FA-39536 / Tree accessibility / Open access

Exclusive sibling branch expansion: Pre-operation leaf-focus provenance is overwritten after recovery · case 01

Pre-operation leaf-focus provenance is overwritten after recovery produces the wrong hierarchical widget state in a regression fixture.

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ROOT CAUSE

The exclusive-branches contract is violated at `d['focus'] not in d['branches']` by replacing it with `focus not in d['branches']`.

THE FAILURE

The exclusive-branches contract is violated at `d['focus'] not in d['branches']` by replacing it with `focus not in d['branches']`.

Unsuccessful approach: The partial repair `d['focus'] in d['branches']` still violates a boundary or preservation case.

Case contract

Expanding a branch in exclusive mode closes its sibling branches and their descendants, but leaves ancestor and unrelated branch expansion intact. Expansion of disabled or leaf nodes is ignored. Focus within a newly closed sibling moves to that sibling root. Manual expansion survives later mode-off operation. Report whether pre-operation focus was a terminal row as provenance.

Why this case matters

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.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    allowed=d['target'] in d['branches'] and d['target'] not in d['disabled']
    siblings=[x for x in d['branches'] if x!=d['target'] and d['parents'].get(x)==d['parents'].get(d['target'])]
    closed_roots=set(siblings) if allowed and d['exclusive'] else set()
    closed={x for x in d['open'] if x in closed_roots or any(a in closed_roots for a in d['ancestors'].get(x,[]))}
    expanded=(set(d['open'])-closed)|({d['target']} if allowed else set())
    focusroot=next((a for a in d['ancestors'].get(d['focus'],[]) if a in closed_roots),None)
    focus=focusroot if focusroot is not None else d['focus']
    changed=sorted(expanded^set(d['open']))
    state={x:x in expanded for x in d['branches']}
    leaf_focus=focus not in d['branches']
    return [sorted(expanded),focus,changed,state,leaf_focus]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = {1: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False}, True])], 2: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False}, True])], 3: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1', 'v2'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False, 'v2': False}, True])], 4: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1', 'v2', 'v3'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False, 'v2': False, 'v3': False}, True])], 5: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1', 'v2', 'v3', 'v4'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False, 'v2': False, 'v3': False, 'v4': False}, True])]}
for label, data, expected in cases[N]:
    check(label, solve(data), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
close sibling	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, False]`	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, True]`	Failed
mode off	`[['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'a': True, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	`[['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'a': True, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	Passed
disabled target	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	Passed
leaf target	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	Passed
unrelated focus	`[['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, False]`	`[['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, False]`	Passed
already open target	`[['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, False]`	`[['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, True]`	Failed
deeper varying sibling	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True, 'v0': False}, False]`	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True, 'v0': False}, True]`	Failed

SHA-256 / b8ec799c14c1816f794d0c8ca6f9e4c19e9fa9408a0e6bd02f4520ae176fcc76

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(d):
    allowed=d['target'] in d['branches'] and d['target'] not in d['disabled']
    siblings=[x for x in d['branches'] if x!=d['target'] and d['parents'].get(x)==d['parents'].get(d['target'])]
    closed_roots=set(siblings) if allowed and d['exclusive'] else set()
    closed={x for x in d['open'] if x in closed_roots or any(a in closed_roots for a in d['ancestors'].get(x,[]))}
    expanded=(set(d['open'])-closed)|({d['target']} if allowed else set())
    focusroot=next((a for a in d['ancestors'].get(d['focus'],[]) if a in closed_roots),None)
    focus=focusroot if focusroot is not None else d['focus']
    changed=sorted(expanded^set(d['open']))
    state={x:x in expanded for x in d['branches']}
    leaf_focus=d['focus'] in d['branches']
    return [sorted(expanded),focus,changed,state,leaf_focus]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = {1: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False}, True])], 2: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False}, True])], 3: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1', 'v2'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False, 'v2': False}, True])], 4: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1', 'v2', 'v3'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False, 'v2': False, 'v3': False}, True])], 5: [('close sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('mode off', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': False, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'r': True, 'a': True, 'b': True, 'bb': True, 'q': True}, True]), ('disabled target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': ['a'], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('leaf target', {'target': 'c', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['b', 'bb', 'q', 'r'], 'c', [], {'r': True, 'a': False, 'b': True, 'bb': True, 'q': True}, True]), ('unrelated focus', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'q'}, [['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, False]), ('already open target', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'a', 'b', 'bb', 'q', 'aa'], 'ancestors': {'aa': ['r', 'a'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True}, True]), ('deeper varying sibling', {'target': 'a', 'branches': ['r', 'a', 'b', 'bb', 'q', 'v0', 'v1', 'v2', 'v3', 'v4'], 'disabled': [], 'parents': {'r': None, 'a': 'r', 'b': 'r', 'bb': 'b', 'q': None}, 'exclusive': True, 'open': ['r', 'b', 'bb', 'q'], 'ancestors': {'a': ['r'], 'b': ['r'], 'bb': ['r', 'b'], 'c': ['r', 'b', 'bb']}, 'focus': 'c'}, [['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'r': True, 'a': True, 'b': False, 'bb': False, 'q': True, 'v0': False, 'v1': False, 'v2': False, 'v3': False, 'v4': False}, True])]}
for label, data, expected in cases[N]:
    check(label, solve(data), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
close sibling	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, False]`	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, True]`	Failed
mode off	`[['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'a': True, 'b': True, 'bb': True, 'q': True, 'r': True}, False]`	`[['a', 'b', 'bb', 'q', 'r'], 'c', ['a'], {'a': True, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	Failed
disabled target	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, False]`	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	Failed
leaf target	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, False]`	`[['b', 'bb', 'q', 'r'], 'c', [], {'a': False, 'b': True, 'bb': True, 'q': True, 'r': True}, True]`	Failed
unrelated focus	`[['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, True]`	`[['a', 'q', 'r'], 'q', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, False]`	Failed
already open target	`[['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, False]`	`[['a', 'aa', 'q', 'r'], 'b', ['b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True}, True]`	Failed
deeper varying sibling	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True, 'v0': False}, False]`	`[['a', 'q', 'r'], 'b', ['a', 'b', 'bb'], {'a': True, 'b': False, 'bb': False, 'q': True, 'r': True, 'v0': False}, True]`	Failed

SHA-256 / ed6298595739c85cad51361c875c88da665598f6d088f6de8d6252e3b8142d2c

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 7 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Verification & scope

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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:43:22.133961+00:00.

Case digest / c263814f9c86b782c9b3fa1b5c5a0e9ba90c140b4b25b3f8a28a35871a2a2202