{"abstract":"Virtual row index drops the offscreen prefix produces the wrong hierarchical widget state in a regression fixture.","category":"Tree accessibility","checks":6,"contract":"Rows carry id,parent,logical sibling index,known sibling count,depth. The viewport must expose global sibling positions and counts, one-based depth, root ownership, expandable state only for branches, and stable identity independent of recycled slots.","contract_signature":"d","evaluation_group":"s3-tree-virtual-siblings","failed_approach":"The partial repair `d['offset']+d['slot']` still violates a boundary or preservation case.","family":"s3-tree_accessibility-virtual-siblings-09","id":"FA-38481","implementations":{"attempt":{"sha256":"e4be56876e0282da0ce204e86d5286a06bb2232777c590e014a98f0694990ac2","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(d):\n    r=d['row']\n    position=r['index']+1\n    size=r['count'] if r['known'] else -1\n    level=r['depth']+1\n    owner=r['parent'] if r['parent'] is not None else d['tree']\n    expanded=r['open'] if r['branch'] else None\n    selected=r['id'] in d['selected']\n    active=r['id']==d['active']\n    dom=d['tree']+':'+r['id']\n    rowindex=d['offset']+d['slot']\n    busy=r['loading'] and r['branch']\n    return [position,size,level,owner,expanded,selected,active,dom,rowindex,busy]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncases = {1: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'p', True, True, True, 'tree:b', 5, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'tree', True, False, False, 'tree:b', 5, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'p', None, True, False, 'tree:b', 5, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': False, 'depth': 1, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, -1, 2, 'p', True, False, True, 'tree:b', 5, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'p', True, False, False, 'tree:b', 5, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 9, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 3, 'slot': 1, 'mounted': 3}, [1, 9, 1, 'p', False, False, True, 'tree:b', 5, True])], 2: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'p', True, True, True, 'tree:b', 8, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'tree', True, False, False, 'tree:b', 8, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'p', None, True, False, 'tree:b', 8, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': False, 'depth': 2, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, -1, 3, 'p', True, False, True, 'tree:b', 8, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'p', True, False, False, 'tree:b', 8, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 10, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 6, 'slot': 1, 'mounted': 3}, [1, 10, 1, 'p', False, False, True, 'tree:b', 8, True])], 3: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'p', True, True, True, 'tree:b', 11, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'tree', True, False, False, 'tree:b', 11, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'p', None, True, False, 'tree:b', 11, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': False, 'depth': 3, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, -1, 4, 'p', True, False, True, 'tree:b', 11, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'p', True, False, False, 'tree:b', 11, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 11, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 9, 'slot': 1, 'mounted': 3}, [1, 11, 1, 'p', False, False, True, 'tree:b', 11, True])], 4: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'p', True, True, True, 'tree:b', 14, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'tree', True, False, False, 'tree:b', 14, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'p', None, True, False, 'tree:b', 14, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': False, 'depth': 4, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, -1, 5, 'p', True, False, True, 'tree:b', 14, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'p', True, False, False, 'tree:b', 14, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 12, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 12, 'slot': 1, 'mounted': 3}, [1, 12, 1, 'p', False, False, True, 'tree:b', 14, True])], 5: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'p', True, True, True, 'tree:b', 17, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'tree', True, False, False, 'tree:b', 17, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'p', None, True, False, 'tree:b', 17, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': False, 'depth': 5, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, -1, 6, 'p', True, False, True, 'tree:b', 17, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'p', True, False, False, 'tree:b', 17, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 13, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 15, 'slot': 1, 'mounted': 3}, [1, 13, 1, 'p', False, False, True, 'tree:b', 17, True])]}\nfor label, data, expected in cases[N]:\n    check(label, solve(data), 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":"ce4aed1cb1d40403e67e808f5d0fc3b32b50cb941324df7a6f31bbc0beb1e80f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(d):\n    r=d['row']\n    position=r['index']+1\n    size=r['count'] if r['known'] else -1\n    level=r['depth']+1\n    owner=r['parent'] if r['parent'] is not None else d['tree']\n    expanded=r['open'] if r['branch'] else None\n    selected=r['id'] in d['selected']\n    active=r['id']==d['active']\n    dom=d['tree']+':'+r['id']\n    rowindex=d['slot']+1\n    busy=r['loading'] and r['branch']\n    return [position,size,level,owner,expanded,selected,active,dom,rowindex,busy]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncases = {1: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'p', True, True, True, 'tree:b', 5, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'tree', True, False, False, 'tree:b', 5, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'p', None, True, False, 'tree:b', 5, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': False, 'depth': 1, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, -1, 2, 'p', True, False, True, 'tree:b', 5, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 3, 'count': 9, 'known': True, 'depth': 1, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 3, 'slot': 1, 'mounted': 3}, [4, 9, 2, 'p', True, False, False, 'tree:b', 5, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 9, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 3, 'slot': 1, 'mounted': 3}, [1, 9, 1, 'p', False, False, True, 'tree:b', 5, True])], 2: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'p', True, True, True, 'tree:b', 8, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'tree', True, False, False, 'tree:b', 8, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'p', None, True, False, 'tree:b', 8, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': False, 'depth': 2, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, -1, 3, 'p', True, False, True, 'tree:b', 8, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 4, 'count': 10, 'known': True, 'depth': 2, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 6, 'slot': 1, 'mounted': 3}, [5, 10, 3, 'p', True, False, False, 'tree:b', 8, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 10, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 6, 'slot': 1, 'mounted': 3}, [1, 10, 1, 'p', False, False, True, 'tree:b', 8, True])], 3: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'p', True, True, True, 'tree:b', 11, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'tree', True, False, False, 'tree:b', 11, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'p', None, True, False, 'tree:b', 11, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': False, 'depth': 3, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, -1, 4, 'p', True, False, True, 'tree:b', 11, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 5, 'count': 11, 'known': True, 'depth': 3, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 9, 'slot': 1, 'mounted': 3}, [6, 11, 4, 'p', True, False, False, 'tree:b', 11, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 11, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 9, 'slot': 1, 'mounted': 3}, [1, 11, 1, 'p', False, False, True, 'tree:b', 11, True])], 4: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'p', True, True, True, 'tree:b', 14, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'tree', True, False, False, 'tree:b', 14, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'p', None, True, False, 'tree:b', 14, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': False, 'depth': 4, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, -1, 5, 'p', True, False, True, 'tree:b', 14, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 6, 'count': 12, 'known': True, 'depth': 4, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 12, 'slot': 1, 'mounted': 3}, [7, 12, 5, 'p', True, False, False, 'tree:b', 14, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 12, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 12, 'slot': 1, 'mounted': 3}, [1, 12, 1, 'p', False, False, True, 'tree:b', 14, True])], 5: [('branch', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': True, 'loading': True}, 'selected': ['b'], 'active': 'b', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'p', True, True, True, 'tree:b', 17, True]), ('root', {'tree': 'tree', 'row': {'id': 'b', 'parent': None, 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'x', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'tree', True, False, False, 'tree:b', 17, True]), ('leaf', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': False, 'loading': True}, 'selected': ['b'], 'active': 'x', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'p', None, True, False, 'tree:b', 17, False]), ('unknown', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': False, 'depth': 5, 'open': True, 'branch': True, 'loading': True}, 'selected': [], 'active': 'b', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, -1, 6, 'p', True, False, True, 'tree:b', 17, True]), ('idle', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 7, 'count': 13, 'known': True, 'depth': 5, 'open': True, 'branch': True, 'loading': False}, 'selected': ['x'], 'active': 'x', 'offset': 15, 'slot': 1, 'mounted': 3}, [8, 13, 6, 'p', True, False, False, 'tree:b', 17, False]), ('collapsed', {'tree': 'tree', 'row': {'id': 'b', 'parent': 'p', 'index': 0, 'count': 13, 'known': True, 'depth': 0, 'open': False, 'branch': True, 'loading': True}, 'selected': ['x'], 'active': 'b', 'offset': 15, 'slot': 1, 'mounted': 3}, [1, 13, 1, 'p', False, False, True, 'tree:b', 17, True])]}\nfor label, data, expected in cases[N]:\n    check(label, solve(data), 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":"Synthetic deterministic hierarchical-widget data contract; not an implementation of a browser accessibility tree. 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-tree_accessibility-virtual-siblings-09","generated_at":"2026-09-29T14:43:11.695838+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Offline executable model of a hierarchical accessibility interaction; inputs are bounded and valid as stipulated. No browser, assistive technology, or normative ARIA conformance is claimed.","root_cause":"The virtual-siblings contract is violated at `d['offset']+d['slot']+1` by replacing it with `d['slot']+1`.","sha256":"33395c95ea10b16732c7705fa0867044a3270b676ef01ee512bb490b9cbdd1ef","title":"Virtual tree sibling metadata: Virtual row index drops the offscreen prefix · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":45.374,"exit_code":1,"observations":[{"actual":[4,9,2,"p",true,true,true,"tree:b",4,true],"check":"branch","expected":[4,9,2,"p",true,true,true,"tree:b",5,true],"passed":false},{"actual":[4,9,2,"tree",true,false,false,"tree:b",4,true],"check":"root","expected":[4,9,2,"tree",true,false,false,"tree:b",5,true],"passed":false},{"actual":[4,9,2,"p",null,true,false,"tree:b",4,false],"check":"leaf","expected":[4,9,2,"p",null,true,false,"tree:b",5,false],"passed":false},{"actual":[4,-1,2,"p",true,false,true,"tree:b",4,true],"check":"unknown","expected":[4,-1,2,"p",true,false,true,"tree:b",5,true],"passed":false},{"actual":[4,9,2,"p",true,false,false,"tree:b",4,false],"check":"idle","expected":[4,9,2,"p",true,false,false,"tree:b",5,false],"passed":false},{"actual":[1,9,1,"p",false,false,true,"tree:b",4,true],"check":"collapsed","expected":[1,9,1,"p",false,false,true,"tree:b",5,true],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"branch\", \"actual\": [4, 9, 2, \"p\", true, true, true, \"tree:b\", 4, true], \"expected\": [4, 9, 2, \"p\", true, true, true, \"tree:b\", 5, true], \"passed\": false}, {\"check\": \"root\", \"actual\": [4, 9, 2, \"tree\", true, false, false, \"tree:b\", 4, true], \"expected\": [4, 9, 2, \"tree\", true, false, false, \"tree:b\", 5, true], \"passed\": false}, {\"check\": \"leaf\", \"actual\": [4, 9, 2, \"p\", null, true, false, \"tree:b\", 4, false], \"expected\": [4, 9, 2, \"p\", null, true, false, \"tree:b\", 5, false], \"passed\": false}, {\"check\": \"unknown\", \"actual\": [4, -1, 2, \"p\", true, false, true, \"tree:b\", 4, true], \"expected\": [4, -1, 2, \"p\", true, false, true, \"tree:b\", 5, true], \"passed\": false}, {\"check\": \"idle\", \"actual\": [4, 9, 2, \"p\", true, false, false, \"tree:b\", 4, false], \"expected\": [4, 9, 2, \"p\", true, false, false, \"tree:b\", 5, false], \"passed\": false}, {\"check\": \"collapsed\", \"actual\": [1, 9, 1, \"p\", false, false, true, \"tree:b\", 4, true], \"expected\": [1, 9, 1, \"p\", false, false, true, \"tree:b\", 5, true], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.952,"exit_code":1,"observations":[{"actual":[4,9,2,"p",true,true,true,"tree:b",2,true],"check":"branch","expected":[4,9,2,"p",true,true,true,"tree:b",5,true],"passed":false},{"actual":[4,9,2,"tree",true,false,false,"tree:b",2,true],"check":"root","expected":[4,9,2,"tree",true,false,false,"tree:b",5,true],"passed":false},{"actual":[4,9,2,"p",null,true,false,"tree:b",2,false],"check":"leaf","expected":[4,9,2,"p",null,true,false,"tree:b",5,false],"passed":false},{"actual":[4,-1,2,"p",true,false,true,"tree:b",2,true],"check":"unknown","expected":[4,-1,2,"p",true,false,true,"tree:b",5,true],"passed":false},{"actual":[4,9,2,"p",true,false,false,"tree:b",2,false],"check":"idle","expected":[4,9,2,"p",true,false,false,"tree:b",5,false],"passed":false},{"actual":[1,9,1,"p",false,false,true,"tree:b",2,true],"check":"collapsed","expected":[1,9,1,"p",false,false,true,"tree:b",5,true],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"branch\", \"actual\": [4, 9, 2, \"p\", true, true, true, \"tree:b\", 2, true], \"expected\": [4, 9, 2, \"p\", true, true, true, \"tree:b\", 5, true], \"passed\": false}, {\"check\": \"root\", \"actual\": [4, 9, 2, \"tree\", true, false, false, \"tree:b\", 2, true], \"expected\": [4, 9, 2, \"tree\", true, false, false, \"tree:b\", 5, true], \"passed\": false}, {\"check\": \"leaf\", \"actual\": [4, 9, 2, \"p\", null, true, false, \"tree:b\", 2, false], \"expected\": [4, 9, 2, \"p\", null, true, false, \"tree:b\", 5, false], \"passed\": false}, {\"check\": \"unknown\", \"actual\": [4, -1, 2, \"p\", true, false, true, \"tree:b\", 2, true], \"expected\": [4, -1, 2, \"p\", true, false, true, \"tree:b\", 5, true], \"passed\": false}, {\"check\": \"idle\", \"actual\": [4, 9, 2, \"p\", true, false, false, \"tree:b\", 2, false], \"expected\": [4, 9, 2, \"p\", true, false, false, \"tree:b\", 5, false], \"passed\": false}, {\"check\": \"collapsed\", \"actual\": [1, 9, 1, \"p\", false, false, true, \"tree:b\", 2, true], \"expected\": [1, 9, 1, \"p\", false, false, true, \"tree:b\", 5, true], \"passed\": false}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}