test: add utils acceptance scenarios

[marandaneto]

💡 Motivation and Context

follow up #577

Add pytest-bdd acceptance coverage for posthog/utils.py on top of the CRAP-score work. These scenarios document end-to-end utility behavior in Gherkin while still running through the existing pytest CI job.

💚 How did you test it?

• uv run --extra test pytest posthog/test/test_utils_acceptance.py --timeout=30 -q
• uv run --extra test pytest --timeout=30 -q
• uvx ruff check posthog/test/test_utils_acceptance.py pyproject.toml

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

If releasing new changes

• Ran sampo add to generate a changeset file

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	pytest-bdd@​8.1.0

View full report

[github-actions]

posthog-python Compliance Report

Date: 2026-05-16 01:14:13 UTC
Duration: 4673918ms

⚠️ Some Tests Failed

29/45 tests passed, 16 failed

---

Capture Tests

✅ 29/29 tests passed

View Details

Test	Status	Duration
Format Validation.Event Has Required Fields	✅	515ms
Format Validation.Event Has Uuid	✅	1507ms
Format Validation.Event Has Lib Properties	✅	1506ms
Format Validation.Distinct Id Is String	✅	1506ms
Format Validation.Token Is Present	✅	1507ms
Format Validation.Custom Properties Preserved	✅	1506ms
Format Validation.Event Has Timestamp	✅	1507ms
Retry Behavior.Retries On 503	✅	9517ms
Retry Behavior.Does Not Retry On 400	✅	3504ms
Retry Behavior.Does Not Retry On 401	✅	3509ms
Retry Behavior.Respects Retry After Header	✅	9510ms
Retry Behavior.Implements Backoff	✅	23517ms
Retry Behavior.Retries On 500	✅	7018ms
Retry Behavior.Retries On 502	✅	7512ms
Retry Behavior.Retries On 504	✅	7512ms
Retry Behavior.Max Retries Respected	✅	23526ms
Deduplication.Generates Unique Uuids	✅	1499ms
Deduplication.Preserves Uuid On Retry	✅	7515ms
Deduplication.Preserves Uuid And Timestamp On Retry	✅	14512ms
Deduplication.Preserves Uuid And Timestamp On Batch Retry	✅	7516ms
Deduplication.No Duplicate Events In Batch	✅	1503ms
Deduplication.Different Events Have Different Uuids	✅	1507ms
Compression.Sends Gzip When Enabled	✅	1506ms
Batch Format.Uses Proper Batch Structure	✅	1506ms
Batch Format.Flush With No Events Sends Nothing	✅	1005ms
Batch Format.Multiple Events Batched Together	✅	1505ms
Error Handling.Does Not Retry On 403	✅	3509ms
Error Handling.Does Not Retry On 413	✅	3507ms
Error Handling.Retries On 408	✅	7512ms

Feature_Flags Tests

⚠️ 0/16 tests passed, 16 failed

View Details

Test	Status	Duration
Request Payload.Request With Person Properties Device Id	❌	506ms
Request Payload.Flags Request Uses V2 Query Param	❌	300400ms
Request Payload.Flags Request Hits Flags Path Not Decide	❌	300944ms
Request Payload.Flags Request Omits Authorization Header	❌	301022ms
Request Payload.Token In Flags Body Matches Init	❌	301010ms
Request Payload.Groups Round Trip	❌	300987ms
Request Payload.Groups Default To Empty Object	❌	300997ms
Request Payload.Person Properties Distinct Id Auto Populated When Caller Omits It	❌	301069ms
Request Payload.Disable Geoip False Propagates As Geoip Disable False	❌	300961ms
Request Payload.Disable Geoip Omitted Defaults To False	❌	301030ms
Request Payload.Flag Keys To Evaluate Contains Only Requested Key	❌	301014ms
Request Lifecycle.No Flags Request On Init Alone	❌	300951ms
Request Lifecycle.No Flags Request On Normal Capture	❌	301052ms
Request Lifecycle.Two Flag Calls Produce Two Remote Requests	❌	300963ms
Request Lifecycle.Mock Response Value Is Returned To Caller	❌	301002ms
Side Effect Events.Get Feature Flag Captures Feature Flag Called Event	❌	301014ms

Failures

request_payload.request_with_person_properties_device_id

Field 'token' not found in /flags request body at path 'token'. Available keys: ['distinct_id', 'groups', 'person_properties', 'group_properties', 'geoip_disable', 'device_id', 'flag_keys_to_evaluate', 'sentAt', 'api_key']

request_payload.flags_request_uses_v2_query_param

No error message

request_payload.flags_request_hits_flags_path_not_decide

No error message

request_payload.flags_request_omits_authorization_header

No error message

request_payload.token_in_flags_body_matches_init

No error message

request_payload.groups_round_trip

No error message

request_payload.groups_default_to_empty_object

No error message

request_payload.person_properties_distinct_id_auto_populated_when_caller_omits_it

No error message

request_payload.disable_geoip_false_propagates_as_geoip_disable_false

No error message

request_payload.disable_geoip_omitted_defaults_to_false

No error message

request_payload.flag_keys_to_evaluate_contains_only_requested_key

No error message

request_lifecycle.no_flags_request_on_init_alone

No error message

request_lifecycle.no_flags_request_on_normal_capture

No error message

request_lifecycle.two_flag_calls_produce_two_remote_requests

No error message

request_lifecycle.mock_response_value_is_returned_to_caller

No error message

side_effect_events.get_feature_flag_captures_feature_flag_called_event

No error message