{"abstract":"Deque commit exposes slots the producer did not initialize.","category":"Bounded deques","checks":7,"contract":"A bounded deque write reservation publishes exactly its initialized prefix. Reject negative, uninitialized, over-reserved or over-capacity commit counts atomically. Successful commit releases the entire reservation and advances structure epoch only for nonempty publication.","evaluation_group":"s3-bounded-deques-write-reservation-commit","failed_approach":"The partial repair still applies the incorrect transition to an admitted boundary or multi-element case.","family":"s3-bounded-deques-write-reservation-commit-initialized-prefix","id":"FA-46921","implementations":{"attempt":{"sha256":"5802f979400c82f136fdb3d9030904a4dc3d41030f9173122c242299e9c67c1f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    a,reserved,values,written,cap,epoch=x\n    if written<0 or written>len(values) and not values or written>reserved:return [a,reserved,epoch,False,[]]\n    if len(a)+written>cap:return [a,reserved,epoch,False,[]]\n    published=values[:written]\n    state=a+published\n    remaining=0\n    version=epoch+(written>0)\n    unused=values[written:]\n    return [state,remaining,version,True,unused]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('0', solve([[N],3,[N+1,N+2,N+3],2,5,4]), {1: [[1, 2, 3], 0, 5, True, [4]], 2: [[2, 3, 4], 0, 5, True, [5]], 3: [[3, 4, 5], 0, 5, True, [6]], 4: [[4, 5, 6], 0, 5, True, [7]], 5: [[5, 6, 7], 0, 5, True, [8]]}[N])\ncheck('1', solve([[N],1,[N+1,N+2],2,4,2]), {1: [[1], 1, 2, False, []], 2: [[2], 1, 2, False, []], 3: [[3], 1, 2, False, []], 4: [[4], 1, 2, False, []], 5: [[5], 1, 2, False, []]}[N])\ncheck('2', solve([[N],3,[N+1],2,5,1]), {1: [[1], 3, 1, False, []], 2: [[2], 3, 1, False, []], 3: [[3], 3, 1, False, []], 4: [[4], 3, 1, False, []], 5: [[5], 3, 1, False, []]}[N])\ncheck('3', solve([[N,N+1],2,[N+2,N+3],2,3,5]), {1: [[1, 2], 2, 5, False, []], 2: [[2, 3], 2, 5, False, []], 3: [[3, 4], 2, 5, False, []], 4: [[4, 5], 2, 5, False, []], 5: [[5, 6], 2, 5, False, []]}[N])\ncheck('4', solve([[N],2,[N+1,N+2],0,4,7]), {1: [[1], 0, 7, True, [2, 3]], 2: [[2], 0, 7, True, [3, 4]], 3: [[3], 0, 7, True, [4, 5]], 4: [[4], 0, 7, True, [5, 6]], 5: [[5], 0, 7, True, [6, 7]]}[N])\ncheck('5', solve([[],2,[N,N+1],2,2,0]), {1: [[1, 2], 0, 1, True, []], 2: [[2, 3], 0, 1, True, []], 3: [[3, 4], 0, 1, True, []], 4: [[4, 5], 0, 1, True, []], 5: [[5, 6], 0, 1, True, []]}[N])\ncheck('6', solve([[N],2,[N+1],-1,4,1]), {1: [[1], 2, 1, False, []], 2: [[2], 2, 1, False, []], 3: [[3], 2, 1, False, []], 4: [[4], 2, 1, False, []], 5: [[5], 2, 1, False, []]}[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":"f2ff441436134597ea884c54cb0f04ee2a33728c6f331942f0e8be210a6d2cd2","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    a,reserved,values,written,cap,epoch=x\n    if written<0 or written>cap or written>reserved:return [a,reserved,epoch,False,[]]\n    if len(a)+written>cap:return [a,reserved,epoch,False,[]]\n    published=values[:written]\n    state=a+published\n    remaining=0\n    version=epoch+(written>0)\n    unused=values[written:]\n    return [state,remaining,version,True,unused]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('0', solve([[N],3,[N+1,N+2,N+3],2,5,4]), {1: [[1, 2, 3], 0, 5, True, [4]], 2: [[2, 3, 4], 0, 5, True, [5]], 3: [[3, 4, 5], 0, 5, True, [6]], 4: [[4, 5, 6], 0, 5, True, [7]], 5: [[5, 6, 7], 0, 5, True, [8]]}[N])\ncheck('1', solve([[N],1,[N+1,N+2],2,4,2]), {1: [[1], 1, 2, False, []], 2: [[2], 1, 2, False, []], 3: [[3], 1, 2, False, []], 4: [[4], 1, 2, False, []], 5: [[5], 1, 2, False, []]}[N])\ncheck('2', solve([[N],3,[N+1],2,5,1]), {1: [[1], 3, 1, False, []], 2: [[2], 3, 1, False, []], 3: [[3], 3, 1, False, []], 4: [[4], 3, 1, False, []], 5: [[5], 3, 1, False, []]}[N])\ncheck('3', solve([[N,N+1],2,[N+2,N+3],2,3,5]), {1: [[1, 2], 2, 5, False, []], 2: [[2, 3], 2, 5, False, []], 3: [[3, 4], 2, 5, False, []], 4: [[4, 5], 2, 5, False, []], 5: [[5, 6], 2, 5, False, []]}[N])\ncheck('4', solve([[N],2,[N+1,N+2],0,4,7]), {1: [[1], 0, 7, True, [2, 3]], 2: [[2], 0, 7, True, [3, 4]], 3: [[3], 0, 7, True, [4, 5]], 4: [[4], 0, 7, True, [5, 6]], 5: [[5], 0, 7, True, [6, 7]]}[N])\ncheck('5', solve([[],2,[N,N+1],2,2,0]), {1: [[1, 2], 0, 1, True, []], 2: [[2, 3], 0, 1, True, []], 3: [[3, 4], 0, 1, True, []], 4: [[4, 5], 0, 1, True, []], 5: [[5, 6], 0, 1, True, []]}[N])\ncheck('6', solve([[N],2,[N+1],-1,4,1]), {1: [[1], 2, 1, False, []], 2: [[2], 2, 1, False, []], 3: [[3], 2, 1, False, []], 4: [[4], 2, 1, False, []], 5: [[5], 2, 1, False, []]}[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"},"fixed":{"sha256":"d04c151eab77578e5fd2f097ecd2a06e0370c1f681d5a990ccd8e09c708c8668","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    a,reserved,values,written,cap,epoch=x\n    if written<0 or written>len(values) or written>reserved:return [a,reserved,epoch,False,[]]\n    if len(a)+written>cap:return [a,reserved,epoch,False,[]]\n    published=values[:written]\n    state=a+published\n    remaining=0\n    version=epoch+(written>0)\n    unused=values[written:]\n    return [state,remaining,version,True,unused]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('0', solve([[N],3,[N+1,N+2,N+3],2,5,4]), {1: [[1, 2, 3], 0, 5, True, [4]], 2: [[2, 3, 4], 0, 5, True, [5]], 3: [[3, 4, 5], 0, 5, True, [6]], 4: [[4, 5, 6], 0, 5, True, [7]], 5: [[5, 6, 7], 0, 5, True, [8]]}[N])\ncheck('1', solve([[N],1,[N+1,N+2],2,4,2]), {1: [[1], 1, 2, False, []], 2: [[2], 1, 2, False, []], 3: [[3], 1, 2, False, []], 4: [[4], 1, 2, False, []], 5: [[5], 1, 2, False, []]}[N])\ncheck('2', solve([[N],3,[N+1],2,5,1]), {1: [[1], 3, 1, False, []], 2: [[2], 3, 1, False, []], 3: [[3], 3, 1, False, []], 4: [[4], 3, 1, False, []], 5: [[5], 3, 1, False, []]}[N])\ncheck('3', solve([[N,N+1],2,[N+2,N+3],2,3,5]), {1: [[1, 2], 2, 5, False, []], 2: [[2, 3], 2, 5, False, []], 3: [[3, 4], 2, 5, False, []], 4: [[4, 5], 2, 5, False, []], 5: [[5, 6], 2, 5, False, []]}[N])\ncheck('4', solve([[N],2,[N+1,N+2],0,4,7]), {1: [[1], 0, 7, True, [2, 3]], 2: [[2], 0, 7, True, [3, 4]], 3: [[3], 0, 7, True, [4, 5]], 4: [[4], 0, 7, True, [5, 6]], 5: [[5], 0, 7, True, [6, 7]]}[N])\ncheck('5', solve([[],2,[N,N+1],2,2,0]), {1: [[1, 2], 0, 1, True, []], 2: [[2, 3], 0, 1, True, []], 3: [[3, 4], 0, 1, True, []], 4: [[4, 5], 0, 1, True, []], 5: [[5, 6], 0, 1, True, []]}[N])\ncheck('6', solve([[N],2,[N+1],-1,4,1]), {1: [[1], 2, 1, False, []], 2: [[2], 2, 1, False, []], 3: [[3], 2, 1, False, []], 4: [[4], 2, 1, False, []], 5: [[5], 2, 1, False, []]}[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-write-reservation-commit-initialized-prefix","generated_at":"2026-09-29T14:44:36.588469+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.","repair":"Restore the documented initialized prefix invariant in write-reservation-commit.","root_cause":"Deque commit exposes slots the producer did not initialize.","sha256":"389f7b953fbbb73bd6dd103ed272589694980530d95db8a10206d90b4b5fa787","title":"Deque commit exposes slots the producer did not initialize · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":39.612,"exit_code":1,"observations":[{"actual":[[1,2,3],0,5,true,[4]],"check":"0","expected":[[1,2,3],0,5,true,[4]],"passed":true},{"actual":[[1],1,2,false,[]],"check":"1","expected":[[1],1,2,false,[]],"passed":true},{"actual":[[1,2],0,2,true,[]],"check":"2","expected":[[1],3,1,false,[]],"passed":false},{"actual":[[1,2],2,5,false,[]],"check":"3","expected":[[1,2],2,5,false,[]],"passed":true},{"actual":[[1],0,7,true,[2,3]],"check":"4","expected":[[1],0,7,true,[2,3]],"passed":true},{"actual":[[1,2],0,1,true,[]],"check":"5","expected":[[1,2],0,1,true,[]],"passed":true},{"actual":[[1],2,1,false,[]],"check":"6","expected":[[1],2,1,false,[]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"0\", \"actual\": [[1, 2, 3], 0, 5, true, [4]], \"expected\": [[1, 2, 3], 0, 5, true, [4]], \"passed\": true}, {\"check\": \"1\", \"actual\": [[1], 1, 2, false, []], \"expected\": [[1], 1, 2, false, []], \"passed\": true}, {\"check\": \"2\", \"actual\": [[1, 2], 0, 2, true, []], \"expected\": [[1], 3, 1, false, []], \"passed\": false}, {\"check\": \"3\", \"actual\": [[1, 2], 2, 5, false, []], \"expected\": [[1, 2], 2, 5, false, []], \"passed\": true}, {\"check\": \"4\", \"actual\": [[1], 0, 7, true, [2, 3]], \"expected\": [[1], 0, 7, true, [2, 3]], \"passed\": true}, {\"check\": \"5\", \"actual\": [[1, 2], 0, 1, true, []], \"expected\": [[1, 2], 0, 1, true, []], \"passed\": true}, {\"check\": \"6\", \"actual\": [[1], 2, 1, false, []], \"expected\": [[1], 2, 1, false, []], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.798,"exit_code":1,"observations":[{"actual":[[1,2,3],0,5,true,[4]],"check":"0","expected":[[1,2,3],0,5,true,[4]],"passed":true},{"actual":[[1],1,2,false,[]],"check":"1","expected":[[1],1,2,false,[]],"passed":true},{"actual":[[1,2],0,2,true,[]],"check":"2","expected":[[1],3,1,false,[]],"passed":false},{"actual":[[1,2],2,5,false,[]],"check":"3","expected":[[1,2],2,5,false,[]],"passed":true},{"actual":[[1],0,7,true,[2,3]],"check":"4","expected":[[1],0,7,true,[2,3]],"passed":true},{"actual":[[1,2],0,1,true,[]],"check":"5","expected":[[1,2],0,1,true,[]],"passed":true},{"actual":[[1],2,1,false,[]],"check":"6","expected":[[1],2,1,false,[]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"0\", \"actual\": [[1, 2, 3], 0, 5, true, [4]], \"expected\": [[1, 2, 3], 0, 5, true, [4]], \"passed\": true}, {\"check\": \"1\", \"actual\": [[1], 1, 2, false, []], \"expected\": [[1], 1, 2, false, []], \"passed\": true}, {\"check\": \"2\", \"actual\": [[1, 2], 0, 2, true, []], \"expected\": [[1], 3, 1, false, []], \"passed\": false}, {\"check\": \"3\", \"actual\": [[1, 2], 2, 5, false, []], \"expected\": [[1, 2], 2, 5, false, []], \"passed\": true}, {\"check\": \"4\", \"actual\": [[1], 0, 7, true, [2, 3]], \"expected\": [[1], 0, 7, true, [2, 3]], \"passed\": true}, {\"check\": \"5\", \"actual\": [[1, 2], 0, 1, true, []], \"expected\": [[1, 2], 0, 1, true, []], \"passed\": true}, {\"check\": \"6\", \"actual\": [[1], 2, 1, false, []], \"expected\": [[1], 2, 1, false, []], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.745,"exit_code":0,"observations":[{"actual":[[1,2,3],0,5,true,[4]],"check":"0","expected":[[1,2,3],0,5,true,[4]],"passed":true},{"actual":[[1],1,2,false,[]],"check":"1","expected":[[1],1,2,false,[]],"passed":true},{"actual":[[1],3,1,false,[]],"check":"2","expected":[[1],3,1,false,[]],"passed":true},{"actual":[[1,2],2,5,false,[]],"check":"3","expected":[[1,2],2,5,false,[]],"passed":true},{"actual":[[1],0,7,true,[2,3]],"check":"4","expected":[[1],0,7,true,[2,3]],"passed":true},{"actual":[[1,2],0,1,true,[]],"check":"5","expected":[[1,2],0,1,true,[]],"passed":true},{"actual":[[1],2,1,false,[]],"check":"6","expected":[[1],2,1,false,[]],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"0\", \"actual\": [[1, 2, 3], 0, 5, true, [4]], \"expected\": [[1, 2, 3], 0, 5, true, [4]], \"passed\": true}, {\"check\": \"1\", \"actual\": [[1], 1, 2, false, []], \"expected\": [[1], 1, 2, false, []], \"passed\": true}, {\"check\": \"2\", \"actual\": [[1], 3, 1, false, []], \"expected\": [[1], 3, 1, false, []], \"passed\": true}, {\"check\": \"3\", \"actual\": [[1, 2], 2, 5, false, []], \"expected\": [[1, 2], 2, 5, false, []], \"passed\": true}, {\"check\": \"4\", \"actual\": [[1], 0, 7, true, [2, 3]], \"expected\": [[1], 0, 7, true, [2, 3]], \"passed\": true}, {\"check\": \"5\", \"actual\": [[1, 2], 0, 1, true, []], \"expected\": [[1, 2], 0, 1, true, []], \"passed\": true}, {\"check\": \"6\", \"actual\": [[1], 2, 1, false, []], \"expected\": [[1], 2, 1, false, []], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}