[pickers] DateField behavior is impacted by the year format

[ash14]

[pickers] DateField behavior is impacted by the year format

[ash14]

It seems as if some internal logic is failing to zero out hour/minute components on time zone changes across dates (comparison with zero, perhaps?)

One way to reproduce this without "invalid" years like 200 can be, e.g. when in the Asia/Hong_Kong timezone:

• Paste 05/05/2020, output: 2020-05-04T16:00:00.000Z. Expected.
• Paste 25/12/1941, output: 1941-12-24T15:30:00.000Z. Expected.
• Paste back 05/05/2020 again, output is 2020-05-04T16:30:00.000Z which is not expected

[LukasTy]

This is a really strange behavior on dayjs side.
The problem seems to stem from the fact that the year 200 is considered valid by dayjs, but when a date is created, the offset gets messed up as seen in the screenshot below.
The first two lines are for the 2-digit year format
The 3rd and 4th lines are for the 4-digit year format
Both are in the America/New_York timezone on a device with GMT+3 timezone.

Pasting the 2005 value directly does not result in this problem.

This is just an initial report and needs further investigation.