| """Concrete date/time and related types. |
| |
| See http://www.iana.org/time-zones/repository/tz-link.html for |
| time zone and DST data sources. |
| """ |
| |
| import time as _time |
| import math as _math |
| |
| def _cmp(x, y): |
| return 0 if x == y else 1 if x > y else -1 |
| |
| MINYEAR = 1 |
| MAXYEAR = 9999 |
| _MAXORDINAL = 3652059 # date.max.toordinal() |
| |
| # Utility functions, adapted from Python's Demo/classes/Dates.py, which |
| # also assumes the current Gregorian calendar indefinitely extended in |
| # both directions. Difference: Dates.py calls January 1 of year 0 day |
| # number 1. The code here calls January 1 of year 1 day number 1. This is |
| # to match the definition of the "proleptic Gregorian" calendar in Dershowitz |
| # and Reingold's "Calendrical Calculations", where it's the base calendar |
| # for all computations. See the book for algorithms for converting between |
| # proleptic Gregorian ordinals and many other calendar systems. |
| |
| # -1 is a placeholder for indexing purposes. |
| _DAYS_IN_MONTH = [-1, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31] |
| |
| _DAYS_BEFORE_MONTH = [-1] # -1 is a placeholder for indexing purposes. |
| dbm = 0 |
| for dim in _DAYS_IN_MONTH[1:]: |
| _DAYS_BEFORE_MONTH.append(dbm) |
| dbm += dim |
| del dbm, dim |
| |
| def _is_leap(year): |
| "year -> 1 if leap year, else 0." |
| return year % 4 == 0 and (year % 100 != 0 or year % 400 == 0) |
| |
| def _days_before_year(year): |
| "year -> number of days before January 1st of year." |
| y = year - 1 |
| return y*365 + y//4 - y//100 + y//400 |
| |
| def _days_in_month(year, month): |
| "year, month -> number of days in that month in that year." |
| assert 1 <= month <= 12, month |
| if month == 2 and _is_leap(year): |
| return 29 |
| return _DAYS_IN_MONTH[month] |
| |
| def _days_before_month(year, month): |
| "year, month -> number of days in year preceding first day of month." |
| assert 1 <= month <= 12, 'month must be in 1..12' |
| return _DAYS_BEFORE_MONTH[month] + (month > 2 and _is_leap(year)) |
| |
| def _ymd2ord(year, month, day): |
| "year, month, day -> ordinal, considering 01-Jan-0001 as day 1." |
| assert 1 <= month <= 12, 'month must be in 1..12' |
| dim = _days_in_month(year, month) |
| assert 1 <= day <= dim, ('day must be in 1..%d' % dim) |
| return (_days_before_year(year) + |
| _days_before_month(year, month) + |
| day) |
| |
| _DI400Y = _days_before_year(401) # number of days in 400 years |
| _DI100Y = _days_before_year(101) # " " " " 100 " |
| _DI4Y = _days_before_year(5) # " " " " 4 " |
| |
| # A 4-year cycle has an extra leap day over what we'd get from pasting |
| # together 4 single years. |
| assert _DI4Y == 4 * 365 + 1 |
| |
| # Similarly, a 400-year cycle has an extra leap day over what we'd get from |
| # pasting together 4 100-year cycles. |
| assert _DI400Y == 4 * _DI100Y + 1 |
| |
| # OTOH, a 100-year cycle has one fewer leap day than we'd get from |
| # pasting together 25 4-year cycles. |
| assert _DI100Y == 25 * _DI4Y - 1 |
| |
| def _ord2ymd(n): |
| "ordinal -> (year, month, day), considering 01-Jan-0001 as day 1." |
| |
| # n is a 1-based index, starting at 1-Jan-1. The pattern of leap years |
| # repeats exactly every 400 years. The basic strategy is to find the |
| # closest 400-year boundary at or before n, then work with the offset |
| # from that boundary to n. Life is much clearer if we subtract 1 from |
| # n first -- then the values of n at 400-year boundaries are exactly |
| # those divisible by _DI400Y: |
| # |
| # D M Y n n-1 |
| # -- --- ---- ---------- ---------------- |
| # 31 Dec -400 -_DI400Y -_DI400Y -1 |
| # 1 Jan -399 -_DI400Y +1 -_DI400Y 400-year boundary |
| # ... |
| # 30 Dec 000 -1 -2 |
| # 31 Dec 000 0 -1 |
| # 1 Jan 001 1 0 400-year boundary |
| # 2 Jan 001 2 1 |
| # 3 Jan 001 3 2 |
| # ... |
| # 31 Dec 400 _DI400Y _DI400Y -1 |
| # 1 Jan 401 _DI400Y +1 _DI400Y 400-year boundary |
| n -= 1 |
| n400, n = divmod(n, _DI400Y) |
| year = n400 * 400 + 1 # ..., -399, 1, 401, ... |
| |
| # Now n is the (non-negative) offset, in days, from January 1 of year, to |
| # the desired date. Now compute how many 100-year cycles precede n. |
| # Note that it's possible for n100 to equal 4! In that case 4 full |
| # 100-year cycles precede the desired day, which implies the desired |
| # day is December 31 at the end of a 400-year cycle. |
| n100, n = divmod(n, _DI100Y) |
| |
| # Now compute how many 4-year cycles precede it. |
| n4, n = divmod(n, _DI4Y) |
| |
| # And now how many single years. Again n1 can be 4, and again meaning |
| # that the desired day is December 31 at the end of the 4-year cycle. |
| n1, n = divmod(n, 365) |
| |
| year += n100 * 100 + n4 * 4 + n1 |
| if n1 == 4 or n100 == 4: |
| assert n == 0 |
| return year-1, 12, 31 |
| |
| # Now the year is correct, and n is the offset from January 1. We find |
| # the month via an estimate that's either exact or one too large. |
| leapyear = n1 == 3 and (n4 != 24 or n100 == 3) |
| assert leapyear == _is_leap(year) |
| month = (n + 50) >> 5 |
| preceding = _DAYS_BEFORE_MONTH[month] + (month > 2 and leapyear) |
| if preceding > n: # estimate is too large |
| month -= 1 |
| preceding -= _DAYS_IN_MONTH[month] + (month == 2 and leapyear) |
| n -= preceding |
| assert 0 <= n < _days_in_month(year, month) |
| |
| # Now the year and month are correct, and n is the offset from the |
| # start of that month: we're done! |
| return year, month, n+1 |
| |
| # Month and day names. For localized versions, see the calendar module. |
| _MONTHNAMES = [None, "Jan", "Feb", "Mar", "Apr", "May", "Jun", |
| "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"] |
| _DAYNAMES = [None, "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"] |
| |
| |
| def _build_struct_time(y, m, d, hh, mm, ss, dstflag): |
| wday = (_ymd2ord(y, m, d) + 6) % 7 |
| dnum = _days_before_month(y, m) + d |
| return _time.struct_time((y, m, d, hh, mm, ss, wday, dnum, dstflag)) |
| |
| def _format_time(hh, mm, ss, us, timespec='auto'): |
| specs = { |
| 'hours': '{:02d}', |
| 'minutes': '{:02d}:{:02d}', |
| 'seconds': '{:02d}:{:02d}:{:02d}', |
| 'milliseconds': '{:02d}:{:02d}:{:02d}.{:03d}', |
| 'microseconds': '{:02d}:{:02d}:{:02d}.{:06d}' |
| } |
| |
| if timespec == 'auto': |
| # Skip trailing microseconds when us==0. |
| timespec = 'microseconds' if us else 'seconds' |
| elif timespec == 'milliseconds': |
| us //= 1000 |
| try: |
| fmt = specs[timespec] |
| except KeyError: |
| raise ValueError('Unknown timespec value') |
| else: |
| return fmt.format(hh, mm, ss, us) |
| |
| def _format_offset(off): |
| s = '' |
| if off is not None: |
| if off.days < 0: |
| sign = "-" |
| off = -off |
| else: |
| sign = "+" |
| hh, mm = divmod(off, timedelta(hours=1)) |
| mm, ss = divmod(mm, timedelta(minutes=1)) |
| s += "%s%02d:%02d" % (sign, hh, mm) |
| if ss or ss.microseconds: |
| s += ":%02d" % ss.seconds |
| |
| if ss.microseconds: |
| s += '.%06d' % ss.microseconds |
| return s |
| |
| # 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. |
| freplace = None # the string to use for %f |
| zreplace = None # the string to use for %z |
| Zreplace = None # the string to use for %Z |
| |
| # Scan format for %z and %Z escapes, replacing as needed. |
| newformat = [] |
| push = newformat.append |
| i, n = 0, len(format) |
| while i < n: |
| ch = format[i] |
| i += 1 |
| if ch == '%': |
| if i < n: |
| ch = format[i] |
| i += 1 |
| if ch == 'f': |
| if freplace is None: |
| freplace = '%06d' % getattr(object, |
| 'microsecond', 0) |
| newformat.append(freplace) |
| elif ch == 'z': |
| if zreplace is None: |
| zreplace = "" |
| if hasattr(object, "utcoffset"): |
| offset = object.utcoffset() |
| if offset is not None: |
| sign = '+' |
| if offset.days < 0: |
| offset = -offset |
| sign = '-' |
| h, rest = divmod(offset, timedelta(hours=1)) |
| m, rest = divmod(rest, timedelta(minutes=1)) |
| s = rest.seconds |
| u = offset.microseconds |
| if u: |
| zreplace = '%c%02d%02d%02d.%06d' % (sign, h, m, s, u) |
| elif s: |
| zreplace = '%c%02d%02d%02d' % (sign, h, m, s) |
| else: |
| zreplace = '%c%02d%02d' % (sign, h, m) |
| assert '%' not in zreplace |
| newformat.append(zreplace) |
| elif ch == 'Z': |
| if Zreplace is None: |
| Zreplace = "" |
| if hasattr(object, "tzname"): |
| s = object.tzname() |
| if s is not None: |
| # strftime is going to have at this: escape % |
| Zreplace = s.replace('%', '%%') |
| newformat.append(Zreplace) |
| else: |
| push('%') |
| push(ch) |
| else: |
| push('%') |
| else: |
| push(ch) |
| newformat = "".join(newformat) |
| return _time.strftime(newformat, timetuple) |
| |
| # Helpers for parsing the result of isoformat() |
| def _parse_isoformat_date(dtstr): |
| # It is assumed that this function will only be called with a |
| # string of length exactly 10, and (though this is not used) ASCII-only |
| year = int(dtstr[0:4]) |
| if dtstr[4] != '-': |
| raise ValueError('Invalid date separator: %s' % dtstr[4]) |
| |
| month = int(dtstr[5:7]) |
| |
| if dtstr[7] != '-': |
| raise ValueError('Invalid date separator') |
| |
| day = int(dtstr[8:10]) |
| |
| return [year, month, day] |
| |
| def _parse_hh_mm_ss_ff(tstr): |
| # Parses things of the form HH[:MM[:SS[.fff[fff]]]] |
| len_str = len(tstr) |
| |
| time_comps = [0, 0, 0, 0] |
| pos = 0 |
| for comp in range(0, 3): |
| if (len_str - pos) < 2: |
| raise ValueError('Incomplete time component') |
| |
| time_comps[comp] = int(tstr[pos:pos+2]) |
| |
| pos += 2 |
| next_char = tstr[pos:pos+1] |
| |
| if not next_char or comp >= 2: |
| break |
| |
| if next_char != ':': |
| raise ValueError('Invalid time separator: %c' % next_char) |
| |
| pos += 1 |
| |
| if pos < len_str: |
| if tstr[pos] != '.': |
| raise ValueError('Invalid microsecond component') |
| else: |
| pos += 1 |
| |
| len_remainder = len_str - pos |
| if len_remainder not in (3, 6): |
| raise ValueError('Invalid microsecond component') |
| |
| time_comps[3] = int(tstr[pos:]) |
| if len_remainder == 3: |
| time_comps[3] *= 1000 |
| |
| return time_comps |
| |
| def _parse_isoformat_time(tstr): |
| # Format supported is HH[:MM[:SS[.fff[fff]]]][+HH:MM[:SS[.ffffff]]] |
| len_str = len(tstr) |
| if len_str < 2: |
| raise ValueError('Isoformat time too short') |
| |
| # This is equivalent to re.search('[+-]', tstr), but faster |
| tz_pos = (tstr.find('-') + 1 or tstr.find('+') + 1) |
| timestr = tstr[:tz_pos-1] if tz_pos > 0 else tstr |
| |
| time_comps = _parse_hh_mm_ss_ff(timestr) |
| |
| tzi = None |
| if tz_pos > 0: |
| tzstr = tstr[tz_pos:] |
| |
| # Valid time zone strings are: |
| # HH:MM len: 5 |
| # HH:MM:SS len: 8 |
| # HH:MM:SS.ffffff len: 15 |
| |
| if len(tzstr) not in (5, 8, 15): |
| raise ValueError('Malformed time zone string') |
| |
| tz_comps = _parse_hh_mm_ss_ff(tzstr) |
| if all(x == 0 for x in tz_comps): |
| tzi = timezone.utc |
| else: |
| tzsign = -1 if tstr[tz_pos - 1] == '-' else 1 |
| |
| td = timedelta(hours=tz_comps[0], minutes=tz_comps[1], |
| seconds=tz_comps[2], microseconds=tz_comps[3]) |
| |
| tzi = timezone(tzsign * td) |
| |
| time_comps.append(tzi) |
| |
| return time_comps |
| |
| |
| # Just raise TypeError if the arg isn't None or a string. |
| def _check_tzname(name): |
| if name is not None and not isinstance(name, str): |
| raise TypeError("tzinfo.tzname() must return None or string, " |
| "not '%s'" % type(name)) |
| |
| # name is the offset-producing method, "utcoffset" or "dst". |
| # offset is what it returned. |
| # If offset isn't None or timedelta, raises TypeError. |
| # If offset is None, returns None. |
| # Else offset is checked for being in range. |
| # If it is, its integer value is returned. Else ValueError is raised. |
| def _check_utc_offset(name, offset): |
| assert name in ("utcoffset", "dst") |
| if offset is None: |
| return |
| if not isinstance(offset, timedelta): |
| raise TypeError("tzinfo.%s() must return None " |
| "or timedelta, not '%s'" % (name, type(offset))) |
| if not -timedelta(1) < offset < timedelta(1): |
| raise ValueError("%s()=%s, must be strictly between " |
| "-timedelta(hours=24) and timedelta(hours=24)" % |
| (name, offset)) |
| |
| def _check_int_field(value): |
| if isinstance(value, int): |
| return value |
| if not isinstance(value, float): |
| try: |
| value = value.__int__() |
| except AttributeError: |
| pass |
| else: |
| if isinstance(value, int): |
| return value |
| raise TypeError('__int__ returned non-int (type %s)' % |
| type(value).__name__) |
| raise TypeError('an integer is required (got type %s)' % |
| type(value).__name__) |
| raise TypeError('integer argument expected, got float') |
| |
| def _check_date_fields(year, month, day): |
| year = _check_int_field(year) |
| month = _check_int_field(month) |
| day = _check_int_field(day) |
| if not MINYEAR <= year <= MAXYEAR: |
| raise ValueError('year must be in %d..%d' % (MINYEAR, MAXYEAR), year) |
| if not 1 <= month <= 12: |
| raise ValueError('month must be in 1..12', month) |
| dim = _days_in_month(year, month) |
| if not 1 <= day <= dim: |
| raise ValueError('day must be in 1..%d' % dim, day) |
| return year, month, day |
| |
| def _check_time_fields(hour, minute, second, microsecond, fold): |
| hour = _check_int_field(hour) |
| minute = _check_int_field(minute) |
| second = _check_int_field(second) |
| microsecond = _check_int_field(microsecond) |
| if not 0 <= hour <= 23: |
| raise ValueError('hour must be in 0..23', hour) |
| if not 0 <= minute <= 59: |
| raise ValueError('minute must be in 0..59', minute) |
| if not 0 <= second <= 59: |
| raise ValueError('second must be in 0..59', second) |
| if not 0 <= microsecond <= 999999: |
| raise ValueError('microsecond must be in 0..999999', microsecond) |
| if fold not in (0, 1): |
| raise ValueError('fold must be either 0 or 1', fold) |
| return hour, minute, second, microsecond, fold |
| |
| def _check_tzinfo_arg(tz): |
| if tz is not None and not isinstance(tz, tzinfo): |
| raise TypeError("tzinfo argument must be None or of a tzinfo subclass") |
| |
| def _cmperror(x, y): |
| raise TypeError("can't compare '%s' to '%s'" % ( |
| type(x).__name__, type(y).__name__)) |
| |
| def _divide_and_round(a, b): |
| """divide a by b and round result to the nearest integer |
| |
| When the ratio is exactly half-way between two integers, |
| the even integer is returned. |
| """ |
| # Based on the reference implementation for divmod_near |
| # in Objects/longobject.c. |
| q, r = divmod(a, b) |
| # round up if either r / b > 0.5, or r / b == 0.5 and q is odd. |
| # The expression r / b > 0.5 is equivalent to 2 * r > b if b is |
| # positive, 2 * r < b if b negative. |
| r *= 2 |
| greater_than_half = r > b if b > 0 else r < b |
| if greater_than_half or r == b and q % 2 == 1: |
| q += 1 |
| |
| return q |
| |
| |
| class timedelta: |
| """Represent the difference between two datetime objects. |
| |
| Supported operators: |
| |
| - add, subtract timedelta |
| - unary plus, minus, abs |
| - compare to timedelta |
| - multiply, divide by int |
| |
| In addition, datetime supports subtraction of two datetime objects |
| returning a timedelta, and addition or subtraction of a datetime |
| and a timedelta giving a datetime. |
| |
| Representation: (days, seconds, microseconds). Why? Because I |
| felt like it. |
| """ |
| __slots__ = '_days', '_seconds', '_microseconds', '_hashcode' |
| |
| def __new__(cls, days=0, seconds=0, microseconds=0, |
| milliseconds=0, minutes=0, hours=0, weeks=0): |
| # Doing this efficiently and accurately in C is going to be difficult |
| # and error-prone, due to ubiquitous overflow possibilities, and that |
| # C double doesn't have enough bits of precision to represent |
| # microseconds over 10K years faithfully. The code here tries to make |
| # explicit where go-fast assumptions can be relied on, in order to |
| # guide the C implementation; it's way more convoluted than speed- |
| # ignoring auto-overflow-to-long idiomatic Python could be. |
| |
| # XXX Check that all inputs are ints or floats. |
| |
| # Final values, all integer. |
| # s and us fit in 32-bit signed ints; d isn't bounded. |
| d = s = us = 0 |
| |
| # Normalize everything to days, seconds, microseconds. |
| days += weeks*7 |
| seconds += minutes*60 + hours*3600 |
| microseconds += milliseconds*1000 |
| |
| # Get rid of all fractions, and normalize s and us. |
| # Take a deep breath <wink>. |
| if isinstance(days, float): |
| dayfrac, days = _math.modf(days) |
| daysecondsfrac, daysecondswhole = _math.modf(dayfrac * (24.*3600.)) |
| assert daysecondswhole == int(daysecondswhole) # can't overflow |
| s = int(daysecondswhole) |
| assert days == int(days) |
| d = int(days) |
| else: |
| daysecondsfrac = 0.0 |
| d = days |
| assert isinstance(daysecondsfrac, float) |
| assert abs(daysecondsfrac) <= 1.0 |
| assert isinstance(d, int) |
| assert abs(s) <= 24 * 3600 |
| # days isn't referenced again before redefinition |
| |
| if isinstance(seconds, float): |
| secondsfrac, seconds = _math.modf(seconds) |
| assert seconds == int(seconds) |
| seconds = int(seconds) |
| secondsfrac += daysecondsfrac |
| assert abs(secondsfrac) <= 2.0 |
| else: |
| secondsfrac = daysecondsfrac |
| # daysecondsfrac isn't referenced again |
| assert isinstance(secondsfrac, float) |
| assert abs(secondsfrac) <= 2.0 |
| |
| assert isinstance(seconds, int) |
| days, seconds = divmod(seconds, 24*3600) |
| d += days |
| s += int(seconds) # can't overflow |
| assert isinstance(s, int) |
| assert abs(s) <= 2 * 24 * 3600 |
| # seconds isn't referenced again before redefinition |
| |
| usdouble = secondsfrac * 1e6 |
| assert abs(usdouble) < 2.1e6 # exact value not critical |
| # secondsfrac isn't referenced again |
| |
| if isinstance(microseconds, float): |
| microseconds = round(microseconds + usdouble) |
| seconds, microseconds = divmod(microseconds, 1000000) |
| days, seconds = divmod(seconds, 24*3600) |
| d += days |
| s += seconds |
| else: |
| microseconds = int(microseconds) |
| seconds, microseconds = divmod(microseconds, 1000000) |
| days, seconds = divmod(seconds, 24*3600) |
| d += days |
| s += seconds |
| microseconds = round(microseconds + usdouble) |
| assert isinstance(s, int) |
| assert isinstance(microseconds, int) |
| assert abs(s) <= 3 * 24 * 3600 |
| assert abs(microseconds) < 3.1e6 |
| |
| # Just a little bit of carrying possible for microseconds and seconds. |
| seconds, us = divmod(microseconds, 1000000) |
| s += seconds |
| days, s = divmod(s, 24*3600) |
| d += days |
| |
| assert isinstance(d, int) |
| assert isinstance(s, int) and 0 <= s < 24*3600 |
| assert isinstance(us, int) and 0 <= us < 1000000 |
| |
| if abs(d) > 999999999: |
| raise OverflowError("timedelta # of days is too large: %d" % d) |
| |
| self = object.__new__(cls) |
| self._days = d |
| self._seconds = s |
| self._microseconds = us |
| self._hashcode = -1 |
| return self |
| |
| def __repr__(self): |
| args = [] |
| if self._days: |
| args.append("days=%d" % self._days) |
| if self._seconds: |
| args.append("seconds=%d" % self._seconds) |
| if self._microseconds: |
| args.append("microseconds=%d" % self._microseconds) |
| if not args: |
| args.append('0') |
| return "%s.%s(%s)" % (self.__class__.__module__, |
| self.__class__.__qualname__, |
| ', '.join(args)) |
| |
| def __str__(self): |
| mm, ss = divmod(self._seconds, 60) |
| hh, mm = divmod(mm, 60) |
| s = "%d:%02d:%02d" % (hh, mm, ss) |
| if self._days: |
| def plural(n): |
| return n, abs(n) != 1 and "s" or "" |
| s = ("%d day%s, " % plural(self._days)) + s |
| if self._microseconds: |
| s = s + ".%06d" % self._microseconds |
| return s |
| |
| def total_seconds(self): |
| """Total seconds in the duration.""" |
| return ((self.days * 86400 + self.seconds) * 10**6 + |
| self.microseconds) / 10**6 |
| |
| # Read-only field accessors |
| @property |
| def days(self): |
| """days""" |
| return self._days |
| |
| @property |
| def seconds(self): |
| """seconds""" |
| return self._seconds |
| |
| @property |
| def microseconds(self): |
| """microseconds""" |
| return self._microseconds |
| |
| def __add__(self, other): |
| if isinstance(other, timedelta): |
| # for CPython compatibility, we cannot use |
| # our __class__ here, but need a real timedelta |
| return timedelta(self._days + other._days, |
| self._seconds + other._seconds, |
| self._microseconds + other._microseconds) |
| return NotImplemented |
| |
| __radd__ = __add__ |
| |
| def __sub__(self, other): |
| if isinstance(other, timedelta): |
| # for CPython compatibility, we cannot use |
| # our __class__ here, but need a real timedelta |
| return timedelta(self._days - other._days, |
| self._seconds - other._seconds, |
| self._microseconds - other._microseconds) |
| return NotImplemented |
| |
| def __rsub__(self, other): |
| if isinstance(other, timedelta): |
| return -self + other |
| return NotImplemented |
| |
| def __neg__(self): |
| # for CPython compatibility, we cannot use |
| # our __class__ here, but need a real timedelta |
| return timedelta(-self._days, |
| -self._seconds, |
| -self._microseconds) |
| |
| def __pos__(self): |
| return self |
| |
| def __abs__(self): |
| if self._days < 0: |
| return -self |
| else: |
| return self |
| |
| def __mul__(self, other): |
| if isinstance(other, int): |
| # for CPython compatibility, we cannot use |
| # our __class__ here, but need a real timedelta |
| return timedelta(self._days * other, |
| self._seconds * other, |
| self._microseconds * other) |
| if isinstance(other, float): |
| usec = self._to_microseconds() |
| a, b = other.as_integer_ratio() |
| return timedelta(0, 0, _divide_and_round(usec * a, b)) |
| return NotImplemented |
| |
| __rmul__ = __mul__ |
| |
| def _to_microseconds(self): |
| return ((self._days * (24*3600) + self._seconds) * 1000000 + |
| self._microseconds) |
| |
| def __floordiv__(self, other): |
| if not isinstance(other, (int, timedelta)): |
| return NotImplemented |
| usec = self._to_microseconds() |
| if isinstance(other, timedelta): |
| return usec // other._to_microseconds() |
| if isinstance(other, int): |
| return timedelta(0, 0, usec // other) |
| |
| def __truediv__(self, other): |
| if not isinstance(other, (int, float, timedelta)): |
| return NotImplemented |
| usec = self._to_microseconds() |
| if isinstance(other, timedelta): |
| return usec / other._to_microseconds() |
| if isinstance(other, int): |
| return timedelta(0, 0, _divide_and_round(usec, other)) |
| if isinstance(other, float): |
| a, b = other.as_integer_ratio() |
| return timedelta(0, 0, _divide_and_round(b * usec, a)) |
| |
| def __mod__(self, other): |
| if isinstance(other, timedelta): |
| r = self._to_microseconds() % other._to_microseconds() |
| return timedelta(0, 0, r) |
| return NotImplemented |
| |
| def __divmod__(self, other): |
| if isinstance(other, timedelta): |
| q, r = divmod(self._to_microseconds(), |
| other._to_microseconds()) |
| return q, timedelta(0, 0, r) |
| return NotImplemented |
| |
| # Comparisons of timedelta objects with other. |
| |
| def __eq__(self, other): |
| if isinstance(other, timedelta): |
| return self._cmp(other) == 0 |
| else: |
| return False |
| |
| def __le__(self, other): |
| if isinstance(other, timedelta): |
| return self._cmp(other) <= 0 |
| else: |
| _cmperror(self, other) |
| |
| def __lt__(self, other): |
| if isinstance(other, timedelta): |
| return self._cmp(other) < 0 |
| else: |
| _cmperror(self, other) |
| |
| def __ge__(self, other): |
| if isinstance(other, timedelta): |
| return self._cmp(other) >= 0 |
| else: |
| _cmperror(self, other) |
| |
| def __gt__(self, other): |
| if isinstance(other, timedelta): |
| return self._cmp(other) > 0 |
| else: |
| _cmperror(self, other) |
| |
| def _cmp(self, other): |
| assert isinstance(other, timedelta) |
| return _cmp(self._getstate(), other._getstate()) |
| |
| def __hash__(self): |
| if self._hashcode == -1: |
| self._hashcode = hash(self._getstate()) |
| return self._hashcode |
| |
| def __bool__(self): |
| return (self._days != 0 or |
| self._seconds != 0 or |
| self._microseconds != 0) |
| |
| # Pickle support. |
| |
| def _getstate(self): |
| return (self._days, self._seconds, self._microseconds) |
| |
| def __reduce__(self): |
| return (self.__class__, self._getstate()) |
| |
| timedelta.min = timedelta(-999999999) |
| timedelta.max = timedelta(days=999999999, hours=23, minutes=59, seconds=59, |
| microseconds=999999) |
| timedelta.resolution = timedelta(microseconds=1) |
| |
| class date: |
| """Concrete date type. |
| |
| Constructors: |
| |
| __new__() |
| fromtimestamp() |
| today() |
| fromordinal() |
| |
| Operators: |
| |
| __repr__, __str__ |
| __eq__, __le__, __lt__, __ge__, __gt__, __hash__ |
| __add__, __radd__, __sub__ (add/radd only with timedelta arg) |
| |
| Methods: |
| |
| timetuple() |
| toordinal() |
| weekday() |
| isoweekday(), isocalendar(), isoformat() |
| ctime() |
| strftime() |
| |
| Properties (readonly): |
| year, month, day |
| """ |
| __slots__ = '_year', '_month', '_day', '_hashcode' |
| |
| def __new__(cls, year, month=None, day=None): |
| """Constructor. |
| |
| Arguments: |
| |
| year, month, day (required, base 1) |
| """ |
| if month is None and isinstance(year, bytes) and len(year) == 4 and \ |
| 1 <= year[2] <= 12: |
| # Pickle support |
| self = object.__new__(cls) |
| self.__setstate(year) |
| self._hashcode = -1 |
| return self |
| year, month, day = _check_date_fields(year, month, day) |
| self = object.__new__(cls) |
| self._year = year |
| self._month = month |
| self._day = day |
| self._hashcode = -1 |
| return self |
| |
| # Additional constructors |
| |
| @classmethod |
| def fromtimestamp(cls, t): |
| "Construct a date from a POSIX timestamp (like time.time())." |
| y, m, d, hh, mm, ss, weekday, jday, dst = _time.localtime(t) |
| return cls(y, m, d) |
| |
| @classmethod |
| def today(cls): |
| "Construct a date from time.time()." |
| t = _time.time() |
| return cls.fromtimestamp(t) |
| |
| @classmethod |
| def fromordinal(cls, n): |
| """Construct a date from a proleptic Gregorian ordinal. |
| |
| January 1 of year 1 is day 1. Only the year, month and day are |
| non-zero in the result. |
| """ |
| y, m, d = _ord2ymd(n) |
| return cls(y, m, d) |
| |
| @classmethod |
| def fromisoformat(cls, date_string): |
| """Construct a date from the output of date.isoformat().""" |
| if not isinstance(date_string, str): |
| raise TypeError('fromisoformat: argument must be str') |
| |
| try: |
| assert len(date_string) == 10 |
| return cls(*_parse_isoformat_date(date_string)) |
| except Exception: |
| raise ValueError('Invalid isoformat string: %s' % date_string) |
| |
| |
| # Conversions to string |
| |
| def __repr__(self): |
| """Convert to formal string, for repr(). |
| |
| >>> dt = datetime(2010, 1, 1) |
| >>> repr(dt) |
| 'datetime.datetime(2010, 1, 1, 0, 0)' |
| |
| >>> dt = datetime(2010, 1, 1, tzinfo=timezone.utc) |
| >>> repr(dt) |
| 'datetime.datetime(2010, 1, 1, 0, 0, tzinfo=datetime.timezone.utc)' |
| """ |
| return "%s.%s(%d, %d, %d)" % (self.__class__.__module__, |
| self.__class__.__qualname__, |
| self._year, |
| self._month, |
| self._day) |
| # XXX These shouldn't depend on time.localtime(), because that |
| # clips the usable dates to [1970 .. 2038). At least ctime() is |
| # easily done without using strftime() -- that's better too because |
| # strftime("%c", ...) is locale specific. |
| |
| |
| def ctime(self): |
| "Return ctime() style string." |
| weekday = self.toordinal() % 7 or 7 |
| return "%s %s %2d 00:00:00 %04d" % ( |
| _DAYNAMES[weekday], |
| _MONTHNAMES[self._month], |
| self._day, self._year) |
| |
| def strftime(self, fmt): |
| "Format using strftime()." |
| return _wrap_strftime(self, fmt, self.timetuple()) |
| |
| def __format__(self, fmt): |
| if not isinstance(fmt, str): |
| raise TypeError("must be str, not %s" % type(fmt).__name__) |
| if len(fmt) != 0: |
| return self.strftime(fmt) |
| return str(self) |
| |
| def isoformat(self): |
| """Return the date formatted according to ISO. |
| |
| This is 'YYYY-MM-DD'. |
| |
| References: |
| - http://www.w3.org/TR/NOTE-datetime |
| - http://www.cl.cam.ac.uk/~mgk25/iso-time.html |
| """ |
| return "%04d-%02d-%02d" % (self._year, self._month, self._day) |
| |
| __str__ = isoformat |
| |
| # Read-only field accessors |
| @property |
| def year(self): |
| """year (1-9999)""" |
| return self._year |
| |
| @property |
| def month(self): |
| """month (1-12)""" |
| return self._month |
| |
| @property |
| def day(self): |
| """day (1-31)""" |
| return self._day |
| |
| # Standard conversions, __eq__, __le__, __lt__, __ge__, __gt__, |
| # __hash__ (and helpers) |
| |
| def timetuple(self): |
| "Return local time tuple compatible with time.localtime()." |
| return _build_struct_time(self._year, self._month, self._day, |
| 0, 0, 0, -1) |
| |
| def toordinal(self): |
| """Return proleptic Gregorian ordinal for the year, month and day. |
| |
| January 1 of year 1 is day 1. Only the year, month and day values |
| contribute to the result. |
| """ |
| return _ymd2ord(self._year, self._month, self._day) |
| |
| def replace(self, year=None, month=None, day=None): |
| """Return a new date with new values for the specified fields.""" |
| if year is None: |
| year = self._year |
| if month is None: |
| month = self._month |
| if day is None: |
| day = self._day |
| return type(self)(year, month, day) |
| |
| # Comparisons of date objects with other. |
| |
| def __eq__(self, other): |
| if isinstance(other, date): |
| return self._cmp(other) == 0 |
| return NotImplemented |
| |
| def __le__(self, other): |
| if isinstance(other, date): |
| return self._cmp(other) <= 0 |
| return NotImplemented |
| |
| def __lt__(self, other): |
| if isinstance(other, date): |
| return self._cmp(other) < 0 |
| return NotImplemented |
| |
| def __ge__(self, other): |
| if isinstance(other, date): |
| return self._cmp(other) >= 0 |
| return NotImplemented |
| |
| def __gt__(self, other): |
| if isinstance(other, date): |
| return self._cmp(other) > 0 |
| return NotImplemented |
| |
| def _cmp(self, other): |
| assert isinstance(other, date) |
| y, m, d = self._year, self._month, self._day |
| y2, m2, d2 = other._year, other._month, other._day |
| return _cmp((y, m, d), (y2, m2, d2)) |
| |
| def __hash__(self): |
| "Hash." |
| if self._hashcode == -1: |
| self._hashcode = hash(self._getstate()) |
| return self._hashcode |
| |
| # Computations |
| |
| def __add__(self, other): |
| "Add a date to a timedelta." |
| if isinstance(other, timedelta): |
| o = self.toordinal() + other.days |
| if 0 < o <= _MAXORDINAL: |
| return date.fromordinal(o) |
| raise OverflowError("result out of range") |
| return NotImplemented |
| |
| __radd__ = __add__ |
| |
| def __sub__(self, other): |
| """Subtract two dates, or a date and a timedelta.""" |
| if isinstance(other, timedelta): |
| return self + timedelta(-other.days) |
| if isinstance(other, date): |
| days1 = self.toordinal() |
| days2 = other.toordinal() |
| return timedelta(days1 - days2) |
| return NotImplemented |
| |
| def weekday(self): |
| "Return day of the week, where Monday == 0 ... Sunday == 6." |
| return (self.toordinal() + 6) % 7 |
| |
| # Day-of-the-week and week-of-the-year, according to ISO |
| |
| def isoweekday(self): |
| "Return day of the week, where Monday == 1 ... Sunday == 7." |
| # 1-Jan-0001 is a Monday |
| return self.toordinal() % 7 or 7 |
| |
| def isocalendar(self): |
| """Return a 3-tuple containing ISO year, week number, and weekday. |
| |
| The first ISO week of the year is the (Mon-Sun) week |
| containing the year's first Thursday; everything else derives |
| from that. |
| |
| The first week is 1; Monday is 1 ... Sunday is 7. |
| |
| ISO calendar algorithm taken from |
| http://www.phys.uu.nl/~vgent/calendar/isocalendar.htm |
| (used with permission) |
| """ |
| year = self._year |
| week1monday = _isoweek1monday(year) |
| today = _ymd2ord(self._year, self._month, self._day) |
| # Internally, week and day have origin 0 |
| week, day = divmod(today - week1monday, 7) |
| if week < 0: |
| year -= 1 |
| week1monday = _isoweek1monday(year) |
| week, day = divmod(today - week1monday, 7) |
| elif week >= 52: |
| if today >= _isoweek1monday(year+1): |
| year += 1 |
| week = 0 |
| return year, week+1, day+1 |
| |
| # Pickle support. |
| |
| def _getstate(self): |
| yhi, ylo = divmod(self._year, 256) |
| return bytes([yhi, ylo, self._month, self._day]), |
| |
| def __setstate(self, string): |
| yhi, ylo, self._month, self._day = string |
| self._year = yhi * 256 + ylo |
| |
| def __reduce__(self): |
| return (self.__class__, self._getstate()) |
| |
| _date_class = date # so functions w/ args named "date" can get at the class |
| |
| date.min = date(1, 1, 1) |
| date.max = date(9999, 12, 31) |
| date.resolution = timedelta(days=1) |
| |
| |
| class tzinfo: |
| """Abstract base class for time zone info classes. |
| |
| Subclasses must override the name(), utcoffset() and dst() methods. |
| """ |
| __slots__ = () |
| |
| def tzname(self, dt): |
| "datetime -> string name of time zone." |
| raise NotImplementedError("tzinfo subclass must override tzname()") |
| |
| def utcoffset(self, dt): |
| "datetime -> timedelta, positive for east of UTC, negative for west of UTC" |
| raise NotImplementedError("tzinfo subclass must override utcoffset()") |
| |
| def dst(self, dt): |
| """datetime -> DST offset as timedelta, positive for east of UTC. |
| |
| Return 0 if DST not in effect. utcoffset() must include the DST |
| offset. |
| """ |
| raise NotImplementedError("tzinfo subclass must override dst()") |
| |
| def fromutc(self, dt): |
| "datetime in UTC -> datetime in local time." |
| |
| if not isinstance(dt, datetime): |
| raise TypeError("fromutc() requires a datetime argument") |
| if dt.tzinfo is not self: |
| raise ValueError("dt.tzinfo is not self") |
| |
| dtoff = dt.utcoffset() |
| if dtoff is None: |
| raise ValueError("fromutc() requires a non-None utcoffset() " |
| "result") |
| |
| # See the long comment block at the end of this file for an |
| # explanation of this algorithm. |
| dtdst = dt.dst() |
| if dtdst is None: |
| raise ValueError("fromutc() requires a non-None dst() result") |
| delta = dtoff - dtdst |
| if delta: |
| dt += delta |
| dtdst = dt.dst() |
| if dtdst is None: |
| raise ValueError("fromutc(): dt.dst gave inconsistent " |
| "results; cannot convert") |
| return dt + dtdst |
| |
| # Pickle support. |
| |
| def __reduce__(self): |
| getinitargs = getattr(self, "__getinitargs__", None) |
| if getinitargs: |
| args = getinitargs() |
| else: |
| args = () |
| getstate = getattr(self, "__getstate__", None) |
| if getstate: |
| state = getstate() |
| else: |
| state = getattr(self, "__dict__", None) or None |
| if state is None: |
| return (self.__class__, args) |
| else: |
| return (self.__class__, args, state) |
| |
| _tzinfo_class = tzinfo |
| |
| class time: |
| """Time with time zone. |
| |
| Constructors: |
| |
| __new__() |
| |
| Operators: |
| |
| __repr__, __str__ |
| __eq__, __le__, __lt__, __ge__, __gt__, __hash__ |
| |
| Methods: |
| |
| strftime() |
| isoformat() |
| utcoffset() |
| tzname() |
| dst() |
| |
| Properties (readonly): |
| hour, minute, second, microsecond, tzinfo, fold |
| """ |
| __slots__ = '_hour', '_minute', '_second', '_microsecond', '_tzinfo', '_hashcode', '_fold' |
| |
| def __new__(cls, hour=0, minute=0, second=0, microsecond=0, tzinfo=None, *, fold=0): |
| """Constructor. |
| |
| Arguments: |
| |
| hour, minute (required) |
| second, microsecond (default to zero) |
| tzinfo (default to None) |
| fold (keyword only, default to zero) |
| """ |
| if isinstance(hour, bytes) and len(hour) == 6 and hour[0]&0x7F < 24: |
| # Pickle support |
| self = object.__new__(cls) |
| self.__setstate(hour, minute or None) |
| self._hashcode = -1 |
| return self |
| hour, minute, second, microsecond, fold = _check_time_fields( |
| hour, minute, second, microsecond, fold) |
| _check_tzinfo_arg(tzinfo) |
| self = object.__new__(cls) |
| self._hour = hour |
| self._minute = minute |
| self._second = second |
| self._microsecond = microsecond |
| self._tzinfo = tzinfo |
| self._hashcode = -1 |
| self._fold = fold |
| return self |
| |
| # Read-only field accessors |
| @property |
| def hour(self): |
| """hour (0-23)""" |
| return self._hour |
| |
| @property |
| def minute(self): |
| """minute (0-59)""" |
| return self._minute |
| |
| @property |
| def second(self): |
| """second (0-59)""" |
| return self._second |
| |
| @property |
| def microsecond(self): |
| """microsecond (0-999999)""" |
| return self._microsecond |
| |
| @property |
| def tzinfo(self): |
| """timezone info object""" |
| return self._tzinfo |
| |
| @property |
| def fold(self): |
| return self._fold |
| |
| # Standard conversions, __hash__ (and helpers) |
| |
| # Comparisons of time objects with other. |
| |
| def __eq__(self, other): |
| if isinstance(other, time): |
| return self._cmp(other, allow_mixed=True) == 0 |
| else: |
| return False |
| |
| def __le__(self, other): |
| if isinstance(other, time): |
| return self._cmp(other) <= 0 |
| else: |
| _cmperror(self, other) |
| |
| def __lt__(self, other): |
| if isinstance(other, time): |
| return self._cmp(other) < 0 |
| else: |
| _cmperror(self, other) |
| |
| def __ge__(self, other): |
| if isinstance(other, time): |
| return self._cmp(other) >= 0 |
| else: |
| _cmperror(self, other) |
| |
| def __gt__(self, other): |
| if isinstance(other, time): |
| return self._cmp(other) > 0 |
| else: |
| _cmperror(self, other) |
| |
| def _cmp(self, other, allow_mixed=False): |
| assert isinstance(other, time) |
| mytz = self._tzinfo |
| ottz = other._tzinfo |
| myoff = otoff = None |
| |
| if mytz is ottz: |
| base_compare = True |
| else: |
| myoff = self.utcoffset() |
| otoff = other.utcoffset() |
| base_compare = myoff == otoff |
| |
| if base_compare: |
| return _cmp((self._hour, self._minute, self._second, |
| self._microsecond), |
| (other._hour, other._minute, other._second, |
| other._microsecond)) |
| if myoff is None or otoff is None: |
| if allow_mixed: |
| return 2 # arbitrary non-zero value |
| else: |
| raise TypeError("cannot compare naive and aware times") |
| myhhmm = self._hour * 60 + self._minute - myoff//timedelta(minutes=1) |
| othhmm = other._hour * 60 + other._minute - otoff//timedelta(minutes=1) |
| return _cmp((myhhmm, self._second, self._microsecond), |
| (othhmm, other._second, other._microsecond)) |
| |
| def __hash__(self): |
| """Hash.""" |
| if self._hashcode == -1: |
| if self.fold: |
| t = self.replace(fold=0) |
| else: |
| t = self |
| tzoff = t.utcoffset() |
| if not tzoff: # zero or None |
| self._hashcode = hash(t._getstate()[0]) |
| else: |
| h, m = divmod(timedelta(hours=self.hour, minutes=self.minute) - tzoff, |
| timedelta(hours=1)) |
| assert not m % timedelta(minutes=1), "whole minute" |
| m //= timedelta(minutes=1) |
| if 0 <= h < 24: |
| self._hashcode = hash(time(h, m, self.second, self.microsecond)) |
| else: |
| self._hashcode = hash((h, m, self.second, self.microsecond)) |
| return self._hashcode |
| |
| # Conversion to string |
| |
| def _tzstr(self): |
| """Return formatted timezone offset (+xx:xx) or an empty string.""" |
| off = self.utcoffset() |
| return _format_offset(off) |
| |
| def __repr__(self): |
| """Convert to formal string, for repr().""" |
| if self._microsecond != 0: |
| s = ", %d, %d" % (self._second, self._microsecond) |
| elif self._second != 0: |
| s = ", %d" % self._second |
| else: |
| s = "" |
| s= "%s.%s(%d, %d%s)" % (self.__class__.__module__, |
| self.__class__.__qualname__, |
| self._hour, self._minute, s) |
| if self._tzinfo is not None: |
| assert s[-1:] == ")" |
| s = s[:-1] + ", tzinfo=%r" % self._tzinfo + ")" |
| if self._fold: |
| assert s[-1:] == ")" |
| s = s[:-1] + ", fold=1)" |
| return s |
| |
| def isoformat(self, timespec='auto'): |
| """Return the time formatted according to ISO. |
| |
| The full format is 'HH:MM:SS.mmmmmm+zz:zz'. By default, the fractional |
| part is omitted if self.microsecond == 0. |
| |
| The optional argument timespec specifies the number of additional |
| terms of the time to include. |
| """ |
| s = _format_time(self._hour, self._minute, self._second, |
| self._microsecond, timespec) |
| tz = self._tzstr() |
| if tz: |
| s += tz |
| return s |
| |
| __str__ = isoformat |
| |
| @classmethod |
| def fromisoformat(cls, time_string): |
| """Construct a time from the output of isoformat().""" |
| if not isinstance(time_string, str): |
| raise TypeError('fromisoformat: argument must be str') |
| |
| try: |
| return cls(*_parse_isoformat_time(time_string)) |
| except Exception: |
| raise ValueError('Invalid isoformat string: %s' % time_string) |
| |
| |
| def strftime(self, fmt): |
| """Format using strftime(). The date part of the timestamp passed |
| to underlying strftime should not be used. |
| """ |
| # The year must be >= 1000 else Python's strftime implementation |
| # can raise a bogus exception. |
| timetuple = (1900, 1, 1, |
| self._hour, self._minute, self._second, |
| 0, 1, -1) |
| return _wrap_strftime(self, fmt, timetuple) |
| |
| def __format__(self, fmt): |
| if not isinstance(fmt, str): |
| raise TypeError("must be str, not %s" % type(fmt).__name__) |
| if len(fmt) != 0: |
| return self.strftime(fmt) |
| return str(self) |
| |
| # Timezone functions |
| |
| def utcoffset(self): |
| """Return the timezone offset as timedelta, positive east of UTC |
| (negative west of UTC).""" |
| if self._tzinfo is None: |
| return None |
| offset = self._tzinfo.utcoffset(None) |
| _check_utc_offset("utcoffset", offset) |
| return offset |
| |
| def tzname(self): |
| """Return the timezone name. |
| |
| Note that the name is 100% informational -- there's no requirement that |
| it mean anything in particular. For example, "GMT", "UTC", "-500", |
| "-5:00", "EDT", "US/Eastern", "America/New York" are all valid replies. |
| """ |
| if self._tzinfo is None: |
| return None |
| name = self._tzinfo.tzname(None) |
| _check_tzname(name) |
| return name |
| |
| def dst(self): |
| """Return 0 if DST is not in effect, or the DST offset (as timedelta |
| positive eastward) if DST is in effect. |
| |
| This is purely informational; the DST offset has already been added to |
| the UTC offset returned by utcoffset() if applicable, so there's no |
| need to consult dst() unless you're interested in displaying the DST |
| info. |
| """ |
| if self._tzinfo is None: |
| return None |
| offset = self._tzinfo.dst(None) |
| _check_utc_offset("dst", offset) |
| return offset |
| |
| def replace(self, hour=None, minute=None, second=None, microsecond=None, |
| tzinfo=True, *, fold=None): |
| """Return a new time with new values for the specified fields.""" |
| if hour is None: |
| hour = self.hour |
| if minute is None: |
| minute = self.minute |
| if second is None: |
| second = self.second |
| if microsecond is None: |
| microsecond = self.microsecond |
| if tzinfo is True: |
| tzinfo = self.tzinfo |
| if fold is None: |
| fold = self._fold |
| return type(self)(hour, minute, second, microsecond, tzinfo, fold=fold) |
| |
| # Pickle support. |
| |
| def _getstate(self, protocol=3): |
| us2, us3 = divmod(self._microsecond, 256) |
| us1, us2 = divmod(us2, 256) |
| h = self._hour |
| if self._fold and protocol > 3: |
| h += 128 |
| basestate = bytes([h, self._minute, self._second, |
| us1, us2, us3]) |
| if self._tzinfo is None: |
| return (basestate,) |
| else: |
| return (basestate, self._tzinfo) |
| |
| def __setstate(self, string, tzinfo): |
| if tzinfo is not None and not isinstance(tzinfo, _tzinfo_class): |
| raise TypeError("bad tzinfo state arg") |
| h, self._minute, self._second, us1, us2, us3 = string |
| if h > 127: |
| self._fold = 1 |
| self._hour = h - 128 |
| else: |
| self._fold = 0 |
| self._hour = h |
| self._microsecond = (((us1 << 8) | us2) << 8) | us3 |
| self._tzinfo = tzinfo |
| |
| def __reduce_ex__(self, protocol): |
| return (time, self._getstate(protocol)) |
| |
| def __reduce__(self): |
| return self.__reduce_ex__(2) |
| |
| _time_class = time # so functions w/ args named "time" can get at the class |
| |
| time.min = time(0, 0, 0) |
| time.max = time(23, 59, 59, 999999) |
| time.resolution = timedelta(microseconds=1) |
| |
| class datetime(date): |
| """datetime(year, month, day[, hour[, minute[, second[, microsecond[,tzinfo]]]]]) |
| |
| The year, month and day arguments are required. tzinfo may be None, or an |
| instance of a tzinfo subclass. The remaining arguments may be ints. |
| """ |
| __slots__ = date.__slots__ + time.__slots__ |
| |
| def __new__(cls, year, month=None, day=None, hour=0, minute=0, second=0, |
| microsecond=0, tzinfo=None, *, fold=0): |
| if isinstance(year, bytes) and len(year) == 10 and 1 <= year[2]&0x7F <= 12: |
| # Pickle support |
| self = object.__new__(cls) |
| self.__setstate(year, month) |
| self._hashcode = -1 |
| return self |
| year, month, day = _check_date_fields(year, month, day) |
| hour, minute, second, microsecond, fold = _check_time_fields( |
| hour, minute, second, microsecond, fold) |
| _check_tzinfo_arg(tzinfo) |
| self = object.__new__(cls) |
| self._year = year |
| self._month = month |
| self._day = day |
| self._hour = hour |
| self._minute = minute |
| self._second = second |
| self._microsecond = microsecond |
| self._tzinfo = tzinfo |
| self._hashcode = -1 |
| self._fold = fold |
| return self |
| |
| # Read-only field accessors |
| @property |
| def hour(self): |
| """hour (0-23)""" |
| return self._hour |
| |
| @property |
| def minute(self): |
| """minute (0-59)""" |
| return self._minute |
| |
| @property |
| def second(self): |
| """second (0-59)""" |
| return self._second |
| |
| @property |
| def microsecond(self): |
| """microsecond (0-999999)""" |
| return self._microsecond |
| |
| @property |
| def tzinfo(self): |
| """timezone info object""" |
| return self._tzinfo |
| |
| @property |
| def fold(self): |
| return self._fold |
| |
| @classmethod |
| def _fromtimestamp(cls, t, utc, tz): |
| """Construct a datetime from a POSIX timestamp (like time.time()). |
| |
| A timezone info object may be passed in as well. |
| """ |
| frac, t = _math.modf(t) |
| us = round(frac * 1e6) |
| if us >= 1000000: |
| t += 1 |
| us -= 1000000 |
| elif us < 0: |
| t -= 1 |
| us += 1000000 |
| |
| converter = _time.gmtime if utc else _time.localtime |
| y, m, d, hh, mm, ss, weekday, jday, dst = converter(t) |
| ss = min(ss, 59) # clamp out leap seconds if the platform has them |
| result = cls(y, m, d, hh, mm, ss, us, tz) |
| if tz is None: |
| # As of version 2015f max fold in IANA database is |
| # 23 hours at 1969-09-30 13:00:00 in Kwajalein. |
| # Let's probe 24 hours in the past to detect a transition: |
| max_fold_seconds = 24 * 3600 |
| y, m, d, hh, mm, ss = converter(t - max_fold_seconds)[:6] |
| probe1 = cls(y, m, d, hh, mm, ss, us, tz) |
| trans = result - probe1 - timedelta(0, max_fold_seconds) |
| if trans.days < 0: |
| y, m, d, hh, mm, ss = converter(t + trans // timedelta(0, 1))[:6] |
| probe2 = cls(y, m, d, hh, mm, ss, us, tz) |
| if probe2 == result: |
| result._fold = 1 |
| else: |
| result = tz.fromutc(result) |
| return result |
| |
| @classmethod |
| def fromtimestamp(cls, t, tz=None): |
| """Construct a datetime from a POSIX timestamp (like time.time()). |
| |
| A timezone info object may be passed in as well. |
| """ |
| _check_tzinfo_arg(tz) |
| |
| return cls._fromtimestamp(t, tz is not None, tz) |
| |
| @classmethod |
| def utcfromtimestamp(cls, t): |
| """Construct a naive UTC datetime from a POSIX timestamp.""" |
| return cls._fromtimestamp(t, True, None) |
| |
| @classmethod |
| def now(cls, tz=None): |
| "Construct a datetime from time.time() and optional time zone info." |
| t = _time.time() |
| return cls.fromtimestamp(t, tz) |
| |
| @classmethod |
| def utcnow(cls): |
| "Construct a UTC datetime from time.time()." |
| t = _time.time() |
| return cls.utcfromtimestamp(t) |
| |
| @classmethod |
| def combine(cls, date, time, tzinfo=True): |
| "Construct a datetime from a given date and a given time." |
| if not isinstance(date, _date_class): |
| raise TypeError("date argument must be a date instance") |
| if not isinstance(time, _time_class): |
| raise TypeError("time argument must be a time instance") |
| if tzinfo is True: |
| tzinfo = time.tzinfo |
| return cls(date.year, date.month, date.day, |
| time.hour, time.minute, time.second, time.microsecond, |
| tzinfo, fold=time.fold) |
| |
| @classmethod |
| def fromisoformat(cls, date_string): |
| """Construct a datetime from the output of datetime.isoformat().""" |
| if not isinstance(date_string, str): |
| raise TypeError('fromisoformat: argument must be str') |
| |
| # Split this at the separator |
| dstr = date_string[0:10] |
| tstr = date_string[11:] |
| |
| try: |
| date_components = _parse_isoformat_date(dstr) |
| except ValueError: |
| raise ValueError('Invalid isoformat string: %s' % date_string) |
| |
| if tstr: |
| try: |
| time_components = _parse_isoformat_time(tstr) |
| except ValueError: |
| raise ValueError('Invalid isoformat string: %s' % date_string) |
| else: |
| time_components = [0, 0, 0, 0, None] |
| |
| return cls(*(date_components + time_components)) |
| |
| def timetuple(self): |
| "Return local time tuple compatible with time.localtime()." |
| dst = self.dst() |
| if dst is None: |
| dst = -1 |
| elif dst: |
| dst = 1 |
| else: |
| dst = 0 |
| return _build_struct_time(self.year, self.month, self.day, |
| self.hour, self.minute, self.second, |
| dst) |
| |
| def _mktime(self): |
| """Return integer POSIX timestamp.""" |
| epoch = datetime(1970, 1, 1) |
| max_fold_seconds = 24 * 3600 |
| t = (self - epoch) // timedelta(0, 1) |
| def local(u): |
| y, m, d, hh, mm, ss = _time.localtime(u)[:6] |
| return (datetime(y, m, d, hh, mm, ss) - epoch) // timedelta(0, 1) |
| |
| # Our goal is to solve t = local(u) for u. |
| a = local(t) - t |
| u1 = t - a |
| t1 = local(u1) |
| if t1 == t: |
| # We found one solution, but it may not be the one we need. |
| # Look for an earlier solution (if `fold` is 0), or a |
| # later one (if `fold` is 1). |
| u2 = u1 + (-max_fold_seconds, max_fold_seconds)[self.fold] |
| b = local(u2) - u2 |
| if a == b: |
| return u1 |
| else: |
| b = t1 - u1 |
| assert a != b |
| u2 = t - b |
| t2 = local(u2) |
| if t2 == t: |
| return u2 |
| if t1 == t: |
| return u1 |
| # We have found both offsets a and b, but neither t - a nor t - b is |
| # a solution. This means t is in the gap. |
| return (max, min)[self.fold](u1, u2) |
| |
| |
| def timestamp(self): |
| "Return POSIX timestamp as float" |
| if self._tzinfo is None: |
| s = self._mktime() |
| return s + self.microsecond / 1e6 |
| else: |
| return (self - _EPOCH).total_seconds() |
| |
| def utctimetuple(self): |
| "Return UTC time tuple compatible with time.gmtime()." |
| offset = self.utcoffset() |
| if offset: |
| self -= offset |
| y, m, d = self.year, self.month, self.day |
| hh, mm, ss = self.hour, self.minute, self.second |
| return _build_struct_time(y, m, d, hh, mm, ss, 0) |
| |
| def date(self): |
| "Return the date part." |
| return date(self._year, self._month, self._day) |
| |
| def time(self): |
| "Return the time part, with tzinfo None." |
| return time(self.hour, self.minute, self.second, self.microsecond, fold=self.fold) |
| |
| def timetz(self): |
| "Return the time part, with same tzinfo." |
| return time(self.hour, self.minute, self.second, self.microsecond, |
| self._tzinfo, fold=self.fold) |
| |
| def replace(self, year=None, month=None, day=None, hour=None, |
| minute=None, second=None, microsecond=None, tzinfo=True, |
| *, fold=None): |
| """Return a new datetime with new values for the specified fields.""" |
| if year is None: |
| year = self.year |
| if month is None: |
| month = self.month |
| if day is None: |
| day = self.day |
| if hour is None: |
| hour = self.hour |
| if minute is None: |
| minute = self.minute |
| if second is None: |
| second = self.second |
| if microsecond is None: |
| microsecond = self.microsecond |
| if tzinfo is True: |
| tzinfo = self.tzinfo |
| if fold is None: |
| fold = self.fold |
| return type(self)(year, month, day, hour, minute, second, |
| microsecond, tzinfo, fold=fold) |
| |
| def _local_timezone(self): |
| if self.tzinfo is None: |
| ts = self._mktime() |
| else: |
| ts = (self - _EPOCH) // timedelta(seconds=1) |
| localtm = _time.localtime(ts) |
| local = datetime(*localtm[:6]) |
| try: |
| # Extract TZ data if available |
| gmtoff = localtm.tm_gmtoff |
| zone = localtm.tm_zone |
| except AttributeError: |
| delta = local - datetime(*_time.gmtime(ts)[:6]) |
| zone = _time.strftime('%Z', localtm) |
| tz = timezone(delta, zone) |
| else: |
| tz = timezone(timedelta(seconds=gmtoff), zone) |
| return tz |
| |
| def astimezone(self, tz=None): |
| if tz is None: |
| tz = self._local_timezone() |
| elif not isinstance(tz, tzinfo): |
| raise TypeError("tz argument must be an instance of tzinfo") |
| |
| mytz = self.tzinfo |
| if mytz is None: |
| mytz = self._local_timezone() |
| |
| if tz is mytz: |
| return self |
| |
| # Convert self to UTC, and attach the new time zone object. |
| myoffset = mytz.utcoffset(self) |
| if myoffset is None: |
| raise ValueError("astimezone() requires an aware datetime") |
| utc = (self - myoffset).replace(tzinfo=tz) |
| |
| # Convert from UTC to tz's local time. |
| return tz.fromutc(utc) |
| |
| # Ways to produce a string. |
| |
| def ctime(self): |
| "Return ctime() style string." |
| weekday = self.toordinal() % 7 or 7 |
| return "%s %s %2d %02d:%02d:%02d %04d" % ( |
| _DAYNAMES[weekday], |
| _MONTHNAMES[self._month], |
| self._day, |
| self._hour, self._minute, self._second, |
| self._year) |
| |
| def isoformat(self, sep='T', timespec='auto'): |
| """Return the time formatted according to ISO. |
| |
| The full format looks like 'YYYY-MM-DD HH:MM:SS.mmmmmm'. |
| By default, the fractional part is omitted if self.microsecond == 0. |
| |
| If self.tzinfo is not None, the UTC offset is also attached, giving |
| giving a full format of 'YYYY-MM-DD HH:MM:SS.mmmmmm+HH:MM'. |
| |
| Optional argument sep specifies the separator between date and |
| time, default 'T'. |
| |
| The optional argument timespec specifies the number of additional |
| terms of the time to include. |
| """ |
| s = ("%04d-%02d-%02d%c" % (self._year, self._month, self._day, sep) + |
| _format_time(self._hour, self._minute, self._second, |
| self._microsecond, timespec)) |
| |
| off = self.utcoffset() |
| tz = _format_offset(off) |
| if tz: |
| s += tz |
| |
| return s |
| |
| def __repr__(self): |
| """Convert to formal string, for repr().""" |
| L = [self._year, self._month, self._day, # These are never zero |
| self._hour, self._minute, self._second, self._microsecond] |
| if L[-1] == 0: |
| del L[-1] |
| if L[-1] == 0: |
| del L[-1] |
| s = "%s.%s(%s)" % (self.__class__.__module__, |
| self.__class__.__qualname__, |
| ", ".join(map(str, L))) |
| if self._tzinfo is not None: |
| assert s[-1:] == ")" |
| s = s[:-1] + ", tzinfo=%r" % self._tzinfo + ")" |
| if self._fold: |
| assert s[-1:] == ")" |
| s = s[:-1] + ", fold=1)" |
| return s |
| |
| def __str__(self): |
| "Convert to string, for str()." |
| return self.isoformat(sep=' ') |
| |
| @classmethod |
| def strptime(cls, date_string, format): |
| 'string, format -> new datetime parsed from a string (like time.strptime()).' |
| import _strptime |
| return _strptime._strptime_datetime(cls, date_string, format) |
| |
| def utcoffset(self): |
| """Return the timezone offset as timedelta positive east of UTC (negative west of |
| UTC).""" |
| if self._tzinfo is None: |
| return None |
| offset = self._tzinfo.utcoffset(self) |
| _check_utc_offset("utcoffset", offset) |
| return offset |
| |
| def tzname(self): |
| """Return the timezone name. |
| |
| Note that the name is 100% informational -- there's no requirement that |
| it mean anything in particular. For example, "GMT", "UTC", "-500", |
| "-5:00", "EDT", "US/Eastern", "America/New York" are all valid replies. |
| """ |
| if self._tzinfo is None: |
| return None |
| name = self._tzinfo.tzname(self) |
| _check_tzname(name) |
| return name |
| |
| def dst(self): |
| """Return 0 if DST is not in effect, or the DST offset (as timedelta |
| positive eastward) if DST is in effect. |
| |
| This is purely informational; the DST offset has already been added to |
| the UTC offset returned by utcoffset() if applicable, so there's no |
| need to consult dst() unless you're interested in displaying the DST |
| info. |
| """ |
| if self._tzinfo is None: |
| return None |
| offset = self._tzinfo.dst(self) |
| _check_utc_offset("dst", offset) |
| return offset |
| |
| # Comparisons of datetime objects with other. |
| |
| def __eq__(self, other): |
| if isinstance(other, datetime): |
| return self._cmp(other, allow_mixed=True) == 0 |
| elif not isinstance(other, date): |
| return NotImplemented |
| else: |
| return False |
| |
| def __le__(self, other): |
| if isinstance(other, datetime): |
| return self._cmp(other) <= 0 |
| elif not isinstance(other, date): |
| return NotImplemented |
| else: |
| _cmperror(self, other) |
| |
| def __lt__(self, other): |
| if isinstance(other, datetime): |
| return self._cmp(other) < 0 |
| elif not isinstance(other, date): |
| return NotImplemented |
| else: |
| _cmperror(self, other) |
| |
| def __ge__(self, other): |
| if isinstance(other, datetime): |
| return self._cmp(other) >= 0 |
| elif not isinstance(other, date): |
| return NotImplemented |
| else: |
| _cmperror(self, other) |
| |
| def __gt__(self, other): |
| if isinstance(other, datetime): |
| return self._cmp(other) > 0 |
| elif not isinstance(other, date): |
| return NotImplemented |
| else: |
| _cmperror(self, other) |
| |
| def _cmp(self, other, allow_mixed=False): |
| assert isinstance(other, datetime) |
| mytz = self._tzinfo |
| ottz = other._tzinfo |
| myoff = otoff = None |
| |
| if mytz is ottz: |
| base_compare = True |
| else: |
| myoff = self.utcoffset() |
| otoff = other.utcoffset() |
| # Assume that allow_mixed means that we are called from __eq__ |
| if allow_mixed: |
| if myoff != self.replace(fold=not self.fold).utcoffset(): |
| return 2 |
| if otoff != other.replace(fold=not other.fold).utcoffset(): |
| return 2 |
| base_compare = myoff == otoff |
| |
| if base_compare: |
| return _cmp((self._year, self._month, self._day, |
| self._hour, self._minute, self._second, |
| self._microsecond), |
| (other._year, other._month, other._day, |
| other._hour, other._minute, other._second, |
| other._microsecond)) |
| if myoff is None or otoff is None: |
| if allow_mixed: |
| return 2 # arbitrary non-zero value |
| else: |
| raise TypeError("cannot compare naive and aware datetimes") |
| # XXX What follows could be done more efficiently... |
| diff = self - other # this will take offsets into account |
| if diff.days < 0: |
| return -1 |
| return diff and 1 or 0 |
| |
| def __add__(self, other): |
| "Add a datetime and a timedelta." |
| if not isinstance(other, timedelta): |
| return NotImplemented |
| delta = timedelta(self.toordinal(), |
| hours=self._hour, |
| minutes=self._minute, |
| seconds=self._second, |
| microseconds=self._microsecond) |
| delta += other |
| hour, rem = divmod(delta.seconds, 3600) |
| minute, second = divmod(rem, 60) |
| if 0 < delta.days <= _MAXORDINAL: |
| return datetime.combine(date.fromordinal(delta.days), |
| time(hour, minute, second, |
| delta.microseconds, |
| tzinfo=self._tzinfo)) |
| raise OverflowError("result out of range") |
| |
| __radd__ = __add__ |
| |
| def __sub__(self, other): |
| "Subtract two datetimes, or a datetime and a timedelta." |
| if not isinstance(other, datetime): |
| if isinstance(other, timedelta): |
| return self + -other |
| return NotImplemented |
| |
| days1 = self.toordinal() |
| days2 = other.toordinal() |
| secs1 = self._second + self._minute * 60 + self._hour * 3600 |
| secs2 = other._second + other._minute * 60 + other._hour * 3600 |
| base = timedelta(days1 - days2, |
| secs1 - secs2, |
| self._microsecond - other._microsecond) |
| if self._tzinfo is other._tzinfo: |
| return base |
| myoff = self.utcoffset() |
| otoff = other.utcoffset() |
| if myoff == otoff: |
| return base |
| if myoff is None or otoff is None: |
| raise TypeError("cannot mix naive and timezone-aware time") |
| return base + otoff - myoff |
| |
| def __hash__(self): |
| if self._hashcode == -1: |
| if self.fold: |
| t = self.replace(fold=0) |
| else: |
| t = self |
| tzoff = t.utcoffset() |
| if tzoff is None: |
| self._hashcode = hash(t._getstate()[0]) |
| else: |
| days = _ymd2ord(self.year, self.month, self.day) |
| seconds = self.hour * 3600 + self.minute * 60 + self.second |
| self._hashcode = hash(timedelta(days, seconds, self.microsecond) - tzoff) |
| return self._hashcode |
| |
| # Pickle support. |
| |
| def _getstate(self, protocol=3): |
| yhi, ylo = divmod(self._year, 256) |
| us2, us3 = divmod(self._microsecond, 256) |
| us1, us2 = divmod(us2, 256) |
| m = self._month |
| if self._fold and protocol > 3: |
| m += 128 |
| basestate = bytes([yhi, ylo, m, self._day, |
| self._hour, self._minute, self._second, |
| us1, us2, us3]) |
| if self._tzinfo is None: |
| return (basestate,) |
| else: |
| return (basestate, self._tzinfo) |
| |
| def __setstate(self, string, tzinfo): |
| if tzinfo is not None and not isinstance(tzinfo, _tzinfo_class): |
| raise TypeError("bad tzinfo state arg") |
| (yhi, ylo, m, self._day, self._hour, |
| self._minute, self._second, us1, us2, us3) = string |
| if m > 127: |
| self._fold = 1 |
| self._month = m - 128 |
| else: |
| self._fold = 0 |
| self._month = m |
| self._year = yhi * 256 + ylo |
| self._microsecond = (((us1 << 8) | us2) << 8) | us3 |
| self._tzinfo = tzinfo |
| |
| def __reduce_ex__(self, protocol): |
| return (self.__class__, self._getstate(protocol)) |
| |
| def __reduce__(self): |
| return self.__reduce_ex__(2) |
| |
| |
| datetime.min = datetime(1, 1, 1) |
| datetime.max = datetime(9999, 12, 31, 23, 59, 59, 999999) |
| datetime.resolution = timedelta(microseconds=1) |
| |
| |
| def _isoweek1monday(year): |
| # Helper to calculate the day number of the Monday starting week 1 |
| # XXX This could be done more efficiently |
| THURSDAY = 3 |
| firstday = _ymd2ord(year, 1, 1) |
| firstweekday = (firstday + 6) % 7 # See weekday() above |
| week1monday = firstday - firstweekday |
| if firstweekday > THURSDAY: |
| week1monday += 7 |
| return week1monday |
| |
| class timezone(tzinfo): |
| __slots__ = '_offset', '_name' |
| |
| # Sentinel value to disallow None |
| _Omitted = object() |
| def __new__(cls, offset, name=_Omitted): |
| if not isinstance(offset, timedelta): |
| raise TypeError("offset must be a timedelta") |
| if name is cls._Omitted: |
| if not offset: |
| return cls.utc |
| name = None |
| elif not isinstance(name, str): |
| raise TypeError("name must be a string") |
| if not cls._minoffset <= offset <= cls._maxoffset: |
| raise ValueError("offset must be a timedelta " |
| "strictly between -timedelta(hours=24) and " |
| "timedelta(hours=24).") |
| return cls._create(offset, name) |
| |
| @classmethod |
| def _create(cls, offset, name=None): |
| self = tzinfo.__new__(cls) |
| self._offset = offset |
| self._name = name |
| return self |
| |
| def __getinitargs__(self): |
| """pickle support""" |
| if self._name is None: |
| return (self._offset,) |
| return (self._offset, self._name) |
| |
| def __eq__(self, other): |
| if type(other) != timezone: |
| return False |
| return self._offset == other._offset |
| |
| def __hash__(self): |
| return hash(self._offset) |
| |
| def __repr__(self): |
| """Convert to formal string, for repr(). |
| |
| >>> tz = timezone.utc |
| >>> repr(tz) |
| 'datetime.timezone.utc' |
| >>> tz = timezone(timedelta(hours=-5), 'EST') |
| >>> repr(tz) |
| "datetime.timezone(datetime.timedelta(-1, 68400), 'EST')" |
| """ |
| if self is self.utc: |
| return 'datetime.timezone.utc' |
| if self._name is None: |
| return "%s.%s(%r)" % (self.__class__.__module__, |
| self.__class__.__qualname__, |
| self._offset) |
| return "%s.%s(%r, %r)" % (self.__class__.__module__, |
| self.__class__.__qualname__, |
| self._offset, self._name) |
| |
| def __str__(self): |
| return self.tzname(None) |
| |
| def utcoffset(self, dt): |
| if isinstance(dt, datetime) or dt is None: |
| return self._offset |
| raise TypeError("utcoffset() argument must be a datetime instance" |
| " or None") |
| |
| def tzname(self, dt): |
| if isinstance(dt, datetime) or dt is None: |
| if self._name is None: |
| return self._name_from_offset(self._offset) |
| return self._name |
| raise TypeError("tzname() argument must be a datetime instance" |
| " or None") |
| |
| def dst(self, dt): |
| if isinstance(dt, datetime) or dt is None: |
| return None |
| raise TypeError("dst() argument must be a datetime instance" |
| " or None") |
| |
| def fromutc(self, dt): |
| if isinstance(dt, datetime): |
| if dt.tzinfo is not self: |
| raise ValueError("fromutc: dt.tzinfo " |
| "is not self") |
| return dt + self._offset |
| raise TypeError("fromutc() argument must be a datetime instance" |
| " or None") |
| |
| _maxoffset = timedelta(hours=23, minutes=59) |
| _minoffset = -_maxoffset |
| |
| @staticmethod |
| def _name_from_offset(delta): |
| if not delta: |
| return 'UTC' |
| if delta < timedelta(0): |
| sign = '-' |
| delta = -delta |
| else: |
| sign = '+' |
| hours, rest = divmod(delta, timedelta(hours=1)) |
| minutes, rest = divmod(rest, timedelta(minutes=1)) |
| seconds = rest.seconds |
| microseconds = rest.microseconds |
| if microseconds: |
| return (f'UTC{sign}{hours:02d}:{minutes:02d}:{seconds:02d}' |
| f'.{microseconds:06d}') |
| if seconds: |
| return f'UTC{sign}{hours:02d}:{minutes:02d}:{seconds:02d}' |
| return f'UTC{sign}{hours:02d}:{minutes:02d}' |
| |
| timezone.utc = timezone._create(timedelta(0)) |
| timezone.min = timezone._create(timezone._minoffset) |
| timezone.max = timezone._create(timezone._maxoffset) |
| _EPOCH = datetime(1970, 1, 1, tzinfo=timezone.utc) |
| |
| # Some time zone algebra. For a datetime x, let |
| # x.n = x stripped of its timezone -- its naive time. |
| # x.o = x.utcoffset(), and assuming that doesn't raise an exception or |
| # return None |
| # x.d = x.dst(), and assuming that doesn't raise an exception or |
| # return None |
| # x.s = x's standard offset, x.o - x.d |
| # |
| # Now some derived rules, where k is a duration (timedelta). |
| # |
| # 1. x.o = x.s + x.d |
| # This follows from the definition of x.s. |
| # |
| # 2. If x and y have the same tzinfo member, x.s = y.s. |
| # This is actually a requirement, an assumption we need to make about |
| # sane tzinfo classes. |
| # |
| # 3. The naive UTC time corresponding to x is x.n - x.o. |
| # This is again a requirement for a sane tzinfo class. |
| # |
| # 4. (x+k).s = x.s |
| # This follows from #2, and that datimetimetz+timedelta preserves tzinfo. |
| # |
| # 5. (x+k).n = x.n + k |
| # Again follows from how arithmetic is defined. |
| # |
| # Now we can explain tz.fromutc(x). Let's assume it's an interesting case |
| # (meaning that the various tzinfo methods exist, and don't blow up or return |
| # None when called). |
| # |
| # The function wants to return a datetime y with timezone tz, equivalent to x. |
| # x is already in UTC. |
| # |
| # By #3, we want |
| # |
| # y.n - y.o = x.n [1] |
| # |
| # The algorithm starts by attaching tz to x.n, and calling that y. So |
| # x.n = y.n at the start. Then it wants to add a duration k to y, so that [1] |
| # becomes true; in effect, we want to solve [2] for k: |
| # |
| # (y+k).n - (y+k).o = x.n [2] |
| # |
| # By #1, this is the same as |
| # |
| # (y+k).n - ((y+k).s + (y+k).d) = x.n [3] |
| # |
| # By #5, (y+k).n = y.n + k, which equals x.n + k because x.n=y.n at the start. |
| # Substituting that into [3], |
| # |
| # x.n + k - (y+k).s - (y+k).d = x.n; the x.n terms cancel, leaving |
| # k - (y+k).s - (y+k).d = 0; rearranging, |
| # k = (y+k).s - (y+k).d; by #4, (y+k).s == y.s, so |
| # k = y.s - (y+k).d |
| # |
| # On the RHS, (y+k).d can't be computed directly, but y.s can be, and we |
| # approximate k by ignoring the (y+k).d term at first. Note that k can't be |
| # very large, since all offset-returning methods return a duration of magnitude |
| # less than 24 hours. For that reason, if y is firmly in std time, (y+k).d must |
| # be 0, so ignoring it has no consequence then. |
| # |
| # In any case, the new value is |
| # |
| # z = y + y.s [4] |
| # |
| # It's helpful to step back at look at [4] from a higher level: it's simply |
| # mapping from UTC to tz's standard time. |
| # |
| # At this point, if |
| # |
| # z.n - z.o = x.n [5] |
| # |
| # we have an equivalent time, and are almost done. The insecurity here is |
| # at the start of daylight time. Picture US Eastern for concreteness. The wall |
| # time jumps from 1:59 to 3:00, and wall hours of the form 2:MM don't make good |
| # sense then. The docs ask that an Eastern tzinfo class consider such a time to |
| # be EDT (because it's "after 2"), which is a redundant spelling of 1:MM EST |
| # on the day DST starts. We want to return the 1:MM EST spelling because that's |
| # the only spelling that makes sense on the local wall clock. |
| # |
| # In fact, if [5] holds at this point, we do have the standard-time spelling, |
| # but that takes a bit of proof. We first prove a stronger result. What's the |
| # difference between the LHS and RHS of [5]? Let |
| # |
| # diff = x.n - (z.n - z.o) [6] |
| # |
| # Now |
| # z.n = by [4] |
| # (y + y.s).n = by #5 |
| # y.n + y.s = since y.n = x.n |
| # x.n + y.s = since z and y are have the same tzinfo member, |
| # y.s = z.s by #2 |
| # x.n + z.s |
| # |
| # Plugging that back into [6] gives |
| # |
| # diff = |
| # x.n - ((x.n + z.s) - z.o) = expanding |
| # x.n - x.n - z.s + z.o = cancelling |
| # - z.s + z.o = by #2 |
| # z.d |
| # |
| # So diff = z.d. |
| # |
| # If [5] is true now, diff = 0, so z.d = 0 too, and we have the standard-time |
| # spelling we wanted in the endcase described above. We're done. Contrarily, |
| # if z.d = 0, then we have a UTC equivalent, and are also done. |
| # |
| # If [5] is not true now, diff = z.d != 0, and z.d is the offset we need to |
| # add to z (in effect, z is in tz's standard time, and we need to shift the |
| # local clock into tz's daylight time). |
| # |
| # Let |
| # |
| # z' = z + z.d = z + diff [7] |
| # |
| # and we can again ask whether |
| # |
| # z'.n - z'.o = x.n [8] |
| # |
| # If so, we're done. If not, the tzinfo class is insane, according to the |
| # assumptions we've made. This also requires a bit of proof. As before, let's |
| # compute the difference between the LHS and RHS of [8] (and skipping some of |
| # the justifications for the kinds of substitutions we've done several times |
| # already): |
| # |
| # diff' = x.n - (z'.n - z'.o) = replacing z'.n via [7] |
| # x.n - (z.n + diff - z'.o) = replacing diff via [6] |
| # x.n - (z.n + x.n - (z.n - z.o) - z'.o) = |
| # x.n - z.n - x.n + z.n - z.o + z'.o = cancel x.n |
| # - z.n + z.n - z.o + z'.o = cancel z.n |
| # - z.o + z'.o = #1 twice |
| # -z.s - z.d + z'.s + z'.d = z and z' have same tzinfo |
| # z'.d - z.d |
| # |
| # So z' is UTC-equivalent to x iff z'.d = z.d at this point. If they are equal, |
| # we've found the UTC-equivalent so are done. In fact, we stop with [7] and |
| # return z', not bothering to compute z'.d. |
| # |
| # How could z.d and z'd differ? z' = z + z.d [7], so merely moving z' by |
| # a dst() offset, and starting *from* a time already in DST (we know z.d != 0), |
| # would have to change the result dst() returns: we start in DST, and moving |
| # a little further into it takes us out of DST. |
| # |
| # There isn't a sane case where this can happen. The closest it gets is at |
| # the end of DST, where there's an hour in UTC with no spelling in a hybrid |
| # tzinfo class. In US Eastern, that's 5:MM UTC = 0:MM EST = 1:MM EDT. During |
| # that hour, on an Eastern clock 1:MM is taken as being in standard time (6:MM |
| # UTC) because the docs insist on that, but 0:MM is taken as being in daylight |
| # time (4:MM UTC). There is no local time mapping to 5:MM UTC. The local |
| # clock jumps from 1:59 back to 1:00 again, and repeats the 1:MM hour in |
| # standard time. Since that's what the local clock *does*, we want to map both |
| # UTC hours 5:MM and 6:MM to 1:MM Eastern. The result is ambiguous |
| # in local time, but so it goes -- it's the way the local clock works. |
| # |
| # When x = 5:MM UTC is the input to this algorithm, x.o=0, y.o=-5 and y.d=0, |
| # so z=0:MM. z.d=60 (minutes) then, so [5] doesn't hold and we keep going. |
| # z' = z + z.d = 1:MM then, and z'.d=0, and z'.d - z.d = -60 != 0 so [8] |
| # (correctly) concludes that z' is not UTC-equivalent to x. |
| # |
| # Because we know z.d said z was in daylight time (else [5] would have held and |
| # we would have stopped then), and we know z.d != z'.d (else [8] would have held |
| # and we have stopped then), and there are only 2 possible values dst() can |
| # return in Eastern, it follows that z'.d must be 0 (which it is in the example, |
| # but the reasoning doesn't depend on the example -- it depends on there being |
| # two possible dst() outcomes, one zero and the other non-zero). Therefore |
| # z' must be in standard time, and is the spelling we want in this case. |
| # |
| # Note again that z' is not UTC-equivalent as far as the hybrid tzinfo class is |
| # concerned (because it takes z' as being in standard time rather than the |
| # daylight time we intend here), but returning it gives the real-life "local |
| # clock repeats an hour" behavior when mapping the "unspellable" UTC hour into |
| # tz. |
| # |
| # When the input is 6:MM, z=1:MM and z.d=0, and we stop at once, again with |
| # the 1:MM standard time spelling we want. |
| # |
| # So how can this break? One of the assumptions must be violated. Two |
| # possibilities: |
| # |
| # 1) [2] effectively says that y.s is invariant across all y belong to a given |
| # time zone. This isn't true if, for political reasons or continental drift, |
| # a region decides to change its base offset from UTC. |
| # |
| # 2) There may be versions of "double daylight" time where the tail end of |
| # the analysis gives up a step too early. I haven't thought about that |
| # enough to say. |
| # |
| # In any case, it's clear that the default fromutc() is strong enough to handle |
| # "almost all" time zones: so long as the standard offset is invariant, it |
| # doesn't matter if daylight time transition points change from year to year, or |
| # if daylight time is skipped in some years; it doesn't matter how large or |
| # small dst() may get within its bounds; and it doesn't even matter if some |
| # perverse time zone returns a negative dst()). So a breaking case must be |
| # pretty bizarre, and a tzinfo subclass can override fromutc() if it is. |
| |
| try: |
| from _datetime import * |
| except ImportError: |
| pass |
| else: |
| # Clean up unused names |
| del (_DAYNAMES, _DAYS_BEFORE_MONTH, _DAYS_IN_MONTH, _DI100Y, _DI400Y, |
| _DI4Y, _EPOCH, _MAXORDINAL, _MONTHNAMES, _build_struct_time, |
| _check_date_fields, _check_int_field, _check_time_fields, |
| _check_tzinfo_arg, _check_tzname, _check_utc_offset, _cmp, _cmperror, |
| _date_class, _days_before_month, _days_before_year, _days_in_month, |
| _format_time, _format_offset, _is_leap, _isoweek1monday, _math, |
| _ord2ymd, _time, _time_class, _tzinfo_class, _wrap_strftime, _ymd2ord, |
| _divide_and_round, _parse_isoformat_date, _parse_isoformat_time, |
| _parse_hh_mm_ss_ff) |
| # XXX Since import * above excludes names that start with _, |
| # docstring does not get overwritten. In the future, it may be |
| # appropriate to maintain a single module level docstring and |
| # remove the following line. |
| from _datetime import __doc__ |