{"abstract":"A declared missing segment is repeatedly downloaded instead of represented as a playback gap.","category":"Streaming segment lifecycle","checks":4,"contract":"Convert manifest [segment-ID,gap flag] entries to required downloads; explicitly missing gap segments are skipped without suppressing neighboring media.","contract_signature":"segments","evaluation_group":"xmed-segment-explicit-gap-skips-download","failed_approach":"Keeping only gaps reverses the available-segment selection.","family":"xmed-segment-explicit-gap-skips-download","id":"FA-11201","implementations":{"attempt":{"sha256":"909ec17f3c65bcedad116cac6fa1d8aa34ea3fd3d9af8f78f1196777c4138028","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(segments):\n    return [identity for identity,gap in segments if gap]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([['a', False], ['b', True], ['c', False]],)),['a', 'c'])\ncheck('fixture 2',solve(*([['a', True]],)),[])\ncheck('fixture 3',solve(*([],)),[])\ncheck('fixture 4',solve(*([['a', False]],)),['a'])\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":"4ea197e76a4557bd9a5d05a76102b2208974ec4854ba08aca853da1215f9555a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(segments):\n    return [identity for identity,gap in segments]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([['a', False], ['b', True], ['c', False]],)),['a', 'c'])\ncheck('fixture 2',solve(*([['a', True]],)),[])\ncheck('fixture 3',solve(*([],)),[])\ncheck('fixture 4',solve(*([['a', False]],)),['a'])\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-explicit-gap-skips-download","generated_at":"2026-09-29T14:38:45.855214+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":"A declared missing segment is repeatedly downloaded instead of represented as a playback gap.","sha256":"a6dfbf2df214e2263dcde6ad10ed50e82ba1f2b14c5777a8115122b2c5ea6242","title":"Segment explicit gap skips download · 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":39.933,"exit_code":1,"observations":[{"actual":["b"],"check":"fixture 1","expected":["a","c"],"passed":false},{"actual":["a"],"check":"fixture 2","expected":[],"passed":false},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":[],"check":"fixture 4","expected":["a"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [\"b\"], \"expected\": [\"a\", \"c\"], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [\"a\"], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [\"a\"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.366,"exit_code":1,"observations":[{"actual":["a","b","c"],"check":"fixture 1","expected":["a","c"],"passed":false},{"actual":["a"],"check":"fixture 2","expected":[],"passed":false},{"actual":[],"check":"fixture 3","expected":[],"passed":true},{"actual":["a"],"check":"fixture 4","expected":["a"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [\"a\", \"b\", \"c\"], \"expected\": [\"a\", \"c\"], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [\"a\"], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [\"a\"], \"expected\": [\"a\"], \"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."}}