`now('US/Pacific')` failing during DST transition

[tomage]

I've been evaluating a few libraries to use for my company, and as I have a testing "rig" that can run our unit-test suite under arbitrary datetimes of the year, I've especially been digging into daylight savings transitions.

There was a couple of oddities I did discover. One was #415, but the other one is this: Calling pendulum.now('US/Pacific') yielded different results than pendulum.now('UTC').in_tz('US/Pacific'), latter yielding correct results.

So, running this at 2019-11-03 08:30:00+00:00 (set by system time, or using libfreezetime or freezegun):

>>> now_utc_pt = pendulum.now('UTC').in_tz('US/Pacific')
>>> print(now_utc_pt.isoformat(), now_utc_pt.fold)
2019-11-03T01:30:00-07:00 0
>>> print(now_utc_pt.is_dst(), -now_utc_pt.utcoffset())
True 7:00:00
>>> now_pt = pendulum.now('US/Pacific')
>>> print(now_pt.isoformat(), now_pt.fold)
Conversely, let's ask directly for US/Pacific "now"
2019-11-03T01:30:00-08:00 1
>>> print(now_pt.is_dst(), -now_pt.utcoffset())
False 8:00:00

As with the other issue, I took the liberty to create a PR for a potential fix: #416.

Here's a small pyfiddle to showcase the behavior: https://pyfiddle.io/fiddle/f0ef4724-3af3-4e24-8a7c-254a17db9dec/?i=true

[tomage]

Fixed with #483 (comment).