{"abstract":"Multipart framing bytes do not advance the representation cursor.","category":"HTTP ranges","checks":6,"contract":"Return representation cursor after payload writes; framing bytes are tracked by the transport separately.","evaluation_group":"s3-http_ranges-stream-transfer","failed_approach":"The partial repair uses return offset+max(payload_written,framing_written), which still violates the stated contract.","family":"s3-http_ranges-stream-framing-not-progress","id":"FA-26556","implementations":{"attempt":{"sha256":"391ec7d5fb283aefbeb68985549661bd22cfbf4c0f2af971cd477d233fdca049","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(offset, payload_written, framing_written):\n    return offset+max(payload_written,framing_written)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('stream-framing-not-progress fixture 0', solve(N,N,3*N), 2*N)\ncheck('stream-framing-not-progress fixture 1', solve(N,0,N), N)\ncheck('stream-framing-not-progress fixture 2', solve(N,N,0), 2*N)\ncheck('stream-framing-not-progress fixture 3', solve(0,0,0), 0)\ncheck('stream-framing-not-progress fixture 4', solve(0,2*N,N), 2*N)\ncheck('stream-framing-not-progress fixture 5', solve(3*N,N,N), 4*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":"b17b05f8fc98b6095b9bbdba556f7683745f3d697653bc3235d14758bb53dfc8","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(offset, payload_written, framing_written):\n    return offset+payload_written+framing_written\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('stream-framing-not-progress fixture 0', solve(N,N,3*N), 2*N)\ncheck('stream-framing-not-progress fixture 1', solve(N,0,N), N)\ncheck('stream-framing-not-progress fixture 2', solve(N,N,0), 2*N)\ncheck('stream-framing-not-progress fixture 3', solve(0,0,0), 0)\ncheck('stream-framing-not-progress fixture 4', solve(0,2*N,N), 2*N)\ncheck('stream-framing-not-progress fixture 5', solve(3*N,N,N), 4*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"},"fixed":{"sha256":"32dcf440d06a628ebbfb56a1d150f362c05534a2e9aca807f6c0317dd7efa935","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(offset, payload_written, framing_written):\n    return offset+payload_written\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('stream-framing-not-progress fixture 0', solve(N,N,3*N), 2*N)\ncheck('stream-framing-not-progress fixture 1', solve(N,0,N), N)\ncheck('stream-framing-not-progress fixture 2', solve(N,N,0), 2*N)\ncheck('stream-framing-not-progress fixture 3', solve(0,0,0), 0)\ncheck('stream-framing-not-progress fixture 4', solve(0,2*N,N), 2*N)\ncheck('stream-framing-not-progress fixture 5', solve(3*N,N,N), 4*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 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-stream-framing-not-progress","generated_at":"2026-09-29T14:41:17.016368+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.","repair":"Apply the bounded decision exactly: return offset+payload_written","root_cause":"The stream-framing-not-progress decision uses return offset+payload_written+framing_written.","sha256":"245f1103d47c204e02dff6ce74167ee186a7119d52226575e1e6ca8b21d3c85e","title":"Multipart framing bytes do not advance the representation cursor · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":40.341,"exit_code":1,"observations":[{"actual":4,"check":"stream-framing-not-progress fixture 0","expected":2,"passed":false},{"actual":2,"check":"stream-framing-not-progress fixture 1","expected":1,"passed":false},{"actual":2,"check":"stream-framing-not-progress fixture 2","expected":2,"passed":true},{"actual":0,"check":"stream-framing-not-progress fixture 3","expected":0,"passed":true},{"actual":2,"check":"stream-framing-not-progress fixture 4","expected":2,"passed":true},{"actual":4,"check":"stream-framing-not-progress fixture 5","expected":4,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"stream-framing-not-progress fixture 0\", \"actual\": 4, \"expected\": 2, \"passed\": false}, {\"check\": \"stream-framing-not-progress fixture 1\", \"actual\": 2, \"expected\": 1, \"passed\": false}, {\"check\": \"stream-framing-not-progress fixture 2\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 3\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 4\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 5\", \"actual\": 4, \"expected\": 4, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.194,"exit_code":1,"observations":[{"actual":5,"check":"stream-framing-not-progress fixture 0","expected":2,"passed":false},{"actual":2,"check":"stream-framing-not-progress fixture 1","expected":1,"passed":false},{"actual":2,"check":"stream-framing-not-progress fixture 2","expected":2,"passed":true},{"actual":0,"check":"stream-framing-not-progress fixture 3","expected":0,"passed":true},{"actual":3,"check":"stream-framing-not-progress fixture 4","expected":2,"passed":false},{"actual":5,"check":"stream-framing-not-progress fixture 5","expected":4,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"stream-framing-not-progress fixture 0\", \"actual\": 5, \"expected\": 2, \"passed\": false}, {\"check\": \"stream-framing-not-progress fixture 1\", \"actual\": 2, \"expected\": 1, \"passed\": false}, {\"check\": \"stream-framing-not-progress fixture 2\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 3\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 4\", \"actual\": 3, \"expected\": 2, \"passed\": false}, {\"check\": \"stream-framing-not-progress fixture 5\", \"actual\": 5, \"expected\": 4, \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.514,"exit_code":0,"observations":[{"actual":2,"check":"stream-framing-not-progress fixture 0","expected":2,"passed":true},{"actual":1,"check":"stream-framing-not-progress fixture 1","expected":1,"passed":true},{"actual":2,"check":"stream-framing-not-progress fixture 2","expected":2,"passed":true},{"actual":0,"check":"stream-framing-not-progress fixture 3","expected":0,"passed":true},{"actual":2,"check":"stream-framing-not-progress fixture 4","expected":2,"passed":true},{"actual":4,"check":"stream-framing-not-progress fixture 5","expected":4,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"stream-framing-not-progress fixture 0\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 1\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 2\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 3\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 4\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"stream-framing-not-progress fixture 5\", \"actual\": 4, \"expected\": 4, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}