, use its
arguments if they are not NULL. */
if (config->stdio_encoding == NULL && _Py_StandardStreamEncoding != NULL) {
status = CONFIG_SET_BYTES_STR(config, &config->stdio_encoding,
_Py_StandardStreamEncoding,
@ -1535,6 +1535,7 @@ config_init_stdio_encoding(PyConfig *config,
}
}
// Exit if encoding and errors are defined
if (config->stdio_encoding != NULL && config->stdio_errors != NULL) {
return _PyStatus_OK();
}
@ -1634,12 +1635,12 @@ config_get_fs_encoding(PyConfig *config, const PyPreConfig *preconfig,
if (preconfig->utf8_mode) {
return PyConfig_SetString(config, fs_encoding, L"utf-8");
}
else if (_Py_GetForceASCII()) {
if (_Py_GetForceASCII()) {
return PyConfig_SetString(config, fs_encoding, L"ascii");
}
else {
return config_get_locale_encoding(config, preconfig, fs_encoding);
}
return config_get_locale_encoding(config, preconfig, fs_encoding);
#endif // !MS_WINDOWS
}