tz_convert sometimes returns results different from Pandas (but same as zoneinfo)

[shwina]

tz_convert returns a result different from Pandas for this pre-1900 example:

>>> pd.Series(["1899-01-01 12:00"], dtype="datetime64[s]").dt.tz_localize("Europe/Paris").dt.tz_convert("America/New_York")
0   1899-01-01 06:55:00-04:56
dtype: datetime64[ns, America/New_York]

>>> cudf.Series(["1899-01-01 12:00"], dtype="datetime64[s]").dt.tz_localize("Europe/Paris").dt.tz_convert("America/New_York")
0   1899-01-01 06:50:39-04:56
dtype: datetime64[s, America/New_York]

However, our result is the same as you would get with zoneinfo:

>>> datetime(1899, 1, 1, 12, 0, tzinfo=ZoneInfo("Europe/Paris")).astimezone(ZoneInfo("America/New_York"))
datetime.datetime(1899, 1, 1, 6, 50, 39, tzinfo=zoneinfo.ZoneInfo(key='America/New_York'))

@mroeschke I'm curious if this aligns with your experience with the difference between Pandas (pytz) and zoneinfo?

Originally posted by @shwina in #13328 (comment)

[mroeschke]

Yeah I've encountered pytz having different UTC offsets than other libraries in some of these edge cases.

FWIW pandas will default to zoneinfo in 3.0 so this will align with cudf in the future