Added pattern representation for parse() error messagesmonolithic-zope3-3.3

1 files changed, 893 insertions, 0 deletions

diff --git a/format.py b/format.py
new file mode 100644
index 0000000..a7e7b7a
--- /dev/null
+++ b/format.py
@@ -0,0 +1,893 @@
+##############################################################################
+#
+# Copyright (c) 2002, 2003 Zope Corporation and Contributors.
+# All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
+# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+# FOR A PARTICULAR PURPOSE.
+#
+##############################################################################
+"""Basic Object Formatting
+
+This module implements basic object formatting functionality, such as
+date/time, number and money formatting.
+
+$Id$
+"""
+import re
+import math
+import datetime
+import pytz
+import pytz.reference
+
+from zope.i18n.interfaces import IDateTimeFormat, INumberFormat
+from zope.interface import implements
+
+
+def _findFormattingCharacterInPattern(char, pattern):
+    return [entry for entry in pattern
+            if isinstance(entry, tuple) and entry[0] == char]
+
+class DateTimeParseError(Exception):
+    """Error is raised when parsing of datetime failed."""
+
+class DateTimeFormat(object):
+    __doc__ = IDateTimeFormat.__doc__
+
+    implements(IDateTimeFormat)
+
+    _DATETIMECHARS = "aGyMdEDFwWhHmsSkKz"
+
+    def __init__(self, pattern=None, calendar=None):
+        if calendar is not None:
+            self.calendar = calendar
+        self._pattern = pattern
+        self._bin_pattern = None
+        if self._pattern is not None:
+            self._bin_pattern = parseDateTimePattern(self._pattern,
+                                                     self._DATETIMECHARS)
+
+    def setPattern(self, pattern):
+        "See zope.i18n.interfaces.IFormat"
+        self._pattern = pattern
+        self._bin_pattern = parseDateTimePattern(self._pattern,
+                                                 self._DATETIMECHARS)
+
+    def getPattern(self):
+        "See zope.i18n.interfaces.IFormat"
+        return self._pattern
+
+    def parse(self, text, pattern=None, asObject=True):
+        "See zope.i18n.interfaces.IFormat"
+        # Make or get binary form of datetime pattern
+        if pattern is not None:
+            bin_pattern = parseDateTimePattern(pattern)
+        else:
+            bin_pattern = self._bin_pattern
+            pattern = self._pattern
+
+        # Generate the correct regular expression to parse the date and parse.
+        regex = ''
+        info = buildDateTimeParseInfo(self.calendar, bin_pattern)
+        for elem in bin_pattern:
+            regex += info.get(elem, elem)
+        try:
+            results = re.match(regex, text).groups()
+        except AttributeError:
+            raise DateTimeParseError(
+                  'The datetime string did not match the pattern %r.'
+                  % pattern)
+        # Sometimes you only want the parse results
+        if not asObject:
+            return results
+
+        # Map the parsing results to a datetime object
+        ordered = [None, None, None, None, None, None, None]
+        bin_pattern = filter(lambda x: isinstance(x, tuple), bin_pattern)
+
+        # Handle years; note that only 'yy' and 'yyyy' are allowed
+        if ('y', 2) in bin_pattern:
+            year = int(results[bin_pattern.index(('y', 2))])
+            if year > 30:
+                ordered[0] = 1900 + year
+            else:
+                ordered[0] = 2000 + year
+        if ('y', 4) in bin_pattern:
+            ordered[0] = int(results[bin_pattern.index(('y', 4))])
+
+        # Handle months (text)
+        month_entry = _findFormattingCharacterInPattern('M', bin_pattern)
+        if month_entry and month_entry[0][1] == 3:
+            abbr = results[bin_pattern.index(month_entry[0])]
+            ordered[1] = self.calendar.getMonthTypeFromAbbreviation(abbr)
+        elif month_entry and month_entry[0][1] >= 4:
+            name = results[bin_pattern.index(month_entry[0])]
+            ordered[1] = self.calendar.getMonthTypeFromName(name)
+        elif month_entry and month_entry[0][1] <= 2:
+            ordered[1] = int(results[bin_pattern.index(month_entry[0])])
+
+        # Handle hours with AM/PM
+        hour_entry = _findFormattingCharacterInPattern('h', bin_pattern)
+        if hour_entry:
+            hour = int(results[bin_pattern.index(hour_entry[0])])
+            ampm_entry = _findFormattingCharacterInPattern('a', bin_pattern)
+            if not ampm_entry:
+                raise DateTimeParseError(
+                      'Cannot handle 12-hour format without am/pm marker.')
+            ampm = self.calendar.pm == results[bin_pattern.index(ampm_entry[0])]
+            if hour == 12:
+                ampm = not ampm
+            ordered[3] = (hour + 12*ampm)%24
+
+        # Shortcut for the simple int functions
+        dt_fields_map = {'d': 2, 'H': 3, 'm': 4, 's': 5, 'S': 6}
+        for field in dt_fields_map.keys():
+            entry = _findFormattingCharacterInPattern(field, bin_pattern)
+            if not entry: continue
+            pos = dt_fields_map[field]
+            ordered[pos] = int(results[bin_pattern.index(entry[0])])
+
+        # Handle timezones
+        tzinfo = None
+        pytz_tzinfo = False # If True, we should use pytz specific syntax
+        tz_entry = _findFormattingCharacterInPattern('z', bin_pattern)
+        if ordered[3:] != [None, None, None, None] and tz_entry:
+            length = tz_entry[0][1]
+            value = results[bin_pattern.index(tz_entry[0])]
+            if length == 1:
+                hours, mins = int(value[:-2]), int(value[-2:])
+                tzinfo = pytz.FixedOffset(hours * 60 + mins)
+            elif length == 2:
+                hours, mins = int(value[:-3]), int(value[-2:])
+                tzinfo = pytz.FixedOffset(hours * 60 + mins)
+            else:
+                try:
+                    tzinfo = pytz.timezone(value)
+                    pytz_tzinfo = True
+                except KeyError:
+                    # TODO: Find timezones using locale information
+                    pass
+
+        # Create a date/time object from the data
+        # If we have a pytz tzinfo, we need to invoke localize() as per
+        # the pytz documentation on creating local times.
+        # NB. If we are in an end-of-DST transition period, we have a 50%
+        # chance of getting a time 1 hour out here, but that is the price
+        # paid for dealing with localtimes.
+        if ordered[3:] == [None, None, None, None]:
+            return datetime.date(*[e or 0 for e in ordered[:3]])
+        elif ordered[:3] == [None, None, None]:
+            if pytz_tzinfo:
+                return tzinfo.localize(
+                    datetime.time(*[e or 0 for e in ordered[3:]])
+                    )
+            else:
+                return datetime.time(
+                    *[e or 0 for e in ordered[3:]], **{'tzinfo' :tzinfo}
+                    )
+        else:
+            if pytz_tzinfo:
+                return tzinfo.localize(datetime.datetime(
+                    *[e or 0 for e in ordered]
+                    ))
+            else:
+                return datetime.datetime(
+                    *[e or 0 for e in ordered], **{'tzinfo' :tzinfo}
+                    )
+
+    def format(self, obj, pattern=None):
+        "See zope.i18n.interfaces.IFormat"
+        # Make or get binary form of datetime pattern
+        if pattern is not None:
+            bin_pattern = parseDateTimePattern(pattern)
+        else:
+            bin_pattern = self._bin_pattern
+
+        text = u''
+        info = buildDateTimeInfo(obj, self.calendar, bin_pattern)
+        for elem in bin_pattern:
+            text += info.get(elem, elem)
+
+        return text
+
+
+class NumberParseError(Exception):
+    """Error that can be raised when smething unexpected happens during the
+    number parsing process."""
+
+
+class NumberFormat(object):
+    __doc__ = INumberFormat.__doc__
+
+    implements(INumberFormat)
+
+    def __init__(self, pattern=None, symbols={}):
+        # setup default symbols
+        self.symbols = {
+            u'decimal': u'.',
+            u'group': u',',
+            u'list':  u';',
+            u'percentSign': u'%',
+            u'nativeZeroDigit': u'0',
+            u'patternDigit': u'#',
+            u'plusSign': u'+',
+            u'minusSign': u'-',
+            u'exponential': u'E',
+            u'perMille': u'\xe2\x88\x9e',
+            u'infinity': u'\xef\xbf\xbd',
+            u'nan': '' }
+        self.symbols.update(symbols)
+        self._pattern = pattern
+        self._bin_pattern = None
+        if self._pattern is not None:
+            self._bin_pattern = parseNumberPattern(self._pattern)
+
+    def setPattern(self, pattern):
+        "See zope.i18n.interfaces.IFormat"
+        self._pattern = pattern
+        self._bin_pattern = parseNumberPattern(self._pattern)
+
+    def getPattern(self):
+        "See zope.i18n.interfaces.IFormat"
+        return self._pattern
+
+    def parse(self, text, pattern=None):
+        "See zope.i18n.interfaces.IFormat"
+        # Make or get binary form of datetime pattern
+        if pattern is not None:
+            bin_pattern = parseNumberPattern(pattern)
+        else:
+            bin_pattern = self._bin_pattern
+            pattern = self._pattern
+        # Determine sign
+        num_res = [None, None]
+        for sign in (0, 1):
+            regex = ''
+            if bin_pattern[sign][PADDING1] is not None:
+                regex += '[' + bin_pattern[sign][PADDING1] + ']+'
+            if bin_pattern[sign][PREFIX] != '':
+                regex += '[' + bin_pattern[sign][PREFIX] + ']'
+            if bin_pattern[sign][PADDING2] is not None:
+                regex += '[' + bin_pattern[sign][PADDING2] + ']+'
+            regex += '([0-9'
+            min_size = bin_pattern[sign][INTEGER].count('0')
+            if bin_pattern[sign][GROUPING]:
+                regex += self.symbols['group']
+                min_size += min_size/3
+            regex += ']{%i,100}' %(min_size)
+            if bin_pattern[sign][FRACTION]:
+                max_precision = len(bin_pattern[sign][FRACTION])
+                min_precision = bin_pattern[sign][FRACTION].count('0')
+                regex += '['+self.symbols['decimal']+']'
+                regex += '[0-9]{%i,%i}' %(min_precision, max_precision)
+            if bin_pattern[sign][EXPONENTIAL] != '':
+                regex += self.symbols['exponential']
+                min_exp_size = bin_pattern[sign][EXPONENTIAL].count('0')
+                pre_symbols = self.symbols['minusSign']
+                if bin_pattern[sign][EXPONENTIAL][0] == '+':
+                    pre_symbols += self.symbols['plusSign']
+                regex += '[%s]?[0-9]{%i,100}' %(pre_symbols, min_exp_size)
+            regex +=')'
+            if bin_pattern[sign][PADDING3] is not None:
+                regex += '[' + bin_pattern[sign][PADDING3] + ']+'
+            if bin_pattern[sign][SUFFIX] != '':
+                regex += '[' + bin_pattern[sign][SUFFIX] + ']'
+            if bin_pattern[sign][PADDING4] is not None:
+                regex += '[' + bin_pattern[sign][PADDING4] + ']+'
+            num_res[sign] = re.match(regex, text)
+
+        if num_res[0] is not None:
+            num_str = num_res[0].groups()[0]
+            sign = +1
+        elif num_res[1] is not None:
+            num_str = num_res[1].groups()[0]
+            sign = -1
+        else:
+            raise NumberParseError('Not a valid number for this pattern %r.'
+                                    % pattern)
+        # Remove possible grouping separators
+        num_str = num_str.replace(self.symbols['group'], '')
+        # Extract number
+        type = int
+        if self.symbols['decimal'] in num_str:
+            type = float
+            num_str = num_str.replace(self.symbols['decimal'], '.')
+        if self.symbols['exponential'] in num_str:
+            type = float
+            num_str = num_str.replace(self.symbols['exponential'], 'E')
+        return sign*type(num_str)
+
+    def _format_integer(self, integer, pattern):
+        size = len(integer)
+        min_size = pattern.count('0')
+        if size < min_size:
+            integer = self.symbols['nativeZeroDigit']*(min_size-size) + integer
+        return integer
+
+    def _format_fraction(self, fraction, pattern):
+        max_precision = len(pattern)
+        min_precision = pattern.count('0')
+        precision = len(fraction)
+        roundInt = False
+        if precision > max_precision:
+            round = int(fraction[max_precision]) >= 5
+            fraction = fraction[:max_precision]
+            if round:
+                if fraction != '':
+                    # add 1 to the fraction, maintaining the decimal
+                    # precision; if the result >= 1, need to roundInt
+                    fractionLen = len(fraction)
+                    rounded = int(fraction) + 1
+                    fraction = ('%0' + str(fractionLen) + 'i') % rounded
+                    if len(fraction) > fractionLen:	# rounded fraction >= 1
+                        roundInt = True
+                        fraction = fraction[1:]
+                else:
+                    # fraction missing, e.g. 1.5 -> 1. -- need to roundInt
+                    roundInt = True
+
+        if precision < min_precision:
+            fraction += self.symbols['nativeZeroDigit']*(min_precision -
+                                                         precision)
+        if fraction != '':
+            fraction = self.symbols['decimal'] + fraction
+        return fraction, roundInt
+
+    def format(self, obj, pattern=None):
+        "See zope.i18n.interfaces.IFormat"
+        # Make or get binary form of datetime pattern
+        if pattern is not None:
+            bin_pattern = parseNumberPattern(pattern)
+        else:
+            bin_pattern = self._bin_pattern
+        # Get positive or negative sub-pattern
+        if obj >= 0:
+            bin_pattern = bin_pattern[0]
+        else:
+            bin_pattern = bin_pattern[1]
+
+
+        if bin_pattern[EXPONENTIAL] != '':
+            obj_int_frac = str(obj).split('.')
+            # The exponential might have a mandatory sign; remove it from the
+            # bin_pattern and remember the setting
+            exp_bin_pattern = bin_pattern[EXPONENTIAL]
+            plus_sign = u''
+            if exp_bin_pattern.startswith('+'):
+                plus_sign = self.symbols['plusSign']
+                exp_bin_pattern = exp_bin_pattern[1:]
+            # We have to remove the possible '-' sign
+            if obj < 0:
+                obj_int_frac[0] = obj_int_frac[0][1:]
+            if obj_int_frac[0] == '0':
+                # abs() of number smaller 1
+                if len(obj_int_frac) > 1:
+                    res = re.match('(0*)[0-9]*', obj_int_frac[1]).groups()[0]
+                    exponent = self._format_integer(str(len(res)+1),
+                                                    exp_bin_pattern)
+                    exponent = self.symbols['minusSign']+exponent
+                    number = obj_int_frac[1][len(res):]
+                else:
+                    # We have exactly 0
+                    exponent = self._format_integer('0', exp_bin_pattern)
+                    number = self.symbols['nativeZeroDigit']
+            else:
+                exponent = self._format_integer(str(len(obj_int_frac[0])-1),
+                                                exp_bin_pattern)
+                number = ''.join(obj_int_frac)
+
+            fraction, roundInt = self._format_fraction(number[1:],
+                                                       bin_pattern[FRACTION])
+            if roundInt:
+                number = str(int(number[0]) + 1) + fraction
+            else:
+                number = number[0] + fraction
+
+            # We might have a plus sign in front of the exponential integer
+            if not exponent.startswith('-'):
+                exponent = plus_sign + exponent
+
+            pre_padding = len(bin_pattern[FRACTION]) - len(number) + 2
+            post_padding = len(exp_bin_pattern) - len(exponent)
+            number += self.symbols['exponential'] + exponent
+
+        else:
+            obj_int_frac = str(obj).split('.')
+            if len(obj_int_frac) > 1:
+                fraction, roundInt = self._format_fraction(obj_int_frac[1],
+                                                 bin_pattern[FRACTION])
+            else:
+                fraction = ''
+                roundInt = False
+            if roundInt:
+                obj = round(obj)
+            integer = self._format_integer(str(int(math.fabs(obj))),
+                                           bin_pattern[INTEGER])
+            # Adding grouping
+            if bin_pattern[GROUPING] == 1:
+                help = ''
+                for pos in range(1, len(integer)+1):
+                    if (pos-1)%3 == 0 and pos != 1:
+                        help = self.symbols['group'] + help
+                    help = integer[-pos] + help
+                integer = help
+            pre_padding = len(bin_pattern[INTEGER]) - len(integer)
+            post_padding = len(bin_pattern[FRACTION]) - len(fraction)+1
+            number = integer + fraction
+
+        # Put it all together
+        text = ''
+        if bin_pattern[PADDING1] is not None and pre_padding > 0:
+            text += bin_pattern[PADDING1]*pre_padding
+        text += bin_pattern[PREFIX]
+        if bin_pattern[PADDING2] is not None and pre_padding > 0:
+            if bin_pattern[PADDING1] is not None:
+                text += bin_pattern[PADDING2]
+            else:
+                text += bin_pattern[PADDING2]*pre_padding
+        text += number
+        if bin_pattern[PADDING3] is not None and post_padding > 0:
+            if bin_pattern[PADDING4] is not None:
+                text += bin_pattern[PADDING3]
+            else:
+                text += bin_pattern[PADDING3]*post_padding
+        text += bin_pattern[SUFFIX]
+        if bin_pattern[PADDING4] is not None and post_padding > 0:
+            text += bin_pattern[PADDING4]*post_padding
+
+        # TODO: Need to make sure unicode is everywhere
+        return unicode(text)
+
+
+
+DEFAULT = 0
+IN_QUOTE = 1
+IN_DATETIMEFIELD = 2
+
+class DateTimePatternParseError(Exception):
+    """DateTime Pattern Parse Error"""
+
+
+def parseDateTimePattern(pattern, DATETIMECHARS="aGyMdEDFwWhHmsSkKz"):
+    """This method can handle everything: time, date and datetime strings."""
+    result = []
+    state = DEFAULT
+    helper = ''
+    char = ''
+    quote_start = -2
+
+    for pos in range(len(pattern)):
+        prev_char = char
+        char = pattern[pos]
+        # Handle quotations
+        if char == "'":
+            if state == DEFAULT:
+                quote_start = pos
+                state = IN_QUOTE
+            elif state == IN_QUOTE and prev_char == "'":
+                helper += char
+                state = DEFAULT
+            elif state == IN_QUOTE:
+                # Do not care about putting the content of the quote in the
+                # result. The next state is responsible for that.
+                quote_start = -1
+                state = DEFAULT
+            elif state == IN_DATETIMEFIELD:
+                result.append((helper[0], len(helper)))
+                helper = ''
+                quote_start = pos
+                state = IN_QUOTE
+        elif state == IN_QUOTE:
+            helper += char
+
+        # Handle regular characters
+        elif char not in DATETIMECHARS:
+            if state == IN_DATETIMEFIELD:
+                result.append((helper[0], len(helper)))
+                helper = char
+                state = DEFAULT
+            elif state == DEFAULT:
+                helper += char
+
+        # Handle special formatting characters
+        elif char in DATETIMECHARS:
+            if state == DEFAULT:
+                # Clean up helper first
+                if helper:
+                    result.append(helper)
+                helper = char
+                state = IN_DATETIMEFIELD
+
+            elif state == IN_DATETIMEFIELD and prev_char == char:
+                helper += char
+
+            elif state == IN_DATETIMEFIELD and prev_char != char:
+                result.append((helper[0], len(helper)))
+                helper = char
+
+    # Some cleaning up
+    if state == IN_QUOTE:
+        if quote_start == -1:
+            raise DateTimePatternParseError(
+                  'Waaa: state = IN_QUOTE and quote_start = -1!')
+        else:
+            raise DateTimePatternParseError(
+                  'The quote starting at character %i is not closed.' %
+                   quote_start)
+    elif state == IN_DATETIMEFIELD:
+        result.append((helper[0], len(helper)))
+    elif state == DEFAULT:
+        result.append(helper)
+
+    return result
+
+
+def buildDateTimeParseInfo(calendar, pattern):
+    """This method returns a dictionary that helps us with the parsing.
+    It also depends on the locale of course."""
+    info = {}
+    # Generic Numbers
+    for field in 'dDFkKhHmsSwW':
+        for entry in _findFormattingCharacterInPattern(field, pattern):
+            # The maximum amount of digits should be infinity, but 1000 is
+            # close enough here.
+            info[entry] = r'([0-9]{%i,1000})' %entry[1]
+
+    # year (Number)
+    for entry in _findFormattingCharacterInPattern('y', pattern):
+        if entry[1] == 2:
+            info[entry] = r'([0-9]{2})'
+        elif entry[1] == 4:
+            info[entry] = r'([0-9]{4})'
+        else:
+            raise DateTimePatternParseError("Only 'yy' and 'yyyy' allowed." )
+
+    # am/pm marker (Text)
+    for entry in _findFormattingCharacterInPattern('a', pattern):
+        info[entry] = r'(%s|%s)' %(calendar.am, calendar.pm)
+
+    # era designator (Text)
+    # TODO: works for gregorian only right now
+    for entry in _findFormattingCharacterInPattern('G', pattern):
+        info[entry] = r'(%s|%s)' %(calendar.eras[1][1], calendar.eras[2][1])
+
+    # time zone (Text)
+    for entry in _findFormattingCharacterInPattern('z', pattern):
+        if entry[1] == 1:
+            info[entry] = r'([\+-][0-9]{3,4})'
+        elif entry[1] == 2:
+            info[entry] = r'([\+-][0-9]{2}:[0-9]{2})'
+        elif entry[1] == 3:
+            info[entry] = r'([a-zA-Z]{3})'
+        else:
+            info[entry] = r'([a-zA-Z /\.]*)'
+
+    # month in year (Text and Number)
+    for entry in _findFormattingCharacterInPattern('M', pattern):
+        if entry[1] == 1:
+            info[entry] = r'([0-9]{1,2})'
+        elif entry[1] == 2:
+            info[entry] = r'([0-9]{2})'
+        elif entry[1] == 3:
+            info[entry] = r'('+'|'.join(calendar.getMonthAbbreviations())+')'
+        else:
+            info[entry] = r'('+'|'.join(calendar.getMonthNames())+')'
+
+    # day in week (Text and Number)
+    for entry in _findFormattingCharacterInPattern('E', pattern):
+        if entry[1] == 1:
+            info[entry] = r'([0-9])'
+        elif entry[1] == 2:
+            info[entry] = r'([0-9]{2})'
+        elif entry[1] == 3:
+            info[entry] = r'('+'|'.join(calendar.getDayAbbreviations())+')'
+        else:
+            info[entry] = r'('+'|'.join(calendar.getDayNames())+')'
+
+    return info
+
+
+def buildDateTimeInfo(dt, calendar, pattern):
+    """Create the bits and pieces of the datetime object that can be put
+    together."""
+    if isinstance(dt, datetime.time):
+        dt = datetime.datetime(1969, 01, 01, dt.hour, dt.minute, dt.second,
+                               dt.microsecond)
+    elif (isinstance(dt, datetime.date) and
+          not isinstance(dt, datetime.datetime)):
+        dt = datetime.datetime(dt.year, dt.month, dt.day)
+
+    if dt.hour >= 12:
+        ampm = calendar.pm
+    else:
+        ampm = calendar.am
+
+    h = dt.hour%12
+    if h == 0:
+        h = 12
+
+    weekday = (dt.weekday() + (8 - calendar.week['firstDay'])) % 7 + 1
+
+    day_of_week_in_month = (dt.day - 1) / 7 + 1
+
+    week_in_month = (dt.day + 6 - dt.weekday()) / 7 + 1
+
+    # Getting the timezone right
+    tzinfo = dt.tzinfo or pytz.utc
+    tz_secs = tzinfo.utcoffset(dt).seconds
+    tz_secs = (tz_secs > 12*3600) and tz_secs-24*3600 or tz_secs
+    tz_mins = int(math.fabs(tz_secs % 3600 / 60))
+    tz_hours = int(math.fabs(tz_secs / 3600))
+    tz_sign = (tz_secs < 0) and '-' or '+'
+    tz_defaultname = "%s%i%.2i" %(tz_sign, tz_hours, tz_mins)
+    tz_name = tzinfo.tzname(dt) or tz_defaultname
+    tz_fullname = getattr(tzinfo, 'zone', None) or tz_name
+
+    info = {('y', 2): unicode(dt.year)[2:],
+            ('y', 4): unicode(dt.year),
+            }
+
+    # Generic Numbers
+    for field, value in (('d', dt.day), ('D', int(dt.strftime('%j'))),
+                         ('F', day_of_week_in_month), ('k', dt.hour or 24),
+                         ('K', dt.hour%12), ('h', h), ('H', dt.hour),
+                         ('m', dt.minute), ('s', dt.second),
+                         ('S', dt.microsecond), ('w', int(dt.strftime('%W'))),
+                         ('W', week_in_month)):
+        for entry in _findFormattingCharacterInPattern(field, pattern):
+            info[entry] = (u'%%.%ii' %entry[1]) %value
+
+    # am/pm marker (Text)
+    for entry in _findFormattingCharacterInPattern('a', pattern):
+        info[entry] = ampm
+
+    # era designator (Text)
+    # TODO: works for gregorian only right now
+    for entry in _findFormattingCharacterInPattern('G', pattern):
+        info[entry] = calendar.eras[2][1]
+
+    # time zone (Text)
+    for entry in _findFormattingCharacterInPattern('z', pattern):
+        if entry[1] == 1:
+            info[entry] = u"%s%i%.2i" %(tz_sign, tz_hours, tz_mins)
+        elif entry[1] == 2:
+            info[entry] = u"%s%.2i:%.2i" %(tz_sign, tz_hours, tz_mins)
+        elif entry[1] == 3:
+            info[entry] = tz_name
+        else:
+            info[entry] = tz_fullname
+
+    # month in year (Text and Number)
+    for entry in _findFormattingCharacterInPattern('M', pattern):
+        if entry[1] == 1:
+            info[entry] = u'%i' %dt.month
+        elif entry[1] == 2:
+            info[entry] = u'%.2i' %dt.month
+        elif entry[1] == 3:
+            info[entry] = calendar.months[dt.month][1]
+        else:
+            info[entry] = calendar.months[dt.month][0]
+
+    # day in week (Text and Number)
+    for entry in _findFormattingCharacterInPattern('E', pattern):
+        if entry[1] == 1:
+            info[entry] = u'%i' %weekday
+        elif entry[1] == 2:
+            info[entry] = u'%.2i' %weekday
+        elif entry[1] == 3:
+            info[entry] = calendar.days[dt.weekday() + 1][1]
+        else:
+            info[entry] = calendar.days[dt.weekday() + 1][0]
+
+    return info
+
+
+# Number Pattern Parser States
+BEGIN = 0
+READ_PADDING_1 = 1
+READ_PREFIX = 2
+READ_PREFIX_STRING = 3
+READ_PADDING_2 = 4
+READ_INTEGER = 5
+READ_FRACTION = 6
+READ_EXPONENTIAL = 7
+READ_PADDING_3 = 8
+READ_SUFFIX = 9
+READ_SUFFIX_STRING = 10
+READ_PADDING_4 = 11
+READ_NEG_SUBPATTERN = 12
+
+# Binary Pattern Locators
+PADDING1 = 0
+PREFIX = 1
+PADDING2 = 2
+INTEGER = 3
+FRACTION = 4
+EXPONENTIAL = 5
+PADDING3 = 6
+SUFFIX = 7
+PADDING4 = 8
+GROUPING = 9
+
+class NumberPatternParseError(Exception):
+    """Number Pattern Parse Error"""
+
+
+def parseNumberPattern(pattern):
+    """Parses all sorts of number pattern."""
+    prefix = ''
+    padding_1 = None
+    padding_2 = None
+    padding_3 = None
+    padding_4 = None
+    integer = ''
+    fraction = ''
+    exponential = ''
+    suffix = ''
+    grouping = 0
+    neg_pattern = None
+
+    SPECIALCHARS = "*.,#0;E'"
+
+    length = len(pattern)
+    state = BEGIN
+    helper = ''
+    for pos in range(length):
+        char = pattern[pos]
+        if state == BEGIN:
+            if char == '*':
+                state = READ_PADDING_1
+            elif char not in SPECIALCHARS:
+                state = READ_PREFIX
+                prefix += char
+            elif char == "'":
+                state = READ_PREFIX_STRING
+            elif char in '#0':
+                state = READ_INTEGER
+                helper += char
+            else:
+                raise NumberPatternParseError(
+                      'Wrong syntax at beginning of pattern.')
+
+        elif state == READ_PADDING_1:
+            padding_1 = char
+            state = READ_PREFIX
+
+        elif state == READ_PREFIX:
+            if char == "*":
+                state = READ_PADDING_2
+            elif char == "'":
+                state = READ_PREFIX_STRING
+            elif char == "#" or char == "0":
+                state = READ_INTEGER
+                helper += char
+            else:
+                prefix += char
+
+        elif state == READ_PREFIX_STRING:
+            if char == "'":
+                state = READ_PREFIX
+            else:
+                prefix += char
+
+        elif state == READ_PADDING_2:
+            padding_2 = char
+            state = READ_INTEGER
+
+        elif state == READ_INTEGER:
+            if char == "#" or char == "0":
+                helper += char
+            elif char == ",":
+                grouping = 1
+            elif char == ".":
+                integer = helper
+                helper = ''
+                state = READ_FRACTION
+            elif char == "E":
+                integer = helper
+                helper = ''
+                state = READ_EXPONENTIAL
+            elif char == "*":
+                integer = helper
+                helper = ''
+                state = READ_PADDING_3
+            elif char == ";":
+                integer = helper
+                state = READ_NEG_SUBPATTERN
+            elif char == "'":
+                integer = helper
+                state = READ_SUFFIX_STRING
+            else:
+                integer = helper
+                suffix += char
+                state = READ_SUFFIX
+
+        elif state == READ_FRACTION:
+            if char == "#" or char == "0":
+                helper += char
+            elif char == "E":
+                fraction = helper
+                helper = ''
+                state = READ_EXPONENTIAL
+            elif char == "*":
+                fraction = helper
+                helper = ''
+                state = READ_PADDING_3
+            elif char == ";":
+                fraction = helper
+                state = READ_NEG_SUBPATTERN
+            elif char == "'":
+                fraction = helper
+                state = READ_SUFFIX_STRING
+            else:
+                fraction = helper
+                suffix += char
+                state = READ_SUFFIX
+
+        elif state == READ_EXPONENTIAL:
+            if char in ('0', '#', '+'):
+                helper += char
+            elif char == "*":
+                exponential = helper
+                helper = ''
+                state = READ_PADDING_3
+            elif char == ";":
+                exponential = helper
+                state = READ_NEG_SUBPATTERN
+            elif char == "'":
+                exponential = helper
+                state = READ_SUFFIX_STRING
+            else:
+                exponential = helper
+                suffix += char
+                state = READ_SUFFIX
+
+        elif state == READ_PADDING_3:
+            padding_3 = char
+            state = READ_SUFFIX
+
+        elif state == READ_SUFFIX:
+            if char == "*":
+                state = READ_PADDING_4
+            elif char == "'":
+                state = READ_SUFFIX_STRING
+            elif char == ";":
+                state = READ_NEG_SUBPATTERN
+            else:
+                suffix += char
+
+        elif state == READ_SUFFIX_STRING:
+            if char == "'":
+                state = READ_SUFFIX
+            else:
+                suffix += char
+
+        elif state == READ_PADDING_4:
+            if char == ';':
+                state = READ_NEG_SUBPATTERN
+            else:
+                padding_4 = char
+
+        elif state == READ_NEG_SUBPATTERN:
+            neg_pattern = parseNumberPattern(pattern[pos:])[0]
+            break
+
+    # Cleaning up states after end of parsing
+    if state == READ_INTEGER:
+        integer = helper
+    if state == READ_FRACTION:
+        fraction = helper
+    if state == READ_EXPONENTIAL:
+        exponential = helper
+
+    pattern = (padding_1, prefix, padding_2, integer, fraction, exponential,
+               padding_3, suffix, padding_4, grouping)
+
+    if neg_pattern is None:
+        neg_pattern = pattern
+
+    return pattern, neg_pattern