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  • Committer: Guilherme Salgado
  • Date: 2010-03-16 23:59:41 UTC
  • mto: This revision was merged to the branch mainline in revision 10537.
  • Revision ID: salgado@canonical.com-20100316235941-8uu1l14c1heo2ae5
Remove the lib/schoolbell/ package, lib/canonical/launchpad/components/cal.py and lib/canonical/launchpad/components/crowd.py

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lib/schoolbell/utils.py
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"""
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Utility functions for SchoolBell.
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These include various date manipulation routines.
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"""
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import calendar
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from datetime import datetime, date, timedelta, tzinfo
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def prev_month(date):
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    """Calculate the first day of the previous month for a given date.
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        >>> prev_month(date(2004, 8, 1))
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        datetime.date(2004, 7, 1)
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        >>> prev_month(date(2004, 8, 31))
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        datetime.date(2004, 7, 1)
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        >>> prev_month(date(2004, 12, 15))
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        datetime.date(2004, 11, 1)
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        >>> prev_month(date(2005, 1, 28))
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        datetime.date(2004, 12, 1)
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    """
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    return (date.replace(day=1) - timedelta(1)).replace(day=1)
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def next_month(date):
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    """Calculate the first day of the next month for a given date.
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        >>> next_month(date(2004, 8, 1))
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        datetime.date(2004, 9, 1)
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        >>> next_month(date(2004, 8, 31))
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        datetime.date(2004, 9, 1)
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        >>> next_month(date(2004, 12, 15))
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        datetime.date(2005, 1, 1)
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        >>> next_month(date(2004, 2, 28))
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        datetime.date(2004, 3, 1)
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        >>> next_month(date(2004, 2, 29))
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        datetime.date(2004, 3, 1)
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        >>> next_month(date(2005, 2, 28))
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        datetime.date(2005, 3, 1)
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    """
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    return (date.replace(day=28) + timedelta(7)).replace(day=1)
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def week_start(date, first_day_of_week=0):
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    """Calculate the first day of the week for a given date.
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    Assuming that week starts on Mondays:
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        >>> week_start(date(2004, 8, 19))
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        datetime.date(2004, 8, 16)
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        >>> week_start(date(2004, 8, 15))
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        datetime.date(2004, 8, 9)
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        >>> week_start(date(2004, 8, 14))
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        datetime.date(2004, 8, 9)
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        >>> week_start(date(2004, 8, 21))
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        datetime.date(2004, 8, 16)
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        >>> week_start(date(2004, 8, 22))
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        datetime.date(2004, 8, 16)
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        >>> week_start(date(2004, 8, 23))
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        datetime.date(2004, 8, 23)
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    Assuming that week starts on Sundays:
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        >>> import calendar
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        >>> week_start(date(2004, 8, 19), calendar.SUNDAY)
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        datetime.date(2004, 8, 15)
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        >>> week_start(date(2004, 8, 15), calendar.SUNDAY)
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        datetime.date(2004, 8, 15)
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        >>> week_start(date(2004, 8, 14), calendar.SUNDAY)
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        datetime.date(2004, 8, 8)
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        >>> week_start(date(2004, 8, 21), calendar.SUNDAY)
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        datetime.date(2004, 8, 15)
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        >>> week_start(date(2004, 8, 22), calendar.SUNDAY)
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        datetime.date(2004, 8, 22)
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        >>> week_start(date(2004, 8, 23), calendar.SUNDAY)
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        datetime.date(2004, 8, 22)
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    """
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    assert 0 <= first_day_of_week < 7
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    delta = date.weekday() - first_day_of_week
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    if delta < 0:
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        delta += 7
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    return date - timedelta(delta)
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def weeknum_bounds(year, weeknum):
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    """Calculate the inclusive date bounds for a (year, weeknum) tuple.
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    Week numbers are as defined in ISO 8601 and returned by
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    datetime.date.isocalendar().
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        >>> weeknum_bounds(2003, 52)
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        (datetime.date(2003, 12, 22), datetime.date(2003, 12, 28))
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        >>> weeknum_bounds(2004, 1)
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        (datetime.date(2003, 12, 29), datetime.date(2004, 1, 4))
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        >>> weeknum_bounds(2004, 2)
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        (datetime.date(2004, 1, 5), datetime.date(2004, 1, 11))
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    """
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    # The first week of a year is at least 4 days long, so January 4th
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    # is in the first week.
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    firstweek = week_start(date(year, 1, 4), calendar.MONDAY)
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    # move forward to the right week number
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    weekstart = firstweek + timedelta(weeks=weeknum-1)
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    weekend = weekstart + timedelta(days=6)
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    return (weekstart, weekend)
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def check_weeknum(year, weeknum):
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    """Check to see whether a (year, weeknum) tuple refers to a real
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    ISO week number.
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        >>> check_weeknum(2004, 1)
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        True
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        >>> check_weeknum(2004, 53)
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        True
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        >>> check_weeknum(2004, 0)
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        False
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        >>> check_weeknum(2004, 54)
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        False
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        >>> check_weeknum(2003, 52)
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        True
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        >>> check_weeknum(2003, 53)
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        False
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    """
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    weekstart, weekend = weeknum_bounds(year, weeknum)
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    isoyear, isoweek, isoday = weekstart.isocalendar()
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    return (year, weeknum) == (isoyear, isoweek)
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class Slots(dict):
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    """A dict with automatic key selection.
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    The add method automatically selects the lowest unused numeric key
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    (starting from 0).
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    Example:
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      >>> s = Slots()
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      >>> s.add("first")
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      >>> s
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      {0: 'first'}
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      >>> s.add("second")
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      >>> s
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      {0: 'first', 1: 'second'}
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    The keys can be reused:
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      >>> del s[0]
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      >>> s.add("third")
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      >>> s
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      {0: 'third', 1: 'second'}
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    """
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    def add(self, obj):
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        i = 0
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        while i in self:
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            i += 1
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        self[i] = obj