fix(query): fix reference leak in captures_for_match - #471
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ObserverOfTime merged 1 commit intoJul 8, 2026
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nodes_for_capture_index() returns a new reference, and PyDict_SetItem() does not steal it -- it stores its own reference. The local nodes and captures references were never decref'd, leaking one node-list object per capture on every custom predicate evaluation. Fixes tree-sitter#467
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Fixes #467.
nodes_for_capture_index()returns a new reference, andPyDict_SetItem()doesn't steal it — it takes its own independent reference to the same object. The localnodesvariable (andcaptureson the error paths) was never released, so every capture evaluated through a custom query predicate leaked one node-list object permanently.Verified the leak and the fix by comparing
sys.getrefcount()on the captured list inside a custom predicate callback: 4 references before the fix, 3 after — matching the expected single-owner (the dict) refcount.