Test Failure with "make integration-fail-fast" command

[peiwangdb]

Describe the bug

A clear and concise description of what the bug is. What command did you run? What happened?
I ran "make integration-fail-fast" command, it fails with

test/integration/004_simple_snapshot_test/test_simple_snapshot.py:862: in _snapshot_and_assert_invalidated
    self.assertGreaterEqual(result[-1].replace(tzinfo=pytz.UTC), self._invalidated_snapshot_datetime)
AssertionError: datetime.datetime(2021, 4, 26, 9, 7, 58, 180921, tzinfo=<UTC>) not greater than or equal to datetime.datetime(2021, 4, 26, 16, 7, 56, 828247, tzinfo=<UTC>)

Steps To Reproduce

run the command in the PST timezone.

Expected behavior

I don't understand why this fails.

Screenshots and log output

If applicable, add screenshots or log output to help explain your problem.

System information

Which database are you using dbt with?

• postgres
• redshift
• bigquery
• snowflake
• other (specify: ____________)

The output of dbt --version:
pulled from develop branch.

The operating system you're using:
MAC OS darwin

The output of python --version:
Python 3.8.8

Additional context

Add any other context about the problem here.

[jtcohen6]

@peiwangdb Thanks for raising this! I saw this happen intermittently before, but I wasn't sure of the cause. You gave the perfect clue:

run the command in the PST timezone.

I switched my computer to PST, and was able to reproduce this with ease. Nice!

I think the fix here is just a matter of switching .replace(tzinfo=pytz.UTC) with .astimezone(pytz.UTC) in the following spots. I switched those and was able to get this test passing locally, in PST + EST.
https://github.com/fishtown-analytics/dbt/blob/39f350fe89bd11215208be2513bb97020287a636/test/integration/004_simple_snapshot_test/test_simple_snapshot.py#L862
https://github.com/fishtown-analytics/dbt/blob/39f350fe89bd11215208be2513bb97020287a636/test/integration/004_simple_snapshot_test/test_simple_snapshot.py#L902
https://github.com/fishtown-analytics/dbt/blob/39f350fe89bd11215208be2513bb97020287a636/test/integration/004_simple_snapshot_test/test_simple_snapshot.py#L924

Is that a fix you'd be interesting in contributing? :)

[peiwangdb]

@jtcohen6 thanks a lot for the detailed guidance! I definitely would like to fix it!