{"abstract":"Part headers end at the first double CRLF.","category":"HTTP ranges","checks":6,"contract":"Split buffered part at the first CRLFCRLF into [header,body], or None if incomplete. Body may contain additional double CRLF sequences.","contract_signature":"data","evaluation_group":"s3-http_ranges-multipart-client","failed_approach":"The partial repair uses p=data.find(\"\\r\\n\")\nreturn [data[:p],data[p+2:]] if p>=0 else None, which still violates the stated contract.","family":"s3-http_ranges-multipart-client-header-terminator","id":"FA-26806","implementations":{"attempt":{"sha256":"416db51a2d4f4cca5b382a14ae298ee6d4ce2743a3135e947ad2a2f1b993c44a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(data):\n    p=data.find(\"\\r\\n\")\n    return [data[:p],data[p+2:]] if p>=0 else None\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('multipart-client-header-terminator fixture 0', solve(\"H\\r\\n\\r\\n\"+\"p\"*N+\"\\r\\n\\r\\nX\"), [\"H\",\"p\"*N+\"\\r\\n\\r\\nX\"])\ncheck('multipart-client-header-terminator fixture 1', solve(\"H\\r\\nX\"), None)\ncheck('multipart-client-header-terminator fixture 2', solve(\"H\\r\\n\\r\\nP\"), [\"H\",\"P\"])\ncheck('multipart-client-header-terminator fixture 3', solve(\"\\r\\n\\r\\n\"), [\"\",\"\"])\ncheck('multipart-client-header-terminator fixture 4', solve(\"\"), None)\ncheck('multipart-client-header-terminator fixture 5', solve(\"A\\r\\nB\\r\\n\\r\\nP\"), [\"A\\r\\nB\",\"P\"])\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":"7cadbfd6b544dd2be21bf49ffcae306a49ca0d550044e95f6ddd95d735c697d1","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(data):\n    p=data.rfind(\"\\r\\n\\r\\n\")\n    return [data[:p],data[p+4:]] if p>=0 else None\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('multipart-client-header-terminator fixture 0', solve(\"H\\r\\n\\r\\n\"+\"p\"*N+\"\\r\\n\\r\\nX\"), [\"H\",\"p\"*N+\"\\r\\n\\r\\nX\"])\ncheck('multipart-client-header-terminator fixture 1', solve(\"H\\r\\nX\"), None)\ncheck('multipart-client-header-terminator fixture 2', solve(\"H\\r\\n\\r\\nP\"), [\"H\",\"P\"])\ncheck('multipart-client-header-terminator fixture 3', solve(\"\\r\\n\\r\\n\"), [\"\",\"\"])\ncheck('multipart-client-header-terminator fixture 4', solve(\"\"), None)\ncheck('multipart-client-header-terminator fixture 5', solve(\"A\\r\\nB\\r\\n\\r\\nP\"), [\"A\\r\\nB\",\"P\"])\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 simplified range service, with stipulated local policies and already parsed trusted inputs; not a complete HTTP implementation. 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-http_ranges-multipart-client-header-terminator","generated_at":"2026-09-29T14:41:19.344771+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Range responses combine representation identity, conditional requests, framing, and partial-object state.","root_cause":"The multipart-client-header-terminator decision uses p=data.rfind(\"\\r\\n\\r\\n\")\nreturn [data[:p],data[p+4:]] if p>=0 else None.","sha256":"791ba866fd4162eb81ef5cc138b3eaec95fc050a16aa75102f356507e92b4138","title":"Part headers end at the first double CRLF · 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":37.493,"exit_code":1,"observations":[{"actual":["H","\r\np\r\n\r\nX"],"check":"multipart-client-header-terminator fixture 0","expected":["H","p\r\n\r\nX"],"passed":false},{"actual":["H","X"],"check":"multipart-client-header-terminator fixture 1","expected":null,"passed":false},{"actual":["H","\r\nP"],"check":"multipart-client-header-terminator fixture 2","expected":["H","P"],"passed":false},{"actual":["","\r\n"],"check":"multipart-client-header-terminator fixture 3","expected":["",""],"passed":false},{"actual":null,"check":"multipart-client-header-terminator fixture 4","expected":null,"passed":true},{"actual":["A","B\r\n\r\nP"],"check":"multipart-client-header-terminator fixture 5","expected":["A\r\nB","P"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"multipart-client-header-terminator fixture 0\", \"actual\": [\"H\", \"\\r\\np\\r\\n\\r\\nX\"], \"expected\": [\"H\", \"p\\r\\n\\r\\nX\"], \"passed\": false}, {\"check\": \"multipart-client-header-terminator fixture 1\", \"actual\": [\"H\", \"X\"], \"expected\": null, \"passed\": false}, {\"check\": \"multipart-client-header-terminator fixture 2\", \"actual\": [\"H\", \"\\r\\nP\"], \"expected\": [\"H\", \"P\"], \"passed\": false}, {\"check\": \"multipart-client-header-terminator fixture 3\", \"actual\": [\"\", \"\\r\\n\"], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"multipart-client-header-terminator fixture 4\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"multipart-client-header-terminator fixture 5\", \"actual\": [\"A\", \"B\\r\\n\\r\\nP\"], \"expected\": [\"A\\r\\nB\", \"P\"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.534,"exit_code":1,"observations":[{"actual":["H\r\n\r\np","X"],"check":"multipart-client-header-terminator fixture 0","expected":["H","p\r\n\r\nX"],"passed":false},{"actual":null,"check":"multipart-client-header-terminator fixture 1","expected":null,"passed":true},{"actual":["H","P"],"check":"multipart-client-header-terminator fixture 2","expected":["H","P"],"passed":true},{"actual":["",""],"check":"multipart-client-header-terminator fixture 3","expected":["",""],"passed":true},{"actual":null,"check":"multipart-client-header-terminator fixture 4","expected":null,"passed":true},{"actual":["A\r\nB","P"],"check":"multipart-client-header-terminator fixture 5","expected":["A\r\nB","P"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"multipart-client-header-terminator fixture 0\", \"actual\": [\"H\\r\\n\\r\\np\", \"X\"], \"expected\": [\"H\", \"p\\r\\n\\r\\nX\"], \"passed\": false}, {\"check\": \"multipart-client-header-terminator fixture 1\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"multipart-client-header-terminator fixture 2\", \"actual\": [\"H\", \"P\"], \"expected\": [\"H\", \"P\"], \"passed\": true}, {\"check\": \"multipart-client-header-terminator fixture 3\", \"actual\": [\"\", \"\"], \"expected\": [\"\", \"\"], \"passed\": true}, {\"check\": \"multipart-client-header-terminator fixture 4\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"multipart-client-header-terminator fixture 5\", \"actual\": [\"A\\r\\nB\", \"P\"], \"expected\": [\"A\\r\\nB\", \"P\"], \"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."}}