FA-40809 / Heap invariants / Member archive

Indexed erase invalidates the selected handle instead of the moved tail handle · case 04

The bounded indexed erase routing certificate reports an incorrect removed.

Member previewVariant 4 · 3 implementations · 7 checks per implementation

Case contract

An indexed heap erasure certificate gives slots [id,key], selected slot i, and a valid min-heap prefix before deletion. Fill the hole with the last record unless erasing the tail. Decide upward repair if replacement is smaller than its parent, otherwise downward; return shortened slots, removed id, direction, replacement handle location, retained identities, and logical size.

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	`{"direction": "up", "removed": "g", "replacement_location": ["g", 4], "retained": ["a", "b", "c", "d", "f", "g"], "size": 6, "slots": [["a", 1], ["b", 5], ["c", 2], ["d", 7], ["g", 4], ["f", 3]]}`	`{"direction": "up", "removed": "e", "replacement_location": ["g", 4], "retained": ["a", "b", "c", "d", "f", "g"], "size": 6, "slots": [["a", 1], ["b", 5], ["c", 2], ["d", 7], ["g", 4], ["f", 3]]}`	Failed

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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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