{"abstract":"A structured table violates the declared record or column contract.","category":"Delimited text","checks":11,"contract":"Read concatenated decimal-length:payload, cells, where length counts Unicode code points in this stipulated text format. Lengths are nonempty canonical ASCII decimal, including zero; payload may contain commas and colons. A terminal comma is mandatory after each payload. Return cells or null for malformed input.","contract_signature":"data","evaluation_group":"s3-delimited-text-length-prefixed-cells","failed_approach":"The alternate implementation still violates the same declared invariant: leading-zero length fields are silently accepted.","family":"s3-delimited-text-length-prefixed-cells-canonical-length","id":"FA-48256","implementations":{"attempt":{"sha256":"86ddf167d4ff37b02a1ed87bb907934c3b985e240edda6d3810b62285b6d7dbf","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    out=[]; pos=0\n    while pos<len(data):\n        colon=data.find(':',pos)\n        if colon<0: return None\n        token=data[pos:colon]\n        if not token.isascii() or not token.isdecimal() or (len(token)>2 and token.startswith('0')): return None\n        size=int(token); begin=colon+1; end=begin+size\n        if end>=len(data) or data[end]!=',': return None\n        out.append(data[begin:end])\n        pos=end+1\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('two', solve(_vary('1:a,3:x,y,')), _vary(['a', 'x,y']))\ncheck('colon payload', solve(_vary('3:a:b,')), _vary(['a:b']))\ncheck('zero', solve(_vary('0:,')), _vary(['']))\ncheck('unicode', solve(_vary('1:é,')), _vary(['é']))\ncheck('truncated', solve(_vary('4:ab,')), _vary(None))\ncheck('missing terminator', solve(_vary('1:a')), _vary(None))\ncheck('leading zero', solve(_vary('01:a,')), _vary(None))\ncheck('trailing junk', solve(_vary('1:a,x')), _vary(None))\ncheck('zero stream', solve(_vary('')), _vary([]))\ncheck('multi digit', solve(_vary('10:abcdefghij,')), _vary(['abcdefghij']))\ncheck('variant payload extent', solve(str(N)+':'+('x'*N)+','), ['x'*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":"1c7e6d1b2421ad5187445326d466c33adbb419a358dace26f7e88eba74fcbab0","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    out=[]; pos=0\n    while pos<len(data):\n        colon=data.find(':',pos)\n        if colon<0: return None\n        token=data[pos:colon]\n        if not token.isascii() or not token.isdecimal() : return None\n        size=int(token); begin=colon+1; end=begin+size\n        if end>=len(data) or data[end]!=',': return None\n        out.append(data[begin:end])\n        pos=end+1\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('two', solve(_vary('1:a,3:x,y,')), _vary(['a', 'x,y']))\ncheck('colon payload', solve(_vary('3:a:b,')), _vary(['a:b']))\ncheck('zero', solve(_vary('0:,')), _vary(['']))\ncheck('unicode', solve(_vary('1:é,')), _vary(['é']))\ncheck('truncated', solve(_vary('4:ab,')), _vary(None))\ncheck('missing terminator', solve(_vary('1:a')), _vary(None))\ncheck('leading zero', solve(_vary('01:a,')), _vary(None))\ncheck('trailing junk', solve(_vary('1:a,x')), _vary(None))\ncheck('zero stream', solve(_vary('')), _vary([]))\ncheck('multi digit', solve(_vary('10:abcdefghij,')), _vary(['abcdefghij']))\ncheck('variant payload extent', solve(str(N)+':'+('x'*N)+','), ['x'*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":"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-length-prefixed-cells-canonical-length","generated_at":"2026-09-29T14:44:49.230268+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":"Leading-zero length fields are silently accepted.","sha256":"f3b1def4e31841cf9d98a1de8e9970888796713ebbdd9d546cf59af039358ee1","title":"Leading-zero length fields are silently accepted · 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":41.244,"exit_code":1,"observations":[{"actual":["a","x,y"],"check":"two","expected":["a","x,y"],"passed":true},{"actual":["a:b"],"check":"colon payload","expected":["a:b"],"passed":true},{"actual":[""],"check":"zero","expected":[""],"passed":true},{"actual":["é"],"check":"unicode","expected":["é"],"passed":true},{"actual":null,"check":"truncated","expected":null,"passed":true},{"actual":null,"check":"missing terminator","expected":null,"passed":true},{"actual":["a"],"check":"leading zero","expected":null,"passed":false},{"actual":null,"check":"trailing junk","expected":null,"passed":true},{"actual":[],"check":"zero stream","expected":[],"passed":true},{"actual":["abcdefghij"],"check":"multi digit","expected":["abcdefghij"],"passed":true},{"actual":["x"],"check":"variant payload extent","expected":["x"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"two\", \"actual\": [\"a\", \"x,y\"], \"expected\": [\"a\", \"x,y\"], \"passed\": true}, {\"check\": \"colon payload\", \"actual\": [\"a:b\"], \"expected\": [\"a:b\"], \"passed\": true}, {\"check\": \"zero\", \"actual\": [\"\"], \"expected\": [\"\"], \"passed\": true}, {\"check\": \"unicode\", \"actual\": [\"é\"], \"expected\": [\"é\"], \"passed\": true}, {\"check\": \"truncated\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"missing terminator\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"leading zero\", \"actual\": [\"a\"], \"expected\": null, \"passed\": false}, {\"check\": \"trailing junk\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"zero stream\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"multi digit\", \"actual\": [\"abcdefghij\"], \"expected\": [\"abcdefghij\"], \"passed\": true}, {\"check\": \"variant payload extent\", \"actual\": [\"x\"], \"expected\": [\"x\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.179,"exit_code":1,"observations":[{"actual":["a","x,y"],"check":"two","expected":["a","x,y"],"passed":true},{"actual":["a:b"],"check":"colon payload","expected":["a:b"],"passed":true},{"actual":[""],"check":"zero","expected":[""],"passed":true},{"actual":["é"],"check":"unicode","expected":["é"],"passed":true},{"actual":null,"check":"truncated","expected":null,"passed":true},{"actual":null,"check":"missing terminator","expected":null,"passed":true},{"actual":["a"],"check":"leading zero","expected":null,"passed":false},{"actual":null,"check":"trailing junk","expected":null,"passed":true},{"actual":[],"check":"zero stream","expected":[],"passed":true},{"actual":["abcdefghij"],"check":"multi digit","expected":["abcdefghij"],"passed":true},{"actual":["x"],"check":"variant payload extent","expected":["x"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"two\", \"actual\": [\"a\", \"x,y\"], \"expected\": [\"a\", \"x,y\"], \"passed\": true}, {\"check\": \"colon payload\", \"actual\": [\"a:b\"], \"expected\": [\"a:b\"], \"passed\": true}, {\"check\": \"zero\", \"actual\": [\"\"], \"expected\": [\"\"], \"passed\": true}, {\"check\": \"unicode\", \"actual\": [\"é\"], \"expected\": [\"é\"], \"passed\": true}, {\"check\": \"truncated\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"missing terminator\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"leading zero\", \"actual\": [\"a\"], \"expected\": null, \"passed\": false}, {\"check\": \"trailing junk\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"zero stream\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"multi digit\", \"actual\": [\"abcdefghij\"], \"expected\": [\"abcdefghij\"], \"passed\": true}, {\"check\": \"variant payload extent\", \"actual\": [\"x\"], \"expected\": [\"x\"], \"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."}}