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FA-68296 / Traffic signal timing plans / Open access

Conflict monitor fault scan: disabled channels showing green still enter the conflict check · case 01

Conflict monitor fault scan returns a wrong result when disabled channels showing green still enter the conflict check.

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

ROOT CAUSE

Only dark disabled channels are skipped, so unused load switches take part in conflict and multi checks.

THE FAILURE

Only dark disabled channels are skipped, so unused load switches take part in conflict and multi checks.

Unsuccessful approach: Skipping disabled channels only when red or dark still monitors disabled channels that show G or Y.

Case contract

Input {channels: [[channel, lit colors string over R/Y/G, enabled]], compat: unordered compatible pairs, yellow_durations: [[channel, tenths]]}. Disabled channels are ignored entirely. A channel with more than one lit color is 'multi'; with none lit is 'red-fail'; any channel showing G or Y takes part in the conflict check, and every live pair not listed as compatible is 'conflict:a-b' (a<b). A completed yellow shorter than 2.7 s is 'short-yellow'. Return the sorted fault strings.

Why this case matters

Signal timing arithmetic is exact and integer or rational; a wrong rule silently produces unsafe or inefficient timing plans.

1 / The failure

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

N = 1
observations = []
def solve(x):
    ok = {(min(a, b), max(a, b)) for a, b in x['compat']}
    faults = []
    live = []
    for ch, col, en in x['channels']:
        if not en and not col:
            continue
        if len(col) > 1:
            faults.append('multi:%d' % ch)
        if col == '':
            faults.append('red-fail:%d' % ch)
        if 'G' in col or 'Y' in col:
            live.append(ch)
    live.sort()
    for i in range(len(live)):
        for j in range(i + 1, len(live)):
            if (live[i], live[j]) not in ok:
                faults.append('conflict:%d-%d' % (live[i], live[j]))
    for ch, tenths in x['yellow_durations']:
        if tenths < 27:
            faults.append('short-yellow:%d' % ch)
    return sorted(faults)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[({'channels': [[1, 'R', True], [2, '', True], [3, 'R', True], [4, 'R', True], [5, 'RY', True]], 'compat': [[1, 5], [5, 2], [3, 5]], 'yellow_durations': [[1, 35], [2, 35], [3, 27]]}, ['multi:5', 'red-fail:2']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'R', True], [2, 'Y', True], [3, 'R', True]], 'compat': [], 'yellow_durations': []}, []), ({'channels': [[1, 'RG', False], [2, 'R', True], [3, 'G', True], [4, 'Y', True]], 'compat': [[1, 3], [1, 4]], 'yellow_durations': [[2, 30], [4, 27]]}, ['conflict:3-4']), ({'channels': [[1, 'Y', True], [2, '', True], [3, 'R', True], [4, 'R', True], [5, 'Y', True]], 'compat': [[5, 1], [2, 4], [5, 2]], 'yellow_durations': [[3, 30], [4, 35], [5, 26]]}, ['red-fail:2', 'short-yellow:5']), ({'channels': [[1, 'RY', True], [2, 'R', True], [3, 'R', True], [4, 'RY', False], [5, 'Y', True]], 'compat': [[1, 4], [2, 5], [3, 4]], 'yellow_durations': []}, ['conflict:1-5', 'multi:1']), ({'channels': [[1, 'GY', True], [2, '', True], [3, '', True], [4, '', True], [5, '', True], [6, 'RY', True]], 'compat': [[4, 1], [1, 5], [4, 2], [6, 2]], 'yellow_durations': [[2, 35]]}, ['conflict:1-6', 'multi:1', 'multi:6', 'red-fail:2', 'red-fail:3', 'red-fail:4', 'red-fail:5'])], [({'channels': [[1, 'Y', True], [2, 'RG', True], [3, 'GY', True], [4, 'Y', True], [5, 'RG', True]], 'compat': [[1, 2], [4, 1], [5, 2], [3, 5]], 'yellow_durations': [[1, 26], [2, 27], [3, 25], [4, 27]]}, ['conflict:1-3', 'conflict:1-5', 'conflict:2-3', 'conflict:2-4', 'conflict:3-4', 'conflict:4-5', 'multi:2', 'multi:3', 'multi:5', 'short-yellow:1', 'short-yellow:3']), ({'channels': [[1, 'RY', True], [2, 'R', True], [3, 'RY', True], [4, '', True], [5, '', True], [6, 'RG', True]], 'compat': [[2, 1], [1, 3], [4, 1], [5, 1], [2, 3], [4, 2], [2, 5], [4, 3], [6, 4], [6, 5]], 'yellow_durations': [[2, 26]]}, ['conflict:1-6', 'conflict:3-6', 'multi:1', 'multi:3', 'multi:6', 'red-fail:4', 'red-fail:5', 'short-yellow:2']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'R', False], [2, '', True], [3, '', True], [4, 'RY', False], [5, 'RY', True]], 'compat': [[1, 4], [1, 5]], 'yellow_durations': [[1, 26], [2, 28], [4, 26]]}, ['multi:5', 'red-fail:2', 'red-fail:3', 'short-yellow:1', 'short-yellow:4']), ({'channels': [[1, 'GY', True], [2, 'RY', True], [3, 'G', True]], 'compat': [[3, 2]], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'conflict:1-3', 'multi:1', 'multi:2', 'short-yellow:1']), ({'channels': [[1, 'R', True], [2, 'Y', True], [3, 'GY', True], [4, 'R', True], [5, 'RY', False]], 'compat': [[2, 3], [4, 2], [2, 5], [4, 3]], 'yellow_durations': [[5, 35]]}, ['multi:3']), ({'channels': [[1, 'R', True], [2, 'RY', True], [3, 'GY', True]], 'compat': [[1, 2]], 'yellow_durations': [[3, 30]]}, ['conflict:2-3', 'multi:2', 'multi:3']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1'])], [({'channels': [[1, 'R', True], [2, 'R', True], [3, 'R', True]], 'compat': [], 'yellow_durations': [[3, 25]]}, ['short-yellow:3']), ({'channels': [[1, 'R', True], [2, 'RY', False], [3, 'R', True], [4, 'RG', True], [5, '', True]], 'compat': [[2, 3], [3, 4], [4, 5]], 'yellow_durations': [[1, 35], [2, 28], [3, 26], [4, 26], [5, 30]]}, ['multi:4', 'red-fail:5', 'short-yellow:3', 'short-yellow:4']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'RY', True], [2, 'RY', False], [3, 'RY', True], [4, 'RY', True]], 'compat': [[1, 2], [1, 4], [2, 3]], 'yellow_durations': [[1, 28], [3, 35]]}, ['conflict:1-3', 'conflict:3-4', 'multi:1', 'multi:3', 'multi:4']), ({'channels': [[1, 'R', False], [2, 'RY', True], [3, 'R', False], [4, 'GY', True], [5, 'GY', True], [6, 'R', True]], 'compat': [[3, 1], [5, 2], [6, 2], [3, 4], [5, 3], [4, 5]], 'yellow_durations': [[1, 25], [2, 28], [3, 27], [4, 28], [5, 35]]}, ['conflict:2-4', 'multi:2', 'multi:4', 'multi:5', 'short-yellow:1']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'Y', True], [2, '', True], [3, 'RY', True], [4, 'RG', True]], 'compat': [[2, 1], [3, 1], [1, 4], [4, 2]], 'yellow_durations': [[3, 26]]}, ['conflict:3-4', 'multi:3', 'multi:4', 'red-fail:2', 'short-yellow:3']), ({'channels': [[1, 'R', True], [2, '', True], [3, 'RG', True]], 'compat': [[1, 2], [1, 3]], 'yellow_durations': [[1, 30]]}, ['multi:3', 'red-fail:2'])], [({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'R', True], [2, 'R', True], [3, 'R', True]], 'compat': [], 'yellow_durations': [[1, 30]]}, []), ({'channels': [[1, 'R', True], [2, 'Y', True], [3, 'R', True]], 'compat': [[1, 2]], 'yellow_durations': [[1, 27], [2, 25], [3, 26]]}, ['short-yellow:2', 'short-yellow:3']), ({'channels': [[1, 'R', True], [2, '', True], [3, 'R', True], [4, 'RY', True]], 'compat': [[1, 3], [1, 4], [4, 2]], 'yellow_durations': [[3, 26]]}, ['multi:4', 'red-fail:2', 'short-yellow:3']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'Y', False], [2, 'RG', False], [3, 'R', True]], 'compat': [[3, 2]], 'yellow_durations': [[3, 26]]}, ['short-yellow:3']), ({'channels': [[1, 'RG', True], [2, 'RY', False], [3, 'RG', True], [4, 'R', True], [5, 'GY', True]], 'compat': [[1, 2], [4, 3], [5, 4]], 'yellow_durations': [[5, 27]]}, ['conflict:1-3', 'conflict:1-5', 'conflict:3-5', 'multi:1', 'multi:3', 'multi:5']), ({'channels': [[1, 'RY', False], [2, 'R', True], [3, 'RY', True], [4, 'R', True], [5, 'G', True], [6, 'G', True]], 'compat': [[1, 2], [5, 1], [6, 2], [3, 4], [5, 4], [6, 4]], 'yellow_durations': [[3, 25], [5, 25]]}, ['conflict:3-5', 'conflict:3-6', 'conflict:5-6', 'multi:3', 'short-yellow:3', 'short-yellow:5'])], [({'channels': [[1, 'Y', True], [2, 'R', True], [3, 'R', True], [4, '', True], [5, 'RY', True], [6, 'G', True]], 'compat': [[6, 1], [3, 4], [3, 6], [4, 6], [6, 5]], 'yellow_durations': [[3, 30]]}, ['conflict:1-5', 'multi:5', 'red-fail:4']), ({'channels': [[1, 'Y', True], [2, 'RG', False], [3, 'G', True], [4, 'RG', True], [5, 'RY', True]], 'compat': [[1, 2], [1, 4], [5, 1], [3, 2], [4, 2], [3, 5]], 'yellow_durations': [[1, 30]]}, ['conflict:1-3', 'conflict:3-4', 'conflict:4-5', 'multi:4', 'multi:5']), ({'channels': [[1, 'R', True], [2, 'R', True], [3, 'G', True], [4, 'GY', True]], 'compat': [[3, 2], [3, 4]], 'yellow_durations': [[4, 27]]}, ['multi:4']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'Y', True], [2, 'RG', False], [3, 'R', False], [4, 'GY', False], [5, 'RY', True]], 'compat': [[1, 2], [2, 4], [3, 4]], 'yellow_durations': [[3, 27]]}, ['conflict:1-5', 'multi:5']), ({'channels': [[1, 'R', True], [2, 'R', True], [3, 'GY', True]], 'compat': [[2, 1]], 'yellow_durations': [[2, 28]]}, ['multi:3']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'G', True], [2, 'RY', True], [3, 'R', True], [4, '', True]], 'compat': [[1, 2], [3, 1], [1, 4], [3, 4]], 'yellow_durations': [[3, 30]]}, ['multi:2', 'red-fail:4'])]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check('timing oracle' + ' %d' % i, 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
timing oracle 0['multi:5', 'red-fail:2']['multi:5', 'red-fail:2']Passed
timing oracle 1['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']Passed
timing oracle 2['conflict:1-4', 'conflict:3-4'][]Failed
timing oracle 3[][]Passed
timing oracle 4['conflict:3-4', 'multi:1']['conflict:3-4']Failed
timing oracle 5['red-fail:2', 'short-yellow:5']['red-fail:2', 'short-yellow:5']Passed
timing oracle 6['conflict:1-5', 'conflict:4-5', 'multi:1', 'multi:4']['conflict:1-5', 'multi:1']Failed
timing oracle 7['conflict:1-6', 'multi:1', 'multi:6', 'red-fail:2', 'red-fail:3', 'red-fail:4', 'red-fail:5']['conflict:1-6', 'multi:1', 'multi:6', 'red-fail:2', 'red-fail:3', 'red-fail:4', 'red-fail:5']Passed

SHA-256 / acd483a6c3fb001f40080e8160cad494f0cc29db95bd3ce7cfbe38941059cf3f

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(x):
    ok = {(min(a, b), max(a, b)) for a, b in x['compat']}
    faults = []
    live = []
    for ch, col, en in x['channels']:
        if not en and col in ('', 'R'):
            continue
        if len(col) > 1:
            faults.append('multi:%d' % ch)
        if col == '':
            faults.append('red-fail:%d' % ch)
        if 'G' in col or 'Y' in col:
            live.append(ch)
    live.sort()
    for i in range(len(live)):
        for j in range(i + 1, len(live)):
            if (live[i], live[j]) not in ok:
                faults.append('conflict:%d-%d' % (live[i], live[j]))
    for ch, tenths in x['yellow_durations']:
        if tenths < 27:
            faults.append('short-yellow:%d' % ch)
    return sorted(faults)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[({'channels': [[1, 'R', True], [2, '', True], [3, 'R', True], [4, 'R', True], [5, 'RY', True]], 'compat': [[1, 5], [5, 2], [3, 5]], 'yellow_durations': [[1, 35], [2, 35], [3, 27]]}, ['multi:5', 'red-fail:2']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'R', True], [2, 'Y', True], [3, 'R', True]], 'compat': [], 'yellow_durations': []}, []), ({'channels': [[1, 'RG', False], [2, 'R', True], [3, 'G', True], [4, 'Y', True]], 'compat': [[1, 3], [1, 4]], 'yellow_durations': [[2, 30], [4, 27]]}, ['conflict:3-4']), ({'channels': [[1, 'Y', True], [2, '', True], [3, 'R', True], [4, 'R', True], [5, 'Y', True]], 'compat': [[5, 1], [2, 4], [5, 2]], 'yellow_durations': [[3, 30], [4, 35], [5, 26]]}, ['red-fail:2', 'short-yellow:5']), ({'channels': [[1, 'RY', True], [2, 'R', True], [3, 'R', True], [4, 'RY', False], [5, 'Y', True]], 'compat': [[1, 4], [2, 5], [3, 4]], 'yellow_durations': []}, ['conflict:1-5', 'multi:1']), ({'channels': [[1, 'GY', True], [2, '', True], [3, '', True], [4, '', True], [5, '', True], [6, 'RY', True]], 'compat': [[4, 1], [1, 5], [4, 2], [6, 2]], 'yellow_durations': [[2, 35]]}, ['conflict:1-6', 'multi:1', 'multi:6', 'red-fail:2', 'red-fail:3', 'red-fail:4', 'red-fail:5'])], [({'channels': [[1, 'Y', True], [2, 'RG', True], [3, 'GY', True], [4, 'Y', True], [5, 'RG', True]], 'compat': [[1, 2], [4, 1], [5, 2], [3, 5]], 'yellow_durations': [[1, 26], [2, 27], [3, 25], [4, 27]]}, ['conflict:1-3', 'conflict:1-5', 'conflict:2-3', 'conflict:2-4', 'conflict:3-4', 'conflict:4-5', 'multi:2', 'multi:3', 'multi:5', 'short-yellow:1', 'short-yellow:3']), ({'channels': [[1, 'RY', True], [2, 'R', True], [3, 'RY', True], [4, '', True], [5, '', True], [6, 'RG', True]], 'compat': [[2, 1], [1, 3], [4, 1], [5, 1], [2, 3], [4, 2], [2, 5], [4, 3], [6, 4], [6, 5]], 'yellow_durations': [[2, 26]]}, ['conflict:1-6', 'conflict:3-6', 'multi:1', 'multi:3', 'multi:6', 'red-fail:4', 'red-fail:5', 'short-yellow:2']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'R', False], [2, '', True], [3, '', True], [4, 'RY', False], [5, 'RY', True]], 'compat': [[1, 4], [1, 5]], 'yellow_durations': [[1, 26], [2, 28], [4, 26]]}, ['multi:5', 'red-fail:2', 'red-fail:3', 'short-yellow:1', 'short-yellow:4']), ({'channels': [[1, 'GY', True], [2, 'RY', True], [3, 'G', True]], 'compat': [[3, 2]], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'conflict:1-3', 'multi:1', 'multi:2', 'short-yellow:1']), ({'channels': [[1, 'R', True], [2, 'Y', True], [3, 'GY', True], [4, 'R', True], [5, 'RY', False]], 'compat': [[2, 3], [4, 2], [2, 5], [4, 3]], 'yellow_durations': [[5, 35]]}, ['multi:3']), ({'channels': [[1, 'R', True], [2, 'RY', True], [3, 'GY', True]], 'compat': [[1, 2]], 'yellow_durations': [[3, 30]]}, ['conflict:2-3', 'multi:2', 'multi:3']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1'])], [({'channels': [[1, 'R', True], [2, 'R', True], [3, 'R', True]], 'compat': [], 'yellow_durations': [[3, 25]]}, ['short-yellow:3']), ({'channels': [[1, 'R', True], [2, 'RY', False], [3, 'R', True], [4, 'RG', True], [5, '', True]], 'compat': [[2, 3], [3, 4], [4, 5]], 'yellow_durations': [[1, 35], [2, 28], [3, 26], [4, 26], [5, 30]]}, ['multi:4', 'red-fail:5', 'short-yellow:3', 'short-yellow:4']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'RY', True], [2, 'RY', False], [3, 'RY', True], [4, 'RY', True]], 'compat': [[1, 2], [1, 4], [2, 3]], 'yellow_durations': [[1, 28], [3, 35]]}, ['conflict:1-3', 'conflict:3-4', 'multi:1', 'multi:3', 'multi:4']), ({'channels': [[1, 'R', False], [2, 'RY', True], [3, 'R', False], [4, 'GY', True], [5, 'GY', True], [6, 'R', True]], 'compat': [[3, 1], [5, 2], [6, 2], [3, 4], [5, 3], [4, 5]], 'yellow_durations': [[1, 25], [2, 28], [3, 27], [4, 28], [5, 35]]}, ['conflict:2-4', 'multi:2', 'multi:4', 'multi:5', 'short-yellow:1']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'Y', True], [2, '', True], [3, 'RY', True], [4, 'RG', True]], 'compat': [[2, 1], [3, 1], [1, 4], [4, 2]], 'yellow_durations': [[3, 26]]}, ['conflict:3-4', 'multi:3', 'multi:4', 'red-fail:2', 'short-yellow:3']), ({'channels': [[1, 'R', True], [2, '', True], [3, 'RG', True]], 'compat': [[1, 2], [1, 3]], 'yellow_durations': [[1, 30]]}, ['multi:3', 'red-fail:2'])], [({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'R', True], [2, 'R', True], [3, 'R', True]], 'compat': [], 'yellow_durations': [[1, 30]]}, []), ({'channels': [[1, 'R', True], [2, 'Y', True], [3, 'R', True]], 'compat': [[1, 2]], 'yellow_durations': [[1, 27], [2, 25], [3, 26]]}, ['short-yellow:2', 'short-yellow:3']), ({'channels': [[1, 'R', True], [2, '', True], [3, 'R', True], [4, 'RY', True]], 'compat': [[1, 3], [1, 4], [4, 2]], 'yellow_durations': [[3, 26]]}, ['multi:4', 'red-fail:2', 'short-yellow:3']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'Y', False], [2, 'RG', False], [3, 'R', True]], 'compat': [[3, 2]], 'yellow_durations': [[3, 26]]}, ['short-yellow:3']), ({'channels': [[1, 'RG', True], [2, 'RY', False], [3, 'RG', True], [4, 'R', True], [5, 'GY', True]], 'compat': [[1, 2], [4, 3], [5, 4]], 'yellow_durations': [[5, 27]]}, ['conflict:1-3', 'conflict:1-5', 'conflict:3-5', 'multi:1', 'multi:3', 'multi:5']), ({'channels': [[1, 'RY', False], [2, 'R', True], [3, 'RY', True], [4, 'R', True], [5, 'G', True], [6, 'G', True]], 'compat': [[1, 2], [5, 1], [6, 2], [3, 4], [5, 4], [6, 4]], 'yellow_durations': [[3, 25], [5, 25]]}, ['conflict:3-5', 'conflict:3-6', 'conflict:5-6', 'multi:3', 'short-yellow:3', 'short-yellow:5'])], [({'channels': [[1, 'Y', True], [2, 'R', True], [3, 'R', True], [4, '', True], [5, 'RY', True], [6, 'G', True]], 'compat': [[6, 1], [3, 4], [3, 6], [4, 6], [6, 5]], 'yellow_durations': [[3, 30]]}, ['conflict:1-5', 'multi:5', 'red-fail:4']), ({'channels': [[1, 'Y', True], [2, 'RG', False], [3, 'G', True], [4, 'RG', True], [5, 'RY', True]], 'compat': [[1, 2], [1, 4], [5, 1], [3, 2], [4, 2], [3, 5]], 'yellow_durations': [[1, 30]]}, ['conflict:1-3', 'conflict:3-4', 'conflict:4-5', 'multi:4', 'multi:5']), ({'channels': [[1, 'R', True], [2, 'R', True], [3, 'G', True], [4, 'GY', True]], 'compat': [[3, 2], [3, 4]], 'yellow_durations': [[4, 27]]}, ['multi:4']), ({'channels': [[1, 'G', True], [2, 'R', True], [3, 'Y', True], [4, 'G', False]], 'compat': [[3, 1]], 'yellow_durations': [[2, 27]]}, []), ({'channels': [[1, 'Y', True], [2, 'RG', False], [3, 'R', False], [4, 'GY', False], [5, 'RY', True]], 'compat': [[1, 2], [2, 4], [3, 4]], 'yellow_durations': [[3, 27]]}, ['conflict:1-5', 'multi:5']), ({'channels': [[1, 'R', True], [2, 'R', True], [3, 'GY', True]], 'compat': [[2, 1]], 'yellow_durations': [[2, 28]]}, ['multi:3']), ({'channels': [[1, 'GY', True], [2, 'G', True], [3, '', True]], 'compat': [], 'yellow_durations': [[1, 26]]}, ['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']), ({'channels': [[1, 'G', True], [2, 'RY', True], [3, 'R', True], [4, '', True]], 'compat': [[1, 2], [3, 1], [1, 4], [3, 4]], 'yellow_durations': [[3, 30]]}, ['multi:2', 'red-fail:4'])]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check('timing oracle' + ' %d' % i, 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
timing oracle 0['multi:5', 'red-fail:2']['multi:5', 'red-fail:2']Passed
timing oracle 1['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']['conflict:1-2', 'multi:1', 'red-fail:3', 'short-yellow:1']Passed
timing oracle 2['conflict:1-4', 'conflict:3-4'][]Failed
timing oracle 3[][]Passed
timing oracle 4['conflict:3-4', 'multi:1']['conflict:3-4']Failed
timing oracle 5['red-fail:2', 'short-yellow:5']['red-fail:2', 'short-yellow:5']Passed
timing oracle 6['conflict:1-5', 'conflict:4-5', 'multi:1', 'multi:4']['conflict:1-5', 'multi:1']Failed
timing oracle 7['conflict:1-6', 'multi:1', 'multi:6', 'red-fail:2', 'red-fail:3', 'red-fail:4', 'red-fail:5']['conflict:1-6', 'multi:1', 'multi:6', 'red-fail:2', 'red-fail:3', 'red-fail:4', 'red-fail:5']Passed

SHA-256 / bc32b36f7ab98414452ae15a8ca016655ff1dd92edd29b7dc8a863dbeddc8dc2

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 8 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.

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Verification & scope

A deterministic, bounded toy model with a stipulated contract; it makes no claim of conformance to any agency manual or standard. 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 2026-09-29T14:48:00.904640+00:00.

Case digest / 0bc8c64cefc38ba4a48e0fd63821bbcaed0971c21f186401ba3da857f6933830