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FA-68461 / Toll and parking fee computation / Open access

Street meter time purchase: a new purchase ignores the remaining paid time · case 01

Street meter time purchase returns a wrong result when a new purchase ignores the remaining paid time.

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

ROOT CAUSE

Topping up restarts from now, discarding minutes already paid.

VERIFIED REPAIR

Restore the extension from expiry rule so that the step reads `max(base, x['expiry'])`.

Unsuccessful approach: Extending from a stale expiry in the past gives time that has already elapsed.

Case contract

Input {now, expiry (or null), paid_cents, rate_per_hour, max_minutes, enf_start, enf_end, increment}. Only whole increments are credited. At or after enforcement end nothing is sold: [null, 0]. Paid time starts at the later of now, enforcement start and any unexpired expiry; it ends at the earliest of start + purchased minutes (floor), max(now, enf_start) + max_minutes, and enf_end. Accepted cents = min(credited, ceil(used minutes * rate/60)). Return [new expiry, accepted cents].

Why this case matters

Fee engines bill customers in integer cents; a wrong boundary, rounding stage or cap scope silently over- or under-charges.

1 / The failure

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

N = 1
observations = []
def solve(x):
    inc = x['increment']
    c = x['paid_cents'] - x['paid_cents'] % inc
    now = x['now']
    if now >= x['enf_end']:
        return [None, 0]
    base = max(now, x['enf_start'])
    start = base if x['expiry'] is None else base
    mins = c * 60 // x['rate_per_hour']
    end = min(start + mins, base + x['max_minutes'], x['enf_end'])
    used = max(0, end - start)
    cost = min(c, -(-used * x['rate_per_hour'] // 60))
    return [max(end, start), cost]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[({'now': 480, 'expiry': 507, 'paid_cents': 386, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [657, 375]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 974, 'expiry': 1004, 'paid_cents': 53, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1024, 50]), ({'now': 1080, 'expiry': None, 'paid_cents': 482, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 502, 'expiry': 497, 'paid_cents': 193, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [554, 174]), ({'now': 9, 'expiry': 5, 'paid_cents': 311, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [600, 200]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200])], [({'now': 495, 'expiry': 548, 'paid_cents': 54, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [555, 30]), ({'now': 983, 'expiry': 1008, 'paid_cents': 521, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 240]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 480, 'expiry': None, 'paid_cents': 223, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [560, 200]), ({'now': 1008, 'expiry': 949, 'paid_cents': 513, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 240]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 480, 'expiry': 459, 'paid_cents': 336, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [540, 250]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200])], [({'now': 1080, 'expiry': 1031, 'paid_cents': 14, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 761, 'expiry': 757, 'paid_cents': 208, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [821, 150]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 645, 'expiry': 664, 'paid_cents': 14, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [670, 10]), ({'now': 597, 'expiry': 543, 'paid_cents': 14, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [601, 10]), ({'now': 812, 'expiry': 824, 'paid_cents': 149, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [872, 120]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234])], [({'now': 650, 'expiry': 663, 'paid_cents': 527, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [710, 79]), ({'now': 1040, 'expiry': None, 'paid_cents': 333, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1080, 100]), ({'now': 392, 'expiry': 350, 'paid_cents': 319, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [600, 300]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 61, 'expiry': 125, 'paid_cents': 66, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [492, 50]), ({'now': 480, 'expiry': 510, 'paid_cents': 581, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [720, 350]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 1080, 'expiry': 1072, 'paid_cents': 138, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0])], [({'now': 1040, 'expiry': None, 'paid_cents': 333, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1080, 100]), ({'now': 583, 'expiry': 530, 'paid_cents': 342, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [643, 100]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 480, 'expiry': 552, 'paid_cents': 342, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [552, 0]), ({'now': 480, 'expiry': 428, 'paid_cents': 263, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 496, 'expiry': 502, 'paid_cents': 61, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [516, 59]), ({'now': 934, 'expiry': 971, 'paid_cents': 344, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [994, 77])]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check('fee 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
fee oracle 0[630, 375][657, 375]Failed
fee oracle 1[None, 0][None, 0]Passed
fee oracle 2[994, 50][1024, 50]Failed
fee oracle 3[None, 0][None, 0]Passed
fee oracle 4[554, 174][554, 174]Passed
fee oracle 5[600, 200][600, 200]Passed
fee oracle 6[720, 400][720, 234]Failed
fee oracle 7[540, 200][540, 200]Passed

SHA-256 / e3c0e48b3b0b357cd7a997dec3a9e9225096468624414fb13789807bcdc1c5f1

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(x):
    inc = x['increment']
    c = x['paid_cents'] - x['paid_cents'] % inc
    now = x['now']
    if now >= x['enf_end']:
        return [None, 0]
    base = max(now, x['enf_start'])
    start = base if x['expiry'] is None else x['expiry']
    mins = c * 60 // x['rate_per_hour']
    end = min(start + mins, base + x['max_minutes'], x['enf_end'])
    used = max(0, end - start)
    cost = min(c, -(-used * x['rate_per_hour'] // 60))
    return [max(end, start), cost]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[({'now': 480, 'expiry': 507, 'paid_cents': 386, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [657, 375]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 974, 'expiry': 1004, 'paid_cents': 53, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1024, 50]), ({'now': 1080, 'expiry': None, 'paid_cents': 482, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 502, 'expiry': 497, 'paid_cents': 193, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [554, 174]), ({'now': 9, 'expiry': 5, 'paid_cents': 311, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [600, 200]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200])], [({'now': 495, 'expiry': 548, 'paid_cents': 54, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [555, 30]), ({'now': 983, 'expiry': 1008, 'paid_cents': 521, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 240]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 480, 'expiry': None, 'paid_cents': 223, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [560, 200]), ({'now': 1008, 'expiry': 949, 'paid_cents': 513, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 240]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 480, 'expiry': 459, 'paid_cents': 336, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [540, 250]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200])], [({'now': 1080, 'expiry': 1031, 'paid_cents': 14, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 761, 'expiry': 757, 'paid_cents': 208, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [821, 150]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 645, 'expiry': 664, 'paid_cents': 14, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [670, 10]), ({'now': 597, 'expiry': 543, 'paid_cents': 14, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [601, 10]), ({'now': 812, 'expiry': 824, 'paid_cents': 149, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [872, 120]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234])], [({'now': 650, 'expiry': 663, 'paid_cents': 527, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [710, 79]), ({'now': 1040, 'expiry': None, 'paid_cents': 333, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1080, 100]), ({'now': 392, 'expiry': 350, 'paid_cents': 319, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [600, 300]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 61, 'expiry': 125, 'paid_cents': 66, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [492, 50]), ({'now': 480, 'expiry': 510, 'paid_cents': 581, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [720, 350]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 1080, 'expiry': 1072, 'paid_cents': 138, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0])], [({'now': 1040, 'expiry': None, 'paid_cents': 333, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1080, 100]), ({'now': 583, 'expiry': 530, 'paid_cents': 342, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [643, 100]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 480, 'expiry': 552, 'paid_cents': 342, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [552, 0]), ({'now': 480, 'expiry': 428, 'paid_cents': 263, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 496, 'expiry': 502, 'paid_cents': 61, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [516, 59]), ({'now': 934, 'expiry': 971, 'paid_cents': 344, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [994, 77])]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check('fee 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
fee oracle 0[657, 375][657, 375]Passed
fee oracle 1[None, 0][None, 0]Passed
fee oracle 2[1024, 50][1024, 50]Passed
fee oracle 3[None, 0][None, 0]Passed
fee oracle 4[549, 174][554, 174]Failed
fee oracle 5[185, 300][600, 200]Failed
fee oracle 6[720, 234][720, 234]Passed
fee oracle 7[540, 200][540, 200]Passed

SHA-256 / 551dfe1a95098617f76a83e8341b8da4c361c1bdd9b37511964ac8afc6571f59

3 / The verified repair

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

N = 1
observations = []
def solve(x):
    inc = x['increment']
    c = x['paid_cents'] - x['paid_cents'] % inc
    now = x['now']
    if now >= x['enf_end']:
        return [None, 0]
    base = max(now, x['enf_start'])
    start = base if x['expiry'] is None else max(base, x['expiry'])
    mins = c * 60 // x['rate_per_hour']
    end = min(start + mins, base + x['max_minutes'], x['enf_end'])
    used = max(0, end - start)
    cost = min(c, -(-used * x['rate_per_hour'] // 60))
    return [max(end, start), cost]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[({'now': 480, 'expiry': 507, 'paid_cents': 386, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [657, 375]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 974, 'expiry': 1004, 'paid_cents': 53, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1024, 50]), ({'now': 1080, 'expiry': None, 'paid_cents': 482, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 502, 'expiry': 497, 'paid_cents': 193, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [554, 174]), ({'now': 9, 'expiry': 5, 'paid_cents': 311, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [600, 200]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200])], [({'now': 495, 'expiry': 548, 'paid_cents': 54, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [555, 30]), ({'now': 983, 'expiry': 1008, 'paid_cents': 521, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 240]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 480, 'expiry': None, 'paid_cents': 223, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [560, 200]), ({'now': 1008, 'expiry': 949, 'paid_cents': 513, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 240]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 480, 'expiry': 459, 'paid_cents': 336, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [540, 250]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200])], [({'now': 1080, 'expiry': 1031, 'paid_cents': 14, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 761, 'expiry': 757, 'paid_cents': 208, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [821, 150]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 645, 'expiry': 664, 'paid_cents': 14, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [670, 10]), ({'now': 597, 'expiry': 543, 'paid_cents': 14, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [601, 10]), ({'now': 812, 'expiry': 824, 'paid_cents': 149, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [872, 120]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234])], [({'now': 650, 'expiry': 663, 'paid_cents': 527, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [710, 79]), ({'now': 1040, 'expiry': None, 'paid_cents': 333, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1080, 100]), ({'now': 392, 'expiry': 350, 'paid_cents': 319, 'rate_per_hour': 150, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [600, 300]), ({'now': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 61, 'expiry': 125, 'paid_cents': 66, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [492, 50]), ({'now': 480, 'expiry': 510, 'paid_cents': 581, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [720, 350]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 1080, 'expiry': 1072, 'paid_cents': 138, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0])], [({'now': 1040, 'expiry': None, 'paid_cents': 333, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1080, 100]), ({'now': 583, 'expiry': 530, 'paid_cents': 342, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [643, 100]), ({'now': 1080, 'expiry': 1100, 'paid_cents': 100, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [None, 0]), ({'now': 480, 'expiry': 552, 'paid_cents': 342, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [552, 0]), ({'now': 480, 'expiry': 428, 'paid_cents': 263, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 420, 'expiry': None, 'paid_cents': 200, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [540, 200]), ({'now': 496, 'expiry': 502, 'paid_cents': 61, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [516, 59]), ({'now': 934, 'expiry': 971, 'paid_cents': 344, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [994, 77])]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check('fee 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
fee oracle 0[657, 375][657, 375]Passed
fee oracle 1[None, 0][None, 0]Passed
fee oracle 2[1024, 50][1024, 50]Passed
fee oracle 3[None, 0][None, 0]Passed
fee oracle 4[554, 174][554, 174]Passed
fee oracle 5[600, 200][600, 200]Passed
fee oracle 6[720, 234][720, 234]Passed
fee oracle 7[540, 200][540, 200]Passed

SHA-256 / f866f49d627f282ee8ca8c248df6d2e47ba015b6d55fd3bed27c38df0a68aef3

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 2026-09-29T14:48:02.440035+00:00.

Case digest / 392fc26184d96d98f9ca2df7076de56c03cbdc131b78dd080122157f4528691a