{"abstract":"Removing a track occurrence deletes every playlist occurrence of that track.","category":"Media playlist state","checks":4,"contract":"Entries are [unique entry-ID,track-ID]. Remove exactly the selected entry identity, retaining other appearances of the same track.","evaluation_group":"xmed-duplicate-track-removal-by-entry-id","failed_approach":"Keeping only the targeted identity reverses the removal predicate.","family":"xmed-duplicate-track-removal-by-entry-id","id":"FA-11051","implementations":{"attempt":{"sha256":"6caa4d57a79a7cf4e54aae63e36ff053fb17d28420760a0c648df4c05df7137e","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(entries, identity):\n    return [x for x in entries if x[0]==identity]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([['e1', 'song'], ['e2', 'song'], ['e3', 'other']], 'e1')),[['e2', 'song'], ['e3', 'other']])\ncheck('fixture 2',solve(*([], 'x')),[])\ncheck('fixture 3',solve(*([['a', 'song']], 'x')),[['a', 'song']])\ncheck('fixture 4',solve(*([['a', 'song']], '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":"f34a471dbf507cdd2f0fa957f2539d343a2079372e1156a80346702bb18bbef7","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(entries, identity):\n    return [x for x in entries if x[1]!=next((y[1] for y in entries if y[0]==identity),None)]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([['e1', 'song'], ['e2', 'song'], ['e3', 'other']], 'e1')),[['e2', 'song'], ['e3', 'other']])\ncheck('fixture 2',solve(*([], 'x')),[])\ncheck('fixture 3',solve(*([['a', 'song']], 'x')),[['a', 'song']])\ncheck('fixture 4',solve(*([['a', 'song']], '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"},"fixed":{"sha256":"066fa82747565db9a29d90b0efc8ddf79d3ca2704d10e9c1896310d791d1e3f8","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(entries, identity):\n    return [x for x in entries if x[0]!=identity]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1',solve(*([['e1', 'song'], ['e2', 'song'], ['e3', 'other']], 'e1')),[['e2', 'song'], ['e3', 'other']])\ncheck('fixture 2',solve(*([], 'x')),[])\ncheck('fixture 3',solve(*([['a', 'song']], 'x')),[['a', 'song']])\ncheck('fixture 4',solve(*([['a', 'song']], '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-duplicate-track-removal-by-entry-id","generated_at":"2026-09-29T14:38:44.468133+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.","repair":"Preserve the media contract: Entries are [unique entry-ID,track-ID]. Remove exactly the selected entry identity, retaining other appearances of the same track.","root_cause":"Removing a track occurrence deletes every playlist occurrence of that track.","sha256":"1756e35fe3a6eabca7bc5376f806cb3e61b86fa1be486bf58f0b727cc1296f63","title":"Duplicate track removal by entry id · case 01","variant":1,"variant_policy":"The five numbered cases rerun the same authored boundary fixtures; they are reproducibility runs, not independent input variants.","verification":{"attempt":{"elapsed_ms":37.98,"exit_code":1,"observations":[{"actual":[["e1","song"]],"check":"fixture 1","expected":[["e2","song"],["e3","other"]],"passed":false},{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":[],"check":"fixture 3","expected":[["a","song"]],"passed":false},{"actual":[["a","song"]],"check":"fixture 4","expected":[],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[\"e1\", \"song\"]], \"expected\": [[\"e2\", \"song\"], [\"e3\", \"other\"]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [[\"a\", \"song\"]], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [[\"a\", \"song\"]], \"expected\": [], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.619,"exit_code":1,"observations":[{"actual":[["e3","other"]],"check":"fixture 1","expected":[["e2","song"],["e3","other"]],"passed":false},{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":[["a","song"]],"check":"fixture 3","expected":[["a","song"]],"passed":true},{"actual":[],"check":"fixture 4","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[\"e3\", \"other\"]], \"expected\": [[\"e2\", \"song\"], [\"e3\", \"other\"]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [[\"a\", \"song\"]], \"expected\": [[\"a\", \"song\"]], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":40.441,"exit_code":0,"observations":[{"actual":[["e2","song"],["e3","other"]],"check":"fixture 1","expected":[["e2","song"],["e3","other"]],"passed":true},{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":[["a","song"]],"check":"fixture 3","expected":[["a","song"]],"passed":true},{"actual":[],"check":"fixture 4","expected":[],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[\"e2\", \"song\"], [\"e3\", \"other\"]], \"expected\": [[\"e2\", \"song\"], [\"e3\", \"other\"]], \"passed\": true}, {\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [[\"a\", \"song\"]], \"expected\": [[\"a\", \"song\"]], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}