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Cyclic priority cursor advance handles physical wrap and distinguishes no candidate · case 03

The bounded dial window certificate reports an incorrect advance.

Member previewVariant 3 · 3 implementations · 7 checks per implementation

Case contract

A cyclic integer bucket queue with ring size C stores entries [id,absolute_key]. Cursor is last extracted absolute key. Only keys in [cursor,cursor+C) are in the active window. Report physical bucket indices, expired ids, future-window ids, next active key, rotation distance, and active ids in absolute-key order. Same-slot values from later revolutions must not be delivered.

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 2	`{"active_order": ["a", "b"], "advance": -3, "buckets": [["a", 0], ["b", 1], ["c", 3]], "expired": [], "future": ["c"], "next": 4}`	`{"active_order": ["a", "b"], "advance": 1, "buckets": [["a", 0], ["b", 1], ["c", 3]], "expired": [], "future": ["c"], "next": 4}`	Failed

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