DeepDiff Fails to Detect Timezone Changes in Arrays with ignore_order=True

[3schwartz]

Solution proposal for issue #516

Description

The deepdiff library is unable to detect timezone changes in datetimes within arrays.

When ignore_order=True and a datetime is present within an array, deepdiff uses an execution path that makes a DeepHash. Due to the implementation of datetime_normalize, all datetimes have their timezone set to UTC:

deepdiff/deepdiff/helper.py

Line 627 in c718369

obj = obj.replace(tzinfo=datetime.timezone.utc)

This behavior causes issues in our use case, as we rely on deepdiff to detect changes in datetime objects, including changes to their timezones.

Changes

Indent logic which replaces timezone to only affect those which has set truncate_datetime.

Notes

Existing logic was added in commits

• 9905016
• 7d39922

[seperman]

Hi @3schwartz
Thanks for making the PR! Looking at it now.

[seperman]

Hi @3schwartz
We currently treat timezone naive datetime objects as UTC datetimes. That is independent from truncate_datetime.
This also made me realize that we should convert the datetimes that have explicit timezone to their respective datetimes in UTC instead of "replacing" the timezone.
I have copy pasted your test and am playing with that idea. I will keep you posted.

[seperman]

@3schwartz Your PR made me realize we need to be more consistent with our timezone logic. I changed our logic to:

• Convert any datetime with timezone to the respective time in UTC
• Assume any timezone naive datetime to be in UTC

That has a conflict with what you wanted in your tests.
You can see the outcome of what I did here:
000ec0b