diff options
Diffstat (limited to 'Lib/_pydatetime.py')
| -rw-r--r-- | Lib/_pydatetime.py | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/Lib/_pydatetime.py b/Lib/_pydatetime.py index 27cacb8..78432d4 100644 --- a/Lib/_pydatetime.py +++ b/Lib/_pydatetime.py @@ -215,6 +215,17 @@ def _need_normalize_century(): _normalize_century = True return _normalize_century +_supports_c99 = None +def _can_support_c99(): + global _supports_c99 + if _supports_c99 is None: + try: + _supports_c99 = ( + _time.strftime("%F", (1900, 1, 1, 0, 0, 0, 0, 1, 0)) == "1900-01-01") + except ValueError: + _supports_c99 = False + return _supports_c99 + # Correctly substitute for %z and %Z escapes in strftime formats. def _wrap_strftime(object, format, timetuple): # Don't call utcoffset() or tzname() unless actually needed. @@ -272,14 +283,20 @@ def _wrap_strftime(object, format, timetuple): # strftime is going to have at this: escape % Zreplace = s.replace('%', '%%') newformat.append(Zreplace) - elif ch in 'YG' and object.year < 1000 and _need_normalize_century(): - # Note that datetime(1000, 1, 1).strftime('%G') == '1000' so - # year 1000 for %G can go on the fast path. + # Note that datetime(1000, 1, 1).strftime('%G') == '1000' so + # year 1000 for %G can go on the fast path. + elif ((ch in 'YG' or ch in 'FC' and _can_support_c99()) and + object.year < 1000 and _need_normalize_century()): if ch == 'G': year = int(_time.strftime("%G", timetuple)) else: year = object.year - push('{:04}'.format(year)) + if ch == 'C': + push('{:02}'.format(year // 100)) + else: + push('{:04}'.format(year)) + if ch == 'F': + push('-{:02}-{:02}'.format(*timetuple[1:3])) else: push('%') push(ch) |