[andystaples]

Summary

• Add compatibility-aware modernization guidance: use current Python idioms without raising package minimum versions or changing public/runtime annotation behavior.
• Run Ruff's UP rules alongside Flake8 in the existing Nox lint session. Target Python 3.11 for core/Managed and Python 3.13 for Functions, including tests and examples; exclude generated protobuf files.
• Treat DeprecationWarning and PendingDeprecationWarning as errors in the root pytest configuration. Use Python 3.13 as the strict Nox deprecation gate while retaining the full compatibility matrices; other Nox interpreter versions continue to report these warnings without failing.
• Fix two small modernization findings, replace deprecated utcnow() calls in executor tests without changing naive-UTC timestamp comparisons, migrate the pagination test to the supported logger API, and assert warnings in tests deliberately exercising deprecated compatibility APIs.

Deliberate limits and follow-up

This does not attempt a repository-wide modernization sweep. Temporarily excluded rules do not reject new occurrences until their cleanup is complete:

• Typing-related rules are deferred pending runtime annotation and public compatibility review: Enable deferred Ruff typing modernization rules #322.
• UTC alias cleanup is deferred; the replacement is available in Python 3.11: Replace legacy UTC aliases and enable Ruff UP017 #323.
• Behavior-sensitive generator and enum suggestions have file-specific exceptions rather than repository-wide exclusions: Review behavior-sensitive Ruff UP028 and UP042 findings #324.
• Two upstream Functions loose-codec warnings remain visible but non-fatal, scoped by message, category, and module while legacy payload support is required: Review Functions loose-codec deprecation exceptions #325.

Ruff is not a comprehensive deprecated-API database, and runtime warning enforcement only covers executed code. Parent pytest filters do not govern separately launched Functions workers. Package versions and dependency minimums are unchanged.

[Copilot]

🟢 Approval recommended

The Python modernization and deprecation-check changes have no active review issues.

No open issues 🎉

What changed in this PR

Adds Python modernization and deprecation checks across the core SDK and both providers without changing package minimum versions or public API behavior.

Changes:

• Integrates Ruff modernization rules with Nox linting, using package-specific Python targets and scoped exclusions.
• Makes deprecation warnings fail tests by default, with Python 3.13 as the strict Nox gate while retaining compatibility coverage.
• Updates affected tests and documents guardrails and deferred cleanup.

File	Description
tests/​durabletask/​test_proto_task_hub_shim.py	Removes unnecessary class declaration parentheses.
tests/​durabletask/​test_orchestration_executor.py	Replaces deprecated UTC calls while preserving naive timestamps.
tests/​durabletask/​test_batch_actions.py	Uses the supported client logger parameter.
tests/​durabletask/​extensions/​history_export/​test_activities.py	Removes a redundant UTF-8 encoding argument.
tests/​durabletask-azuremanaged/​test_dts_batch_actions.py	Uses the supported Managed client logger parameter.
tests/​azure-functions-durable/​test_worker_compat.py	Asserts the expected retry-options deprecation warning.
tests/​azure-functions-durable/​test_client_compat.py	Asserts the expected entity unpickling deprecation warning.
pyproject.toml	Configures Ruff targets, exclusions, and pytest warning enforcement.
noxfile.py	Adds Ruff linting and interpreter-specific warning handling.
docs/​development.md	Explains checks, exceptions, and focused validation commands.
dev-requirements.txt	Adds Ruff as a development dependency.
.github/​copilot-instructions.md	Documents compatibility-aware modernization and warning-handling guidance.

_{Review effort: Balanced}