{"abstract":"A structured table violates the declared record or column contract.","category":"Delimited text","checks":8,"contract":"Read semicolon rows in a schema where bare ^ copies the previous value in that column, ^^ represents literal ^, and ^! resets that column to null. A copy in the first row rejects. Exactly two columns are required; an explicit empty string replaces the previous value.","contract_signature":"data","evaluation_group":"s3-delimited-text-ditto-cells","failed_approach":"Using truthiness also ignores explicit empty-string replacements.","family":"s3-delimited-text-ditto-cells-reset-memory","id":"FA-47726","implementations":{"attempt":{"sha256":"27e0bfc53ce69eb3390f7375f69909ea9fef041165507f52159c2b1a6020c039","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\ndef _vary(value):\n    if value == '@END': return 3 + 4*N\n    if isinstance(value, str): return value.replace('@', 'cell' * N)\n    if isinstance(value, list): return [_vary(x) for x in value]\n    if isinstance(value, dict): return {_vary(k): _vary(v) for k,v in value.items()}\n    return value\nN = 1\nobservations = []\ndef solve(data):\n    rows, previous = [], None\n    for line in data:\n        cells = line.split(';')\n        if len(cells) != 2: return None\n        row = []\n        for i, cell in enumerate(cells):\n            if cell == '^':\n                if previous is None: return None\n                value = previous[i]\n            elif cell == '^^': value = '^'\n            elif cell == '^!': value = None\n            else: value = cell\n            row.append(value)\n        rows.append(row)\n        previous = [new if new else old for old,new in zip(previous or row,row)]\n    return rows\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('copy columns', solve(_vary(['@;a', '^;b', 'c;^'])), _vary([['@', 'a'], ['@', 'b'], ['c', 'b']]))\ncheck('first copy', solve(_vary(['^;x'])), _vary(None))\ncheck('literal marker', solve(_vary(['^^;@'])), _vary([['^', '@']]))\ncheck('null reset', solve(_vary(['@;a', '^!;^', '^;z'])), _vary([['@', 'a'], [None, 'a'], [None, 'z']]))\ncheck('empty replaces', solve(_vary(['@;a', ';b', '^;^'])), _vary([['@', 'a'], ['', 'b'], ['', 'b']]))\ncheck('wrong width', solve(_vary(['@'])), _vary(None))\ncheck('zero', solve(_vary([])), _vary([]))\ncheck('literal prefix', solve(_vary(['^x;@'])), _vary([['^x', '@']]))\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":"39d57f22a7da727d3c0bd7a605c0463324f8ae0ef0ae8dffc57dcd092ac96da4","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\ndef _vary(value):\n    if value == '@END': return 3 + 4*N\n    if isinstance(value, str): return value.replace('@', 'cell' * N)\n    if isinstance(value, list): return [_vary(x) for x in value]\n    if isinstance(value, dict): return {_vary(k): _vary(v) for k,v in value.items()}\n    return value\nN = 1\nobservations = []\ndef solve(data):\n    rows, previous = [], None\n    for line in data:\n        cells = line.split(';')\n        if len(cells) != 2: return None\n        row = []\n        for i, cell in enumerate(cells):\n            if cell == '^':\n                if previous is None: return None\n                value = previous[i]\n            elif cell == '^^': value = '^'\n            elif cell == '^!': value = None\n            else: value = cell\n            row.append(value)\n        rows.append(row)\n        previous = [old if new is None else new for old,new in zip(previous or row,row)]\n    return rows\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('copy columns', solve(_vary(['@;a', '^;b', 'c;^'])), _vary([['@', 'a'], ['@', 'b'], ['c', 'b']]))\ncheck('first copy', solve(_vary(['^;x'])), _vary(None))\ncheck('literal marker', solve(_vary(['^^;@'])), _vary([['^', '@']]))\ncheck('null reset', solve(_vary(['@;a', '^!;^', '^;z'])), _vary([['@', 'a'], [None, 'a'], [None, 'z']]))\ncheck('empty replaces', solve(_vary(['@;a', ';b', '^;^'])), _vary([['@', 'a'], ['', 'b'], ['', 'b']]))\ncheck('wrong width', solve(_vary(['@'])), _vary(None))\ncheck('zero', solve(_vary([])), _vary([]))\ncheck('literal prefix', solve(_vary(['^x;@'])), _vary([['^x', '@']]))\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":"Deterministic bounded in-memory model. No claim of complete CSV or external format 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-delimited-text-ditto-cells-reset-memory","generated_at":"2026-09-29T14:44:44.219819+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Delimited interchange needs explicit framing, schema and field semantics at ingestion and emission boundaries.","root_cause":"The previous-value snapshot ignores explicit null resets.","sha256":"87c5364797eb9fad746d7694572d7700741da0e4348702d3b3cfde6c7aa123c3","title":"A reset marker clears the current cell but not future inheritance · 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":42.521,"exit_code":1,"observations":[{"actual":[["cell","a"],["cell","b"],["c","b"]],"check":"copy columns","expected":[["cell","a"],["cell","b"],["c","b"]],"passed":true},{"actual":null,"check":"first copy","expected":null,"passed":true},{"actual":[["^","cell"]],"check":"literal marker","expected":[["^","cell"]],"passed":true},{"actual":[["cell","a"],[null,"a"],["cell","z"]],"check":"null reset","expected":[["cell","a"],[null,"a"],[null,"z"]],"passed":false},{"actual":[["cell","a"],["","b"],["cell","b"]],"check":"empty replaces","expected":[["cell","a"],["","b"],["","b"]],"passed":false},{"actual":null,"check":"wrong width","expected":null,"passed":true},{"actual":[],"check":"zero","expected":[],"passed":true},{"actual":[["^x","cell"]],"check":"literal prefix","expected":[["^x","cell"]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"copy columns\", \"actual\": [[\"cell\", \"a\"], [\"cell\", \"b\"], [\"c\", \"b\"]], \"expected\": [[\"cell\", \"a\"], [\"cell\", \"b\"], [\"c\", \"b\"]], \"passed\": true}, {\"check\": \"first copy\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"literal marker\", \"actual\": [[\"^\", \"cell\"]], \"expected\": [[\"^\", \"cell\"]], \"passed\": true}, {\"check\": \"null reset\", \"actual\": [[\"cell\", \"a\"], [null, \"a\"], [\"cell\", \"z\"]], \"expected\": [[\"cell\", \"a\"], [null, \"a\"], [null, \"z\"]], \"passed\": false}, {\"check\": \"empty replaces\", \"actual\": [[\"cell\", \"a\"], [\"\", \"b\"], [\"cell\", \"b\"]], \"expected\": [[\"cell\", \"a\"], [\"\", \"b\"], [\"\", \"b\"]], \"passed\": false}, {\"check\": \"wrong width\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"zero\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"literal prefix\", \"actual\": [[\"^x\", \"cell\"]], \"expected\": [[\"^x\", \"cell\"]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.713,"exit_code":1,"observations":[{"actual":[["cell","a"],["cell","b"],["c","b"]],"check":"copy columns","expected":[["cell","a"],["cell","b"],["c","b"]],"passed":true},{"actual":null,"check":"first copy","expected":null,"passed":true},{"actual":[["^","cell"]],"check":"literal marker","expected":[["^","cell"]],"passed":true},{"actual":[["cell","a"],[null,"a"],["cell","z"]],"check":"null reset","expected":[["cell","a"],[null,"a"],[null,"z"]],"passed":false},{"actual":[["cell","a"],["","b"],["","b"]],"check":"empty replaces","expected":[["cell","a"],["","b"],["","b"]],"passed":true},{"actual":null,"check":"wrong width","expected":null,"passed":true},{"actual":[],"check":"zero","expected":[],"passed":true},{"actual":[["^x","cell"]],"check":"literal prefix","expected":[["^x","cell"]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"copy columns\", \"actual\": [[\"cell\", \"a\"], [\"cell\", \"b\"], [\"c\", \"b\"]], \"expected\": [[\"cell\", \"a\"], [\"cell\", \"b\"], [\"c\", \"b\"]], \"passed\": true}, {\"check\": \"first copy\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"literal marker\", \"actual\": [[\"^\", \"cell\"]], \"expected\": [[\"^\", \"cell\"]], \"passed\": true}, {\"check\": \"null reset\", \"actual\": [[\"cell\", \"a\"], [null, \"a\"], [\"cell\", \"z\"]], \"expected\": [[\"cell\", \"a\"], [null, \"a\"], [null, \"z\"]], \"passed\": false}, {\"check\": \"empty replaces\", \"actual\": [[\"cell\", \"a\"], [\"\", \"b\"], [\"\", \"b\"]], \"expected\": [[\"cell\", \"a\"], [\"\", \"b\"], [\"\", \"b\"]], \"passed\": true}, {\"check\": \"wrong width\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"zero\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"literal prefix\", \"actual\": [[\"^x\", \"cell\"]], \"expected\": [[\"^x\", \"cell\"]], \"passed\": true}], \"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."}}