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FA-66821 / Airline fare rule evaluation / Open access

Commencement window applied to the return date · case 01

A trip that starts inside the travel window but returns after it fails COMMENCE.

Verified by executionVariant 1 · 10 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The commencement check reads the last travel date.

THE FAILURE

The commencement check reads the last travel date.

Unsuccessful approach: Requiring the whole trip inside the window turns the commencement rule into a completion rule.

Case contract

Input {'sale','first_travel','last_travel','sale_window','travel_window','complete_by'} ISO dates. Sale date within the inclusive sale window, first travel within the inclusive travel (commencement) window, last travel on or before complete_by. Return failures in order SALE, COMMENCE, COMPLETE.

Why this case matters

Promotional fares restrict the ticketing period, the period in which travel must commence and a separate completion deadline.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import datetime
N = 1
observations = []
def solve(x):
    p = datetime.date.fromisoformat
    fails = []
    s0, s1 = map(p, x['sale_window'])
    t0, t1 = map(p, x['travel_window'])
    if not (s0 <= p(x['sale']) <= s1): fails.append('SALE')
    if not (t0 <= p(x['last_travel']) <= t1): fails.append('COMMENCE')
    if p(x['last_travel']) > p(x['complete_by']): fails.append('COMPLETE')
    return fails
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-01', 'first_travel': '2027-05-28', 'last_travel': '2027-06-03'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-17'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-11', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-01', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-12-30', '2028-01-23'], 'travel_window': ['2028-01-04', '2028-01-30'], 'complete_by': '2028-02-15', 'sale': '2027-12-31', 'first_travel': '2028-02-08', 'last_travel': '2028-02-13'}, ['COMMENCE']], ['sampled case 2', {'sale_window': ['2027-07-14', '2027-09-01'], 'travel_window': ['2027-07-14', '2027-10-07'], 'complete_by': '2027-11-03', 'sale': '2027-08-26', 'first_travel': '2027-09-15', 'last_travel': '2027-09-27'}, []], ['sampled case 3', {'sale_window': ['2027-04-22', '2027-06-16'], 'travel_window': ['2027-05-05', '2027-07-12'], 'complete_by': '2027-08-03', 'sale': '2027-04-27', 'first_travel': '2027-05-03', 'last_travel': '2027-05-25'}, ['COMMENCE']]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-02', 'first_travel': '2027-05-28', 'last_travel': '2027-06-04'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-18'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-12', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-02', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-10-21', '2027-11-05'], 'travel_window': ['2027-12-14', '2028-01-23'], 'complete_by': '2028-02-15', 'sale': '2027-12-06', 'first_travel': '2028-02-16', 'last_travel': '2028-03-01'}, ['SALE', 'COMMENCE', 'COMPLETE']], ['sampled case 2', {'sale_window': ['2027-10-07', '2027-10-26'], 'travel_window': ['2027-11-12', '2028-01-03'], 'complete_by': '2028-01-19', 'sale': '2027-10-27', 'first_travel': '2027-11-02', 'last_travel': '2027-11-14'}, ['SALE', 'COMMENCE']], ['sampled case 3', {'sale_window': ['2027-03-11', '2027-04-21'], 'travel_window': ['2027-03-25', '2027-06-12'], 'complete_by': '2027-07-08', 'sale': '2027-05-11', 'first_travel': '2027-05-21', 'last_travel': '2027-06-05'}, ['SALE']]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-03', 'first_travel': '2027-05-28', 'last_travel': '2027-06-05'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-16'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-13', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-03', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-06-20', '2027-08-16'], 'travel_window': ['2027-08-18', '2027-09-23'], 'complete_by': '2027-10-09', 'sale': '2027-06-25', 'first_travel': '2027-11-23', 'last_travel': '2027-12-19'}, ['COMMENCE', 'COMPLETE']], ['sampled case 2', {'sale_window': ['2027-06-05', '2027-07-18'], 'travel_window': ['2027-07-17', '2027-09-14'], 'complete_by': '2027-10-08', 'sale': '2027-07-17', 'first_travel': '2027-09-21', 'last_travel': '2027-09-26'}, ['COMMENCE']], ['sampled case 3', {'sale_window': ['2027-10-11', '2027-11-28'], 'travel_window': ['2027-11-28', '2028-01-22'], 'complete_by': '2028-02-08', 'sale': '2027-11-06', 'first_travel': '2027-12-31', 'last_travel': '2028-01-29'}, []]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-04', 'first_travel': '2027-05-28', 'last_travel': '2027-06-06'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-17'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-14', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-04', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-05-07', '2027-05-28'], 'travel_window': ['2027-06-09', '2027-08-31'], 'complete_by': '2027-09-16', 'sale': '2027-06-01', 'first_travel': '2027-06-02', 'last_travel': '2027-06-03'}, ['SALE', 'COMMENCE']], ['sampled case 2', {'sale_window': ['2027-10-02', '2027-11-17'], 'travel_window': ['2027-10-11', '2027-12-26'], 'complete_by': '2028-01-09', 'sale': '2027-12-04', 'first_travel': '2027-12-02', 'last_travel': '2027-12-23'}, ['SALE']], ['sampled case 3', {'sale_window': ['2027-05-15', '2027-06-12'], 'travel_window': ['2027-06-29', '2027-07-19'], 'complete_by': '2027-07-30', 'sale': '2027-07-16', 'first_travel': '2027-10-06', 'last_travel': '2027-10-22'}, ['SALE', 'COMMENCE', 'COMPLETE']]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-05', 'first_travel': '2027-05-28', 'last_travel': '2027-06-07'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-18'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-15', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-05', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-07-10', '2027-07-30'], 'travel_window': ['2027-08-12', '2027-11-08'], 'complete_by': '2027-11-08', 'sale': '2027-08-17', 'first_travel': '2027-09-03', 'last_travel': '2027-09-06'}, ['SALE']], ['sampled case 2', {'sale_window': ['2027-02-23', '2027-03-25'], 'travel_window': ['2027-03-20', '2027-05-01'], 'complete_by': '2027-05-16', 'sale': '2027-03-25', 'first_travel': '2027-04-25', 'last_travel': '2027-05-04'}, []], ['sampled case 3', {'sale_window': ['2027-01-05', '2027-01-22'], 'travel_window': ['2027-01-19', '2027-02-25'], 'complete_by': '2027-03-09', 'sale': '2027-01-17', 'first_travel': '2027-01-17', 'last_travel': '2027-01-31'}, ['COMMENCE']]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
trip finishing after commence window['COMMENCE'][]Failed
sold on last sale day[][]Passed
completes exactly on deadline['COMMENCE'][]Failed
completes a day late['COMMENCE', 'COMPLETE']['COMPLETE']Failed
sold before travel window opens[][]Passed
commences too late['COMMENCE']['COMMENCE']Passed
sold too early['SALE']['SALE']Passed
sampled case 1['COMMENCE']['COMMENCE']Passed
sampled case 2[][]Passed
sampled case 3[]['COMMENCE']Failed

SHA-256 / 80fcd3954b51c5e08ce99e0f7f468642e2c2660f7e81b9479d686828ca3fcf1c

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import datetime
N = 1
observations = []
def solve(x):
    p = datetime.date.fromisoformat
    fails = []
    s0, s1 = map(p, x['sale_window'])
    t0, t1 = map(p, x['travel_window'])
    if not (s0 <= p(x['sale']) <= s1): fails.append('SALE')
    if not (t0 <= p(x['first_travel']) and p(x['last_travel']) <= t1): fails.append('COMMENCE')
    if p(x['last_travel']) > p(x['complete_by']): fails.append('COMPLETE')
    return fails
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-01', 'first_travel': '2027-05-28', 'last_travel': '2027-06-03'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-17'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-11', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-01', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-12-30', '2028-01-23'], 'travel_window': ['2028-01-04', '2028-01-30'], 'complete_by': '2028-02-15', 'sale': '2027-12-31', 'first_travel': '2028-02-08', 'last_travel': '2028-02-13'}, ['COMMENCE']], ['sampled case 2', {'sale_window': ['2027-07-14', '2027-09-01'], 'travel_window': ['2027-07-14', '2027-10-07'], 'complete_by': '2027-11-03', 'sale': '2027-08-26', 'first_travel': '2027-09-15', 'last_travel': '2027-09-27'}, []], ['sampled case 3', {'sale_window': ['2027-04-22', '2027-06-16'], 'travel_window': ['2027-05-05', '2027-07-12'], 'complete_by': '2027-08-03', 'sale': '2027-04-27', 'first_travel': '2027-05-03', 'last_travel': '2027-05-25'}, ['COMMENCE']]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-02', 'first_travel': '2027-05-28', 'last_travel': '2027-06-04'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-18'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-12', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-02', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-10-21', '2027-11-05'], 'travel_window': ['2027-12-14', '2028-01-23'], 'complete_by': '2028-02-15', 'sale': '2027-12-06', 'first_travel': '2028-02-16', 'last_travel': '2028-03-01'}, ['SALE', 'COMMENCE', 'COMPLETE']], ['sampled case 2', {'sale_window': ['2027-10-07', '2027-10-26'], 'travel_window': ['2027-11-12', '2028-01-03'], 'complete_by': '2028-01-19', 'sale': '2027-10-27', 'first_travel': '2027-11-02', 'last_travel': '2027-11-14'}, ['SALE', 'COMMENCE']], ['sampled case 3', {'sale_window': ['2027-03-11', '2027-04-21'], 'travel_window': ['2027-03-25', '2027-06-12'], 'complete_by': '2027-07-08', 'sale': '2027-05-11', 'first_travel': '2027-05-21', 'last_travel': '2027-06-05'}, ['SALE']]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-03', 'first_travel': '2027-05-28', 'last_travel': '2027-06-05'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-16'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-13', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-03', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-06-20', '2027-08-16'], 'travel_window': ['2027-08-18', '2027-09-23'], 'complete_by': '2027-10-09', 'sale': '2027-06-25', 'first_travel': '2027-11-23', 'last_travel': '2027-12-19'}, ['COMMENCE', 'COMPLETE']], ['sampled case 2', {'sale_window': ['2027-06-05', '2027-07-18'], 'travel_window': ['2027-07-17', '2027-09-14'], 'complete_by': '2027-10-08', 'sale': '2027-07-17', 'first_travel': '2027-09-21', 'last_travel': '2027-09-26'}, ['COMMENCE']], ['sampled case 3', {'sale_window': ['2027-10-11', '2027-11-28'], 'travel_window': ['2027-11-28', '2028-01-22'], 'complete_by': '2028-02-08', 'sale': '2027-11-06', 'first_travel': '2027-12-31', 'last_travel': '2028-01-29'}, []]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-04', 'first_travel': '2027-05-28', 'last_travel': '2027-06-06'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-17'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-14', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-04', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-05-07', '2027-05-28'], 'travel_window': ['2027-06-09', '2027-08-31'], 'complete_by': '2027-09-16', 'sale': '2027-06-01', 'first_travel': '2027-06-02', 'last_travel': '2027-06-03'}, ['SALE', 'COMMENCE']], ['sampled case 2', {'sale_window': ['2027-10-02', '2027-11-17'], 'travel_window': ['2027-10-11', '2027-12-26'], 'complete_by': '2028-01-09', 'sale': '2027-12-04', 'first_travel': '2027-12-02', 'last_travel': '2027-12-23'}, ['SALE']], ['sampled case 3', {'sale_window': ['2027-05-15', '2027-06-12'], 'travel_window': ['2027-06-29', '2027-07-19'], 'complete_by': '2027-07-30', 'sale': '2027-07-16', 'first_travel': '2027-10-06', 'last_travel': '2027-10-22'}, ['SALE', 'COMMENCE', 'COMPLETE']]], [['trip finishing after commence window', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-05', 'first_travel': '2027-05-28', 'last_travel': '2027-06-07'}, []], ['sold on last sale day', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-28', 'first_travel': '2027-03-10', 'last_travel': '2027-03-17'}, []], ['completes exactly on deadline', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-01', 'last_travel': '2027-06-15'}, []], ['completes a day late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-20', 'first_travel': '2027-05-20', 'last_travel': '2027-06-18'}, ['COMPLETE']], ['sold before travel window opens', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-15', 'first_travel': '2027-03-01', 'last_travel': '2027-03-05'}, []], ['commences too late', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-02-10', 'first_travel': '2027-06-05', 'last_travel': '2027-06-10'}, ['COMMENCE']], ['sold too early', {'sale_window': ['2027-01-10', '2027-02-28'], 'travel_window': ['2027-03-01', '2027-05-31'], 'complete_by': '2027-06-15', 'sale': '2027-01-09', 'first_travel': '2027-04-01', 'last_travel': '2027-04-08'}, ['SALE']], ['sampled case 1', {'sale_window': ['2027-07-10', '2027-07-30'], 'travel_window': ['2027-08-12', '2027-11-08'], 'complete_by': '2027-11-08', 'sale': '2027-08-17', 'first_travel': '2027-09-03', 'last_travel': '2027-09-06'}, ['SALE']], ['sampled case 2', {'sale_window': ['2027-02-23', '2027-03-25'], 'travel_window': ['2027-03-20', '2027-05-01'], 'complete_by': '2027-05-16', 'sale': '2027-03-25', 'first_travel': '2027-04-25', 'last_travel': '2027-05-04'}, []], ['sampled case 3', {'sale_window': ['2027-01-05', '2027-01-22'], 'travel_window': ['2027-01-19', '2027-02-25'], 'complete_by': '2027-03-09', 'sale': '2027-01-17', 'first_travel': '2027-01-17', 'last_travel': '2027-01-31'}, ['COMMENCE']]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
trip finishing after commence window['COMMENCE'][]Failed
sold on last sale day[][]Passed
completes exactly on deadline['COMMENCE'][]Failed
completes a day late['COMMENCE', 'COMPLETE']['COMPLETE']Failed
sold before travel window opens[][]Passed
commences too late['COMMENCE']['COMMENCE']Passed
sold too early['SALE']['SALE']Passed
sampled case 1['COMMENCE']['COMMENCE']Passed
sampled case 2[][]Passed
sampled case 3['COMMENCE']['COMMENCE']Passed

SHA-256 / 48b2de41d53673c4724f2aa0bff8b2175540e97d696137a6edd3dec2b5435ead

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 10 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.

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Verification & scope

A stipulated toy fare-rule contract with invented constants; it is not an ATPCO or carrier tariff implementation and makes no claim of industry-standard conformance. 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 2026-09-29T14:47:47.407952+00:00.

Case digest / ac270156e9214ebf4d373c5d4297a3ab478ac34e939c899e7ef216d8c9926089