Pure Python strptime implementation by Brett Cannon. See SF patch 474274.
Also adds tests.
diff --git a/Lib/_strptime.py b/Lib/_strptime.py
new file mode 100644
index 0000000..cde6e5f
--- /dev/null
+++ b/Lib/_strptime.py
@@ -0,0 +1,488 @@
+"""Strptime-related classes and functions.
+
+CLASSES:
+ LocaleTime -- Discovers and/or stores locale-specific time information
+ TimeRE -- Creates regexes for pattern matching string of text containing
+ time information as is returned by time.strftime()
+
+FUNCTIONS:
+ firstjulian -- Calculates the Julian date up to the first of the specified
+ year
+ gregorian -- Calculates the Gregorian date based on the Julian day and
+ year
+ julianday -- Calculates the Julian day since the first of the year based
+ on the Gregorian date
+ dayofweek -- Calculates the day of the week from the Gregorian date.
+ strptime -- Calculates the time struct represented by the passed-in string
+
+Requires Python 2.2.1 or higher.
+Can be used in Python 2.2 if the following line is added:
+ >>> True = 1; False = 0
+
+"""
+import time
+import locale
+import calendar
+from re import compile as re_compile
+from re import IGNORECASE
+from string import whitespace as whitespace_string
+
+__version__ = (2,1,5)
+__author__ = "Brett Cannon"
+__email__ = "drifty@bigfoot.com"
+
+__all__ = ['strptime']
+
+class LocaleTime(object):
+ """Stores and handles locale-specific information related to time.
+
+ ATTRIBUTES (all read-only after instance creation! Instance variables that
+ store the values have mangled names):
+ f_weekday -- full weekday names (7-item list)
+ a_weekday -- abbreviated weekday names (7-item list)
+ f_month -- full weekday names (14-item list; dummy value in [0], which
+ is added by code)
+ a_month -- abbreviated weekday names (13-item list, dummy value in
+ [0], which is added by code)
+ am_pm -- AM/PM representation (2-item list)
+ LC_date_time -- format string for date/time representation (string)
+ LC_date -- format string for date representation (string)
+ LC_time -- format string for time representation (string)
+ timezone -- daylight- and non-daylight-savings timezone representation
+ (3-item list; code tacks on blank item at end for
+ possible lack of timezone such as UTC)
+ lang -- Language used by instance (string)
+
+ """
+
+ def __init__(self, f_weekday=None, a_weekday=None, f_month=None,
+ a_month=None, am_pm=None, LC_date_time=None, LC_time=None, LC_date=None,
+ timezone=None, lang=None):
+ """Optionally set attributes with passed-in values."""
+ if f_weekday is None: self.__f_weekday = None
+ elif len(f_weekday) == 7: self.__f_weekday = list(f_weekday)
+ else:
+ raise TypeError("full weekday names must be a 7-item sequence")
+ if a_weekday is None: self.__a_weekday = None
+ elif len(a_weekday) == 7: self.__a_weekday = list(a_weekday)
+ else:
+ raise TypeError(
+ "abbreviated weekday names must be a 7-item sequence")
+ if f_month is None: self.__f_month = None
+ elif len(f_month) == 12:
+ self.__f_month = self.__pad(f_month, True)
+ else:
+ raise TypeError("full month names must be a 12-item sequence")
+ if a_month is None: self.__a_month = None
+ elif len(a_month) == 12:
+ self.__a_month = self.__pad(a_month, True)
+ else:
+ raise TypeError(
+ "abbreviated month names must be a 12-item sequence")
+ if am_pm is None:
+ self.__am_pm = None
+ elif len(am_pm) == 2:
+ self.__am_pm = am_pm
+ else:
+ raise TypeError("AM/PM representation must be a 2-item sequence")
+ self.__LC_date_time = LC_date_time
+ self.__LC_time = LC_time
+ self.__LC_date = LC_date
+ self.__timezone = timezone
+ if timezone:
+ if len(timezone) != 2:
+ raise TypeError("timezone names must contain 2 items")
+ else:
+ self.__timezone = self.__pad(timezone, False)
+ self.__lang = lang
+
+ def __pad(self, seq, front):
+ """Add '' to seq to either front (is True), else the back."""
+ seq = list(seq)
+ if front: seq.insert(0, '')
+ else: seq.append('')
+ return seq
+
+ def __set_nothing(self, stuff):
+ """Raise TypeError when trying to set an attribute."""
+ raise TypeError("attribute does not support assignment")
+
+ def __get_f_weekday(self):
+ """Fetch self.f_weekday."""
+ if not self.__f_weekday: self.__calc_weekday()
+ return self.__f_weekday
+
+ def __get_a_weekday(self):
+ """Fetch self.a_weekday."""
+ if not self.__a_weekday: self.__calc_weekday()
+ return self.__a_weekday
+
+ f_weekday = property(__get_f_weekday, __set_nothing,
+ doc="Full weekday names")
+ a_weekday = property(__get_a_weekday, __set_nothing,
+ doc="Abbreviated weekday names")
+
+ def __get_f_month(self):
+ """Fetch self.f_month."""
+ if not self.__f_month: self.__calc_month()
+ return self.__f_month
+
+ def __get_a_month(self):
+ """Fetch self.a_month."""
+ if not self.__a_month: self.__calc_month()
+ return self.__a_month
+
+ f_month = property(__get_f_month, __set_nothing,
+ doc="Full month names (dummy value at index 0)")
+ a_month = property(__get_a_month, __set_nothing,
+ doc="Abbreviated month names (dummy value at index 0)")
+
+ def __get_am_pm(self):
+ """Fetch self.am_pm."""
+ if not self.__am_pm: self.__calc_am_pm()
+ return self.__am_pm
+
+ am_pm = property(__get_am_pm, __set_nothing, doc="AM/PM representation")
+
+ def __get_timezone(self):
+ """Fetch self.timezone."""
+ if not self.__timezone: self.__calc_timezone()
+ return self.__timezone
+
+ timezone = property(__get_timezone, __set_nothing,
+ doc="Timezone representation (dummy value at index 2)")
+
+ def __get_LC_date_time(self):
+ """Fetch self.LC_date_time."""
+ if not self.__LC_date_time: self.__calc_date_time()
+ return self.__LC_date_time
+
+ def __get_LC_date(self):
+ """Fetch self.LC_date."""
+ if not self.__LC_date: self.__calc_date_time()
+ return self.__LC_date
+
+ def __get_LC_time(self):
+ """Fetch self.LC_time."""
+ if not self.__LC_time: self.__calc_date_time()
+ return self.__LC_time
+
+ LC_date_time = property(__get_LC_date_time, __set_nothing,
+ doc="Format string for locale's date/time representation ('%c' format)")
+ LC_date = property(__get_LC_date, __set_nothing,
+ doc="Format string for locale's date representation ('%x' format)")
+ LC_time = property(__get_LC_time, __set_nothing,
+ doc="Format string for locale's time representation ('%X' format)")
+
+ def __get_lang(self):
+ """Fetch self.lang."""
+ if not self.__lang: self.__calc_lang()
+ return self.__lang
+
+ lang = property(__get_lang, __set_nothing, doc="Language used for instance")
+
+ def __calc_weekday(self):
+ """Set self.__a_weekday and self.__f_weekday using the calendar module."""
+ a_weekday = [calendar.day_abbr[i] for i in range(7)]
+ f_weekday = [calendar.day_name[i] for i in range(7)]
+ if not self.__a_weekday: self.__a_weekday = a_weekday
+ if not self.__f_weekday: self.__f_weekday = f_weekday
+
+ def __calc_month(self):
+ """Set self.__f_month and self.__a_month using the calendar module."""
+ a_month = [calendar.month_abbr[i] for i in range(13)]
+ f_month = [calendar.month_name[i] for i in range(13)]
+ if not self.__a_month: self.__a_month = a_month
+ if not self.__f_month: self.__f_month = f_month
+
+ def __calc_am_pm(self):
+ """Set self.__am_pm by using time.strftime().
+
+ The magic date (2002, 3, 17, hour, 44, 44, 2, 76, 0) is not really
+ that magical; just happened to have used it everywhere else where a
+ static date was needed.
+
+ """
+ am_pm = []
+ for hour in (01,22):
+ time_tuple = time.struct_time((1999,3,17,hour,44,55,2,76,0))
+ am_pm.append(time.strftime("%p", time_tuple))
+ self.__am_pm = am_pm
+
+ def __calc_date_time(self):
+ """Set self.__date_time, self.__date, & self.__time by using time.strftime().
+
+ Use (1999,3,17,22,44,55,2,76,0) for magic date because the amount of
+ overloaded numbers is minimized. The order in which searches for
+ values within the format string is very important; it eliminates
+ possible ambiguity for what something represents.
+
+ """
+ time_tuple = time.struct_time((1999,3,17,22,44,55,2,76,0))
+ date_time = [None, None, None]
+ date_time[0] = time.strftime("%c", time_tuple)
+ date_time[1] = time.strftime("%x", time_tuple)
+ date_time[2] = time.strftime("%X", time_tuple)
+ for offset,directive in ((0,'%c'), (1,'%x'), (2,'%X')):
+ current_format = date_time[offset]
+ current_format = current_format.replace('%', '%%')
+ current_format = current_format.replace(self.f_weekday[2], '%A')
+ current_format = current_format.replace(self.f_month[3], '%B')
+ current_format = current_format.replace(self.a_weekday[2], '%a')
+ current_format = current_format.replace(self.a_month[3], '%b')
+ current_format = current_format.replace(self.am_pm[1], '%p')
+ current_format = current_format.replace(self.timezone[0], '%Z')
+ current_format = current_format.replace(self.timezone[1], '%Z')
+ current_format = current_format.replace('1999', '%Y')
+ current_format = current_format.replace('99', '%y')
+ current_format = current_format.replace('22', '%H')
+ current_format = current_format.replace('44', '%M')
+ current_format = current_format.replace('55', '%S')
+ current_format = current_format.replace('76', '%j')
+ current_format = current_format.replace('17', '%d')
+ current_format = current_format.replace('03', '%m')
+ current_format = current_format.replace('2', '%w')
+ current_format = current_format.replace('10', '%I')
+ time_tuple = time.struct_time((1999,1,3,1,1,1,6,3,0))
+ if time.strftime(directive, time_tuple).find('00'):
+ U_W = '%U'
+ else:
+ U_W = '%W'
+ date_time[offset] = current_format.replace('11', U_W)
+ if not self.__LC_date_time: self.__LC_date_time = date_time[0]
+ if not self.__LC_date: self.__LC_date = date_time[1]
+ if not self.__LC_time: self.__LC_time = date_time[2]
+
+ def __calc_timezone(self):
+ """Set self.__timezone by using time.tzname.
+
+ Empty string used for matching when timezone is not used/needed such
+ as with UTC.
+
+ """
+ self.__timezone = self.__pad(time.tzname, 0)
+
+ def __calc_lang(self):
+ """Set self.lang by using locale.getlocale() or
+ locale.getdefaultlocale().
+
+ """
+ current_lang = locale.getlocale(locale.LC_TIME)[0]
+ if current_lang: self.__lang = current_lang
+ else: self.__lang = locale.getdefaultlocale()[0]
+
+class TimeRE(dict):
+ """Handle conversion from format directives to regexes."""
+
+ def __init__(self, locale_time=LocaleTime()):
+ """Initialize instance with non-locale regexes and store LocaleTime object."""
+ super(TimeRE,self).__init__({
+ 'd': r"(?P<d>3[0-1]|[0-2]\d|\d| \d)", #The " \d" option is
+ #to make %c from ANSI
+ #C work
+ 'H': r"(?P<H>2[0-3]|[0-1]\d|\d)",
+ 'I': r"(?P<I>0\d|1[0-2]|\d)",
+ 'j': r"(?P<j>(?:3[0-5]\d|6[0-6])|[0-2]\d\d|\d)",
+ 'm': r"(?P<m>0\d|1[0-2]|\d)",
+ '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)",
+ 'w': r"(?P<w>[0-6])",
+ 'W': r"(?P<W>5[0-3]|[0-4]\d|\d)", #Same as U
+ 'y': r"(?P<y>\d\d)",
+ 'Y': r"(?P<Y>\d\d\d\d)"})
+ self.locale_time = locale_time
+
+ def __getitem__(self, fetch):
+ """Try to fetch regex; if it does not exist, construct it."""
+ try:
+ return super(TimeRE,self).__getitem__(fetch)
+ except KeyError:
+ if fetch == 'A':
+ self[fetch] = self.__seqToRE(self.locale_time.f_weekday,
+ fetch)
+ elif fetch == 'a':
+ self[fetch] = self.__seqToRE(self.locale_time.a_weekday,
+ fetch)
+ elif fetch == 'B':
+ self[fetch] = self.__seqToRE(self.locale_time.f_month[1:],
+ fetch)
+ elif fetch == 'b':
+ self[fetch] = self.__seqToRE(self.locale_time.a_month[1:],
+ fetch)
+ elif fetch == 'c':
+ self[fetch] = self.pattern(self.locale_time.LC_date_time)
+ elif fetch == 'p':
+ self[fetch] = self.__seqToRE(self.locale_time.am_pm, fetch)
+ elif fetch == 'x':
+ self[fetch] = self.pattern(self.locale_time.LC_date)
+ elif fetch == 'X':
+ self[fetch] = self.pattern(self.locale_time.LC_time)
+ elif fetch == 'Z':
+ self[fetch] = self.__seqToRE(self.locale_time.timezone,
+ fetch)
+ elif fetch == '%':
+ return '%'
+ return super(TimeRE,self).__getitem__(fetch)
+
+ def __seqToRE(self, to_convert, directive):
+ """Convert a list to a regex string for matching directive."""
+ def sorter(a, b):
+ """Sort based on length.
+
+ Done in case for some strange reason that names in the locale only
+ differ by a suffix and thus want the name with the suffix to match
+ first.
+
+ """
+ try: a_length = len(a)
+ except TypeError: a_length = 0
+ try: b_length = len(b)
+ except TypeError: b_length = 0
+ return cmp(b_length, a_length)
+
+ to_convert = to_convert[:] #Don't want to change value in-place.
+ to_convert.sort(sorter)
+ regex = '(?P<%s>' % directive
+ for item in to_convert:
+ regex = "%s(?:%s)|" % (regex, item)
+ else:
+ regex = regex[:-1]
+ return '%s)' % regex
+
+ def pattern(self, format):
+ """Return re pattern for the format string."""
+ processed_format = ''
+ for whitespace in whitespace_string:
+ format = format.replace(whitespace, r'\s*')
+ while format.find('%') != -1:
+ directive_index = format.index('%')+1
+ processed_format = "%s%s%s" % (processed_format,
+ format[:directive_index-1],
+ self[format[directive_index]])
+ format = format[directive_index+1:]
+ return "%s%s" % (processed_format, format)
+
+ def compile(self, format):
+ """Return a compiled re object for the format string."""
+ format = "(?#%s)%s" % (self.locale_time.lang,format)
+ return re_compile(self.pattern(format), IGNORECASE)
+
+
+def strptime(data_string, format="%a %b %d %H:%M:%S %Y"):
+ """Convert data_string to a time struct based on the format string or re object; will return an re object for format if data_string is False.
+
+ The object passed in for format may either be a re object compiled by
+ strptime() or a format string. If False is passed in for data_string
+ then an re object for format will be returned. The re object
+ must be used with the same language as used to compile the re object.
+
+ """
+ locale_time = LocaleTime()
+ if isinstance(format, type(re_compile(''))):
+ if format.pattern.find(locale_time.lang) == -1:
+ raise TypeError("re object not created with same language as \
+ LocaleTime instance")
+ else:
+ compiled_re = format
+ else:
+ compiled_re = TimeRE(locale_time).compile(format)
+ if data_string is False:
+ return compiled_re
+ else:
+ found = compiled_re.match(data_string)
+ if not found:
+ raise ValueError("time data did not match format")
+ year = month = day = hour = minute = second = weekday = julian = tz = -1
+ found_dict = found.groupdict()
+ for group_key in found_dict.iterkeys():
+ if group_key in 'yY':
+ if group_key is 'y':
+ year = int("%s%s" % (time.strftime("%Y")[:-2], found_dict['y']))
+ else:
+ year = int(found_dict['Y'])
+ elif group_key in 'Bbm':
+ if group_key is 'm':
+ month = int(found_dict['m'])
+ elif group_key is 'B':
+ month = locale_time.f_month.index(found_dict['B'])
+ else:
+ month = locale_time.a_month.index(found_dict['b'])
+ elif group_key is 'd':
+ day = int(found_dict['d'])
+ elif group_key in 'HI':
+ if group_key is 'H':
+ hour = int(found_dict['H'])
+ else:
+ hour = int(found_dict['I'])
+ if found_dict.has_key('p'):
+ if found_dict['p'] == locale_time.am_pm[1]:
+ hour += 12
+ else:
+ if hour is 12:
+ hour = 0
+ elif group_key is 'M':
+ minute = int(found_dict['M'])
+ elif group_key is 'S':
+ second = int(found_dict['S'])
+ elif group_key in 'Aaw':
+ if group_key is 'A':
+ weekday = locale_time.f_weekday.index(found_dict['A'])
+ elif group_key is 'a':
+ weekday = locale_time.a_weekday.index(found_dict['a'])
+ else:
+ weekday = int(found_dict['w'])
+ if weekday == 0:
+ weekday = 6
+ else:
+ weekday -= 1
+ elif group_key is 'j':
+ julian = int(found_dict['j'])
+ elif group_key is 'Z':
+ if locale_time.timezone[0] == found_dict['Z']:
+ tz = 0
+ elif locale_time.timezone[1] == found_dict['Z']:
+ tz = 1
+ elif locale_time.timezone[2] == found_dict['Z']:
+ tz = 0
+ if julian == -1 and year != -1 and month != -1 and day != -1:
+ julian = julianday(year, month, day)
+ if (month == -1 or day == -1) and julian != -1 and year != -1:
+ year,month,day = gregorian(julian, year)
+ if weekday == -1 and year != -1 and month != -1 and day != -1:
+ weekday = dayofweek(year, month, day)
+ return time.struct_time((year,month,day,hour,minute,second,weekday,
+ julian,tz))
+
+def firstjulian(year):
+ """Calculate the Julian date up until the first of the year."""
+ return ((146097*(year+4799))//400)-31738
+
+def julianday(year, month, day):
+ """Calculate the Julian day since the beginning of the year from the Gregorian date."""
+ a = (14-month)//12
+ return (day-32045+(((153*(month+(12*a)-3))+2)//5)+\
+ ((146097*(year+4800-a))//400))-firstjulian(year)+1
+
+def gregorian(julian, year):
+ """Return a 3-item list containing the Gregorian date based on the Julian day."""
+ a = 32043+julian+firstjulian(year)
+ b = ((4*a)+3)//146097
+ c = a-((146097*b)//4)
+ d = ((4*c)+3)//1461
+ e = c-((1461*d)//4)
+ m = ((5*e)+2)//153
+ day = 1+e-(((153*m)+2)//5)
+ month = m+3-(12*(m//10))
+ year = (100*b)+d-4800+(m//10)
+ return [year, month, day]
+
+def dayofweek(year, month, day):
+ """Calculate the day of the week (Monday is 0)."""
+ a = (14-month)//12
+ y = year-a
+ weekday = (day+y+((97*y)//400)+((31*(month+(12*a)-2))//12))%7
+ if weekday == 0:
+ return 6
+ else:
+ return weekday-1