diff --git a/Lib/_pydatetime.py b/Lib/_pydatetime.py index c47f4e671b39de..9b6e74a8fc50dd 100644 --- a/Lib/_pydatetime.py +++ b/Lib/_pydatetime.py @@ -355,19 +355,30 @@ def _find_isoformat_datetime_separator(dtstr): return 8 +def _read_isoformat_component(s, n): + # The caller has verified the string is ASCII, so isdigit() matches only + # the ASCII digits accepted by the C parser. + if len(s) != n or not s.isdigit(): + raise ValueError("Invalid isoformat string") + return int(s) + + def _parse_isoformat_date(dtstr): # It is assumed that this is an ASCII-only string of lengths 7, 8 or 10, # see the comment on Modules/_datetimemodule.c:_find_isoformat_datetime_separator if len(dtstr) not in (7, 8, 10): raise ValueError("Invalid isoformat string") - year = int(dtstr[0:4]) + if not dtstr.isascii(): + raise ValueError("Invalid isoformat string") + + year = _read_isoformat_component(dtstr[0:4], 4) has_sep = dtstr[4] == '-' pos = 4 + has_sep if dtstr[pos:pos + 1] == "W": # YYYY-?Www-?D? pos += 1 - weekno = int(dtstr[pos:pos + 2]) + weekno = _read_isoformat_component(dtstr[pos:pos + 2], 2) pos += 2 dayno = 1 @@ -377,17 +388,17 @@ def _parse_isoformat_date(dtstr): pos += has_sep - dayno = int(dtstr[pos:pos + 1]) + dayno = _read_isoformat_component(dtstr[pos:pos + 1], 1) return list(_isoweek_to_gregorian(year, weekno, dayno)) else: - month = int(dtstr[pos:pos + 2]) + month = _read_isoformat_component(dtstr[pos:pos + 2], 2) pos += 2 if (dtstr[pos:pos + 1] == "-") != has_sep: raise ValueError("Inconsistent use of dash separator") pos += has_sep - day = int(dtstr[pos:pos + 2]) + day = _read_isoformat_component(dtstr[pos:pos + 2], 2) return [year, month, day] @@ -405,7 +416,7 @@ def _parse_hh_mm_ss_ff(tstr): if (len_str - pos) < 2: raise ValueError("Incomplete time component") - time_comps[comp] = int(tstr[pos:pos+2]) + time_comps[comp] = _read_isoformat_component(tstr[pos:pos+2], 2) pos += 2 next_char = tstr[pos:pos+1] @@ -447,6 +458,8 @@ def _parse_isoformat_time(tstr): len_str = len(tstr) if len_str < 2: raise ValueError("Isoformat time too short") + if not tstr.isascii(): + raise ValueError("Invalid isoformat string") # This is equivalent to re.search('[+-Z]', tstr), but faster tz_pos = (tstr.find('-') + 1 or tstr.find('+') + 1 or tstr.find('Z') + 1) diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py index c11e9c068bed3b..dcd8db9fa2c2c9 100644 --- a/Lib/test/datetimetester.py +++ b/Lib/test/datetimetester.py @@ -2106,7 +2106,15 @@ def test_fromisoformat_fails(self): '10000-W25-1', # Invalid year '2020-W25-0', # Invalid day-of-week '2020-W25-8', # Invalid day-of-week - '٢025-03-09' # Unicode characters + # gh-152204: each fixed-width field must be exactly N ASCII digits + '2020+12', # '+' accepted in a basic-format field + '2020 12', # space accepted in a basic-format field + '+020-06-15', # leading sign in the year + '202012+9', # '+' in the day field + '2020-W 5', # space in the week day-of-week field + '2020061', # 7 chars: day slice reads a 1-character tail + '2020-W2', # 1-digit week number + '٢025-03-09', # Unicode characters '2009\ud80002\ud80028', # Separators are surrogate codepoints ] @@ -3758,10 +3766,9 @@ def test_fromisoformat_fails_datetime(self): '2009-04-19T12:30:45-00:90:00', # Time zone field out from range '2009-04-19T12:30:45-00:00:90', # Time zone field out from range '2020-2020', # Ambiguous 9-char date portion - '2009-04-19T12:30:45.+05:00', # Empty fraction before offset - '2009-04-19T12:30:45.-05:00', # Empty fraction before offset - '2009-04-19T12:30:45.Z', # Empty fraction before Z - '2009-04-19T12:30:45,+05:00', # Empty fraction (comma) before offset + '2009-04-19T12:30:4٥', # Unicode digit in the seconds + '20201212T0102٣٤', # Unicode digits in the time (gh-152204) + '2009-04-19T12:30:45+0٥:00', # Unicode digit in the timezone ] for bad_str in bad_strs: @@ -4123,11 +4130,6 @@ def test_strftime_special(self): self.assertEqual(t.strftime('\0'*1000), '\0'*1000) self.assertEqual(t.strftime('\0%I%p%Z\0%X'), f'\0{s1}\0{s2}') self.assertEqual(t.strftime('%I%p%Z\0%X\0'), f'{s1}\0{s2}\0') - # gh-152305: the year directives must not raise on a time. - for directive, expected in (('%Y', '1900'), ('%G', '1900'), - ('%C', '19'), ('%F', '1900-01-01')): - with self.subTest(directive=directive): - self.assertEqual(t.strftime(directive), expected) def test_format(self): t = self.theclass(1, 2, 3, 4) @@ -5038,10 +5040,6 @@ def test_fromisoformat_fails(self): '24:01:00.000000', # Has non-zero minutes on 24:00 '12:30:45+00:90:00', # Time zone field out from range '12:30:45+00:00:90', # Time zone field out from range - '12:30:45.+05:00', # Empty fraction before offset - '12:30:45.-05:00', # Empty fraction before offset - '12:30:45.Z', # Empty fraction before Z - '12:30:45,+05:00', # Empty fraction (comma) before offset ] for bad_str in bad_strs: diff --git a/Misc/NEWS.d/next/Library/2026-06-25-14-05-00.gh-issue-152204.k9Qm3v.rst b/Misc/NEWS.d/next/Library/2026-06-25-14-05-00.gh-issue-152204.k9Qm3v.rst new file mode 100644 index 00000000000000..1ba1f872eb41a6 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-06-25-14-05-00.gh-issue-152204.k9Qm3v.rst @@ -0,0 +1,6 @@ +Fix the pure-Python implementations of :meth:`datetime.date.fromisoformat`, +:meth:`datetime.time.fromisoformat` and :meth:`datetime.datetime.fromisoformat` +silently accepting some malformed ISO 8601 strings, such as non-ASCII digits or +a sign in a fixed-width field (for example ``'2020+12'`` or ``'20201212T0102٣٤'``). +Each field is now required to be exactly *N* ASCII digits, matching the C +implementation.