tests: fix unit test failure when auto_populated_fields is set

[parthea]

Fixes b/508597813

[gemini-code-assist]

Code Review

This pull request implements auto-population for the request_id field in CreateJob, CancelJob, and DeleteJob methods, as specified in the service configuration and verified in unit tests. Feedback indicates that the auto-population logic should be moved from the sample code into the generated RPC methods to fully comply with AIP-4235. Furthermore, the unit tests should be updated to use re.fullmatch for more robust UUID validation and to use empty strings instead of None when resetting proto3 string fields.

[gemini-code-assist]

According to AIP-4235, auto-population of fields should be handled by the client library's RPC methods. If the generator is updated to support auto_populated_fields, this logic should ideally be placed within the generated RPC methods rather than the sample code. This keeps the samples clean and ensures the feature is available to all users of the library, not just those following the samples.

References

1. According to AIP-4235, auto-population of fields should be handled by the client library's RPC methods. ^(link)

[gemini-code-assist]

There are two improvements that can be made here for better robustness and adherence to proto3 standards:

1. Use re.fullmatch instead of re.match to ensure the entire request_id string conforms to the UUID v4 format, preventing false positives from longer strings.
2. Set the field to an empty string "" instead of None. In proto3, string fields default to "". While proto-plus might handle None by converting it to the default, it is not valid for standard google.protobuf messages and can lead to TypeError or unexpected behavior in equality checks.

Suggested change

	assert re.match(r"[a-f0-9]{8}-?[a-f0-9]{4}-?4[a-f0-9]{3}-?[89ab][a-f0-9]{3}-?[a-f0-9]{12}", args[0].request_id)
	# clear UUID field so that the check below succeeds
	args[0].request_id = None
	assert re.fullmatch(r"[a-f0-9]{8}-?[a-f0-9]{4}-?4[a-f0-9]{3}-?[89ab][a-f0-9]{3}-?[a-f0-9]{12}", args[0].request_id)
	# clear UUID field so that the check below succeeds
	args[0].request_id = ""

References

1. In proto3, string fields default to an empty string (""). Using None is not valid for standard google.protobuf messages. ^(link)

[parthea]

The error in https://github.com/googleapis/google-cloud-python/actions/runs/25388575659/job/74456652962?pr=16944 matches what we have in b/508597813

                actual_params = req.call_args.kwargs['params']
>               assert expected_params == actual_params
E               AssertionError: assert [('jobId', '')] == [('requestId'...('jobId', '')]
E                 
E                 At index 0 diff: ('jobId', '') != ('requestId', 'a309a08f-90b8-42ec-a5cd-1490831692bd')
E                 Right contains one more item: ('jobId', '')
E                 Use -v to get more diff

tests/integration/storagebatchoperations_py_gapic_srcjar.py/tests/unit/gapic/storagebatchoperations_v1/test_storage_batch_operations.py:4136: AssertionError

[chalmerlowe]

NIT:

If this is generated by template, then all the match patterns should be identical. But it seems that the template could be better designed to have only one copy of the match pattern and have all match calls ref that pattern.

[parthea]

get_uuid4_re() is a macro in the template and is used in this PR. Can you share more details if this isn't what you meant?

google-cloud-python/packages/gapic-generator/gapic/templates/tests/unit/gapic/%name_%version/%sub/test_macros.j2

Lines 2198 to 2200 in ce71af0

	{% macro get_uuid4_re() -%}
	[a-f0-9]{8}-?[a-f0-9]{4}-?4[a-f0-9]{3}-?[89ab][a-f0-9]{3}-?[a-f0-9]{12}
	{%- endmacro %}{# uuid_re #}

main...repro-508597813#diff-a241fd9719e65e65cf1c9221d8c4704c7e5d7487f86b68d341d5055fde12d2a2R1231