fix: preserve introspection metadata + coroutine-function detection (#43, #44)#81
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…#43, #44) #43: sync decorated functions returned the raw Rust object with no metadata — __name__/__qualname__/__module__/__doc__/__wrapped__ missing and inspect.signature collapsing to (*args, **kwargs), breaking logging, doc tools, and signature-introspecting frameworks (FastAPI, click). Only the async wrapper set these, so sync and async were inconsistent. Give CachedFunction and SharedCachedFunction a __dict__ (`#[pyclass(frozen, dict)]`) and apply functools.wraps(fn) to the returned object in the sync path. The Rust object is still returned directly, so __call__ stays a single FFI crossing (no Python wrapper on the hot path); the __dict__ is touched only at decoration time. inspect.signature now resolves via __wrapped__. #44: an async decorated function (AsyncCachedFunction instance with an `async def __call__`) was not detected by inspect/asyncio.iscoroutinefunction, so frameworks branching on it (FastAPI/Starlette, anyio, pytest-asyncio) treated it as sync and dropped the returned coroutine. Mark the wrapper in __init__: inspect.markcoroutinefunction on 3.12+, else the asyncio.coroutines._is_coroutine sentinel on 3.10/3.11. Tests (tests/test_introspection.py): sync (memory + shared) exposes name/qualname/module/doc/__wrapped__ and a resolvable signature and still caches; async keeps name/doc/signature and is detected as a coroutine function (verified across 3.10–3.13, covering both the markcoroutinefunction and sentinel paths). Verified fail-before -> pass-after. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The shared backend is Unix-only (lib.rs gates it behind not(windows); on Windows SharedCachedFunction is a stub whose __new__ rejects ttl). CI ignores the shared-backend test files on Windows, but the new test_introspection.py isn't in that ignore list, so test_sync_preserves_introspection[shared] ran on Windows and failed with "unexpected keyword argument 'ttl'". Mark the shared param skipif win32, matching the convention in the other shared tests. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Closes #43
Closes #44
Two related introspection bugs in the decorator, fixed together.
#43 — sync functions lose all introspection metadata
The sync path returned the raw Rust
CachedFunction/SharedCachedFunctiondirectly, which copied no metadata:__name__/__qualname__/__module__/__doc__/__wrapped__were missing andinspect.signature()collapsed to(*args, **kwargs). This breaks logging, documentation tools, and signature-introspecting frameworks (FastAPI, click) — and was inconsistent with the async wrapper, which already set these.Fix: give both pyclasses a
__dict__(#[pyclass(frozen, dict)]) and applyfunctools.wraps(fn)to the returned object in the sync path. The Rust object is still returned directly, so__call__stays a single FFI crossing (no Python wrapper on the hot path) — the__dict__is touched only at decoration time.inspect.signatureresolves through__wrapped__.#44 — async function not detected as a coroutine function
AsyncCachedFunctionis a plain class with anasync def __call__, but the instance wasn't flagged, soinspect.iscoroutinefunction/asyncio.iscoroutinefunctionreturnedFalsewhile calling it returned a coroutine. Frameworks branching oniscoroutinefunction(FastAPI/Starlette, anyio, pytest-asyncio) treated it as sync and dropped the returned coroutine ("coroutine was never awaited").Fix: mark the wrapper in
__init__—inspect.markcoroutinefunction(self)on Python 3.12+, else set theasyncio.coroutines._is_coroutinesentinel on 3.10/3.11 (the only pre-3.12 mechanismasyncio.iscoroutinefunctionrecognizes).Test —
tests/test_introspection.py__name__/__qualname__/__module__/__doc__/__wrapped__correct,inspect.signature==(a, b=2), and caching still works after wrapping.Verified fail-before → pass-after by stashing the fixes: the three targeted tests failed (missing metadata /
iscoroutinefunctionFalse); the async-introspection test already passed pre-fix (that path always set its dunders). The coroutine-detection test passes on 3.10–3.13, exercising both themarkcoroutinefunction(3.12+) and sentinel (3.10/3.11) paths.Gates run (risky — PyO3 boundary
#[pyclass]change; #44 is Python-version-dependent)make fmt/make lint(ruff, ty, clippy-D warnings) ✓make test—cargo test(11) + pytest (106, +4 new) ✓make test-matrix— Python 3.10–3.13 ✓ (3.14 skipped locally via the documenteduv-resolves-stale-alpha guard; CI covers 3.14 final)make bench— no regression: thedictflag doesn't touch__call__; memory ~18.2M ops/s, single-thread 17.5–21.8MNo public API surface change (same decorator/methods), so no README/docs updates.
🤖 Generated with Claude Code