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FA-68456 / Toll and parking fee computation / Open access

Street meter time purchase: time bought before enforcement starts immediately · case 01

Street meter time purchase returns a wrong result when time bought before enforcement starts immediately.

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

ROOT CAUSE

Paid minutes are consumed during free hours before enforcement begins.

VERIFIED REPAIR

Restore the purchase before enforcement rule so that the step reads `base = max(now, x['enf_start'])`.

Unsuccessful approach: Deferring only fresh purchases still lets extensions before enforcement burn paid time.

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 = now
    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': 459, 'expiry': None, 'paid_cents': 517, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 400]), ({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'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': 479, 'expiry': None, 'paid_cents': 114, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [524, 110]), ({'now': 427, 'expiry': 476, 'paid_cents': 417, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [600, 300]), ({'now': 1004, 'expiry': None, 'paid_cents': 562, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 127]), ({'now': 414, 'expiry': 388, 'paid_cents': 65, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [495, 50])], [({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 81, 'expiry': 101, 'paid_cents': 151, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [516, 150]), ({'now': 480, 'expiry': None, 'paid_cents': 99, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [498, 75]), ({'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': 1061, 'paid_cents': 149, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 65, 'expiry': 152, 'paid_cents': 24, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [480, 0]), ({'now': 480, 'expiry': 502, 'paid_cents': 468, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [600, 327])], [({'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': 449, 'expiry': None, 'paid_cents': 279, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [546, 275]), ({'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': 1056, 'paid_cents': 124, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 441, 'expiry': 437, 'paid_cents': 475, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [720, 400]), ({'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': 1177, 'expiry': None, 'paid_cents': 418, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 327, 'expiry': 289, 'paid_cents': 186, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [532, 174])], [({'now': 751, 'expiry': None, 'paid_cents': 37, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [759, 34]), ({'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': 420, 'expiry': 426, 'paid_cents': 444, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [582, 425]), ({'now': 1080, 'expiry': 1101, 'paid_cents': 444, 'rate_per_hour': 150, 'max_minutes': 120, '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': 402, 'expiry': 435, 'paid_cents': 29, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [490, 25]), ({'now': 1001, 'expiry': 1047, 'paid_cents': 331, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1061, 59]), ({'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': 1060, 'expiry': 1107, 'paid_cents': 414, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1107, 0]), ({'now': 47, 'expiry': 84, 'paid_cents': 192, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [537, 190]), ({'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': 147, 'expiry': 118, 'paid_cents': 14, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [480, 0]), ({'now': 862, 'expiry': 851, 'paid_cents': 76, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [884, 74]), ({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 45, 'expiry': None, 'paid_cents': 260, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [542, 259])]]
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[699, 400][720, 400]Failed
fee oracle 1[None, 0][None, 0]Passed
fee oracle 2[720, 234][720, 234]Passed
fee oracle 3[1080, 100][1080, 100]Passed
fee oracle 4[523, 110][524, 110]Failed
fee oracle 5[547, 178][600, 300]Failed
fee oracle 6[1080, 127][1080, 127]Passed
fee oracle 7[429, 50][495, 50]Failed

SHA-256 / 51146abb7d9caa72067f4f285178518b550d18472d190428efd8383a62e8b07c

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']) if x['expiry'] is None else now
    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': 459, 'expiry': None, 'paid_cents': 517, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 400]), ({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'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': 479, 'expiry': None, 'paid_cents': 114, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [524, 110]), ({'now': 427, 'expiry': 476, 'paid_cents': 417, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [600, 300]), ({'now': 1004, 'expiry': None, 'paid_cents': 562, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 127]), ({'now': 414, 'expiry': 388, 'paid_cents': 65, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [495, 50])], [({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 81, 'expiry': 101, 'paid_cents': 151, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [516, 150]), ({'now': 480, 'expiry': None, 'paid_cents': 99, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [498, 75]), ({'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': 1061, 'paid_cents': 149, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 65, 'expiry': 152, 'paid_cents': 24, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [480, 0]), ({'now': 480, 'expiry': 502, 'paid_cents': 468, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [600, 327])], [({'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': 449, 'expiry': None, 'paid_cents': 279, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [546, 275]), ({'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': 1056, 'paid_cents': 124, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 441, 'expiry': 437, 'paid_cents': 475, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [720, 400]), ({'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': 1177, 'expiry': None, 'paid_cents': 418, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 327, 'expiry': 289, 'paid_cents': 186, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [532, 174])], [({'now': 751, 'expiry': None, 'paid_cents': 37, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [759, 34]), ({'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': 420, 'expiry': 426, 'paid_cents': 444, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [582, 425]), ({'now': 1080, 'expiry': 1101, 'paid_cents': 444, 'rate_per_hour': 150, 'max_minutes': 120, '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': 402, 'expiry': 435, 'paid_cents': 29, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [490, 25]), ({'now': 1001, 'expiry': 1047, 'paid_cents': 331, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1061, 59]), ({'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': 1060, 'expiry': 1107, 'paid_cents': 414, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1107, 0]), ({'now': 47, 'expiry': 84, 'paid_cents': 192, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [537, 190]), ({'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': 147, 'expiry': 118, 'paid_cents': 14, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [480, 0]), ({'now': 862, 'expiry': 851, 'paid_cents': 76, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [884, 74]), ({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 45, 'expiry': None, 'paid_cents': 260, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [542, 259])]]
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[720, 400][720, 400]Passed
fee oracle 1[None, 0][None, 0]Passed
fee oracle 2[720, 234][720, 234]Passed
fee oracle 3[1080, 100][1080, 100]Passed
fee oracle 4[524, 110][524, 110]Passed
fee oracle 5[547, 178][600, 300]Failed
fee oracle 6[1080, 127][1080, 127]Passed
fee oracle 7[429, 50][495, 50]Failed

SHA-256 / 900f4f15cc21dd024bf9db9571d39b7ec70108355fac5a4e9e517958553c87b4

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': 459, 'expiry': None, 'paid_cents': 517, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 400]), ({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'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': 479, 'expiry': None, 'paid_cents': 114, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [524, 110]), ({'now': 427, 'expiry': 476, 'paid_cents': 417, 'rate_per_hour': 150, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [600, 300]), ({'now': 1004, 'expiry': None, 'paid_cents': 562, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [1080, 127]), ({'now': 414, 'expiry': 388, 'paid_cents': 65, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [495, 50])], [({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 81, 'expiry': 101, 'paid_cents': 151, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [516, 150]), ({'now': 480, 'expiry': None, 'paid_cents': 99, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [498, 75]), ({'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': 1061, 'paid_cents': 149, 'rate_per_hour': 100, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 65, 'expiry': 152, 'paid_cents': 24, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [480, 0]), ({'now': 480, 'expiry': 502, 'paid_cents': 468, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [600, 327])], [({'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': 449, 'expiry': None, 'paid_cents': 279, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [546, 275]), ({'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': 1056, 'paid_cents': 124, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 441, 'expiry': 437, 'paid_cents': 475, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [720, 400]), ({'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': 1177, 'expiry': None, 'paid_cents': 418, 'rate_per_hour': 100, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [None, 0]), ({'now': 327, 'expiry': 289, 'paid_cents': 186, 'rate_per_hour': 200, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [532, 174])], [({'now': 751, 'expiry': None, 'paid_cents': 37, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [759, 34]), ({'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': 420, 'expiry': 426, 'paid_cents': 444, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [582, 425]), ({'now': 1080, 'expiry': 1101, 'paid_cents': 444, 'rate_per_hour': 150, 'max_minutes': 120, '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': 402, 'expiry': 435, 'paid_cents': 29, 'rate_per_hour': 150, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [490, 25]), ({'now': 1001, 'expiry': 1047, 'paid_cents': 331, 'rate_per_hour': 250, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1061, 59]), ({'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': 1060, 'expiry': 1107, 'paid_cents': 414, 'rate_per_hour': 100, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [1107, 0]), ({'now': 47, 'expiry': 84, 'paid_cents': 192, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [537, 190]), ({'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': 147, 'expiry': 118, 'paid_cents': 14, 'rate_per_hour': 250, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [480, 0]), ({'now': 862, 'expiry': 851, 'paid_cents': 76, 'rate_per_hour': 200, 'max_minutes': 60, 'enf_start': 480, 'enf_end': 1080, 'increment': 25}, [884, 74]), ({'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': 600, 'expiry': 650, 'paid_cents': 400, 'rate_per_hour': 200, 'max_minutes': 120, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [720, 234]), ({'now': 45, 'expiry': None, 'paid_cents': 260, 'rate_per_hour': 250, 'max_minutes': 240, 'enf_start': 480, 'enf_end': 1080, 'increment': 5}, [542, 259])]]
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[720, 400][720, 400]Passed
fee oracle 1[None, 0][None, 0]Passed
fee oracle 2[720, 234][720, 234]Passed
fee oracle 3[1080, 100][1080, 100]Passed
fee oracle 4[524, 110][524, 110]Passed
fee oracle 5[600, 300][600, 300]Passed
fee oracle 6[1080, 127][1080, 127]Passed
fee oracle 7[495, 50][495, 50]Passed

SHA-256 / 25a3d864525c1c67cbdb78ffb8834e3607196d1a3815ce0e68c8b1c4e78501a5

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 2026-09-29T14:48:02.345079+00:00.

Case digest / ffd33b2000d042cb0a52959c303a75bbb5a2087641f7c4a4c81c553434d83011