{"abstract":"A queue exceeds capacity or silently drops a suffix after accepting a batch.","category":"Runtime and resources","checks":7,"contract":"Capacity is nonnegative and the initial queue fits. Return [new queue,accepted]. A batch is atomic: all items append in order or none do. An empty batch succeeds even at zero capacity. The check and append are one serialized state transition in this model.","evaluation_group":"model-15c5ca28bde05d22","failed_approach":"Truncating the resulting queue enforces a size bound but violates all-or-nothing admission.","family":"runtime-atomic-batch-admission","id":"FA-231","implementations":{"attempt":{"sha256":"8aacaf2519b78db462dc45f7b0c038c97404be88ff0cacb3401df75fd67d1fbb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(capacity, queue, batch):\n    return [(list(queue)+list(batch))[:capacity], len(queue) < capacity]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nqueue = list(range(N))\ncheck('oversize batch is rejected intact', solve(N+1, queue, ['a', 'b']), [queue, False])\ncheck('exact fit admitted', solve(N+2, queue, ['a', 'b']), [queue+['a', 'b'], True])\ncheck('empty batch on full queue', solve(N, queue, []), [queue, True])\ncheck('zero capacity empty batch', solve(0, [], []), [[], True])\ncheck('zero capacity nonempty batch', solve(0, [], [N]), [[], False])\ncheck('oversize from empty', solve(N, [], list(range(N+1))), [[], False])\ncheck('room for small batch', solve(3*N, queue, [N]), [queue+[N], True])\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":"db9dcd1f8250c598cbc3620002ca710e050422c1fa0338874b7cfdf639fb0530","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(capacity, queue, batch):\n    allowed = len(queue) < capacity\n    return [list(queue)+list(batch), True] if allowed else [list(queue), False]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nqueue = list(range(N))\ncheck('oversize batch is rejected intact', solve(N+1, queue, ['a', 'b']), [queue, False])\ncheck('exact fit admitted', solve(N+2, queue, ['a', 'b']), [queue+['a', 'b'], True])\ncheck('empty batch on full queue', solve(N, queue, []), [queue, True])\ncheck('zero capacity empty batch', solve(0, [], []), [[], True])\ncheck('zero capacity nonempty batch', solve(0, [], [N]), [[], False])\ncheck('oversize from empty', solve(N, [], list(range(N+1))), [[], False])\ncheck('room for small batch', solve(3*N, queue, [N]), [queue+[N], True])\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":"4d00dc0b66bb0bfce854cf6097284955f5a8b2c5e4bf4d00230992e32c229a9b","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(capacity, queue, batch):\n    allowed = len(queue)+len(batch) <= capacity\n    return [list(queue)+list(batch), True] if allowed else [list(queue), False]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nqueue = list(range(N))\ncheck('oversize batch is rejected intact', solve(N+1, queue, ['a', 'b']), [queue, False])\ncheck('exact fit admitted', solve(N+2, queue, ['a', 'b']), [queue+['a', 'b'], True])\ncheck('empty batch on full queue', solve(N, queue, []), [queue, True])\ncheck('zero capacity empty batch', solve(0, [], []), [[], True])\ncheck('zero capacity nonempty batch', solve(0, [], [N]), [[], False])\ncheck('oversize from empty', solve(N, [], list(range(N+1))), [[], False])\ncheck('room for small batch', solve(3*N, queue, [N]), [queue+[N], True])\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":" 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":"runtime-atomic-batch-admission","generated_at":"2026-09-29T14:36:51.526279+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Models bounded work admission for a logically indivisible request, isolating capacity reservation from the separate problem of locking a concurrent implementation.","repair":"Admit the complete batch only when its full size fits; otherwise preserve the existing queue unchanged.","root_cause":"Admission checks a single item or truncates work instead of reserving capacity for the complete batch.","sha256":"4f6f61999399feaa472ee8c35febc3de42c1f0fb5355be178771558870043f85","title":"A bounded queue admits only part of a logical batch · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":34.141,"exit_code":1,"observations":[{"actual":[[0,"a"],true],"check":"oversize batch is rejected intact","expected":[[0],false],"passed":false},{"actual":[[0,"a","b"],true],"check":"exact fit admitted","expected":[[0,"a","b"],true],"passed":true},{"actual":[[0],false],"check":"empty batch on full queue","expected":[[0],true],"passed":false},{"actual":[[],false],"check":"zero capacity empty batch","expected":[[],true],"passed":false},{"actual":[[],false],"check":"zero capacity nonempty batch","expected":[[],false],"passed":true},{"actual":[[0],true],"check":"oversize from empty","expected":[[],false],"passed":false},{"actual":[[0,1],true],"check":"room for small batch","expected":[[0,1],true],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oversize batch is rejected intact\", \"actual\": [[0, \"a\"], true], \"expected\": [[0], false], \"passed\": false}, {\"check\": \"exact fit admitted\", \"actual\": [[0, \"a\", \"b\"], true], \"expected\": [[0, \"a\", \"b\"], true], \"passed\": true}, {\"check\": \"empty batch on full queue\", \"actual\": [[0], false], \"expected\": [[0], true], \"passed\": false}, {\"check\": \"zero capacity empty batch\", \"actual\": [[], false], \"expected\": [[], true], \"passed\": false}, {\"check\": \"zero capacity nonempty batch\", \"actual\": [[], false], \"expected\": [[], false], \"passed\": true}, {\"check\": \"oversize from empty\", \"actual\": [[0], true], \"expected\": [[], false], \"passed\": false}, {\"check\": \"room for small batch\", \"actual\": [[0, 1], true], \"expected\": [[0, 1], true], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":32.277,"exit_code":1,"observations":[{"actual":[[0,"a","b"],true],"check":"oversize batch is rejected intact","expected":[[0],false],"passed":false},{"actual":[[0,"a","b"],true],"check":"exact fit admitted","expected":[[0,"a","b"],true],"passed":true},{"actual":[[0],false],"check":"empty batch on full queue","expected":[[0],true],"passed":false},{"actual":[[],false],"check":"zero capacity empty batch","expected":[[],true],"passed":false},{"actual":[[],false],"check":"zero capacity nonempty batch","expected":[[],false],"passed":true},{"actual":[[0,1],true],"check":"oversize from empty","expected":[[],false],"passed":false},{"actual":[[0,1],true],"check":"room for small batch","expected":[[0,1],true],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oversize batch is rejected intact\", \"actual\": [[0, \"a\", \"b\"], true], \"expected\": [[0], false], \"passed\": false}, {\"check\": \"exact fit admitted\", \"actual\": [[0, \"a\", \"b\"], true], \"expected\": [[0, \"a\", \"b\"], true], \"passed\": true}, {\"check\": \"empty batch on full queue\", \"actual\": [[0], false], \"expected\": [[0], true], \"passed\": false}, {\"check\": \"zero capacity empty batch\", \"actual\": [[], false], \"expected\": [[], true], \"passed\": false}, {\"check\": \"zero capacity nonempty batch\", \"actual\": [[], false], \"expected\": [[], false], \"passed\": true}, {\"check\": \"oversize from empty\", \"actual\": [[0, 1], true], \"expected\": [[], false], \"passed\": false}, {\"check\": \"room for small batch\", \"actual\": [[0, 1], true], \"expected\": [[0, 1], true], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":35.676,"exit_code":0,"observations":[{"actual":[[0],false],"check":"oversize batch is rejected intact","expected":[[0],false],"passed":true},{"actual":[[0,"a","b"],true],"check":"exact fit admitted","expected":[[0,"a","b"],true],"passed":true},{"actual":[[0],true],"check":"empty batch on full queue","expected":[[0],true],"passed":true},{"actual":[[],true],"check":"zero capacity empty batch","expected":[[],true],"passed":true},{"actual":[[],false],"check":"zero capacity nonempty batch","expected":[[],false],"passed":true},{"actual":[[],false],"check":"oversize from empty","expected":[[],false],"passed":true},{"actual":[[0,1],true],"check":"room for small batch","expected":[[0,1],true],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oversize batch is rejected intact\", \"actual\": [[0], false], \"expected\": [[0], false], \"passed\": true}, {\"check\": \"exact fit admitted\", \"actual\": [[0, \"a\", \"b\"], true], \"expected\": [[0, \"a\", \"b\"], true], \"passed\": true}, {\"check\": \"empty batch on full queue\", \"actual\": [[0], true], \"expected\": [[0], true], \"passed\": true}, {\"check\": \"zero capacity empty batch\", \"actual\": [[], true], \"expected\": [[], true], \"passed\": true}, {\"check\": \"zero capacity nonempty batch\", \"actual\": [[], false], \"expected\": [[], false], \"passed\": true}, {\"check\": \"oversize from empty\", \"actual\": [[], false], \"expected\": [[], false], \"passed\": true}, {\"check\": \"room for small batch\", \"actual\": [[0, 1], true], \"expected\": [[0, 1], true], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}