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StanFromIreland Mar 9, 2025
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7 changes: 6 additions & 1 deletion Doc/library/datetime.rst
Original file line number Diff line number Diff line change
Expand Up @@ -2631,6 +2631,10 @@ differences between platforms in handling of unsupported format specifiers.
.. versionadded:: 3.12
``%:z`` was added.

.. versionchanged:: next
Non-ASCII digits are now rejected by ``strptime`` for non-locale-specific
numerical directives.

Technical Detail
^^^^^^^^^^^^^^^^

Expand Down Expand Up @@ -2670,7 +2674,8 @@ Notes:
Because the format depends on the current locale, care should be taken when
making assumptions about the output value. Field orderings will vary (for
example, "month/day/year" versus "day/month/year"), and the output may
contain non-ASCII characters.
contain non-ASCII characters. :meth:`~.datetime.strptime` rejects non-ASCII
digits for non-locale-specific numeric format codes (e.g. ``%Y``, ``%H``, etc).

(2)
The :meth:`~.datetime.strptime` method can parse years in the full [1, 9999] range, but
Expand Down
13 changes: 10 additions & 3 deletions Doc/library/time.rst
Original file line number Diff line number Diff line change
Expand Up @@ -567,6 +567,10 @@ Functions
When used with the :func:`strptime` function, ``%U`` and ``%W`` are only used in
calculations when the day of the week and the year are specified.

(5)
The :func:`strptime` function does not accept non-ASCII digits for
non-locale-specific numeric format codes.

Here is an example, a format for dates compatible with that specified in the
:rfc:`2822` Internet email standard. [1]_ ::

Expand All @@ -590,9 +594,8 @@ Functions

.. function:: strptime(string[, format])

Parse a string representing a time according to a format. The return value
is a :class:`struct_time` as returned by :func:`gmtime` or
:func:`localtime`.
Parse a string representing a time according to a format string. The return
value is a :class:`struct_time` as returned by :func:`gmtime` or :func:`localtime`.

The *format* parameter uses the same directives as those used by
:func:`strftime`; it defaults to ``"%a %b %d %H:%M:%S %Y"`` which matches the
Expand Down Expand Up @@ -620,6 +623,10 @@ Functions
and thus does not necessarily support all directives available that are not
documented as supported.

.. versionchanged:: next
Non-ASCII digits are now rejected by ``strptime`` for non-locale-specific
format codes.


.. class:: struct_time

Expand Down
1 change: 1 addition & 0 deletions Doc/whatsnew/3.14.rst
Original file line number Diff line number Diff line change
Expand Up @@ -1370,6 +1370,7 @@ datetime
* Add :meth:`datetime.time.strptime` and :meth:`datetime.date.strptime`.
(Contributed by Wannes Boeykens in :gh:`41431`.)


decimal
-------

Expand Down
19 changes: 19 additions & 0 deletions Doc/whatsnew/3.15.rst
Original file line number Diff line number Diff line change
Expand Up @@ -89,6 +89,16 @@ New modules
Improved modules
================

datetime
--------

* When using digits in :meth:`datetime.date.strptime`,
:meth:`datetime.datetime.strptime`, or :meth:`datetime.time.strptime`, a
:exc:`ValueError` is raised if non-ASCII digits are specified for
non-locale-specific numeric format codes.
(Contributed by Stan Ulbrych in :gh:`131008`.)


dbm
---

Expand Down Expand Up @@ -171,6 +181,14 @@ tarfile
and :cve:`2025-4435`.)


time
----

* When using digits in :func:`time.strptime`, a :exc:`ValueError` is raised if
non-ASCII digits are specified for non-locale-specific numeric format codes.
(Contributed by Stan Ulbrych in :gh:`131008`.)


zlib
----

Expand All @@ -181,6 +199,7 @@ zlib
(Contributed by Bénédikt Tran in :gh:`134635`.)



.. Add improved modules above alphabetically, not here at the end.

Optimizations
Expand Down
22 changes: 11 additions & 11 deletions Lib/_strptime.py
Original file line number Diff line number Diff line change
Expand Up @@ -286,23 +286,23 @@ def __init__(self, locale_time=None):
base = super()
mapping = {
# The " [1-9]" part of the regex is to make %c from ANSI C work
'd': r"(?P<d>3[0-1]|[1-2]\d|0[1-9]|[1-9]| [1-9])",
'd': r"(?P<d>3[0-1]|[1-2][0-9]|0[1-9]|[1-9]| [1-9])",
'f': r"(?P<f>[0-9]{1,6})",
'H': r"(?P<H>2[0-3]|[0-1]\d|\d)",
'H': r"(?P<H>2[0-3]|[0-1][0-9]|[0-9])",
'I': r"(?P<I>1[0-2]|0[1-9]|[1-9]| [1-9])",
'G': r"(?P<G>\d\d\d\d)",
'j': r"(?P<j>36[0-6]|3[0-5]\d|[1-2]\d\d|0[1-9]\d|00[1-9]|[1-9]\d|0[1-9]|[1-9])",
'G': r"(?P<G>[0-9][0-9][0-9][0-9])",
'j': r"(?P<j>36[0-6]|3[0-5][0-9]|[1-2][0-9][0-9]|0[1-9][0-9]|00[1-9]|[1-9][0-9]|0[1-9]|[1-9])",
'm': r"(?P<m>1[0-2]|0[1-9]|[1-9])",
'M': r"(?P<M>[0-5]\d|\d)",
'S': r"(?P<S>6[0-1]|[0-5]\d|\d)",
'U': r"(?P<U>5[0-3]|[0-4]\d|\d)",
'M': r"(?P<M>[0-5][0-9]|[0-9])",
'S': r"(?P<S>6[0-1]|[0-5][0-9]|[0-9])",
'U': r"(?P<U>5[0-3]|[0-4][0-9]|[0-9])",
'w': r"(?P<w>[0-6])",
'u': r"(?P<u>[1-7])",
'V': r"(?P<V>5[0-3]|0[1-9]|[1-4]\d|\d)",
'V': r"(?P<V>5[0-3]|0[1-9]|[1-4][0-9]|[0-9])",
# W is set below by using 'U'
'y': r"(?P<y>\d\d)",
'Y': r"(?P<Y>\d\d\d\d)",
'z': r"(?P<z>([+-]\d\d:?[0-5]\d(:?[0-5]\d(\.\d{1,6})?)?)|(?-i:Z))?",
'y': r"(?P<y>[0-9][0-9])",
'Y': r"(?P<Y>[0-9]{4})",
'z': r"(?P<z>([+-][0-9][0-9]:?[0-5][0-9](:?[0-5][0-9](\.[0-9]{1,6})?)?)|(?-i:Z))?",
'A': self.__seqToRE(self.locale_time.f_weekday, 'A'),
'a': self.__seqToRE(self.locale_time.a_weekday, 'a'),
'B': self.__seqToRE(self.locale_time.f_month[1:], 'B'),
Expand Down
10 changes: 9 additions & 1 deletion Lib/test/datetimetester.py
Original file line number Diff line number Diff line change
Expand Up @@ -2924,6 +2924,14 @@ def test_strptime(self):
with self.assertRaises(ValueError): strptime("-000", "%z")
with self.assertRaises(ValueError): strptime("z", "%z")

# test only ascii is allowed
with self.assertRaises(ValueError): strptime('٢025-0٢-٢9', '%Y-%m-%d')
with self.assertRaises(ValueError): strptime('1٢:02:٢7', '%H:%M:%S')
with self.assertRaises(ValueError): strptime('٢5', '%y')
with self.assertRaises(ValueError): strptime('٢555', '%G')
with self.assertRaises(ValueError): strptime('٢/0٢ 0٢a٢', '%j/%y %I%p:%M:%S')
with self.assertRaises(ValueError): strptime('0٢/٢/200٢', '%U/%V')

def test_strptime_single_digit(self):
# bpo-34903: Check that single digit dates and times are allowed.

Expand Down Expand Up @@ -4070,7 +4078,7 @@ def test_strptime_tz(self):
self.assertEqual(strptime("UTC", "%Z").tzinfo, None)

def test_strptime_errors(self):
for tzstr in ("-2400", "-000", "z"):
for tzstr in ("-2400", "-000", "z", "٢"):
with self.assertRaises(ValueError):
self.theclass.strptime(tzstr, "%z")

Expand Down
4 changes: 4 additions & 0 deletions Lib/test/test_time.py
Original file line number Diff line number Diff line change
Expand Up @@ -357,6 +357,10 @@ def test_strptime_leap_year(self):
r'.*day of month without a year.*'):
time.strptime('02-07 18:28', '%m-%d %H:%M')

def test_strptime_non_ascii(self):
with self.assertRaises(ValueError):
time.strptime('٢025', '%Y')

def test_asctime(self):
time.asctime(time.gmtime(self.t))

Expand Down
Original file line number Diff line number Diff line change
@@ -0,0 +1,3 @@
Digits passed to :meth:`datetime.date.strptime`, :meth:`datetime.datetime.strptime`,
:meth:`datetime.time.strptime` and :meth:`time.strptime` must now be ASCII in
non-locale-specific numeric format codes.
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