{"abstract":"A suffix classifier chooses a shorter compound extension.","category":"Tokenization","checks":4,"contract":"Return .tar.gz, .gz or .txt if present, preferring longest.","contract_signature":"x","evaluation_group":"model-063cc7406844503b","failed_approach":"The attempted repair handles the primary example but still violates a separate boundary of the same contract.","family":"xp-suffix-longest","id":"FA-3881","implementations":{"attempt":{"sha256":"5f483da34592818d45efd8e2b408e82827f1c1960f8ca8a9cc32dcbf7540cb44","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct\nfrom urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit\nfrom email.header import decode_header, make_header\nfrom email.utils import getaddresses\nfrom xml.etree import ElementTree as ET\nimport shlex, string, textwrap\n\nN = 1\nobservations = []\ndef solve(x):\n    try:\n        return '.'+x.rsplit('.',1)[1] if '.' in x else None\n    except Exception as exc:\n        return {\"error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('boundary 1', solve('a.tar.gz'), '.tar.gz')\ncheck('boundary 2', solve('a.gz'), '.gz')\ncheck('boundary 3', solve('a.bin'), None)\ncheck('boundary 4', solve('a.txt'), '.txt')\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":"cf4f5fda8940edf3aea1ca7bff45d3130b822666e0012b79a1547250455852f2","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct\nfrom urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit\nfrom email.header import decode_header, make_header\nfrom email.utils import getaddresses\nfrom xml.etree import ElementTree as ET\nimport shlex, string, textwrap\n\nN = 1\nobservations = []\ndef solve(x):\n    try:\n        return next((p for p in ('.gz','.tar.gz','.txt') if x.endswith(p)),None)\n    except Exception as exc:\n        return {\"error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('boundary 1', solve('a.tar.gz'), '.tar.gz')\ncheck('boundary 2', solve('a.gz'), '.gz')\ncheck('boundary 3', solve('a.bin'), None)\ncheck('boundary 4', solve('a.txt'), '.txt')\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":"xp-suffix-longest","generated_at":"2026-09-29T14:37:32.306724+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A local executable model for consumers of structured text; oracle values are authored literals, not outputs copied from the repaired implementation.","root_cause":"The implementation applies an operation whose text or grammar semantics violate this contract: Return .tar.gz, .gz or .txt if present, preferring longest.","sha256":"8692330cf67afba0b7eda753ecfeb72809650fb4c42f5f0d459d6b95a6b28e67","title":"A suffix classifier chooses a shorter compound extension · 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":55.499,"exit_code":1,"observations":[{"actual":".gz","check":"boundary 1","expected":".tar.gz","passed":false},{"actual":".gz","check":"boundary 2","expected":".gz","passed":true},{"actual":".bin","check":"boundary 3","expected":null,"passed":false},{"actual":".txt","check":"boundary 4","expected":".txt","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": \".gz\", \"expected\": \".tar.gz\", \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": \".gz\", \"expected\": \".gz\", \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": \".bin\", \"expected\": null, \"passed\": false}, {\"check\": \"boundary 4\", \"actual\": \".txt\", \"expected\": \".txt\", \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":159.426,"exit_code":1,"observations":[{"actual":".gz","check":"boundary 1","expected":".tar.gz","passed":false},{"actual":".gz","check":"boundary 2","expected":".gz","passed":true},{"actual":null,"check":"boundary 3","expected":null,"passed":true},{"actual":".txt","check":"boundary 4","expected":".txt","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": \".gz\", \"expected\": \".tar.gz\", \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": \".gz\", \"expected\": \".gz\", \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": \".txt\", \"expected\": \".txt\", \"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."}}