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Diffstat (limited to '.venv/lib/python3.12/site-packages/isodate/isodates.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/isodate/isodates.py | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/isodate/isodates.py b/.venv/lib/python3.12/site-packages/isodate/isodates.py new file mode 100644 index 00000000..d32fe25e --- /dev/null +++ b/.venv/lib/python3.12/site-packages/isodate/isodates.py @@ -0,0 +1,203 @@ +""" +This modules provides a method to parse an ISO 8601:2004 date string to a +python datetime.date instance. + +It supports all basic, extended and expanded formats as described in the ISO +standard. The only limitations it has, are given by the Python datetime.date +implementation, which does not support dates before 0001-01-01. +""" + +import re +from datetime import date, timedelta + +from isodate.isoerror import ISO8601Error +from isodate.isostrf import DATE_EXT_COMPLETE, strftime + +DATE_REGEX_CACHE = {} +# A dictionary to cache pre-compiled regular expressions. +# A set of regular expressions is identified, by number of year digits allowed +# and whether a plus/minus sign is required or not. (This option is changeable +# only for 4 digit years). + + +def build_date_regexps(yeardigits=4, expanded=False): + """ + Compile set of regular expressions to parse ISO dates. The expressions will + be created only if they are not already in REGEX_CACHE. + + It is necessary to fix the number of year digits, else it is not possible + to automatically distinguish between various ISO date formats. + + ISO 8601 allows more than 4 digit years, on prior agreement, but then a +/- + sign is required (expanded format). To support +/- sign for 4 digit years, + the expanded parameter needs to be set to True. + """ + if yeardigits != 4: + expanded = True + if (yeardigits, expanded) not in DATE_REGEX_CACHE: + cache_entry = [] + # ISO 8601 expanded DATE formats allow an arbitrary number of year + # digits with a leading +/- sign. + if expanded: + sign = 1 + else: + sign = 0 + + def add_re(regex_text): + cache_entry.append(re.compile(r"\A" + regex_text + r"\Z")) + + # 1. complete dates: + # YYYY-MM-DD or +- YYYYYY-MM-DD... extended date format + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"-(?P<month>[0-9]{2})-(?P<day>[0-9]{2})" % (sign, yeardigits) + ) + # YYYYMMDD or +- YYYYYYMMDD... basic date format + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"(?P<month>[0-9]{2})(?P<day>[0-9]{2})" % (sign, yeardigits) + ) + # 2. complete week dates: + # YYYY-Www-D or +-YYYYYY-Www-D ... extended week date + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"-W(?P<week>[0-9]{2})-(?P<day>[0-9]{1})" % (sign, yeardigits) + ) + # YYYYWwwD or +-YYYYYYWwwD ... basic week date + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})W" + r"(?P<week>[0-9]{2})(?P<day>[0-9]{1})" % (sign, yeardigits) + ) + # 3. ordinal dates: + # YYYY-DDD or +-YYYYYY-DDD ... extended format + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"-(?P<day>[0-9]{3})" % (sign, yeardigits) + ) + # YYYYDDD or +-YYYYYYDDD ... basic format + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"(?P<day>[0-9]{3})" % (sign, yeardigits) + ) + # 4. week dates: + # YYYY-Www or +-YYYYYY-Www ... extended reduced accuracy week date + # 4. week dates: + # YYYY-Www or +-YYYYYY-Www ... extended reduced accuracy week date + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"-W(?P<week>[0-9]{2})" % (sign, yeardigits) + ) + # YYYYWww or +-YYYYYYWww ... basic reduced accuracy week date + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})W" + r"(?P<week>[0-9]{2})" % (sign, yeardigits) + ) + # 5. month dates: + # YYY-MM or +-YYYYYY-MM ... reduced accuracy specific month + # 5. month dates: + # YYY-MM or +-YYYYYY-MM ... reduced accuracy specific month + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"-(?P<month>[0-9]{2})" % (sign, yeardigits) + ) + # YYYMM or +-YYYYYYMM ... basic incomplete month date format + add_re( + r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" + r"(?P<month>[0-9]{2})" % (sign, yeardigits) + ) + # 6. year dates: + # YYYY or +-YYYYYY ... reduced accuracy specific year + add_re(r"(?P<sign>[+-]){%d}(?P<year>[0-9]{%d})" % (sign, yeardigits)) + # 7. century dates: + # YY or +-YYYY ... reduced accuracy specific century + add_re(r"(?P<sign>[+-]){%d}" r"(?P<century>[0-9]{%d})" % (sign, yeardigits - 2)) + + DATE_REGEX_CACHE[(yeardigits, expanded)] = cache_entry + return DATE_REGEX_CACHE[(yeardigits, expanded)] + + +def parse_date(datestring, yeardigits=4, expanded=False, defaultmonth=1, defaultday=1): + """ + Parse an ISO 8601 date string into a datetime.date object. + + As the datetime.date implementation is limited to dates starting from + 0001-01-01, negative dates (BC) and year 0 can not be parsed by this + method. + + For incomplete dates, this method chooses the first day for it. For + instance if only a century is given, this method returns the 1st of + January in year 1 of this century. + + supported formats: (expanded formats are shown with 6 digits for year) + YYYYMMDD +-YYYYYYMMDD basic complete date + YYYY-MM-DD +-YYYYYY-MM-DD extended complete date + YYYYWwwD +-YYYYYYWwwD basic complete week date + YYYY-Www-D +-YYYYYY-Www-D extended complete week date + YYYYDDD +-YYYYYYDDD basic ordinal date + YYYY-DDD +-YYYYYY-DDD extended ordinal date + YYYYWww +-YYYYYYWww basic incomplete week date + YYYY-Www +-YYYYYY-Www extended incomplete week date + YYYMM +-YYYYYYMM basic incomplete month date + YYY-MM +-YYYYYY-MM incomplete month date + YYYY +-YYYYYY incomplete year date + YY +-YYYY incomplete century date + + @param datestring: the ISO date string to parse + @param yeardigits: how many digits are used to represent a year + @param expanded: if True then +/- signs are allowed. This parameter + is forced to True, if yeardigits != 4 + + @return: a datetime.date instance represented by datestring + @raise ISO8601Error: if this function can not parse the datestring + @raise ValueError: if datestring can not be represented by datetime.date + """ + if yeardigits != 4: + expanded = True + isodates = build_date_regexps(yeardigits, expanded) + for pattern in isodates: + match = pattern.match(datestring) + if match: + groups = match.groupdict() + # sign, century, year, month, week, day, + # FIXME: negative dates not possible with python standard types + sign = (groups["sign"] == "-" and -1) or 1 + if "century" in groups: + return date( + sign * (int(groups["century"]) * 100 + 1), defaultmonth, defaultday + ) + if "month" not in groups: # weekdate or ordinal date + ret = date(sign * int(groups["year"]), 1, 1) + if "week" in groups: + isotuple = ret.isocalendar() + if "day" in groups: + days = int(groups["day"] or 1) + else: + days = 1 + # if first week in year, do weeks-1 + return ret + timedelta( + weeks=int(groups["week"]) - (((isotuple[1] == 1) and 1) or 0), + days=-isotuple[2] + days, + ) + elif "day" in groups: # ordinal date + return ret + timedelta(days=int(groups["day"]) - 1) + else: # year date + return ret.replace(month=defaultmonth, day=defaultday) + # year-, month-, or complete date + if "day" not in groups or groups["day"] is None: + day = defaultday + else: + day = int(groups["day"]) + return date( + sign * int(groups["year"]), int(groups["month"]) or defaultmonth, day + ) + raise ISO8601Error("Unrecognised ISO 8601 date format: %r" % datestring) + + +def date_isoformat(tdate, format=DATE_EXT_COMPLETE, yeardigits=4): + """ + Format date strings. + + This method is just a wrapper around isodate.isostrf.strftime and uses + Date-Extended-Complete as default format. + """ + return strftime(tdate, format, yeardigits) |