{"abstract":"Lower-case suffixes such as \"df\" are rejected.","category":"Broadcast timecode arithmetic","checks":9,"contract":"Parse a rate descriptor: a known rate (23.976, 23.98, 24, 25, 29.97, 30, 50, 59.94, 60; redundant trailing decimal zeros allowed) with an optional case-insensitive DF/NDF suffix, optionally separated by a space or hyphen; surrounding whitespace ignored. Drop frame is only valid for 29.97 and 59.94. Return [num,den,drop] or None.","evaluation_group":"w2-broadcast-timecode-arithmetic-rate-descriptor","failed_approach":"Upper-casing without stripping leaves surrounding whitespace that defeats suffix matching.","family":"w2-broadcast-timecode-arithmetic-rate-descriptor-case-folding","id":"FA-78691","implementations":{"attempt":{"sha256":"168378ab03cea18bad17a88300ad606148facf96a2340286e0108aff10ca3db4","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    t=s.upper()\n    drop=t.endswith('DF') and not t.endswith('NDF')\n    base=t[:-3] if t.endswith('NDF') else t[:-2] if t.endswith('DF') else t\n    base=base.rstrip(' -')\n    if '.' in base:\n        base=base.rstrip('0').rstrip('.')\n    table={'23.976':(24000,1001),'23.98':(24000,1001),'24':(24,1),'25':(25,1),'29.97':(30000,1001),'30':(30,1),'50':(50,1),'59.94':(60000,1001),'60':(60,1)}\n    if base not in table:\n        return None\n    num,den=table[base]\n    if drop and den!=1001 or drop and num==24000:\n        return None\n    return [num,den,drop]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: case folding', ['59.94-df'], [60000, 1001, True]), ('regression variant: case folding', ['30.0 ndf'], [30, 1, False]), ('partial repair probe: case folding', [' 29.97 '], [30000, 1001, False]), ('partial repair variant: case folding', [' 29.970DF '], [30000, 1001, True]), ('boundary control', ['29.97DF'], [30000, 1001, True]), ('boundary control', ['23.976'], [24000, 1001, False]), ('normal control', ['29.97 NDF'], [30000, 1001, False]), ('normal control', ['30.0'], [30, 1, False]), ('normal control', [' 23.98df '], None)], [('regression: case folding', [' 30 ndf '], [30, 1, False]), ('regression variant: case folding', [' 29.97df '], [30000, 1001, True]), ('partial repair probe: case folding', [' 60 '], [60, 1, False]), ('partial repair variant: case folding', [' 59.94-DF '], [60000, 1001, True]), ('boundary control', ['29.97 NDF'], [30000, 1001, False]), ('boundary control', ['30.0'], [30, 1, False]), ('normal control', [' 25 DF '], None), ('normal control', ['30'], [30, 1, False]), ('normal control', ['31-DF'], None)], [('regression: case folding', ['50 ndf'], [50, 1, False]), ('regression variant: case folding', ['29.970df'], [30000, 1001, True]), ('partial repair probe: case folding', [' 23.98-NDF '], [24000, 1001, False]), ('partial repair variant: case folding', [' 59.94-DF '], [60000, 1001, True]), ('boundary control', ['30DF'], None), ('boundary control', ['29.97DF'], [30000, 1001, True]), ('normal control', [' 25DF '], None), ('normal control', ['25.00df'], None), ('normal control', [' 23.976 DF '], None)], [('regression: case folding', ['59.94 ndf'], [60000, 1001, False]), ('regression variant: case folding', ['24.0 ndf'], [24, 1, False]), ('partial repair probe: case folding', [' 29.97DF '], [30000, 1001, True]), ('partial repair variant: case folding', [' 29.970 DF '], [30000, 1001, True]), ('boundary control', ['23.976'], [24000, 1001, False]), ('boundary control', ['29.97 NDF'], [30000, 1001, False]), ('normal control', ['23.976DF'], None), ('normal control', ['24df'], None), ('normal control', ['24.0DF'], None)], [('regression: case folding', ['30 ndf'], [30, 1, False]), ('regression variant: case folding', [' 29.97 ndf '], [30000, 1001, False]), ('partial repair probe: case folding', [' 29.970 '], [30000, 1001, False]), ('partial repair variant: case folding', [' 60-NDF '], [60, 1, False]), ('boundary control', ['30.0'], [30, 1, False]), ('boundary control', ['30DF'], None), ('normal control', ['60NDF'], [60, 1, False]), ('normal control', ['29.97'], [30000, 1001, False]), ('normal control', ['29.97-NDF'], [30000, 1001, False])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"4e76a2217d1f0e846aa3de7b8146f292ea2d2742eff55419901f8a910eb53359","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    t=s.strip()\n    drop=t.endswith('DF') and not t.endswith('NDF')\n    base=t[:-3] if t.endswith('NDF') else t[:-2] if t.endswith('DF') else t\n    base=base.rstrip(' -')\n    if '.' in base:\n        base=base.rstrip('0').rstrip('.')\n    table={'23.976':(24000,1001),'23.98':(24000,1001),'24':(24,1),'25':(25,1),'29.97':(30000,1001),'30':(30,1),'50':(50,1),'59.94':(60000,1001),'60':(60,1)}\n    if base not in table:\n        return None\n    num,den=table[base]\n    if drop and den!=1001 or drop and num==24000:\n        return None\n    return [num,den,drop]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: case folding', ['59.94-df'], [60000, 1001, True]), ('regression variant: case folding', ['30.0 ndf'], [30, 1, False]), ('partial repair probe: case folding', [' 29.97 '], [30000, 1001, False]), ('partial repair variant: case folding', [' 29.970DF '], [30000, 1001, True]), ('boundary control', ['29.97DF'], [30000, 1001, True]), ('boundary control', ['23.976'], [24000, 1001, False]), ('normal control', ['29.97 NDF'], [30000, 1001, False]), ('normal control', ['30.0'], [30, 1, False]), ('normal control', [' 23.98df '], None)], [('regression: case folding', [' 30 ndf '], [30, 1, False]), ('regression variant: case folding', [' 29.97df '], [30000, 1001, True]), ('partial repair probe: case folding', [' 60 '], [60, 1, False]), ('partial repair variant: case folding', [' 59.94-DF '], [60000, 1001, True]), ('boundary control', ['29.97 NDF'], [30000, 1001, False]), ('boundary control', ['30.0'], [30, 1, False]), ('normal control', [' 25 DF '], None), ('normal control', ['30'], [30, 1, False]), ('normal control', ['31-DF'], None)], [('regression: case folding', ['50 ndf'], [50, 1, False]), ('regression variant: case folding', ['29.970df'], [30000, 1001, True]), ('partial repair probe: case folding', [' 23.98-NDF '], [24000, 1001, False]), ('partial repair variant: case folding', [' 59.94-DF '], [60000, 1001, True]), ('boundary control', ['30DF'], None), ('boundary control', ['29.97DF'], [30000, 1001, True]), ('normal control', [' 25DF '], None), ('normal control', ['25.00df'], None), ('normal control', [' 23.976 DF '], None)], [('regression: case folding', ['59.94 ndf'], [60000, 1001, False]), ('regression variant: case folding', ['24.0 ndf'], [24, 1, False]), ('partial repair probe: case folding', [' 29.97DF '], [30000, 1001, True]), ('partial repair variant: case folding', [' 29.970 DF '], [30000, 1001, True]), ('boundary control', ['23.976'], [24000, 1001, False]), ('boundary control', ['29.97 NDF'], [30000, 1001, False]), ('normal control', ['23.976DF'], None), ('normal control', ['24df'], None), ('normal control', ['24.0DF'], None)], [('regression: case folding', ['30 ndf'], [30, 1, False]), ('regression variant: case folding', [' 29.97 ndf '], [30000, 1001, False]), ('partial repair probe: case folding', [' 29.970 '], [30000, 1001, False]), ('partial repair variant: case folding', [' 60-NDF '], [60, 1, False]), ('boundary control', ['30.0'], [30, 1, False]), ('boundary control', ['30DF'], None), ('normal control', ['60NDF'], [60, 1, False]), ('normal control', ['29.97'], [30000, 1001, False]), ('normal control', ['29.97-NDF'], [30000, 1001, False])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"59736fd33cff50fcd16c0f6a068fc0ea1729216ba5a20ff74555d77df0571ffb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    t=s.strip().upper()\n    drop=t.endswith('DF') and not t.endswith('NDF')\n    base=t[:-3] if t.endswith('NDF') else t[:-2] if t.endswith('DF') else t\n    base=base.rstrip(' -')\n    if '.' in base:\n        base=base.rstrip('0').rstrip('.')\n    table={'23.976':(24000,1001),'23.98':(24000,1001),'24':(24,1),'25':(25,1),'29.97':(30000,1001),'30':(30,1),'50':(50,1),'59.94':(60000,1001),'60':(60,1)}\n    if base not in table:\n        return None\n    num,den=table[base]\n    if drop and den!=1001 or drop and num==24000:\n        return None\n    return [num,den,drop]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[('regression: case folding', ['59.94-df'], [60000, 1001, True]), ('regression variant: case folding', ['30.0 ndf'], [30, 1, False]), ('partial repair probe: case folding', [' 29.97 '], [30000, 1001, False]), ('partial repair variant: case folding', [' 29.970DF '], [30000, 1001, True]), ('boundary control', ['29.97DF'], [30000, 1001, True]), ('boundary control', ['23.976'], [24000, 1001, False]), ('normal control', ['29.97 NDF'], [30000, 1001, False]), ('normal control', ['30.0'], [30, 1, False]), ('normal control', [' 23.98df '], None)], [('regression: case folding', [' 30 ndf '], [30, 1, False]), ('regression variant: case folding', [' 29.97df '], [30000, 1001, True]), ('partial repair probe: case folding', [' 60 '], [60, 1, False]), ('partial repair variant: case folding', [' 59.94-DF '], [60000, 1001, True]), ('boundary control', ['29.97 NDF'], [30000, 1001, False]), ('boundary control', ['30.0'], [30, 1, False]), ('normal control', [' 25 DF '], None), ('normal control', ['30'], [30, 1, False]), ('normal control', ['31-DF'], None)], [('regression: case folding', ['50 ndf'], [50, 1, False]), ('regression variant: case folding', ['29.970df'], [30000, 1001, True]), ('partial repair probe: case folding', [' 23.98-NDF '], [24000, 1001, False]), ('partial repair variant: case folding', [' 59.94-DF '], [60000, 1001, True]), ('boundary control', ['30DF'], None), ('boundary control', ['29.97DF'], [30000, 1001, True]), ('normal control', [' 25DF '], None), ('normal control', ['25.00df'], None), ('normal control', [' 23.976 DF '], None)], [('regression: case folding', ['59.94 ndf'], [60000, 1001, False]), ('regression variant: case folding', ['24.0 ndf'], [24, 1, False]), ('partial repair probe: case folding', [' 29.97DF '], [30000, 1001, True]), ('partial repair variant: case folding', [' 29.970 DF '], [30000, 1001, True]), ('boundary control', ['23.976'], [24000, 1001, False]), ('boundary control', ['29.97 NDF'], [30000, 1001, False]), ('normal control', ['23.976DF'], None), ('normal control', ['24df'], None), ('normal control', ['24.0DF'], None)], [('regression: case folding', ['30 ndf'], [30, 1, False]), ('regression variant: case folding', [' 29.97 ndf '], [30000, 1001, False]), ('partial repair probe: case folding', [' 29.970 '], [30000, 1001, False]), ('partial repair variant: case folding', [' 60-NDF '], [60, 1, False]), ('boundary control', ['30.0'], [30, 1, False]), ('boundary control', ['30DF'], None), ('normal control', ['60NDF'], [60, 1, False]), ('normal control', ['29.97'], [30000, 1001, False]), ('normal control', ['29.97-NDF'], [30000, 1001, False])]]\nfor label, args, expected in fixtures[N-1]:\n    check(label, solve(*args), expected)\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":"A deterministic bounded teaching model with a stipulated toy contract; it does not claim conformance to SMPTE or any broadcast standard. 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":"w2-broadcast-timecode-arithmetic-rate-descriptor-case-folding","generated_at":"2026-09-29T14:49:37.726053+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Timecode arithmetic errors misplace edits, commercial breaks and captions against the broadcast clock.","repair":"Strip and upper-case the descriptor.","root_cause":"The descriptor is not upper-cased before suffix matching.","sha256":"b973248d1d2b29d0220513622823394ae18d12e992d93d329844e45c2dfc35f6","title":"Frame-rate descriptor parsing: case folding · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":38.899,"exit_code":1,"observations":[{"actual":[60000,1001,true],"check":"regression: case folding","expected":[60000,1001,true],"passed":true},{"actual":[30,1,false],"check":"regression variant: case folding","expected":[30,1,false],"passed":true},{"actual":null,"check":"partial repair probe: case folding","expected":[30000,1001,false],"passed":false},{"actual":null,"check":"partial repair variant: case folding","expected":[30000,1001,true],"passed":false},{"actual":[30000,1001,true],"check":"boundary control","expected":[30000,1001,true],"passed":true},{"actual":[24000,1001,false],"check":"boundary control","expected":[24000,1001,false],"passed":true},{"actual":[30000,1001,false],"check":"normal control","expected":[30000,1001,false],"passed":true},{"actual":[30,1,false],"check":"normal control","expected":[30,1,false],"passed":true},{"actual":null,"check":"normal control","expected":null,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: case folding\", \"actual\": [60000, 1001, true], \"expected\": [60000, 1001, true], \"passed\": true}, {\"check\": \"regression variant: case folding\", \"actual\": [30, 1, false], \"expected\": [30, 1, false], \"passed\": true}, {\"check\": \"partial repair probe: case folding\", \"actual\": null, \"expected\": [30000, 1001, false], \"passed\": false}, {\"check\": \"partial repair variant: case folding\", \"actual\": null, \"expected\": [30000, 1001, true], \"passed\": false}, {\"check\": \"boundary control\", \"actual\": [30000, 1001, true], \"expected\": [30000, 1001, true], \"passed\": true}, {\"check\": \"boundary control\", \"actual\": [24000, 1001, false], \"expected\": [24000, 1001, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [30000, 1001, false], \"expected\": [30000, 1001, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [30, 1, false], \"expected\": [30, 1, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": null, \"expected\": null, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.35,"exit_code":1,"observations":[{"actual":null,"check":"regression: case folding","expected":[60000,1001,true],"passed":false},{"actual":null,"check":"regression variant: case folding","expected":[30,1,false],"passed":false},{"actual":[30000,1001,false],"check":"partial repair probe: case folding","expected":[30000,1001,false],"passed":true},{"actual":[30000,1001,true],"check":"partial repair variant: case folding","expected":[30000,1001,true],"passed":true},{"actual":[30000,1001,true],"check":"boundary control","expected":[30000,1001,true],"passed":true},{"actual":[24000,1001,false],"check":"boundary control","expected":[24000,1001,false],"passed":true},{"actual":[30000,1001,false],"check":"normal control","expected":[30000,1001,false],"passed":true},{"actual":[30,1,false],"check":"normal control","expected":[30,1,false],"passed":true},{"actual":null,"check":"normal control","expected":null,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: case folding\", \"actual\": null, \"expected\": [60000, 1001, true], \"passed\": false}, {\"check\": \"regression variant: case folding\", \"actual\": null, \"expected\": [30, 1, false], \"passed\": false}, {\"check\": \"partial repair probe: case folding\", \"actual\": [30000, 1001, false], \"expected\": [30000, 1001, false], \"passed\": true}, {\"check\": \"partial repair variant: case folding\", \"actual\": [30000, 1001, true], \"expected\": [30000, 1001, true], \"passed\": true}, {\"check\": \"boundary control\", \"actual\": [30000, 1001, true], \"expected\": [30000, 1001, true], \"passed\": true}, {\"check\": \"boundary control\", \"actual\": [24000, 1001, false], \"expected\": [24000, 1001, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [30000, 1001, false], \"expected\": [30000, 1001, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [30, 1, false], \"expected\": [30, 1, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": null, \"expected\": null, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":42.287,"exit_code":0,"observations":[{"actual":[60000,1001,true],"check":"regression: case folding","expected":[60000,1001,true],"passed":true},{"actual":[30,1,false],"check":"regression variant: case folding","expected":[30,1,false],"passed":true},{"actual":[30000,1001,false],"check":"partial repair probe: case folding","expected":[30000,1001,false],"passed":true},{"actual":[30000,1001,true],"check":"partial repair variant: case folding","expected":[30000,1001,true],"passed":true},{"actual":[30000,1001,true],"check":"boundary control","expected":[30000,1001,true],"passed":true},{"actual":[24000,1001,false],"check":"boundary control","expected":[24000,1001,false],"passed":true},{"actual":[30000,1001,false],"check":"normal control","expected":[30000,1001,false],"passed":true},{"actual":[30,1,false],"check":"normal control","expected":[30,1,false],"passed":true},{"actual":null,"check":"normal control","expected":null,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: case folding\", \"actual\": [60000, 1001, true], \"expected\": [60000, 1001, true], \"passed\": true}, {\"check\": \"regression variant: case folding\", \"actual\": [30, 1, false], \"expected\": [30, 1, false], \"passed\": true}, {\"check\": \"partial repair probe: case folding\", \"actual\": [30000, 1001, false], \"expected\": [30000, 1001, false], \"passed\": true}, {\"check\": \"partial repair variant: case folding\", \"actual\": [30000, 1001, true], \"expected\": [30000, 1001, true], \"passed\": true}, {\"check\": \"boundary control\", \"actual\": [30000, 1001, true], \"expected\": [30000, 1001, true], \"passed\": true}, {\"check\": \"boundary control\", \"actual\": [24000, 1001, false], \"expected\": [24000, 1001, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [30000, 1001, false], \"expected\": [30000, 1001, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": [30, 1, false], \"expected\": [30, 1, false], \"passed\": true}, {\"check\": \"normal control\", \"actual\": null, \"expected\": null, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}