Method construct_zone

Lib/test/test_zoneinfo/test_zoneinfo.py:858–974

(self, transitions, after=None, version=3)

            self.assertEqual(t.dst(), UTC.dst)

    def construct_zone(self, transitions, after=None, version=3):
        # These are not used for anything, so we're not going to include
        # them for now.
        isutc = []
        isstd = []
        leap_seconds = []

        offset_lists = [[], []]
        trans_times_lists = [[], []]
        trans_idx_lists = [[], []]

        v1_range = (-(2 ** 31), 2 ** 31)
        v2_range = (-(2 ** 63), 2 ** 63)
        ranges = [v1_range, v2_range]

        def zt_as_tuple(zt):
            # zt may be a tuple (timestamp, offset_before, offset_after) or
            # a ZoneTransition object — this is to allow the timestamp to be
            # values that are outside the valid range for datetimes but still
            # valid 64-bit timestamps.
            if isinstance(zt, tuple):
                return zt

            if zt.transition:
                trans_time = int(zt.transition_utc.timestamp())
            else:
                trans_time = None

            return (trans_time, zt.offset_before, zt.offset_after)

        transitions = sorted(map(zt_as_tuple, transitions), key=lambda x: x[0])

        for zt in transitions:
            trans_time, offset_before, offset_after = zt

            for v, (dt_min, dt_max) in enumerate(ranges):
                offsets = offset_lists[v]
                trans_times = trans_times_lists[v]
                trans_idx = trans_idx_lists[v]

                if trans_time is not None and not (
                    dt_min <= trans_time <= dt_max
                ):
                    continue

                if offset_before not in offsets:
                    offsets.append(offset_before)

                if offset_after not in offsets:
                    offsets.append(offset_after)

                if trans_time is not None:
                    trans_times.append(trans_time)
                    trans_idx.append(offsets.index(offset_after))

        isutcnt = len(isutc)
        isstdcnt = len(isstd)
        leapcnt = len(leap_seconds)