diff --git a/Doc/library/locale.rst b/Doc/library/locale.rst
index b04442bc162..9a0c570533a 100644
--- a/Doc/library/locale.rst
+++ b/Doc/library/locale.rst
@@ -147,6 +147,16 @@ The :mod:`locale` module defines the following exception and functions:
| ``CHAR_MAX`` | Nothing is specified in this locale. |
+--------------+-----------------------------------------+
+ The function sets temporarily the ``LC_CTYPE`` locale to the ``LC_NUMERIC``
+ locale to decode ``decimal_point`` and ``thousands_sep`` byte strings if
+ they are non-ASCII or longer than 1 byte, and the ``LC_NUMERIC`` locale is
+ different than the ``LC_CTYPE`` locale. This temporary change affects other
+ threads.
+
+ .. versionchanged:: 3.6.5
+ The function now sets temporarily the ``LC_CTYPE`` locale to the
+ ``LC_NUMERIC`` locale in some cases.
+
.. function:: nl_langinfo(option)
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index 196a4c00056..d8a1647e8b5 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -1599,6 +1599,20 @@ expression support in the :mod:`re` module).
See :ref:`formatstrings` for a description of the various formatting options
that can be specified in format strings.
+ .. note::
+ When formatting a number (:class:`int`, :class:`float`, :class:`float`
+ and subclasses) with the ``n`` type (ex: ``'{:n}'.format(1234)``), the
+ function sets temporarily the ``LC_CTYPE`` locale to the ``LC_NUMERIC``
+ locale to decode ``decimal_point`` and ``thousands_sep`` fields of
+ :c:func:`localeconv` if they are non-ASCII or longer than 1 byte, and the
+ ``LC_NUMERIC`` locale is different than the ``LC_CTYPE`` locale. This
+ temporary change affects other threads.
+
+ .. versionchanged:: 3.6.5
+ When formatting a number with the ``n`` type, the function sets
+ temporarily the ``LC_CTYPE`` locale to the ``LC_NUMERIC`` locale in some
+ cases.
+
.. method:: str.format_map(mapping)
diff --git a/Doc/whatsnew/3.6.rst b/Doc/whatsnew/3.6.rst
index 847b50140a6..f83508c9250 100644
--- a/Doc/whatsnew/3.6.rst
+++ b/Doc/whatsnew/3.6.rst
@@ -2346,3 +2346,11 @@ It has been replaced by the new ``make regen-all`` target.
(Contributed by Victor Stinner in :issue:`23404`.)
.. versionchanged:: 3.6.2
+
+
+Notable changes in Python 3.6.5
+===============================
+
+The :func:`locale.localeconv` function now sets temporarily the ``LC_CTYPE``
+locale to the ``LC_NUMERIC`` locale in some cases.
+(Contributed by Victor Stinner in :issue:`31900`.)
diff --git a/Include/fileutils.h b/Include/fileutils.h
index 900c70faad7..875715df97a 100644
--- a/Include/fileutils.h
+++ b/Include/fileutils.h
@@ -119,6 +119,11 @@ PyAPI_FUNC(int) _Py_get_blocking(int fd);
PyAPI_FUNC(int) _Py_set_blocking(int fd, int blocking);
#endif /* !MS_WINDOWS */
+PyAPI_FUNC(int) _Py_GetLocaleconvNumeric(
+ PyObject **decimal_point,
+ PyObject **thousands_sep,
+ const char **grouping);
+
#endif /* Py_LIMITED_API */
#ifdef __cplusplus
diff --git a/Modules/_localemodule.c b/Modules/_localemodule.c
index 71c9146ccb8..95b370b1ad0 100644
--- a/Modules/_localemodule.c
+++ b/Modules/_localemodule.c
@@ -171,12 +171,6 @@ PyLocale_localeconv(PyObject* self)
RESULT(#i, x); \
} while (0)
- /* Numeric information */
- RESULT_STRING(decimal_point);
- RESULT_STRING(thousands_sep);
- x = copy_grouping(l->grouping);
- RESULT("grouping", x);
-
/* Monetary information */
RESULT_STRING(int_curr_symbol);
RESULT_STRING(currency_symbol);
@@ -195,6 +189,32 @@ PyLocale_localeconv(PyObject* self)
RESULT_INT(n_sep_by_space);
RESULT_INT(p_sign_posn);
RESULT_INT(n_sign_posn);
+
+ /* Numeric information */
+ PyObject *decimal_point, *thousands_sep;
+ const char *grouping;
+ if (_Py_GetLocaleconvNumeric(&decimal_point,
+ &thousands_sep,
+ &grouping) < 0) {
+ goto failed;
+ }
+
+ if (PyDict_SetItemString(result, "decimal_point", decimal_point) < 0) {
+ Py_DECREF(decimal_point);
+ Py_DECREF(thousands_sep);
+ goto failed;
+ }
+ Py_DECREF(decimal_point);
+
+ if (PyDict_SetItemString(result, "thousands_sep", thousands_sep) < 0) {
+ Py_DECREF(thousands_sep);
+ goto failed;
+ }
+ Py_DECREF(thousands_sep);
+
+ x = copy_grouping(grouping);
+ RESULT("grouping", x);
+
return result;
failed:
diff --git a/Python/fileutils.c b/Python/fileutils.c
index 97505e5bc6d..14dd81b03f0 100644
--- a/Python/fileutils.c
+++ b/Python/fileutils.c
@@ -1597,3 +1597,80 @@ _Py_set_blocking(int fd, int blocking)
return -1;
}
#endif
+
+
+int
+_Py_GetLocaleconvNumeric(PyObject **decimal_point, PyObject **thousands_sep,
+ const char **grouping)
+{
+ int res = -1;
+
+ struct lconv *lc = localeconv();
+
+ int change_locale = 0;
+ if (decimal_point != NULL &&
+ (strlen(lc->decimal_point) > 1 || ((unsigned char)lc->decimal_point[0]) > 127))
+ {
+ change_locale = 1;
+ }
+ if (thousands_sep != NULL &&
+ (strlen(lc->thousands_sep) > 1 || ((unsigned char)lc->thousands_sep[0]) > 127))
+ {
+ change_locale = 1;
+ }
+
+ /* Keep a copy of the LC_CTYPE locale */
+ char *oldloc = NULL, *loc = NULL;
+ if (change_locale) {
+ oldloc = setlocale(LC_CTYPE, NULL);
+ if (!oldloc) {
+ PyErr_SetString(PyExc_RuntimeWarning, "faild to get LC_CTYPE locale");
+ return -1;
+ }
+
+ oldloc = _PyMem_Strdup(oldloc);
+ if (!oldloc) {
+ PyErr_NoMemory();
+ return -1;
+ }
+
+ loc = setlocale(LC_NUMERIC, NULL);
+ if (loc != NULL && strcmp(loc, oldloc) == 0) {
+ loc = NULL;
+ }
+
+ if (loc != NULL) {
+ /* Only set the locale temporarilty the LC_CTYPE locale
+ if LC_NUMERIC locale is different than LC_CTYPE locale and
+ decimal_point and/or thousands_sep are non-ASCII or longer than
+ 1 byte */
+ setlocale(LC_CTYPE, loc);
+ }
+ }
+
+ if (decimal_point != NULL) {
+ *decimal_point = PyUnicode_DecodeLocale(lc->decimal_point, NULL);
+ if (*decimal_point == NULL) {
+ goto error;
+ }
+ }
+ if (thousands_sep != NULL) {
+ *thousands_sep = PyUnicode_DecodeLocale(lc->thousands_sep, NULL);
+ if (*thousands_sep == NULL) {
+ goto error;
+ }
+ }
+
+ if (grouping != NULL) {
+ *grouping = lc->grouping;
+ }
+
+ res = 0;
+
+error:
+ if (loc != NULL) {
+ setlocale(LC_CTYPE, oldloc);
+ }
+ PyMem_Free(oldloc);
+ return res;
+}
diff --git a/Python/formatter_unicode.c b/Python/formatter_unicode.c
index d2be76f1e1a..d3ef650e6ce 100644
--- a/Python/formatter_unicode.c
+++ b/Python/formatter_unicode.c
@@ -707,18 +707,11 @@ get_locale_info(enum LocaleType type, LocaleInfo *locale_info)
{
switch (type) {
case LT_CURRENT_LOCALE: {
- struct lconv *locale_data = localeconv();
- locale_info->decimal_point = PyUnicode_DecodeLocale(
- locale_data->decimal_point,
- NULL);
- if (locale_info->decimal_point == NULL)
+ if (_Py_GetLocaleconvNumeric(&locale_info->decimal_point,
+ &locale_info->thousands_sep,
+ &locale_info->grouping) < 0) {
return -1;
- locale_info->thousands_sep = PyUnicode_DecodeLocale(
- locale_data->thousands_sep,
- NULL);
- if (locale_info->thousands_sep == NULL)
- return -1;
- locale_info->grouping = locale_data->grouping;
+ }
break;
}
case LT_DEFAULT_LOCALE: