[HuaTNA]

A registered callback can be callable while having a false truth value, such as an empty list that records requests in __call__. Both request handlers currently mark it as matched but skip calling it, raising a misleading timeout.

Check callback is not None in synchronous and asynchronous dispatch. Add regressions through real HTTPX clients and the public fixture, plus the required changelog entry.

Fixes #256.

Validation on macOS arm64 / CPython 3.13.13, HTTPX 0.28.1 and pytest 9.1.1:

• Both regression cases fail on the baseline and pass with the fix.
• Full suite: 356 passed, 100% statement and branch coverage, meeting the configured threshold.
• All pinned pre-commit hooks pass, including Black, Flake8, Mypy and Ruff; dependency consistency checks pass.
• Source distribution and wheel builds pass; the wheel contains the exact tested _httpx_mock.py.
• Separate local controls confirm false-valued async callable objects are awaited/reused and invalid callback results still produce the required response-validation error.

Other Python versions and OS matrices were not run locally. No external server was contacted.

Discovery and AI disclosure: found during callback-dispatch code analysis and reproduced through the public API. An autonomous Codex assistant prepared and tested this contribution under the submitting account's authorization; it has not received independent human review.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud