{"abstract":"A dangling PCM escape is falsely reported as a complete packet.","category":"PCM sample encoding","checks":8,"contract":"Decode a stipulated PCM residual stream with an escape token followed by an absolute sample anchor; report a dangling escape without losing valid prefix state.","evaluation_group":"s3-pcm-pcm-escaped-residuals","failed_approach":"Reporting seed rather than last reconstructed predictor loses valid prefix continuation.","family":"s3-pcm-pcm-escaped-residuals-truncated-escape","id":"FA-50126","implementations":{"attempt":{"sha256":"8cb9ce607b72f90b61244d75e305f9dd9d8df732c1fa001cdc67ab37c9d38215","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(tokens, initial, escape):\n    out=[]\n    previous=initial\n    cursor=0\n    while cursor<len(tokens):\n        token=tokens[cursor]\n        cursor+=1\n        if token==escape:\n            if cursor==len(tokens):\n                return [out,initial,'truncated']\n            previous=tokens[cursor]\n            cursor+=1\n        else:\n            previous+=token\n        out.append(previous)\n    return [out,previous,'ok']\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([1, 99, 20, -2], 10, 99)), [[11, 20, 18], 18, 'ok'])\ncheck('oracle 2', solve(*([99, -5, 2], 1, 99)), [[-5, -3], -3, 'ok'])\ncheck('oracle 3', solve(*([1, 99], 3, 99)), [[4], 4, 'truncated'])\ncheck('oracle 4', solve(*([], 4, 99)), [[], 4, 'ok'])\ncheck('oracle 5', solve(*([0, 1, 0], 2, 99)), [[2, 3, 3], 3, 'ok'])\ncheck('oracle 6', solve(*([8, 9, 0], 1, 7)), [[9, 18, 18], 18, 'ok'])\ncheck('oracle 7', solve(*([7, 3, 7, 8], 0, 7)), [[3, 8], 8, 'ok'])\nif N == 1: check('variant packet 1', solve(*[[1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 2: check('variant packet 2', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 3: check('variant packet 3', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 4: check('variant packet 4', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 5: check('variant packet 5', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\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":"b03d32785adac18ceb01b9b4e375f9bca5a33817259d027f964df2d9ad72e9a6","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(tokens, initial, escape):\n    out=[]\n    previous=initial\n    cursor=0\n    while cursor<len(tokens):\n        token=tokens[cursor]\n        cursor+=1\n        if token==escape:\n            if cursor==len(tokens):\n                return [out,previous,'ok']\n            previous=tokens[cursor]\n            cursor+=1\n        else:\n            previous+=token\n        out.append(previous)\n    return [out,previous,'ok']\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([1, 99, 20, -2], 10, 99)), [[11, 20, 18], 18, 'ok'])\ncheck('oracle 2', solve(*([99, -5, 2], 1, 99)), [[-5, -3], -3, 'ok'])\ncheck('oracle 3', solve(*([1, 99], 3, 99)), [[4], 4, 'truncated'])\ncheck('oracle 4', solve(*([], 4, 99)), [[], 4, 'ok'])\ncheck('oracle 5', solve(*([0, 1, 0], 2, 99)), [[2, 3, 3], 3, 'ok'])\ncheck('oracle 6', solve(*([8, 9, 0], 1, 7)), [[9, 18, 18], 18, 'ok'])\ncheck('oracle 7', solve(*([7, 3, 7, 8], 0, 7)), [[3, 8], 8, 'ok'])\nif N == 1: check('variant packet 1', solve(*[[1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 2: check('variant packet 2', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 3: check('variant packet 3', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 4: check('variant packet 4', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 5: check('variant packet 5', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\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":"8fb1ef408938fe1aaa436580f6ed38ab4209efae2a48f494c76437794a8db3ec","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(tokens, initial, escape):\n    out=[]\n    previous=initial\n    cursor=0\n    while cursor<len(tokens):\n        token=tokens[cursor]\n        cursor+=1\n        if token==escape:\n            if cursor==len(tokens):\n                return [out,previous,'truncated']\n            previous=tokens[cursor]\n            cursor+=1\n        else:\n            previous+=token\n        out.append(previous)\n    return [out,previous,'ok']\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('oracle 1', solve(*([1, 99, 20, -2], 10, 99)), [[11, 20, 18], 18, 'ok'])\ncheck('oracle 2', solve(*([99, -5, 2], 1, 99)), [[-5, -3], -3, 'ok'])\ncheck('oracle 3', solve(*([1, 99], 3, 99)), [[4], 4, 'truncated'])\ncheck('oracle 4', solve(*([], 4, 99)), [[], 4, 'ok'])\ncheck('oracle 5', solve(*([0, 1, 0], 2, 99)), [[2, 3, 3], 3, 'ok'])\ncheck('oracle 6', solve(*([8, 9, 0], 1, 7)), [[9, 18, 18], 18, 'ok'])\ncheck('oracle 7', solve(*([7, 3, 7, 8], 0, 7)), [[3, 8], 8, 'ok'])\nif N == 1: check('variant packet 1', solve(*[[1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 2: check('variant packet 2', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 3: check('variant packet 3', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 4: check('variant packet 4', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\nif N == 5: check('variant packet 5', solve(*[[1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2, 1, 99, 20, -2], 10, 99]), [[11, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18, 19, 20, 18], 18, 'ok'])\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":"Stipulated finite model; no claim of hardware timing or full file-format conformance. 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-pcm-pcm-escaped-residuals-truncated-escape","generated_at":"2026-09-29T14:45:06.250477+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Offline PCM interchange uses these exact bounded packet and sample representation decisions.","repair":"Use the stated conversion contract at truncated escape.","root_cause":"A dangling PCM escape is falsely reported as a complete packet.","sha256":"fb236dc6e46397ca105aad15d409ebd77bfca8e8e7eb6372c9887802e2e2da13","title":"Pcm escaped residuals: truncated escape · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":39.359,"exit_code":1,"observations":[{"actual":[[11,20,18],18,"ok"],"check":"oracle 1","expected":[[11,20,18],18,"ok"],"passed":true},{"actual":[[-5,-3],-3,"ok"],"check":"oracle 2","expected":[[-5,-3],-3,"ok"],"passed":true},{"actual":[[4],3,"truncated"],"check":"oracle 3","expected":[[4],4,"truncated"],"passed":false},{"actual":[[],4,"ok"],"check":"oracle 4","expected":[[],4,"ok"],"passed":true},{"actual":[[2,3,3],3,"ok"],"check":"oracle 5","expected":[[2,3,3],3,"ok"],"passed":true},{"actual":[[9,18,18],18,"ok"],"check":"oracle 6","expected":[[9,18,18],18,"ok"],"passed":true},{"actual":[[3,8],8,"ok"],"check":"oracle 7","expected":[[3,8],8,"ok"],"passed":true},{"actual":[[11,20,18,19,20,18],18,"ok"],"check":"variant packet 1","expected":[[11,20,18,19,20,18],18,"ok"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[11, 20, 18], 18, \"ok\"], \"expected\": [[11, 20, 18], 18, \"ok\"], \"passed\": true}, {\"check\": \"oracle 2\", \"actual\": [[-5, -3], -3, \"ok\"], \"expected\": [[-5, -3], -3, \"ok\"], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [[4], 3, \"truncated\"], \"expected\": [[4], 4, \"truncated\"], \"passed\": false}, {\"check\": \"oracle 4\", \"actual\": [[], 4, \"ok\"], \"expected\": [[], 4, \"ok\"], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[2, 3, 3], 3, \"ok\"], \"expected\": [[2, 3, 3], 3, \"ok\"], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [[9, 18, 18], 18, \"ok\"], \"expected\": [[9, 18, 18], 18, \"ok\"], \"passed\": true}, {\"check\": \"oracle 7\", \"actual\": [[3, 8], 8, \"ok\"], \"expected\": [[3, 8], 8, \"ok\"], \"passed\": true}, {\"check\": \"variant packet 1\", \"actual\": [[11, 20, 18, 19, 20, 18], 18, \"ok\"], \"expected\": [[11, 20, 18, 19, 20, 18], 18, \"ok\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.268,"exit_code":1,"observations":[{"actual":[[11,20,18],18,"ok"],"check":"oracle 1","expected":[[11,20,18],18,"ok"],"passed":true},{"actual":[[-5,-3],-3,"ok"],"check":"oracle 2","expected":[[-5,-3],-3,"ok"],"passed":true},{"actual":[[4],4,"ok"],"check":"oracle 3","expected":[[4],4,"truncated"],"passed":false},{"actual":[[],4,"ok"],"check":"oracle 4","expected":[[],4,"ok"],"passed":true},{"actual":[[2,3,3],3,"ok"],"check":"oracle 5","expected":[[2,3,3],3,"ok"],"passed":true},{"actual":[[9,18,18],18,"ok"],"check":"oracle 6","expected":[[9,18,18],18,"ok"],"passed":true},{"actual":[[3,8],8,"ok"],"check":"oracle 7","expected":[[3,8],8,"ok"],"passed":true},{"actual":[[11,20,18,19,20,18],18,"ok"],"check":"variant packet 1","expected":[[11,20,18,19,20,18],18,"ok"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[11, 20, 18], 18, \"ok\"], \"expected\": [[11, 20, 18], 18, \"ok\"], \"passed\": true}, {\"check\": \"oracle 2\", \"actual\": [[-5, -3], -3, \"ok\"], \"expected\": [[-5, -3], -3, \"ok\"], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [[4], 4, \"ok\"], \"expected\": [[4], 4, \"truncated\"], \"passed\": false}, {\"check\": \"oracle 4\", \"actual\": [[], 4, \"ok\"], \"expected\": [[], 4, \"ok\"], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[2, 3, 3], 3, \"ok\"], \"expected\": [[2, 3, 3], 3, \"ok\"], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [[9, 18, 18], 18, \"ok\"], \"expected\": [[9, 18, 18], 18, \"ok\"], \"passed\": true}, {\"check\": \"oracle 7\", \"actual\": [[3, 8], 8, \"ok\"], \"expected\": [[3, 8], 8, \"ok\"], \"passed\": true}, {\"check\": \"variant packet 1\", \"actual\": [[11, 20, 18, 19, 20, 18], 18, \"ok\"], \"expected\": [[11, 20, 18, 19, 20, 18], 18, \"ok\"], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.945,"exit_code":0,"observations":[{"actual":[[11,20,18],18,"ok"],"check":"oracle 1","expected":[[11,20,18],18,"ok"],"passed":true},{"actual":[[-5,-3],-3,"ok"],"check":"oracle 2","expected":[[-5,-3],-3,"ok"],"passed":true},{"actual":[[4],4,"truncated"],"check":"oracle 3","expected":[[4],4,"truncated"],"passed":true},{"actual":[[],4,"ok"],"check":"oracle 4","expected":[[],4,"ok"],"passed":true},{"actual":[[2,3,3],3,"ok"],"check":"oracle 5","expected":[[2,3,3],3,"ok"],"passed":true},{"actual":[[9,18,18],18,"ok"],"check":"oracle 6","expected":[[9,18,18],18,"ok"],"passed":true},{"actual":[[3,8],8,"ok"],"check":"oracle 7","expected":[[3,8],8,"ok"],"passed":true},{"actual":[[11,20,18,19,20,18],18,"ok"],"check":"variant packet 1","expected":[[11,20,18,19,20,18],18,"ok"],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"oracle 1\", \"actual\": [[11, 20, 18], 18, \"ok\"], \"expected\": [[11, 20, 18], 18, \"ok\"], \"passed\": true}, {\"check\": \"oracle 2\", \"actual\": [[-5, -3], -3, \"ok\"], \"expected\": [[-5, -3], -3, \"ok\"], \"passed\": true}, {\"check\": \"oracle 3\", \"actual\": [[4], 4, \"truncated\"], \"expected\": [[4], 4, \"truncated\"], \"passed\": true}, {\"check\": \"oracle 4\", \"actual\": [[], 4, \"ok\"], \"expected\": [[], 4, \"ok\"], \"passed\": true}, {\"check\": \"oracle 5\", \"actual\": [[2, 3, 3], 3, \"ok\"], \"expected\": [[2, 3, 3], 3, \"ok\"], \"passed\": true}, {\"check\": \"oracle 6\", \"actual\": [[9, 18, 18], 18, \"ok\"], \"expected\": [[9, 18, 18], 18, \"ok\"], \"passed\": true}, {\"check\": \"oracle 7\", \"actual\": [[3, 8], 8, \"ok\"], \"expected\": [[3, 8], 8, \"ok\"], \"passed\": true}, {\"check\": \"variant packet 1\", \"actual\": [[11, 20, 18, 19, 20, 18], 18, \"ok\"], \"expected\": [[11, 20, 18, 19, 20, 18], 18, \"ok\"], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}