Fix reference leak when decoding msgpack Ext payloads - #1109
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Batches the changelog entries accumulated since the 0.21.1 release, following the usual pre-release batching practice (like msgspec#1020). Covers merged user-facing changes through msgspec#1109/msgspec#978/msgspec#1105; internal CI/benchmarking/test-infra changes are intentionally omitted. Also records the move to the msgspec GitHub organization. --------- Co-authored-by: Siyet <[email protected]>
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Fixes #1108.
Ext_Newdoesn't steal the reference todata(it does its ownPy_INCREF, matching the borrow contract expected by theExtconstructor). Both decode branches inmpack_decode_ext(typedExtdecode, andAnydecode without anext_hook) passed a fresh reference fromPyBytes_FromStringAndSizeand never released it, leaking one bytes object (the ext payload) per decoded Ext. Thedatetime(code -1) andext_hookbranches were not affected.The fix releases the caller's reference after constructing the
Ext, same pattern as theRaw.copy()leak fix (#709). Verified empirically: RSS delta over 200k decodes of a 1 KiB payload went from ~205 MiB to 0 on both affected branches; the new test fails before the fix (sys.getrefcount3 vs 2) and passes after.Thanks @K-ANOY for the precise report, the ownership analysis there was spot on.