{"abstract":"Partial-read progress advances from the selected absolute start.","category":"HTTP ranges","checks":6,"contract":"Return the next absolute representation offset start+delivered; delivered counts body bytes only.","contract_signature":"start, delivered","evaluation_group":"s3-http_ranges-stream-transfer","failed_approach":"The partial repair uses return max(start,delivered), which still violates the stated contract.","family":"s3-http_ranges-stream-progress-absolute-offset","id":"FA-26551","implementations":{"attempt":{"sha256":"5bd49230c202a08e1aa8a92eb9c4a62d5fb7841d878d4451f651fd0d057b52f2","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(start, delivered):\n    return max(start,delivered)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('stream-progress-absolute-offset fixture 0', solve(2*N,N), 3*N)\ncheck('stream-progress-absolute-offset fixture 1', solve(N,0), N)\ncheck('stream-progress-absolute-offset fixture 2', solve(0,N), N)\ncheck('stream-progress-absolute-offset fixture 3', solve(0,0), 0)\ncheck('stream-progress-absolute-offset fixture 4', solve(N,2*N), 3*N)\ncheck('stream-progress-absolute-offset fixture 5', solve(3*N,4*N), 7*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":"2ef4b322d1457fe5098ad73fdc5b188f9b7d90326fb3fadbb106ccbe7a69fa2c","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(start, delivered):\n    return delivered\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('stream-progress-absolute-offset fixture 0', solve(2*N,N), 3*N)\ncheck('stream-progress-absolute-offset fixture 1', solve(N,0), N)\ncheck('stream-progress-absolute-offset fixture 2', solve(0,N), N)\ncheck('stream-progress-absolute-offset fixture 3', solve(0,0), 0)\ncheck('stream-progress-absolute-offset fixture 4', solve(N,2*N), 3*N)\ncheck('stream-progress-absolute-offset fixture 5', solve(3*N,4*N), 7*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-progress-absolute-offset","generated_at":"2026-09-29T14:41:16.932271+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 stream-progress-absolute-offset decision uses return delivered.","sha256":"c381d25013e48aa2a10c025c29ea91541c9114cd776549a18304449b4147be00","title":"Partial-read progress advances from the selected absolute start · 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":39.758,"exit_code":1,"observations":[{"actual":2,"check":"stream-progress-absolute-offset fixture 0","expected":3,"passed":false},{"actual":1,"check":"stream-progress-absolute-offset fixture 1","expected":1,"passed":true},{"actual":1,"check":"stream-progress-absolute-offset fixture 2","expected":1,"passed":true},{"actual":0,"check":"stream-progress-absolute-offset fixture 3","expected":0,"passed":true},{"actual":2,"check":"stream-progress-absolute-offset fixture 4","expected":3,"passed":false},{"actual":4,"check":"stream-progress-absolute-offset fixture 5","expected":7,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"stream-progress-absolute-offset fixture 0\", \"actual\": 2, \"expected\": 3, \"passed\": false}, {\"check\": \"stream-progress-absolute-offset fixture 1\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"stream-progress-absolute-offset fixture 2\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"stream-progress-absolute-offset fixture 3\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"stream-progress-absolute-offset fixture 4\", \"actual\": 2, \"expected\": 3, \"passed\": false}, {\"check\": \"stream-progress-absolute-offset fixture 5\", \"actual\": 4, \"expected\": 7, \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.992,"exit_code":1,"observations":[{"actual":1,"check":"stream-progress-absolute-offset fixture 0","expected":3,"passed":false},{"actual":0,"check":"stream-progress-absolute-offset fixture 1","expected":1,"passed":false},{"actual":1,"check":"stream-progress-absolute-offset fixture 2","expected":1,"passed":true},{"actual":0,"check":"stream-progress-absolute-offset fixture 3","expected":0,"passed":true},{"actual":2,"check":"stream-progress-absolute-offset fixture 4","expected":3,"passed":false},{"actual":4,"check":"stream-progress-absolute-offset fixture 5","expected":7,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"stream-progress-absolute-offset fixture 0\", \"actual\": 1, \"expected\": 3, \"passed\": false}, {\"check\": \"stream-progress-absolute-offset fixture 1\", \"actual\": 0, \"expected\": 1, \"passed\": false}, {\"check\": \"stream-progress-absolute-offset fixture 2\", \"actual\": 1, \"expected\": 1, \"passed\": true}, {\"check\": \"stream-progress-absolute-offset fixture 3\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"stream-progress-absolute-offset fixture 4\", \"actual\": 2, \"expected\": 3, \"passed\": false}, {\"check\": \"stream-progress-absolute-offset fixture 5\", \"actual\": 4, \"expected\": 7, \"passed\": false}], \"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."}}