jpayne@69: '''
jpayne@69: Custom exceptions raised by pytz.
jpayne@69: '''
jpayne@69: 
jpayne@69: __all__ = [
jpayne@69:     'UnknownTimeZoneError', 'InvalidTimeError', 'AmbiguousTimeError',
jpayne@69:     'NonExistentTimeError',
jpayne@69: ]
jpayne@69: 
jpayne@69: 
jpayne@69: class Error(Exception):
jpayne@69:     '''Base class for all exceptions raised by the pytz library'''
jpayne@69: 
jpayne@69: 
jpayne@69: class UnknownTimeZoneError(KeyError, Error):
jpayne@69:     '''Exception raised when pytz is passed an unknown timezone.
jpayne@69: 
jpayne@69:     >>> isinstance(UnknownTimeZoneError(), LookupError)
jpayne@69:     True
jpayne@69: 
jpayne@69:     This class is actually a subclass of KeyError to provide backwards
jpayne@69:     compatibility with code relying on the undocumented behavior of earlier
jpayne@69:     pytz releases.
jpayne@69: 
jpayne@69:     >>> isinstance(UnknownTimeZoneError(), KeyError)
jpayne@69:     True
jpayne@69: 
jpayne@69:     And also a subclass of pytz.exceptions.Error, as are other pytz
jpayne@69:     exceptions.
jpayne@69: 
jpayne@69:     >>> isinstance(UnknownTimeZoneError(), Error)
jpayne@69:     True
jpayne@69: 
jpayne@69:     '''
jpayne@69:     pass
jpayne@69: 
jpayne@69: 
jpayne@69: class InvalidTimeError(Error):
jpayne@69:     '''Base class for invalid time exceptions.'''
jpayne@69: 
jpayne@69: 
jpayne@69: class AmbiguousTimeError(InvalidTimeError):
jpayne@69:     '''Exception raised when attempting to create an ambiguous wallclock time.
jpayne@69: 
jpayne@69:     At the end of a DST transition period, a particular wallclock time will
jpayne@69:     occur twice (once before the clocks are set back, once after). Both
jpayne@69:     possibilities may be correct, unless further information is supplied.
jpayne@69: 
jpayne@69:     See DstTzInfo.normalize() for more info
jpayne@69:     '''
jpayne@69: 
jpayne@69: 
jpayne@69: class NonExistentTimeError(InvalidTimeError):
jpayne@69:     '''Exception raised when attempting to create a wallclock time that
jpayne@69:     cannot exist.
jpayne@69: 
jpayne@69:     At the start of a DST transition period, the wallclock time jumps forward.
jpayne@69:     The instants jumped over never occur.
jpayne@69:     '''