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Binomial extraction preserves rank collisions for later consolidation · case 02

The bounded binomial extract certificate reports an incorrect merge ranks.

Member previewVariant 2 · 3 implementations · 7 checks per implementation

Case contract

Extracted binomial root children are [id,rank,key] in descending rank. Remaining roots are [id,rank,key]. Return promoted root order, parent resets, cardinality delta, remaining minimum, merge rank sequence, and removed handle. Reversal restores ascending rank order before union.

Why this case matters

This isolates an internal heap representation or priority-structure invariant using deterministic finite records.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression certificate 3	`{"live_handles": [2, 3, 4, 7, 8], "merge_ranks": [0, 1, 2, 3], "minimum": 7, "parents": [[4, null], [3, null], [2, null]], "promoted": [2, 3, 4], "size_delta": -1}`	`{"live_handles": [2, 3, 4, 7, 8], "merge_ranks": [0, 0, 1, 2, 3], "minimum": 7, "parents": [[4, null], [3, null], [2, null]], "promoted": [2, 3, 4], "size_delta": -1}`	Failed

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