{"abstract":"A cell is placed into a column occupied by a previous row span in the controlled document model.","category":"Document structure integrity","checks":6,"contract":"Rows contain positive row-span lengths for unit-width cells. Place each row cell into the first free column at or after the preceding cell; previous spans occupy their columns for exactly their span rows.","evaluation_group":"model-7f226d1edd6c026e","failed_approach":"Remembering occupied columns forever prevents reuse after a row span expires.","family":"z-documents-table-rowspan-placement","id":"FA-11836","implementations":{"attempt":{"sha256":"4ffcc0bde17835993e46fc7c952b53ab66aeeb46a46d52fe83098720ae672fa9","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    out=[]\n    occupied=set()\n    for row in rows:\n        positions=[]\n        col=0\n        for span in row:\n            while col in occupied: col+=1\n            positions.append(col)\n            if span>1: occupied.add(col)\n            col+=1\n        out.append(positions)\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [(([[2],[1],[N]],),[[0],[1],[0]]), (([],),[]), (([[]],),[[]]), (([[1,1],[1]],),[[0,1],[0]]), (([[3],[2],[1],[1]],),[[0],[1],[2],[0]]), (([[2,1],[],[1]],),[[0,1],[],[0]])]\nfor i, (args, expected) in enumerate(fixtures):\n    check(\"document fixture \" + str(i), 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":"d748076570aa957809c55137735feef93521ba857b33b5f31a7b6e3608370d71","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    return [list(range(len(row))) for row in rows]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [(([[2],[1],[N]],),[[0],[1],[0]]), (([],),[]), (([[]],),[[]]), (([[1,1],[1]],),[[0,1],[0]]), (([[3],[2],[1],[1]],),[[0],[1],[2],[0]]), (([[2,1],[],[1]],),[[0,1],[],[0]])]\nfor i, (args, expected) in enumerate(fixtures):\n    check(\"document fixture \" + str(i), 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":"4fb8e50b2bad877ddacf7553e09f46b860459c46fe4cfc6253884d77ba90ad8f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(rows):\n    out=[]\n    ends={}\n    for r,row in enumerate(rows):\n        positions=[]\n        col=0\n        for span in row:\n            while ends.get(col,0)>r: col+=1\n            positions.append(col)\n            ends[col]=r+span\n            col+=1\n        out.append(positions)\n    return out\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [(([[2],[1],[N]],),[[0],[1],[0]]), (([],),[]), (([[]],),[[]]), (([[1,1],[1]],),[[0,1],[0]]), (([[3],[2],[1],[1]],),[[0],[1],[2],[0]]), (([[2,1],[],[1]],),[[0,1],[],[0]])]\nfor i, (args, expected) in enumerate(fixtures):\n    check(\"document fixture \" + str(i), 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":"An offline simplified document model, not a claim of conformance to any office file format. 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":"z-documents-table-rowspan-placement","generated_at":"2026-09-29T14:38:51.473055+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Structured editing must preserve document semantics independently of visual rendering.","repair":"Track the exclusive ending row of each occupied column and release it at that boundary.","root_cause":"Logical row cells are numbered without consulting vertical merge occupancy.","sha256":"43db8698774be24fc9e70b411a25de743d7f82dffc98255e0718f9e80d0648b2","title":"A cell is placed into a column occupied by a previous row span · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":39.969,"exit_code":1,"observations":[{"actual":[[0],[1],[1]],"check":"document fixture 0","expected":[[0],[1],[0]],"passed":false},{"actual":[],"check":"document fixture 1","expected":[],"passed":true},{"actual":[[]],"check":"document fixture 2","expected":[[]],"passed":true},{"actual":[[0,1],[0]],"check":"document fixture 3","expected":[[0,1],[0]],"passed":true},{"actual":[[0],[1],[2],[2]],"check":"document fixture 4","expected":[[0],[1],[2],[0]],"passed":false},{"actual":[[0,1],[],[1]],"check":"document fixture 5","expected":[[0,1],[],[0]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"document fixture 0\", \"actual\": [[0], [1], [1]], \"expected\": [[0], [1], [0]], \"passed\": false}, {\"check\": \"document fixture 1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"document fixture 2\", \"actual\": [[]], \"expected\": [[]], \"passed\": true}, {\"check\": \"document fixture 3\", \"actual\": [[0, 1], [0]], \"expected\": [[0, 1], [0]], \"passed\": true}, {\"check\": \"document fixture 4\", \"actual\": [[0], [1], [2], [2]], \"expected\": [[0], [1], [2], [0]], \"passed\": false}, {\"check\": \"document fixture 5\", \"actual\": [[0, 1], [], [1]], \"expected\": [[0, 1], [], [0]], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.532,"exit_code":1,"observations":[{"actual":[[0],[0],[0]],"check":"document fixture 0","expected":[[0],[1],[0]],"passed":false},{"actual":[],"check":"document fixture 1","expected":[],"passed":true},{"actual":[[]],"check":"document fixture 2","expected":[[]],"passed":true},{"actual":[[0,1],[0]],"check":"document fixture 3","expected":[[0,1],[0]],"passed":true},{"actual":[[0],[0],[0],[0]],"check":"document fixture 4","expected":[[0],[1],[2],[0]],"passed":false},{"actual":[[0,1],[],[0]],"check":"document fixture 5","expected":[[0,1],[],[0]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"document fixture 0\", \"actual\": [[0], [0], [0]], \"expected\": [[0], [1], [0]], \"passed\": false}, {\"check\": \"document fixture 1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"document fixture 2\", \"actual\": [[]], \"expected\": [[]], \"passed\": true}, {\"check\": \"document fixture 3\", \"actual\": [[0, 1], [0]], \"expected\": [[0, 1], [0]], \"passed\": true}, {\"check\": \"document fixture 4\", \"actual\": [[0], [0], [0], [0]], \"expected\": [[0], [1], [2], [0]], \"passed\": false}, {\"check\": \"document fixture 5\", \"actual\": [[0, 1], [], [0]], \"expected\": [[0, 1], [], [0]], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.629,"exit_code":0,"observations":[{"actual":[[0],[1],[0]],"check":"document fixture 0","expected":[[0],[1],[0]],"passed":true},{"actual":[],"check":"document fixture 1","expected":[],"passed":true},{"actual":[[]],"check":"document fixture 2","expected":[[]],"passed":true},{"actual":[[0,1],[0]],"check":"document fixture 3","expected":[[0,1],[0]],"passed":true},{"actual":[[0],[1],[2],[0]],"check":"document fixture 4","expected":[[0],[1],[2],[0]],"passed":true},{"actual":[[0,1],[],[0]],"check":"document fixture 5","expected":[[0,1],[],[0]],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"document fixture 0\", \"actual\": [[0], [1], [0]], \"expected\": [[0], [1], [0]], \"passed\": true}, {\"check\": \"document fixture 1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"document fixture 2\", \"actual\": [[]], \"expected\": [[]], \"passed\": true}, {\"check\": \"document fixture 3\", \"actual\": [[0, 1], [0]], \"expected\": [[0, 1], [0]], \"passed\": true}, {\"check\": \"document fixture 4\", \"actual\": [[0], [1], [2], [0]], \"expected\": [[0], [1], [2], [0]], \"passed\": true}, {\"check\": \"document fixture 5\", \"actual\": [[0, 1], [], [0]], \"expected\": [[0, 1], [], [0]], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}