{"abstract":"Decoded run values use a logical-row address.","category":"Data systems","checks":7,"contract":"Decode a run-end vector into the requested [start,start+length) slice. Run ends are exclusive cumulative positions; values and validity are stored per run. Empty slices return empty.","evaluation_group":"s3-data-systems-run-end-slice","failed_approach":"Rebasing to the slice start still confuses row and run coordinates.","family":"s3-data-systems-run-end-slice-run-value","id":"FA-44411","implementations":{"attempt":{"sha256":"b4b2b85b25dd4d3a3e82568088af766ba9dc76020f24920278b6fbde3012887c","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(d):\n    try:\n        ends,values,valid,start,length=d\n        out=[]\n        for pos in range(start,start+length):\n            r=next(i for i,end in enumerate(ends) if pos < end)\n            value=values[min(pos-start,len(values)-1)]\n            known=valid[r]\n            out.append(value if known else None)\n        return out\n    except (IndexError, KeyError, ValueError, StopIteration) as exc:\n        return {\"representation_error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nif N == 1:\n    check('crossing run boundary', solve([[2, 5], [1, 2], [True, True], 1, 3]), [1, 2, 2])\n    check('start at boundary', solve([[2, 5], [1, 2], [True, True], 2, 2]), [2, 2])\n    check('null middle run', solve([[1, 3, 5], [1, 2, 3], [True, False, True], 0, 5]), [1, None, None, 3, 3])\n    check('null first run', solve([[1, 3], [1, 2], [False, True], 1, 2]), [2, 2])\n    check('empty slice', solve([[3], [1], [True], 1, 0]), [])\n    check('single run', solve([[4], [1], [True], 0, 4]), [1, 1, 1, 1])\n    check('tail slice', solve([[1, 2, 6], [1, 2, 3], [True, True, True], 4, 2]), [3, 3])\nelif N == 2:\n    check('crossing run boundary', solve([[2, 5], [2, 3], [True, True], 1, 3]), [2, 3, 3])\n    check('start at boundary', solve([[2, 5], [2, 3], [True, True], 2, 2]), [3, 3])\n    check('null middle run', solve([[1, 3, 5], [2, 3, 4], [True, False, True], 0, 5]), [2, None, None, 4, 4])\n    check('null first run', solve([[1, 3], [2, 3], [False, True], 1, 2]), [3, 3])\n    check('empty slice', solve([[3], [2], [True], 1, 0]), [])\n    check('single run', solve([[4], [2], [True], 0, 4]), [2, 2, 2, 2])\n    check('tail slice', solve([[1, 2, 6], [2, 3, 4], [True, True, True], 4, 2]), [4, 4])\nelif N == 3:\n    check('crossing run boundary', solve([[2, 5], [3, 4], [True, True], 1, 3]), [3, 4, 4])\n    check('start at boundary', solve([[2, 5], [3, 4], [True, True], 2, 2]), [4, 4])\n    check('null middle run', solve([[1, 3, 5], [3, 4, 5], [True, False, True], 0, 5]), [3, None, None, 5, 5])\n    check('null first run', solve([[1, 3], [3, 4], [False, True], 1, 2]), [4, 4])\n    check('empty slice', solve([[3], [3], [True], 1, 0]), [])\n    check('single run', solve([[4], [3], [True], 0, 4]), [3, 3, 3, 3])\n    check('tail slice', solve([[1, 2, 6], [3, 4, 5], [True, True, True], 4, 2]), [5, 5])\nelif N == 4:\n    check('crossing run boundary', solve([[2, 5], [4, 5], [True, True], 1, 3]), [4, 5, 5])\n    check('start at boundary', solve([[2, 5], [4, 5], [True, True], 2, 2]), [5, 5])\n    check('null middle run', solve([[1, 3, 5], [4, 5, 6], [True, False, True], 0, 5]), [4, None, None, 6, 6])\n    check('null first run', solve([[1, 3], [4, 5], [False, True], 1, 2]), [5, 5])\n    check('empty slice', solve([[3], [4], [True], 1, 0]), [])\n    check('single run', solve([[4], [4], [True], 0, 4]), [4, 4, 4, 4])\n    check('tail slice', solve([[1, 2, 6], [4, 5, 6], [True, True, True], 4, 2]), [6, 6])\nelif N == 5:\n    check('crossing run boundary', solve([[2, 5], [5, 6], [True, True], 1, 3]), [5, 6, 6])\n    check('start at boundary', solve([[2, 5], [5, 6], [True, True], 2, 2]), [6, 6])\n    check('null middle run', solve([[1, 3, 5], [5, 6, 7], [True, False, True], 0, 5]), [5, None, None, 7, 7])\n    check('null first run', solve([[1, 3], [5, 6], [False, True], 1, 2]), [6, 6])\n    check('empty slice', solve([[3], [5], [True], 1, 0]), [])\n    check('single run', solve([[4], [5], [True], 0, 4]), [5, 5, 5, 5])\n    check('tail slice', solve([[1, 2, 6], [5, 6, 7], [True, True, True], 4, 2]), [7, 7])\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":"8dccc9da7c0eefbf9a40f4fe49c9c316d220da3c5fcabe7dfb1b3448d0efdeec","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(d):\n    try:\n        ends,values,valid,start,length=d\n        out=[]\n        for pos in range(start,start+length):\n            r=next(i for i,end in enumerate(ends) if pos < end)\n            value=values[min(pos,len(values)-1)]\n            known=valid[r]\n            out.append(value if known else None)\n        return out\n    except (IndexError, KeyError, ValueError, StopIteration) as exc:\n        return {\"representation_error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nif N == 1:\n    check('crossing run boundary', solve([[2, 5], [1, 2], [True, True], 1, 3]), [1, 2, 2])\n    check('start at boundary', solve([[2, 5], [1, 2], [True, True], 2, 2]), [2, 2])\n    check('null middle run', solve([[1, 3, 5], [1, 2, 3], [True, False, True], 0, 5]), [1, None, None, 3, 3])\n    check('null first run', solve([[1, 3], [1, 2], [False, True], 1, 2]), [2, 2])\n    check('empty slice', solve([[3], [1], [True], 1, 0]), [])\n    check('single run', solve([[4], [1], [True], 0, 4]), [1, 1, 1, 1])\n    check('tail slice', solve([[1, 2, 6], [1, 2, 3], [True, True, True], 4, 2]), [3, 3])\nelif N == 2:\n    check('crossing run boundary', solve([[2, 5], [2, 3], [True, True], 1, 3]), [2, 3, 3])\n    check('start at boundary', solve([[2, 5], [2, 3], [True, True], 2, 2]), [3, 3])\n    check('null middle run', solve([[1, 3, 5], [2, 3, 4], [True, False, True], 0, 5]), [2, None, None, 4, 4])\n    check('null first run', solve([[1, 3], [2, 3], [False, True], 1, 2]), [3, 3])\n    check('empty slice', solve([[3], [2], [True], 1, 0]), [])\n    check('single run', solve([[4], [2], [True], 0, 4]), [2, 2, 2, 2])\n    check('tail slice', solve([[1, 2, 6], [2, 3, 4], [True, True, True], 4, 2]), [4, 4])\nelif N == 3:\n    check('crossing run boundary', solve([[2, 5], [3, 4], [True, True], 1, 3]), [3, 4, 4])\n    check('start at boundary', solve([[2, 5], [3, 4], [True, True], 2, 2]), [4, 4])\n    check('null middle run', solve([[1, 3, 5], [3, 4, 5], [True, False, True], 0, 5]), [3, None, None, 5, 5])\n    check('null first run', solve([[1, 3], [3, 4], [False, True], 1, 2]), [4, 4])\n    check('empty slice', solve([[3], [3], [True], 1, 0]), [])\n    check('single run', solve([[4], [3], [True], 0, 4]), [3, 3, 3, 3])\n    check('tail slice', solve([[1, 2, 6], [3, 4, 5], [True, True, True], 4, 2]), [5, 5])\nelif N == 4:\n    check('crossing run boundary', solve([[2, 5], [4, 5], [True, True], 1, 3]), [4, 5, 5])\n    check('start at boundary', solve([[2, 5], [4, 5], [True, True], 2, 2]), [5, 5])\n    check('null middle run', solve([[1, 3, 5], [4, 5, 6], [True, False, True], 0, 5]), [4, None, None, 6, 6])\n    check('null first run', solve([[1, 3], [4, 5], [False, True], 1, 2]), [5, 5])\n    check('empty slice', solve([[3], [4], [True], 1, 0]), [])\n    check('single run', solve([[4], [4], [True], 0, 4]), [4, 4, 4, 4])\n    check('tail slice', solve([[1, 2, 6], [4, 5, 6], [True, True, True], 4, 2]), [6, 6])\nelif N == 5:\n    check('crossing run boundary', solve([[2, 5], [5, 6], [True, True], 1, 3]), [5, 6, 6])\n    check('start at boundary', solve([[2, 5], [5, 6], [True, True], 2, 2]), [6, 6])\n    check('null middle run', solve([[1, 3, 5], [5, 6, 7], [True, False, True], 0, 5]), [5, None, None, 7, 7])\n    check('null first run', solve([[1, 3], [5, 6], [False, True], 1, 2]), [6, 6])\n    check('empty slice', solve([[3], [5], [True], 1, 0]), [])\n    check('single run', solve([[4], [5], [True], 0, 4]), [5, 5, 5, 5])\n    check('tail slice', solve([[1, 2, 6], [5, 6, 7], [True, True, True], 4, 2]), [7, 7])\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":"cceab14c6e91b208254b8b93e701952d04ff5cbc675816011cb2dd9c3f8da4b1","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(d):\n    try:\n        ends,values,valid,start,length=d\n        out=[]\n        for pos in range(start,start+length):\n            r=next(i for i,end in enumerate(ends) if pos < end)\n            value=values[r]\n            known=valid[r]\n            out.append(value if known else None)\n        return out\n    except (IndexError, KeyError, ValueError, StopIteration) as exc:\n        return {\"representation_error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nif N == 1:\n    check('crossing run boundary', solve([[2, 5], [1, 2], [True, True], 1, 3]), [1, 2, 2])\n    check('start at boundary', solve([[2, 5], [1, 2], [True, True], 2, 2]), [2, 2])\n    check('null middle run', solve([[1, 3, 5], [1, 2, 3], [True, False, True], 0, 5]), [1, None, None, 3, 3])\n    check('null first run', solve([[1, 3], [1, 2], [False, True], 1, 2]), [2, 2])\n    check('empty slice', solve([[3], [1], [True], 1, 0]), [])\n    check('single run', solve([[4], [1], [True], 0, 4]), [1, 1, 1, 1])\n    check('tail slice', solve([[1, 2, 6], [1, 2, 3], [True, True, True], 4, 2]), [3, 3])\nelif N == 2:\n    check('crossing run boundary', solve([[2, 5], [2, 3], [True, True], 1, 3]), [2, 3, 3])\n    check('start at boundary', solve([[2, 5], [2, 3], [True, True], 2, 2]), [3, 3])\n    check('null middle run', solve([[1, 3, 5], [2, 3, 4], [True, False, True], 0, 5]), [2, None, None, 4, 4])\n    check('null first run', solve([[1, 3], [2, 3], [False, True], 1, 2]), [3, 3])\n    check('empty slice', solve([[3], [2], [True], 1, 0]), [])\n    check('single run', solve([[4], [2], [True], 0, 4]), [2, 2, 2, 2])\n    check('tail slice', solve([[1, 2, 6], [2, 3, 4], [True, True, True], 4, 2]), [4, 4])\nelif N == 3:\n    check('crossing run boundary', solve([[2, 5], [3, 4], [True, True], 1, 3]), [3, 4, 4])\n    check('start at boundary', solve([[2, 5], [3, 4], [True, True], 2, 2]), [4, 4])\n    check('null middle run', solve([[1, 3, 5], [3, 4, 5], [True, False, True], 0, 5]), [3, None, None, 5, 5])\n    check('null first run', solve([[1, 3], [3, 4], [False, True], 1, 2]), [4, 4])\n    check('empty slice', solve([[3], [3], [True], 1, 0]), [])\n    check('single run', solve([[4], [3], [True], 0, 4]), [3, 3, 3, 3])\n    check('tail slice', solve([[1, 2, 6], [3, 4, 5], [True, True, True], 4, 2]), [5, 5])\nelif N == 4:\n    check('crossing run boundary', solve([[2, 5], [4, 5], [True, True], 1, 3]), [4, 5, 5])\n    check('start at boundary', solve([[2, 5], [4, 5], [True, True], 2, 2]), [5, 5])\n    check('null middle run', solve([[1, 3, 5], [4, 5, 6], [True, False, True], 0, 5]), [4, None, None, 6, 6])\n    check('null first run', solve([[1, 3], [4, 5], [False, True], 1, 2]), [5, 5])\n    check('empty slice', solve([[3], [4], [True], 1, 0]), [])\n    check('single run', solve([[4], [4], [True], 0, 4]), [4, 4, 4, 4])\n    check('tail slice', solve([[1, 2, 6], [4, 5, 6], [True, True, True], 4, 2]), [6, 6])\nelif N == 5:\n    check('crossing run boundary', solve([[2, 5], [5, 6], [True, True], 1, 3]), [5, 6, 6])\n    check('start at boundary', solve([[2, 5], [5, 6], [True, True], 2, 2]), [6, 6])\n    check('null middle run', solve([[1, 3, 5], [5, 6, 7], [True, False, True], 0, 5]), [5, None, None, 7, 7])\n    check('null first run', solve([[1, 3], [5, 6], [False, True], 1, 2]), [6, 6])\n    check('empty slice', solve([[3], [5], [True], 1, 0]), [])\n    check('single run', solve([[4], [5], [True], 0, 4]), [5, 5, 5, 5])\n    check('tail slice', solve([[1, 2, 6], [5, 6, 7], [True, True, True], 4, 2]), [7, 7])\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":"Offline stipulated semantics over valid small inputs; no performance, concurrency, or production-engine conformance claim. 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-data-systems-run-end-slice-run-value","generated_at":"2026-09-29T14:44:11.972498+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A bounded deterministic data engine model makes representation and changelog faults reproducible.","repair":"Preserve the stated physical representation and operation order: Decode a run-end vector into the requested [start,start+length) slice. Run ends are exclusive cumulative positions; values and validity are stored per run. Empty slices return empty.","root_cause":"run-end-slice: Decoded run values use a logical-row address.","sha256":"2390b6554e1b30181edc37c0cfcd31775bf5647cc8c0bd1491589feb7d4e1cb5","title":"Decoded run values use a logical-row address · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":43.343,"exit_code":1,"observations":[{"actual":[1,2,2],"check":"crossing run boundary","expected":[1,2,2],"passed":true},{"actual":[1,2],"check":"start at boundary","expected":[2,2],"passed":false},{"actual":[1,null,null,3,3],"check":"null middle run","expected":[1,null,null,3,3],"passed":true},{"actual":[1,2],"check":"null first run","expected":[2,2],"passed":false},{"actual":[],"check":"empty slice","expected":[],"passed":true},{"actual":[1,1,1,1],"check":"single run","expected":[1,1,1,1],"passed":true},{"actual":[1,2],"check":"tail slice","expected":[3,3],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"crossing run boundary\", \"actual\": [1, 2, 2], \"expected\": [1, 2, 2], \"passed\": true}, {\"check\": \"start at boundary\", \"actual\": [1, 2], \"expected\": [2, 2], \"passed\": false}, {\"check\": \"null middle run\", \"actual\": [1, null, null, 3, 3], \"expected\": [1, null, null, 3, 3], \"passed\": true}, {\"check\": \"null first run\", \"actual\": [1, 2], \"expected\": [2, 2], \"passed\": false}, {\"check\": \"empty slice\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"single run\", \"actual\": [1, 1, 1, 1], \"expected\": [1, 1, 1, 1], \"passed\": true}, {\"check\": \"tail slice\", \"actual\": [1, 2], \"expected\": [3, 3], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":43.579,"exit_code":1,"observations":[{"actual":[2,2,2],"check":"crossing run boundary","expected":[1,2,2],"passed":false},{"actual":[2,2],"check":"start at boundary","expected":[2,2],"passed":true},{"actual":[1,null,null,3,3],"check":"null middle run","expected":[1,null,null,3,3],"passed":true},{"actual":[2,2],"check":"null first run","expected":[2,2],"passed":true},{"actual":[],"check":"empty slice","expected":[],"passed":true},{"actual":[1,1,1,1],"check":"single run","expected":[1,1,1,1],"passed":true},{"actual":[3,3],"check":"tail slice","expected":[3,3],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"crossing run boundary\", \"actual\": [2, 2, 2], \"expected\": [1, 2, 2], \"passed\": false}, {\"check\": \"start at boundary\", \"actual\": [2, 2], \"expected\": [2, 2], \"passed\": true}, {\"check\": \"null middle run\", \"actual\": [1, null, null, 3, 3], \"expected\": [1, null, null, 3, 3], \"passed\": true}, {\"check\": \"null first run\", \"actual\": [2, 2], \"expected\": [2, 2], \"passed\": true}, {\"check\": \"empty slice\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"single run\", \"actual\": [1, 1, 1, 1], \"expected\": [1, 1, 1, 1], \"passed\": true}, {\"check\": \"tail slice\", \"actual\": [3, 3], \"expected\": [3, 3], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":43.438,"exit_code":0,"observations":[{"actual":[1,2,2],"check":"crossing run boundary","expected":[1,2,2],"passed":true},{"actual":[2,2],"check":"start at boundary","expected":[2,2],"passed":true},{"actual":[1,null,null,3,3],"check":"null middle run","expected":[1,null,null,3,3],"passed":true},{"actual":[2,2],"check":"null first run","expected":[2,2],"passed":true},{"actual":[],"check":"empty slice","expected":[],"passed":true},{"actual":[1,1,1,1],"check":"single run","expected":[1,1,1,1],"passed":true},{"actual":[3,3],"check":"tail slice","expected":[3,3],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"crossing run boundary\", \"actual\": [1, 2, 2], \"expected\": [1, 2, 2], \"passed\": true}, {\"check\": \"start at boundary\", \"actual\": [2, 2], \"expected\": [2, 2], \"passed\": true}, {\"check\": \"null middle run\", \"actual\": [1, null, null, 3, 3], \"expected\": [1, null, null, 3, 3], \"passed\": true}, {\"check\": \"null first run\", \"actual\": [2, 2], \"expected\": [2, 2], \"passed\": true}, {\"check\": \"empty slice\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"single run\", \"actual\": [1, 1, 1, 1], \"expected\": [1, 1, 1, 1], \"passed\": true}, {\"check\": \"tail slice\", \"actual\": [3, 3], \"expected\": [3, 3], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}