FAILURE MAP
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FA-86411 / Procedural level generation constraints / Open access

Key and lock solvability: Any key opens any lock · case 01

A blue key opens red doors, validating unsolvable dungeons.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The lock test only checks that some key is held.

VERIFIED REPAIR

Restore `(lock is None or lock in have)` at the lock matching step.

Unsuccessful approach: Requiring the key in the adjacent room ignores keys carried from elsewhere.

Case contract

rooms maps room -> keys lying there; edges [a, b, lock] are two-way doors, lock None or a key colour. Keys are never consumed. Starting in start, repeatedly pick up keys in visited rooms and walk through doors that are open or whose key is held, until nothing changes. Returns {solvable: goal visited, keys: sorted keys held, visited: count}.

Why this case matters

Procedural generators silently emit unplayable or unfair levels when a single constraint check uses the wrong boundary, axis, neighborhood or update order; the defect is visible in exact generated geometry.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(rooms, edges, start, goal):
    have = set()
    seen = {start}
    changed = True
    while changed:
        changed = False
        for r in list(seen):
            for k in rooms.get(r, []):
                if k not in have:
                    have.add(k)
                    changed = True
        for a, b, lock in edges:
            for u, v in ((a, b), (b, a)):
                if u in seen and v not in seen and (lock is None or bool(have)):
                    seen.add(v)
                    changed = True
    return {'solvable': goal in seen, 'keys': sorted(have), 'visited': len(seen)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['gold'], 'r1': ['red'], 'r2': ['gold']},
    [['r0', 'r1', 'red'], ['r2', 'r1', 'red'], ['r0', 'r2', None]],
    'r0',
    'r2'],
   {'solvable': True, 'keys': ['gold'], 'visited': 2}),
  ('fault site lock matching #2',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('partial repair boundary #1',
   [{'r0': ['gold'], 'r2': ['blue']},
    [['r2', 'r1', 'gold'],
     ['r3', 'r1', 'blue'],
     ['r1', 'r3', None],
     ['r1', 'r0', None],
     ['r2', 'r3', 'blue']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 4}),
  ('partial repair boundary #2',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression lock matching #1',
   [{'r3': ['blue'], 'r4': ['gold']},
    [['r4', 'r1', 'blue'],
     ['r5', 'r3', None],
     ['r5', 'r4', 'red'],
     ['r1', 'r0', 'gold'],
     ['r0', 'r2', 'blue'],
     ['r4', 'r0', None],
     ['r3', 'r2', None]],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['gold'], 'visited': 3}),
  ('regression lock matching #2',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r2': ['gold'], 'r3': ['red']},
    [['r2', 'r0', None], ['r2', 'r4', 'gold'], ['r5', 'r4', None], ['r3', 'r2', None], ['r0', 'r1', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 6}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('regression lock matching #1',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r2': ['gold'], 'r3': ['red']},
    [['r2', 'r0', None], ['r2', 'r4', 'gold'], ['r5', 'r4', None], ['r3', 'r2', None], ['r0', 'r1', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 6}),
  ('partial repair boundary #2',
   [{'r0': ['red'], 'r1': ['gold'], 'r2': ['red']},
    [['r0', 'r3', 'gold'],
     ['r2', 'r0', 'red'],
     ['r0', 'r1', 'gold'],
     ['r0', 'r4', None],
     ['r0', 'r1', 'red']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 5}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r1': ['red']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #2',
   [{'r0': ['gold'], 'r2': ['gold'], 'r3': ['red'], 'r4': ['red']},
    [['r0', 'r1', None],
     ['r1', 'r2', 'blue'],
     ['r6', 'r1', None],
     ['r5', 'r0', 'blue'],
     ['r3', 'r2', 'gold'],
     ['r4', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['gold', 'red'], 'visited': 4}),
  ('regression lock matching #1',
   [{'r0': ['blue'], 'r3': ['blue']},
    [['r3', 'r4', None],
     ['r1', 'r2', 'gold'],
     ['r1', 'r0', 'blue'],
     ['r1', 'r5', 'gold'],
     ['r3', 'r4', 'red'],
     ['r1', 'r3', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['blue']},
    [['r2', 'r0', 'red'], ['r1', 'r0', 'red'], ['r0', 'r1', 'blue'], ['r1', 'r2', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 3}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1',
   [{'r4': ['red']},
    [['r3', 'r1', 'gold'], ['r3', 'r4', 'blue'], ['r2', 'r1', None], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': [], 'visited': 3})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r2': ['red'], 'r3': ['blue'], 'r4': ['blue']},
    [['r3', 'r2', 'red'], ['r4', 'r0', None], ['r1', 'r2', 'red'], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['blue'], 'visited': 3}),
  ('regression lock matching #1',
   [{'r0': ['blue'], 'r3': ['blue']},
    [['r3', 'r4', None],
     ['r1', 'r2', 'gold'],
     ['r1', 'r0', 'blue'],
     ['r1', 'r5', 'gold'],
     ['r3', 'r4', 'red'],
     ['r1', 'r3', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['blue'], 'r2': ['blue'], 'r3': ['gold'], 'r4': ['gold']},
    [['r2', 'r0', None],
     ['r1', 'r0', 'blue'],
     ['r2', 'r4', 'blue'],
     ['r0', 'r3', None],
     ['r5', 'r1', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 6}),
  ('partial repair boundary #2',
   [{'r1': ['blue'], 'r2': ['gold'], 'r4': ['red']},
    [['r2', 'r0', None], ['r1', 'r0', None], ['r1', 'r4', None], ['r1', 'r3', None], ['r3', 'r5', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 6}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1',
   [{'r0': ['red']}, [['r0', 'r1', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2})]]
for label, args, expected in cases[N-1]:
    check(label, solve(*args), 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 fixtureActualExpectedOutcome
wrong colour #1{'keys': ['blue'], 'solvable': True, 'visited': 2}{'keys': ['blue'], 'solvable': False, 'visited': 1}Failed
fault site lock matching #1{'keys': ['gold', 'red'], 'solvable': True, 'visited': 3}{'keys': ['gold'], 'solvable': True, 'visited': 2}Failed
fault site lock matching #2{'keys': ['gold', 'red'], 'solvable': True, 'visited': 5}{'keys': ['red'], 'solvable': True, 'visited': 3}Failed
partial repair boundary #1{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}Passed
partial repair boundary #2{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}Passed
reverse listed door #1{'keys': [], 'solvable': True, 'visited': 2}{'keys': [], 'solvable': True, 'visited': 2}Passed
key behind first door #1{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
control #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': [], 'solvable': False, 'visited': 1}Passed

SHA-256 / 01ffdee0b666cf9bf86238fb24106addb47e19ff13a100cdc689e8a659370a0e

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(rooms, edges, start, goal):
    have = set()
    seen = {start}
    changed = True
    while changed:
        changed = False
        for r in list(seen):
            for k in rooms.get(r, []):
                if k not in have:
                    have.add(k)
                    changed = True
        for a, b, lock in edges:
            for u, v in ((a, b), (b, a)):
                if u in seen and v not in seen and (lock is None or lock in rooms.get(u, [])):
                    seen.add(v)
                    changed = True
    return {'solvable': goal in seen, 'keys': sorted(have), 'visited': len(seen)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['gold'], 'r1': ['red'], 'r2': ['gold']},
    [['r0', 'r1', 'red'], ['r2', 'r1', 'red'], ['r0', 'r2', None]],
    'r0',
    'r2'],
   {'solvable': True, 'keys': ['gold'], 'visited': 2}),
  ('fault site lock matching #2',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('partial repair boundary #1',
   [{'r0': ['gold'], 'r2': ['blue']},
    [['r2', 'r1', 'gold'],
     ['r3', 'r1', 'blue'],
     ['r1', 'r3', None],
     ['r1', 'r0', None],
     ['r2', 'r3', 'blue']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 4}),
  ('partial repair boundary #2',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression lock matching #1',
   [{'r3': ['blue'], 'r4': ['gold']},
    [['r4', 'r1', 'blue'],
     ['r5', 'r3', None],
     ['r5', 'r4', 'red'],
     ['r1', 'r0', 'gold'],
     ['r0', 'r2', 'blue'],
     ['r4', 'r0', None],
     ['r3', 'r2', None]],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['gold'], 'visited': 3}),
  ('regression lock matching #2',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r2': ['gold'], 'r3': ['red']},
    [['r2', 'r0', None], ['r2', 'r4', 'gold'], ['r5', 'r4', None], ['r3', 'r2', None], ['r0', 'r1', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 6}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('regression lock matching #1',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r2': ['gold'], 'r3': ['red']},
    [['r2', 'r0', None], ['r2', 'r4', 'gold'], ['r5', 'r4', None], ['r3', 'r2', None], ['r0', 'r1', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 6}),
  ('partial repair boundary #2',
   [{'r0': ['red'], 'r1': ['gold'], 'r2': ['red']},
    [['r0', 'r3', 'gold'],
     ['r2', 'r0', 'red'],
     ['r0', 'r1', 'gold'],
     ['r0', 'r4', None],
     ['r0', 'r1', 'red']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 5}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r1': ['red']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #2',
   [{'r0': ['gold'], 'r2': ['gold'], 'r3': ['red'], 'r4': ['red']},
    [['r0', 'r1', None],
     ['r1', 'r2', 'blue'],
     ['r6', 'r1', None],
     ['r5', 'r0', 'blue'],
     ['r3', 'r2', 'gold'],
     ['r4', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['gold', 'red'], 'visited': 4}),
  ('regression lock matching #1',
   [{'r0': ['blue'], 'r3': ['blue']},
    [['r3', 'r4', None],
     ['r1', 'r2', 'gold'],
     ['r1', 'r0', 'blue'],
     ['r1', 'r5', 'gold'],
     ['r3', 'r4', 'red'],
     ['r1', 'r3', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['blue']},
    [['r2', 'r0', 'red'], ['r1', 'r0', 'red'], ['r0', 'r1', 'blue'], ['r1', 'r2', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 3}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1',
   [{'r4': ['red']},
    [['r3', 'r1', 'gold'], ['r3', 'r4', 'blue'], ['r2', 'r1', None], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': [], 'visited': 3})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r2': ['red'], 'r3': ['blue'], 'r4': ['blue']},
    [['r3', 'r2', 'red'], ['r4', 'r0', None], ['r1', 'r2', 'red'], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['blue'], 'visited': 3}),
  ('regression lock matching #1',
   [{'r0': ['blue'], 'r3': ['blue']},
    [['r3', 'r4', None],
     ['r1', 'r2', 'gold'],
     ['r1', 'r0', 'blue'],
     ['r1', 'r5', 'gold'],
     ['r3', 'r4', 'red'],
     ['r1', 'r3', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['blue'], 'r2': ['blue'], 'r3': ['gold'], 'r4': ['gold']},
    [['r2', 'r0', None],
     ['r1', 'r0', 'blue'],
     ['r2', 'r4', 'blue'],
     ['r0', 'r3', None],
     ['r5', 'r1', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 6}),
  ('partial repair boundary #2',
   [{'r1': ['blue'], 'r2': ['gold'], 'r4': ['red']},
    [['r2', 'r0', None], ['r1', 'r0', None], ['r1', 'r4', None], ['r1', 'r3', None], ['r3', 'r5', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 6}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1',
   [{'r0': ['red']}, [['r0', 'r1', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2})]]
for label, args, expected in cases[N-1]:
    check(label, solve(*args), 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 fixtureActualExpectedOutcome
wrong colour #1{'keys': ['blue'], 'solvable': False, 'visited': 1}{'keys': ['blue'], 'solvable': False, 'visited': 1}Passed
fault site lock matching #1{'keys': ['gold'], 'solvable': True, 'visited': 2}{'keys': ['gold'], 'solvable': True, 'visited': 2}Passed
fault site lock matching #2{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
partial repair boundary #1{'keys': ['gold'], 'solvable': True, 'visited': 3}{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}Failed
partial repair boundary #2{'keys': ['blue', 'gold', 'red'], 'solvable': False, 'visited': 4}{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}Failed
reverse listed door #1{'keys': [], 'solvable': True, 'visited': 2}{'keys': [], 'solvable': True, 'visited': 2}Passed
key behind first door #1{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
control #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': [], 'solvable': False, 'visited': 1}Passed

SHA-256 / 4c25d1e6d322b9d6fd2c9b838748bfd079c2feed3aa43e1e7bfe8919f5b90cec

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(rooms, edges, start, goal):
    have = set()
    seen = {start}
    changed = True
    while changed:
        changed = False
        for r in list(seen):
            for k in rooms.get(r, []):
                if k not in have:
                    have.add(k)
                    changed = True
        for a, b, lock in edges:
            for u, v in ((a, b), (b, a)):
                if u in seen and v not in seen and (lock is None or lock in have):
                    seen.add(v)
                    changed = True
    return {'solvable': goal in seen, 'keys': sorted(have), 'visited': len(seen)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['gold'], 'r1': ['red'], 'r2': ['gold']},
    [['r0', 'r1', 'red'], ['r2', 'r1', 'red'], ['r0', 'r2', None]],
    'r0',
    'r2'],
   {'solvable': True, 'keys': ['gold'], 'visited': 2}),
  ('fault site lock matching #2',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('partial repair boundary #1',
   [{'r0': ['gold'], 'r2': ['blue']},
    [['r2', 'r1', 'gold'],
     ['r3', 'r1', 'blue'],
     ['r1', 'r3', None],
     ['r1', 'r0', None],
     ['r2', 'r3', 'blue']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 4}),
  ('partial repair boundary #2',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression lock matching #1',
   [{'r3': ['blue'], 'r4': ['gold']},
    [['r4', 'r1', 'blue'],
     ['r5', 'r3', None],
     ['r5', 'r4', 'red'],
     ['r1', 'r0', 'gold'],
     ['r0', 'r2', 'blue'],
     ['r4', 'r0', None],
     ['r3', 'r2', None]],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['gold'], 'visited': 3}),
  ('regression lock matching #2',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r2': ['gold'], 'r3': ['red']},
    [['r2', 'r0', None], ['r2', 'r4', 'gold'], ['r5', 'r4', None], ['r3', 'r2', None], ['r0', 'r1', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 6}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('regression lock matching #1',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r2': ['gold'], 'r3': ['red']},
    [['r2', 'r0', None], ['r2', 'r4', 'gold'], ['r5', 'r4', None], ['r3', 'r2', None], ['r0', 'r1', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 6}),
  ('partial repair boundary #2',
   [{'r0': ['red'], 'r1': ['gold'], 'r2': ['red']},
    [['r0', 'r3', 'gold'],
     ['r2', 'r0', 'red'],
     ['r0', 'r1', 'gold'],
     ['r0', 'r4', None],
     ['r0', 'r1', 'red']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['gold', 'red'], 'visited': 5}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r1': ['red']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #2',
   [{'r0': ['gold'], 'r2': ['gold'], 'r3': ['red'], 'r4': ['red']},
    [['r0', 'r1', None],
     ['r1', 'r2', 'blue'],
     ['r6', 'r1', None],
     ['r5', 'r0', 'blue'],
     ['r3', 'r2', 'gold'],
     ['r4', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['gold', 'red'], 'visited': 4}),
  ('regression lock matching #1',
   [{'r0': ['blue'], 'r3': ['blue']},
    [['r3', 'r4', None],
     ['r1', 'r2', 'gold'],
     ['r1', 'r0', 'blue'],
     ['r1', 'r5', 'gold'],
     ['r3', 'r4', 'red'],
     ['r1', 'r3', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['blue']},
    [['r2', 'r0', 'red'], ['r1', 'r0', 'red'], ['r0', 'r1', 'blue'], ['r1', 'r2', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 3}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1',
   [{'r4': ['red']},
    [['r3', 'r1', 'gold'], ['r3', 'r4', 'blue'], ['r2', 'r1', None], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': [], 'visited': 3})],
 [('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('fault site lock matching #1',
   [{'r0': ['blue'], 'r2': ['red'], 'r3': ['blue'], 'r4': ['blue']},
    [['r3', 'r2', 'red'], ['r4', 'r0', None], ['r1', 'r2', 'red'], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['blue'], 'visited': 3}),
  ('regression lock matching #1',
   [{'r0': ['blue'], 'r3': ['blue']},
    [['r3', 'r4', None],
     ['r1', 'r2', 'gold'],
     ['r1', 'r0', 'blue'],
     ['r1', 'r5', 'gold'],
     ['r3', 'r4', 'red'],
     ['r1', 'r3', 'blue']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['blue'], 'r2': ['blue'], 'r3': ['gold'], 'r4': ['gold']},
    [['r2', 'r0', None],
     ['r1', 'r0', 'blue'],
     ['r2', 'r4', 'blue'],
     ['r0', 'r3', None],
     ['r5', 'r1', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 6}),
  ('partial repair boundary #2',
   [{'r1': ['blue'], 'r2': ['gold'], 'r4': ['red']},
    [['r2', 'r0', None], ['r1', 'r0', None], ['r1', 'r4', None], ['r1', 'r3', None], ['r3', 'r5', 'gold']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 6}),
  ('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('control #1',
   [{'r0': ['red']}, [['r0', 'r1', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2})]]
for label, args, expected in cases[N-1]:
    check(label, solve(*args), 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 fixtureActualExpectedOutcome
wrong colour #1{'keys': ['blue'], 'solvable': False, 'visited': 1}{'keys': ['blue'], 'solvable': False, 'visited': 1}Passed
fault site lock matching #1{'keys': ['gold'], 'solvable': True, 'visited': 2}{'keys': ['gold'], 'solvable': True, 'visited': 2}Passed
fault site lock matching #2{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
partial repair boundary #1{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}Passed
partial repair boundary #2{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}Passed
reverse listed door #1{'keys': [], 'solvable': True, 'visited': 2}{'keys': [], 'solvable': True, 'visited': 2}Passed
key behind first door #1{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
control #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': [], 'solvable': False, 'visited': 1}Passed

SHA-256 / 9db0a04543d8cab646e48b6a52513e2d98308fec71c6b90b9f5a7663f9602f08

Verification & scope

Deterministic toy contract stipulated for this model; integer or exact arithmetic only, not a reproduction of any specific game engine. 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 2026-09-29T14:50:49.326854+00:00.

Case digest / a8871eb7a02d6ff3bfdd262d64addbafaf9faa5543cf77562ec1db58fe7e3e7b