FA-41031 / Heap invariants / Open access

Heap meld preserves handles from the entire source ownership component · case 01

The bounded meld ownership certificate reports an incorrect accepted.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Heap meld preserves handles from the entire source ownership component.

VERIFIED REPAIR

Derive accepted using [x for x in d["handles"] if find(x) in (rd,rs)] under the stated bounded certificate contract.

Unsuccessful approach: The local patch uses [x for x in d["handles"] if find(x)==rd] and still violates the stated relation.

Case contract

A destructive heap meld uses owner union representatives. Parent mapping owner->owner is acyclic and includes every referenced owner. Merge source representative into destination representative; source wrapper becomes empty but live handles from either representative remain resolvable through the union. Report representatives before meld, parent mapping after meld, source size, destination size, accepted handle owners, and whether self-component meld is a no-op.

Why this case matters

This isolates an internal heap representation or priority-structure invariant using deterministic finite records.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(d):
    parents=d['parents']; dest=d['dest']; src=d['src']
    def find(x):
        while parents[x]!=x: x=parents[x]
        return x
    rd=find(dest); rs=find(src); out=dict(parents)
    if rs!=rd: out[rs]=rd
    return {'representatives': [rd,rs],
    'union': out,
    'source_size': d["source_size"] if rs==rd else 0,
    'destination_size': d["dest_size"] if rs==rd else d["dest_size"]+d["source_size"],
    'accepted': [x for x in d["handles"] if x in (dest,src)],
    'noop': rd==rs}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 3, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 3, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 4, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 4, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 6, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 6, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 7, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 7, 'accepted': ['a', 'b'], 'noop': False})]][N-1]
check('regression certificate 1', solve(cases[0][0]), cases[0][1])
check('regression certificate 2', solve(cases[1][0]), cases[1][1])
check('regression certificate 3', solve(cases[2][0]), cases[2][1])
check('regression certificate 4', solve(cases[3][0]), cases[3][1])
check('regression certificate 5', solve(cases[4][0]), cases[4][1])
check('regression certificate 6', solve(cases[5][0]), cases[5][1])
check('variant-dependent certificate', solve(cases[6][0]), cases[6][1])
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
regression certificate 1	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a'}}`	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a'}}`	Passed
regression certificate 2	`{'accepted': ['a'], 'destination_size': 4, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 4, 'union': {'a': 'a'}}`	`{'accepted': ['a'], 'destination_size': 4, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 4, 'union': {'a': 'a'}}`	Passed
regression certificate 3	`{'accepted': ['c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'd'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}}`	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'd'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}}`	Failed
regression certificate 4	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 5, 'union': {'a': 'a', 'b': 'a', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 5, 'union': {'a': 'a', 'b': 'a', 'c': 'c'}}`	Passed
regression certificate 5	`{'accepted': ['a', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}}`	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}}`	Failed
regression certificate 6	`{'accepted': ['a', 'b'], 'destination_size': 2, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 2, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	Passed
variant-dependent certificate	`{'accepted': ['a', 'b'], 'destination_size': 3, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 3, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	Passed

SHA-256 / 0e1ae57724e475130969024527a2daed915e6a249fe78eae39b04a57f7ad475a

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(d):
    parents=d['parents']; dest=d['dest']; src=d['src']
    def find(x):
        while parents[x]!=x: x=parents[x]
        return x
    rd=find(dest); rs=find(src); out=dict(parents)
    if rs!=rd: out[rs]=rd
    return {'representatives': [rd,rs],
    'union': out,
    'source_size': d["source_size"] if rs==rd else 0,
    'destination_size': d["dest_size"] if rs==rd else d["dest_size"]+d["source_size"],
    'accepted': [x for x in d["handles"] if find(x)==rd],
    'noop': rd==rs}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 3, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 3, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 4, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 4, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 6, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 6, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 7, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 7, 'accepted': ['a', 'b'], 'noop': False})]][N-1]
check('regression certificate 1', solve(cases[0][0]), cases[0][1])
check('regression certificate 2', solve(cases[1][0]), cases[1][1])
check('regression certificate 3', solve(cases[2][0]), cases[2][1])
check('regression certificate 4', solve(cases[3][0]), cases[3][1])
check('regression certificate 5', solve(cases[4][0]), cases[4][1])
check('regression certificate 6', solve(cases[5][0]), cases[5][1])
check('variant-dependent certificate', solve(cases[6][0]), cases[6][1])
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
regression certificate 1	`{'accepted': ['a'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a'}}`	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a'}}`	Failed
regression certificate 2	`{'accepted': ['a'], 'destination_size': 4, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 4, 'union': {'a': 'a'}}`	`{'accepted': ['a'], 'destination_size': 4, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 4, 'union': {'a': 'a'}}`	Passed
regression certificate 3	`{'accepted': ['a', 'b', 'c'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'd'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}}`	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'd'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}}`	Failed
regression certificate 4	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 5, 'union': {'a': 'a', 'b': 'a', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 5, 'union': {'a': 'a', 'b': 'a', 'c': 'c'}}`	Passed
regression certificate 5	`{'accepted': ['a'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}}`	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}}`	Failed
regression certificate 6	`{'accepted': ['b'], 'destination_size': 2, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 2, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	Failed
variant-dependent certificate	`{'accepted': ['b'], 'destination_size': 3, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 3, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	Failed

SHA-256 / 5f3f7cf06d714dc06aba1879b7141f906878e253980ff6fb9c2e3bce4b5c3e5c

3 / The verified repair

Exit 0

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

N = 1
observations = []
def solve(d):
    parents=d['parents']; dest=d['dest']; src=d['src']
    def find(x):
        while parents[x]!=x: x=parents[x]
        return x
    rd=find(dest); rs=find(src); out=dict(parents)
    if rs!=rd: out[rs]=rd
    return {'representatives': [rd,rs],
    'union': out,
    'source_size': d["source_size"] if rs==rd else 0,
    'destination_size': d["dest_size"] if rs==rd else d["dest_size"]+d["source_size"],
    'accepted': [x for x in d["handles"] if find(x) in (rd,rs)],
    'noop': rd==rs}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 3, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 3, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 4, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 4, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 6, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 6, 'accepted': ['a', 'b'], 'noop': False})], [({'parents': {'a': 'a', 'b': 'b'}, 'dest': 'a', 'src': 'b', 'dest_size': 2, 'source_size': 3, 'handles': ['a', 'b']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a'}, 'dest': 'a', 'src': 'a', 'dest_size': 4, 'source_size': 4, 'handles': ['a']}, {'representatives': ['a', 'a'], 'union': {'a': 'a'}, 'source_size': 4, 'destination_size': 4, 'accepted': ['a'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'd'}, 'dest': 'c', 'src': 'd', 'dest_size': 3, 'source_size': 2, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'd'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'a', 'c': 'c'}, 'dest': 'a', 'src': 'b', 'dest_size': 5, 'source_size': 5, 'handles': ['a', 'b', 'c']}, {'representatives': ['a', 'a'], 'union': {'a': 'a', 'b': 'a', 'c': 'c'}, 'source_size': 5, 'destination_size': 5, 'accepted': ['a', 'b'], 'noop': True}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'b', 'd': 'c'}, 'dest': 'a', 'src': 'd', 'dest_size': 1, 'source_size': 4, 'handles': ['a', 'b', 'c', 'd']}, {'representatives': ['a', 'b'], 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}, 'source_size': 0, 'destination_size': 5, 'accepted': ['a', 'b', 'c', 'd'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 2, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 2, 'accepted': ['a', 'b'], 'noop': False}), ({'parents': {'a': 'a', 'b': 'b', 'c': 'c'}, 'dest': 'b', 'src': 'a', 'dest_size': 0, 'source_size': 7, 'handles': ['a', 'b', 'c']}, {'representatives': ['b', 'a'], 'union': {'a': 'b', 'b': 'b', 'c': 'c'}, 'source_size': 0, 'destination_size': 7, 'accepted': ['a', 'b'], 'noop': False})]][N-1]
check('regression certificate 1', solve(cases[0][0]), cases[0][1])
check('regression certificate 2', solve(cases[1][0]), cases[1][1])
check('regression certificate 3', solve(cases[2][0]), cases[2][1])
check('regression certificate 4', solve(cases[3][0]), cases[3][1])
check('regression certificate 5', solve(cases[4][0]), cases[4][1])
check('regression certificate 6', solve(cases[5][0]), cases[5][1])
check('variant-dependent certificate', solve(cases[6][0]), cases[6][1])
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
regression certificate 1	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a'}}`	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a'}}`	Passed
regression certificate 2	`{'accepted': ['a'], 'destination_size': 4, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 4, 'union': {'a': 'a'}}`	`{'accepted': ['a'], 'destination_size': 4, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 4, 'union': {'a': 'a'}}`	Passed
regression certificate 3	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'd'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}}`	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'd'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'a'}}`	Passed
regression certificate 4	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 5, 'union': {'a': 'a', 'b': 'a', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 5, 'noop': True, 'representatives': ['a', 'a'], 'source_size': 5, 'union': {'a': 'a', 'b': 'a', 'c': 'c'}}`	Passed
regression certificate 5	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}}`	`{'accepted': ['a', 'b', 'c', 'd'], 'destination_size': 5, 'noop': False, 'representatives': ['a', 'b'], 'source_size': 0, 'union': {'a': 'a', 'b': 'a', 'c': 'b', 'd': 'c'}}`	Passed
regression certificate 6	`{'accepted': ['a', 'b'], 'destination_size': 2, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 2, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	Passed
variant-dependent certificate	`{'accepted': ['a', 'b'], 'destination_size': 3, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	`{'accepted': ['a', 'b'], 'destination_size': 3, 'noop': False, 'representatives': ['b', 'a'], 'source_size': 0, 'union': {'a': 'b', 'b': 'b', 'c': 'c'}}`	Passed

SHA-256 / 00ff04466186ba174f9669ab46bd4c97fbee4e7ec5ace64be6326bf0f08fb4af

Verification & scope

A stipulated offline diagnostic model; it does not implement a production allocator, concurrency protocol, or complete heap library. 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 2026-09-29T14:43:36.869619+00:00.

Case digest / 16df3314a4d31a8d1dc3f2c09c853db0baaff2ccdece00cff53099c45e4d1056