{"abstract":"A structured table violates the declared record or column contract.","category":"Delimited text","checks":8,"contract":"Split a simple unquoted comma record and return [value,start,end] for each field, using zero-based Unicode-code-point offsets and exclusive ends. Delimiters are outside field spans; empty fields have equal start/end positions. The input contains no record terminator.","evaluation_group":"s3-delimited-text-field-source-spans","failed_approach":"The alternate implementation still violates the same declared invariant: a field span is paired with the entire unsplit record.","family":"s3-delimited-text-field-source-spans-span-value","id":"FA-48731","implementations":{"attempt":{"sha256":"c620761b62b4209709140d83212e52fdfe701163bbd00a8ebe0a08675df15c96","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    fields=[]; start=0\n    for position,ch in enumerate(data):\n        if ch==',':\n            fields.append([data[:position],start,position])\n            start=position+1\n    fields.append([data[start:],start,len(data)])\n    return fields\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('normal', solve(_vary('ab,c')), _vary([['ab', 0, 2], ['c', 3, 4]]))\ncheck('empty edges', solve(_vary(',a,')), _vary([['', 0, 0], ['a', 1, 2], ['', 3, 3]]))\ncheck('empty input', solve(_vary('')), _vary([['', 0, 0]]))\ncheck('unicode', solve(_vary('é,😀')), _vary([['é', 0, 1], ['😀', 2, 3]]))\ncheck('many empties', solve(_vary(',,')), _vary([['', 0, 0], ['', 1, 1], ['', 2, 2]]))\ncheck('one', solve(_vary('abcd')), _vary([['abcd', 0, 4]]))\ncheck('middle empty', solve(_vary('a,,b')), _vary([['a', 0, 1], ['', 2, 2], ['b', 3, 4]]))\ncheck('variant source extent', solve(('x'*N)+',y'), [['x'*N,0,N],['y',N+1,N+2]])\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":"800f7b242b7c88a6dcc74e0c27db2263cfaadc1f65422baeb8c25ad0cf733c2b","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    fields=[]; start=0\n    for position,ch in enumerate(data):\n        if ch==',':\n            fields.append([data,start,position])\n            start=position+1\n    fields.append([data[start:],start,len(data)])\n    return fields\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('normal', solve(_vary('ab,c')), _vary([['ab', 0, 2], ['c', 3, 4]]))\ncheck('empty edges', solve(_vary(',a,')), _vary([['', 0, 0], ['a', 1, 2], ['', 3, 3]]))\ncheck('empty input', solve(_vary('')), _vary([['', 0, 0]]))\ncheck('unicode', solve(_vary('é,😀')), _vary([['é', 0, 1], ['😀', 2, 3]]))\ncheck('many empties', solve(_vary(',,')), _vary([['', 0, 0], ['', 1, 1], ['', 2, 2]]))\ncheck('one', solve(_vary('abcd')), _vary([['abcd', 0, 4]]))\ncheck('middle empty', solve(_vary('a,,b')), _vary([['a', 0, 1], ['', 2, 2], ['b', 3, 4]]))\ncheck('variant source extent', solve(('x'*N)+',y'), [['x'*N,0,N],['y',N+1,N+2]])\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":"36d88f5387bcb781d1af648c07014ef487be5bdb8e70990a67002beb75f82ffa","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    fields=[]; start=0\n    for position,ch in enumerate(data):\n        if ch==',':\n            fields.append([data[start:position],start,position])\n            start=position+1\n    fields.append([data[start:],start,len(data)])\n    return fields\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('normal', solve(_vary('ab,c')), _vary([['ab', 0, 2], ['c', 3, 4]]))\ncheck('empty edges', solve(_vary(',a,')), _vary([['', 0, 0], ['a', 1, 2], ['', 3, 3]]))\ncheck('empty input', solve(_vary('')), _vary([['', 0, 0]]))\ncheck('unicode', solve(_vary('é,😀')), _vary([['é', 0, 1], ['😀', 2, 3]]))\ncheck('many empties', solve(_vary(',,')), _vary([['', 0, 0], ['', 1, 1], ['', 2, 2]]))\ncheck('one', solve(_vary('abcd')), _vary([['abcd', 0, 4]]))\ncheck('middle empty', solve(_vary('a,,b')), _vary([['a', 0, 1], ['', 2, 2], ['b', 3, 4]]))\ncheck('variant source extent', solve(('x'*N)+',y'), [['x'*N,0,N],['y',N+1,N+2]])\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-field-source-spans-span-value","generated_at":"2026-09-29T14:44:53.423624+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.","repair":"Preserve the named invariant at the faulty decision: fields.append([data[start:position],start,position])","root_cause":"A field span is paired with the entire unsplit record.","sha256":"11c255bb837027b95bd45875979ca2af0439000178287ebbef2334f9339c181a","title":"A field span is paired with the entire unsplit record · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":39.333,"exit_code":1,"observations":[{"actual":[["ab",0,2],["c",3,4]],"check":"normal","expected":[["ab",0,2],["c",3,4]],"passed":true},{"actual":[["",0,0],[",a",1,2],["",3,3]],"check":"empty edges","expected":[["",0,0],["a",1,2],["",3,3]],"passed":false},{"actual":[["",0,0]],"check":"empty input","expected":[["",0,0]],"passed":true},{"actual":[["é",0,1],["😀",2,3]],"check":"unicode","expected":[["é",0,1],["😀",2,3]],"passed":true},{"actual":[["",0,0],[",",1,1],["",2,2]],"check":"many empties","expected":[["",0,0],["",1,1],["",2,2]],"passed":false},{"actual":[["abcd",0,4]],"check":"one","expected":[["abcd",0,4]],"passed":true},{"actual":[["a",0,1],["a,",2,2],["b",3,4]],"check":"middle empty","expected":[["a",0,1],["",2,2],["b",3,4]],"passed":false},{"actual":[["x",0,1],["y",2,3]],"check":"variant source extent","expected":[["x",0,1],["y",2,3]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"normal\", \"actual\": [[\"ab\", 0, 2], [\"c\", 3, 4]], \"expected\": [[\"ab\", 0, 2], [\"c\", 3, 4]], \"passed\": true}, {\"check\": \"empty edges\", \"actual\": [[\"\", 0, 0], [\",a\", 1, 2], [\"\", 3, 3]], \"expected\": [[\"\", 0, 0], [\"a\", 1, 2], [\"\", 3, 3]], \"passed\": false}, {\"check\": \"empty input\", \"actual\": [[\"\", 0, 0]], \"expected\": [[\"\", 0, 0]], \"passed\": true}, {\"check\": \"unicode\", \"actual\": [[\"é\", 0, 1], [\"😀\", 2, 3]], \"expected\": [[\"é\", 0, 1], [\"😀\", 2, 3]], \"passed\": true}, {\"check\": \"many empties\", \"actual\": [[\"\", 0, 0], [\",\", 1, 1], [\"\", 2, 2]], \"expected\": [[\"\", 0, 0], [\"\", 1, 1], [\"\", 2, 2]], \"passed\": false}, {\"check\": \"one\", \"actual\": [[\"abcd\", 0, 4]], \"expected\": [[\"abcd\", 0, 4]], \"passed\": true}, {\"check\": \"middle empty\", \"actual\": [[\"a\", 0, 1], [\"a,\", 2, 2], [\"b\", 3, 4]], \"expected\": [[\"a\", 0, 1], [\"\", 2, 2], [\"b\", 3, 4]], \"passed\": false}, {\"check\": \"variant source extent\", \"actual\": [[\"x\", 0, 1], [\"y\", 2, 3]], \"expected\": [[\"x\", 0, 1], [\"y\", 2, 3]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":37.975,"exit_code":1,"observations":[{"actual":[["ab,c",0,2],["c",3,4]],"check":"normal","expected":[["ab",0,2],["c",3,4]],"passed":false},{"actual":[[",a,",0,0],[",a,",1,2],["",3,3]],"check":"empty edges","expected":[["",0,0],["a",1,2],["",3,3]],"passed":false},{"actual":[["",0,0]],"check":"empty input","expected":[["",0,0]],"passed":true},{"actual":[["é,😀",0,1],["😀",2,3]],"check":"unicode","expected":[["é",0,1],["😀",2,3]],"passed":false},{"actual":[[",,",0,0],[",,",1,1],["",2,2]],"check":"many empties","expected":[["",0,0],["",1,1],["",2,2]],"passed":false},{"actual":[["abcd",0,4]],"check":"one","expected":[["abcd",0,4]],"passed":true},{"actual":[["a,,b",0,1],["a,,b",2,2],["b",3,4]],"check":"middle empty","expected":[["a",0,1],["",2,2],["b",3,4]],"passed":false},{"actual":[["x,y",0,1],["y",2,3]],"check":"variant source extent","expected":[["x",0,1],["y",2,3]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"normal\", \"actual\": [[\"ab,c\", 0, 2], [\"c\", 3, 4]], \"expected\": [[\"ab\", 0, 2], [\"c\", 3, 4]], \"passed\": false}, {\"check\": \"empty edges\", \"actual\": [[\",a,\", 0, 0], [\",a,\", 1, 2], [\"\", 3, 3]], \"expected\": [[\"\", 0, 0], [\"a\", 1, 2], [\"\", 3, 3]], \"passed\": false}, {\"check\": \"empty input\", \"actual\": [[\"\", 0, 0]], \"expected\": [[\"\", 0, 0]], \"passed\": true}, {\"check\": \"unicode\", \"actual\": [[\"é,😀\", 0, 1], [\"😀\", 2, 3]], \"expected\": [[\"é\", 0, 1], [\"😀\", 2, 3]], \"passed\": false}, {\"check\": \"many empties\", \"actual\": [[\",,\", 0, 0], [\",,\", 1, 1], [\"\", 2, 2]], \"expected\": [[\"\", 0, 0], [\"\", 1, 1], [\"\", 2, 2]], \"passed\": false}, {\"check\": \"one\", \"actual\": [[\"abcd\", 0, 4]], \"expected\": [[\"abcd\", 0, 4]], \"passed\": true}, {\"check\": \"middle empty\", \"actual\": [[\"a,,b\", 0, 1], [\"a,,b\", 2, 2], [\"b\", 3, 4]], \"expected\": [[\"a\", 0, 1], [\"\", 2, 2], [\"b\", 3, 4]], \"passed\": false}, {\"check\": \"variant source extent\", \"actual\": [[\"x,y\", 0, 1], [\"y\", 2, 3]], \"expected\": [[\"x\", 0, 1], [\"y\", 2, 3]], \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.67,"exit_code":0,"observations":[{"actual":[["ab",0,2],["c",3,4]],"check":"normal","expected":[["ab",0,2],["c",3,4]],"passed":true},{"actual":[["",0,0],["a",1,2],["",3,3]],"check":"empty edges","expected":[["",0,0],["a",1,2],["",3,3]],"passed":true},{"actual":[["",0,0]],"check":"empty input","expected":[["",0,0]],"passed":true},{"actual":[["é",0,1],["😀",2,3]],"check":"unicode","expected":[["é",0,1],["😀",2,3]],"passed":true},{"actual":[["",0,0],["",1,1],["",2,2]],"check":"many empties","expected":[["",0,0],["",1,1],["",2,2]],"passed":true},{"actual":[["abcd",0,4]],"check":"one","expected":[["abcd",0,4]],"passed":true},{"actual":[["a",0,1],["",2,2],["b",3,4]],"check":"middle empty","expected":[["a",0,1],["",2,2],["b",3,4]],"passed":true},{"actual":[["x",0,1],["y",2,3]],"check":"variant source extent","expected":[["x",0,1],["y",2,3]],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"normal\", \"actual\": [[\"ab\", 0, 2], [\"c\", 3, 4]], \"expected\": [[\"ab\", 0, 2], [\"c\", 3, 4]], \"passed\": true}, {\"check\": \"empty edges\", \"actual\": [[\"\", 0, 0], [\"a\", 1, 2], [\"\", 3, 3]], \"expected\": [[\"\", 0, 0], [\"a\", 1, 2], [\"\", 3, 3]], \"passed\": true}, {\"check\": \"empty input\", \"actual\": [[\"\", 0, 0]], \"expected\": [[\"\", 0, 0]], \"passed\": true}, {\"check\": \"unicode\", \"actual\": [[\"é\", 0, 1], [\"😀\", 2, 3]], \"expected\": [[\"é\", 0, 1], [\"😀\", 2, 3]], \"passed\": true}, {\"check\": \"many empties\", \"actual\": [[\"\", 0, 0], [\"\", 1, 1], [\"\", 2, 2]], \"expected\": [[\"\", 0, 0], [\"\", 1, 1], [\"\", 2, 2]], \"passed\": true}, {\"check\": \"one\", \"actual\": [[\"abcd\", 0, 4]], \"expected\": [[\"abcd\", 0, 4]], \"passed\": true}, {\"check\": \"middle empty\", \"actual\": [[\"a\", 0, 1], [\"\", 2, 2], [\"b\", 3, 4]], \"expected\": [[\"a\", 0, 1], [\"\", 2, 2], [\"b\", 3, 4]], \"passed\": true}, {\"check\": \"variant source extent\", \"actual\": [[\"x\", 0, 1], [\"y\", 2, 3]], \"expected\": [[\"x\", 0, 1], [\"y\", 2, 3]], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}