utils.py 文件源码

def occurrences_after(self, after=None, tzinfo=pytz.utc):
        """
        It is often useful to know what the next occurrence is given a list of
        events.  This function produces a generator that yields the
        the most recent occurrence after the date ``after`` from any of the
        events in ``self.events``
        """
        from schedule.models import Occurrence

        if after is None:
            after = timezone.now()
        occ_replacer = OccurrenceReplacer(
            Occurrence.objects.filter(event__in=self.events))
        generators = [event._occurrences_after_generator(after) for event in self.events]
        occurrences = []

        for generator in generators:
            try:
                heapq.heappush(occurrences, (next(generator), generator))
            except StopIteration:
                pass

        while True:
            if len(occurrences) == 0:
                raise StopIteration

            generator = occurrences[0][1]

            try:
                next_occurence = heapq.heapreplace(occurrences, (next(generator), generator))[0]
            except StopIteration:
                next_occurence = heapq.heappop(occurrences)[0]
            yield occ_replacer.get_occurrence(next_occurence)