[HocVoNgThai]

The msgspec converter treats typed deques as passthrough sequences when their elements need no conversion. Msgspec cannot encode deques, so dumps() raises TypeError, including for deque fields inside attrs classes and dataclasses.

For example, a Queue dataclass with pending: deque[int] and value deque([1, 2]) currently fails to serialize. This change produces b'{"pending":[1,2]}', which loads back into the same queue.

Generate the normal iterable hook for deques, and resolve class field annotations before checking passthrough eligibility so postponed dataclass annotations work too. Add regressions for bare and typed deques, empty values, attrs/dataclass fields, dump hooks, and custom element hooks.

Closes #818

[codspeed]

Merging this PR will not alter performance

1 note

ℹ️ 64 benchmarks have no flamegraph

The flamegraph wasn't generated: the symbols of the profiling trace could not be resolved, because no information about the language frames was collected.

See affected benchmarks

✅ 64 untouched benchmarks

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_{Comparing HocVoNgThai:fix/msgspec-typed-deques (bd43263) with main (d043dbd)¹}

Footnotes

1. No successful run was found on main (8a23a31) during the generation of this report, so d043dbd was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Tinche]

LGTM. Please add a link to the PR and issue. Would be good to ensure all preconf converters can handle deques but that may be an issue for a different PR.

[Tinche]

Thanks!