{"abstract":"Numeric download order fills old segments before the seek target.","category":"Streaming segment lifecycle","checks":4,"contract":"Prioritize known sequence IDs by distance from seek target; at equal distance prefer forward data, then numeric ID.","contract_signature":"sequences, target","evaluation_group":"xmed-segment-priority-seek-distance","failed_approach":"Stable distance-only sorting may prioritize backward data on a tie.","family":"xmed-segment-priority-seek-distance","id":"FA-11186","implementations":{"attempt":{"sha256":"64d9657ee9afc7853f50fa5a57ebb58876b71ec0b8b86c2f17aa7b25b9696dcb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(sequences, target):\n    return sorted(sequences,key=lambda s:abs(s-target))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([8, 9, 10, 11, 12], 10)),[10, 11, 9, 12, 8])\ncheck('fixture 2',solve(*([2, 0], 1)),[2, 0])\ncheck('fixture 3',solve(*([], 3)),[])\ncheck('fixture 4',solve(*([3], 3)),[3])\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":"4825ee1f110724e89cef66dc3470f04ac327f04433532ea073e2e155296b07df","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(sequences, target):\n    return sorted(sequences)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([8, 9, 10, 11, 12], 10)),[10, 11, 9, 12, 8])\ncheck('fixture 2',solve(*([2, 0], 1)),[2, 0])\ncheck('fixture 3',solve(*([], 3)),[])\ncheck('fixture 4',solve(*([3], 3)),[3])\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":"xmed-segment-priority-seek-distance","generated_at":"2026-09-29T14:38:45.645472+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic local media controller stage; metadata and downloaded data are supplied explicitly. No external player, service or codec is required.","root_cause":"Numeric download order fills old segments before the seek target.","sha256":"5bf04a2d9d5cc86ec0bdc0d5ec4e96208b632e6786df67a84fc57a3944029735","title":"Segment priority seek distance · case 01","variant":1,"variant_policy":"The five numbered cases rerun the same authored boundary fixtures; they are reproducibility runs, not independent input variants.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":36.716,"exit_code":1,"observations":[{"actual":[10,9,11,8,12],"check":"fixture 1","expected":[10,11,9,12,8],"passed":false},{"actual":[2,0],"check":"fixture 2","expected":[2,0],"passed":true},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[3],"check":"fixture 4","expected":[3],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [10, 9, 11, 8, 12], \"expected\": [10, 11, 9, 12, 8], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [2, 0], \"expected\": [2, 0], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [3], \"expected\": [3], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.354,"exit_code":1,"observations":[{"actual":[8,9,10,11,12],"check":"fixture 1","expected":[10,11,9,12,8],"passed":false},{"actual":[0,2],"check":"fixture 2","expected":[2,0],"passed":false},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[3],"check":"fixture 4","expected":[3],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [8, 9, 10, 11, 12], \"expected\": [10, 11, 9, 12, 8], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [0, 2], \"expected\": [2, 0], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [3], \"expected\": [3], \"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."}}