{"abstract":"Block split leaves the boundary value in both blocks.","category":"Bounded deques","checks":6,"contract":"Split a deque storage block at an interior cut, keeping the original identity on the left and assigning a fresh right identity. Publish an incremented directory epoch and ordered block IDs without changing total element count.","contract_signature":"x","evaluation_group":"s3-bounded-deques-block-split","failed_approach":"The partial repair still applies the incorrect transition to an admitted boundary or multi-element case.","family":"s3-bounded-deques-block-split-left-extent","id":"FA-46361","implementations":{"attempt":{"sha256":"a2d1c3a83fed3b183d9c8280527c0b35d07a087f2315f83ef0957c7e7d2eba9a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    a,cut,old,fresh,epoch=x\n    left=a[:cut] if cut==1 else a[:cut+1]\n    right=a[cut:]\n    left_id=old\n    right_id=fresh\n    version=epoch+1\n    size=len(left)+len(right)\n    directory=[left_id,right_id]\n    return [left,right,left_id,right_id,version,size,directory]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('0', solve([[N,N+1,N+2,N+3],2,8,9,3]), {1: [[1, 2], [3, 4], 8, 9, 4, 4, [8, 9]], 2: [[2, 3], [4, 5], 8, 9, 4, 4, [8, 9]], 3: [[3, 4], [5, 6], 8, 9, 4, 4, [8, 9]], 4: [[4, 5], [6, 7], 8, 9, 4, 4, [8, 9]], 5: [[5, 6], [7, 8], 8, 9, 4, 4, [8, 9]]}[N])\ncheck('1', solve([[N,N+1,N+2],1,2,4,0]), {1: [[1], [2, 3], 2, 4, 1, 3, [2, 4]], 2: [[2], [3, 4], 2, 4, 1, 3, [2, 4]], 3: [[3], [4, 5], 2, 4, 1, 3, [2, 4]], 4: [[4], [5, 6], 2, 4, 1, 3, [2, 4]], 5: [[5], [6, 7], 2, 4, 1, 3, [2, 4]]}[N])\ncheck('2', solve([[N,N+1],1,7,11,5]), {1: [[1], [2], 7, 11, 6, 2, [7, 11]], 2: [[2], [3], 7, 11, 6, 2, [7, 11]], 3: [[3], [4], 7, 11, 6, 2, [7, 11]], 4: [[4], [5], 7, 11, 6, 2, [7, 11]], 5: [[5], [6], 7, 11, 6, 2, [7, 11]]}[N])\ncheck('3', solve([[N,N+1,N+2,N+3,N+4],3,12,13,4]), {1: [[1, 2, 3], [4, 5], 12, 13, 5, 5, [12, 13]], 2: [[2, 3, 4], [5, 6], 12, 13, 5, 5, [12, 13]], 3: [[3, 4, 5], [6, 7], 12, 13, 5, 5, [12, 13]], 4: [[4, 5, 6], [7, 8], 12, 13, 5, 5, [12, 13]], 5: [[5, 6, 7], [8, 9], 12, 13, 5, 5, [12, 13]]}[N])\ncheck('4', solve([[N,N+1,N+2,N+3],1,3,8,2]), {1: [[1], [2, 3, 4], 3, 8, 3, 4, [3, 8]], 2: [[2], [3, 4, 5], 3, 8, 3, 4, [3, 8]], 3: [[3], [4, 5, 6], 3, 8, 3, 4, [3, 8]], 4: [[4], [5, 6, 7], 3, 8, 3, 4, [3, 8]], 5: [[5], [6, 7, 8], 3, 8, 3, 4, [3, 8]]}[N])\ncheck('5', solve([[N,N+1,N+2,N+3,N+4],4,5,6,8]), {1: [[1, 2, 3, 4], [5], 5, 6, 9, 5, [5, 6]], 2: [[2, 3, 4, 5], [6], 5, 6, 9, 5, [5, 6]], 3: [[3, 4, 5, 6], [7], 5, 6, 9, 5, [5, 6]], 4: [[4, 5, 6, 7], [8], 5, 6, 9, 5, [5, 6]], 5: [[5, 6, 7, 8], [9], 5, 6, 9, 5, [5, 6]]}[N])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"adb378e36822eea370518a2283b6862d445615cb6e561b5e53ca25b23af5a9b0","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    a,cut,old,fresh,epoch=x\n    left=a[:cut+1]\n    right=a[cut:]\n    left_id=old\n    right_id=fresh\n    version=epoch+1\n    size=len(left)+len(right)\n    directory=[left_id,right_id]\n    return [left,right,left_id,right_id,version,size,directory]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('0', solve([[N,N+1,N+2,N+3],2,8,9,3]), {1: [[1, 2], [3, 4], 8, 9, 4, 4, [8, 9]], 2: [[2, 3], [4, 5], 8, 9, 4, 4, [8, 9]], 3: [[3, 4], [5, 6], 8, 9, 4, 4, [8, 9]], 4: [[4, 5], [6, 7], 8, 9, 4, 4, [8, 9]], 5: [[5, 6], [7, 8], 8, 9, 4, 4, [8, 9]]}[N])\ncheck('1', solve([[N,N+1,N+2],1,2,4,0]), {1: [[1], [2, 3], 2, 4, 1, 3, [2, 4]], 2: [[2], [3, 4], 2, 4, 1, 3, [2, 4]], 3: [[3], [4, 5], 2, 4, 1, 3, [2, 4]], 4: [[4], [5, 6], 2, 4, 1, 3, [2, 4]], 5: [[5], [6, 7], 2, 4, 1, 3, [2, 4]]}[N])\ncheck('2', solve([[N,N+1],1,7,11,5]), {1: [[1], [2], 7, 11, 6, 2, [7, 11]], 2: [[2], [3], 7, 11, 6, 2, [7, 11]], 3: [[3], [4], 7, 11, 6, 2, [7, 11]], 4: [[4], [5], 7, 11, 6, 2, [7, 11]], 5: [[5], [6], 7, 11, 6, 2, [7, 11]]}[N])\ncheck('3', solve([[N,N+1,N+2,N+3,N+4],3,12,13,4]), {1: [[1, 2, 3], [4, 5], 12, 13, 5, 5, [12, 13]], 2: [[2, 3, 4], [5, 6], 12, 13, 5, 5, [12, 13]], 3: [[3, 4, 5], [6, 7], 12, 13, 5, 5, [12, 13]], 4: [[4, 5, 6], [7, 8], 12, 13, 5, 5, [12, 13]], 5: [[5, 6, 7], [8, 9], 12, 13, 5, 5, [12, 13]]}[N])\ncheck('4', solve([[N,N+1,N+2,N+3],1,3,8,2]), {1: [[1], [2, 3, 4], 3, 8, 3, 4, [3, 8]], 2: [[2], [3, 4, 5], 3, 8, 3, 4, [3, 8]], 3: [[3], [4, 5, 6], 3, 8, 3, 4, [3, 8]], 4: [[4], [5, 6, 7], 3, 8, 3, 4, [3, 8]], 5: [[5], [6, 7, 8], 3, 8, 3, 4, [3, 8]]}[N])\ncheck('5', solve([[N,N+1,N+2,N+3,N+4],4,5,6,8]), {1: [[1, 2, 3, 4], [5], 5, 6, 9, 5, [5, 6]], 2: [[2, 3, 4, 5], [6], 5, 6, 9, 5, [5, 6]], 3: [[3, 4, 5, 6], [7], 5, 6, 9, 5, [5, 6]], 4: [[4, 5, 6, 7], [8], 5, 6, 9, 5, [5, 6]], 5: [[5, 6, 7, 8], [9], 5, 6, 9, 5, [5, 6]]}[N])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Offline finite deterministic model; no claim of production implementation or concurrent memory-model conformance. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"s3-bounded-deques-block-split-left-extent","generated_at":"2026-09-29T14:44:31.608993+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Controlled bounded deque implementation model with explicit storage and lifecycle observations.","root_cause":"Block split leaves the boundary value in both blocks.","sha256":"41be0e68bf2a9d895c7da396f2e0383b54a919c2db69ffd00482b6f2cb23d447","title":"Block split leaves the boundary value in both blocks · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":40.729,"exit_code":1,"observations":[{"actual":[[1,2,3],[3,4],8,9,4,5,[8,9]],"check":"0","expected":[[1,2],[3,4],8,9,4,4,[8,9]],"passed":false},{"actual":[[1],[2,3],2,4,1,3,[2,4]],"check":"1","expected":[[1],[2,3],2,4,1,3,[2,4]],"passed":true},{"actual":[[1],[2],7,11,6,2,[7,11]],"check":"2","expected":[[1],[2],7,11,6,2,[7,11]],"passed":true},{"actual":[[1,2,3,4],[4,5],12,13,5,6,[12,13]],"check":"3","expected":[[1,2,3],[4,5],12,13,5,5,[12,13]],"passed":false},{"actual":[[1],[2,3,4],3,8,3,4,[3,8]],"check":"4","expected":[[1],[2,3,4],3,8,3,4,[3,8]],"passed":true},{"actual":[[1,2,3,4,5],[5],5,6,9,6,[5,6]],"check":"5","expected":[[1,2,3,4],[5],5,6,9,5,[5,6]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"0\", \"actual\": [[1, 2, 3], [3, 4], 8, 9, 4, 5, [8, 9]], \"expected\": [[1, 2], [3, 4], 8, 9, 4, 4, [8, 9]], \"passed\": false}, {\"check\": \"1\", \"actual\": [[1], [2, 3], 2, 4, 1, 3, [2, 4]], \"expected\": [[1], [2, 3], 2, 4, 1, 3, [2, 4]], \"passed\": true}, {\"check\": \"2\", \"actual\": [[1], [2], 7, 11, 6, 2, [7, 11]], \"expected\": [[1], [2], 7, 11, 6, 2, [7, 11]], \"passed\": true}, {\"check\": \"3\", \"actual\": [[1, 2, 3, 4], [4, 5], 12, 13, 5, 6, [12, 13]], \"expected\": [[1, 2, 3], [4, 5], 12, 13, 5, 5, [12, 13]], \"passed\": false}, {\"check\": \"4\", \"actual\": [[1], [2, 3, 4], 3, 8, 3, 4, [3, 8]], \"expected\": [[1], [2, 3, 4], 3, 8, 3, 4, [3, 8]], \"passed\": true}, {\"check\": \"5\", \"actual\": [[1, 2, 3, 4, 5], [5], 5, 6, 9, 6, [5, 6]], \"expected\": [[1, 2, 3, 4], [5], 5, 6, 9, 5, [5, 6]], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.104,"exit_code":1,"observations":[{"actual":[[1,2,3],[3,4],8,9,4,5,[8,9]],"check":"0","expected":[[1,2],[3,4],8,9,4,4,[8,9]],"passed":false},{"actual":[[1,2],[2,3],2,4,1,4,[2,4]],"check":"1","expected":[[1],[2,3],2,4,1,3,[2,4]],"passed":false},{"actual":[[1,2],[2],7,11,6,3,[7,11]],"check":"2","expected":[[1],[2],7,11,6,2,[7,11]],"passed":false},{"actual":[[1,2,3,4],[4,5],12,13,5,6,[12,13]],"check":"3","expected":[[1,2,3],[4,5],12,13,5,5,[12,13]],"passed":false},{"actual":[[1,2],[2,3,4],3,8,3,5,[3,8]],"check":"4","expected":[[1],[2,3,4],3,8,3,4,[3,8]],"passed":false},{"actual":[[1,2,3,4,5],[5],5,6,9,6,[5,6]],"check":"5","expected":[[1,2,3,4],[5],5,6,9,5,[5,6]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"0\", \"actual\": [[1, 2, 3], [3, 4], 8, 9, 4, 5, [8, 9]], \"expected\": [[1, 2], [3, 4], 8, 9, 4, 4, [8, 9]], \"passed\": false}, {\"check\": \"1\", \"actual\": [[1, 2], [2, 3], 2, 4, 1, 4, [2, 4]], \"expected\": [[1], [2, 3], 2, 4, 1, 3, [2, 4]], \"passed\": false}, {\"check\": \"2\", \"actual\": [[1, 2], [2], 7, 11, 6, 3, [7, 11]], \"expected\": [[1], [2], 7, 11, 6, 2, [7, 11]], \"passed\": false}, {\"check\": \"3\", \"actual\": [[1, 2, 3, 4], [4, 5], 12, 13, 5, 6, [12, 13]], \"expected\": [[1, 2, 3], [4, 5], 12, 13, 5, 5, [12, 13]], \"passed\": false}, {\"check\": \"4\", \"actual\": [[1, 2], [2, 3, 4], 3, 8, 3, 5, [3, 8]], \"expected\": [[1], [2, 3, 4], 3, 8, 3, 4, [3, 8]], \"passed\": false}, {\"check\": \"5\", \"actual\": [[1, 2, 3, 4, 5], [5], 5, 6, 9, 6, [5, 6]], \"expected\": [[1, 2, 3, 4], [5], 5, 6, 9, 5, [5, 6]], \"passed\": false}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}