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FA-93156 / EV charging session scheduling / Open access

Weekly recurring charging windows: overnight tail day selection · case 01

Friday-night windows do not continue into Saturday morning, but Saturday mornings open when only Saturday night is scheduled.

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

ROOT CAUSE

The after-midnight portion checks the current day bit instead of the start day bit.

VERIFIED REPAIR

Check the previous day bit for the after-midnight tail.

Unsuccessful approach: Accepting either day still opens tails that no rule started.

Case contract

rules are [day_mask, start, end] with bit 0 = Monday .. bit 6 = Sunday. start < end is a same-day window [start, end); start == end means the whole selected day; start > end crosses midnight and belongs to its start day (Sunday continues into Monday). Return the sorted indices of rules allowing charging at (day 0..6, minute 0..1439).

Why this case matters

Depot, workplace and public EV chargers schedule sessions against prices, circuit limits and departure deadlines; a wrong decision silently strands a driver or overloads a feeder.

1 / The failure

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

N = 1
observations = []
def solve(rules, day, minute):
    hits = []
    for i, (mask, s, e) in enumerate(rules):
        today = mask >> day & 1
        yday = mask >> (day - 1) % 7 & 1
        if s == e:
            if today:
                hits.append(i)
        elif s < e:
            if today and s <= minute < e:
                hits.append(i)
        elif (today and minute >= s) or (today and minute < e):
            hits.append(i)
    return hits
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[72, 0, 1380], [114, 1380, 1080], [82, 1320, 60], [68, 1080, 1380]], 0, 900], [1]],
  ['regression: overnight tail day selection (partial repair)',
   [[[5, 1320, 420], [82, 1080, 1320], [98, 1380, 1380]], 0, 61], []],
  ['control 1', [[[75, 1380, 360]], 0, 1379], []],
  ['control 2', [[[26, 1380, 420], [118, 360, 0], [104, 1080, 1080]], 3, 0], [2]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[113, 360, 60], [87, 420, 0], [65, 1380, 1380], [90, 1380, 1320]], 5, 420], [0, 3]],
  ['regression: overnight tail day selection (partial repair)', [[[19, 1380, 1080]], 0, 61], []],
  ['control 1', [[[18, 60, 0], [118, 1080, 0], [124, 60, 360], [93, 1080, 60]], 4, 0], [3]],
  ['control 2', [[[28, 1320, 1080], [123, 420, 1380], [9, 1380, 0]], 6, 359], []]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[7, 0, 0], [6, 360, 1380], [33, 1080, 420], [76, 0, 1080]], 6, 59], [2, 3]],
  ['regression: overnight tail day selection (partial repair)',
   [[[60, 420, 60], [112, 1080, 420]], 2, 0], []],
  ['control 1', [[[103, 0, 360], [65, 360, 1380], [37, 1080, 1080]], 4, 60], []],
  ['control 2', [[[52, 420, 1320], [97, 1080, 360]], 0, 0], [1]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[124, 0, 0], [53, 1320, 360], [89, 60, 60]], 4, 30], [0, 2]],
  ['regression: overnight tail day selection (partial repair)',
   [[[40, 1320, 1080], [75, 1380, 360], [72, 1320, 1080], [75, 360, 1080]], 6, 61], [0]],
  ['control 1', [[[105, 420, 360], [31, 1380, 1320], [47, 1080, 1320]], 4, 60], [0, 1]],
  ['control 2', [[[59, 360, 60], [45, 420, 60]], 5, 360], [0]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection', [[[51, 360, 1080], [116, 1320, 420]], 0, 60], [1]],
  ['regression: overnight tail day selection (partial repair)',
   [[[95, 420, 60], [9, 1320, 1080]], 3, 900], [0]],
  ['control 1', [[[51, 360, 60], [78, 1080, 1080], [25, 1320, 360], [11, 360, 0]], 2, 1380], [1]],
  ['control 2', [[[16, 1380, 0]], 1, 360], []]]]
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
boundary: Monday morning after Sunday night window[][0]Failed
boundary: same-day window end minute[][]Passed
boundary: whole-day rule[0][0]Passed
regression: overnight tail day selection[][1]Failed
regression: overnight tail day selection (partial repair)[0][]Failed
control 1[][]Passed
control 2[0, 2][2]Failed

SHA-256 / 820b3978795cf2086c171e2e90d6b9c40c748770a8cb33222a6ed193ec62181a

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(rules, day, minute):
    hits = []
    for i, (mask, s, e) in enumerate(rules):
        today = mask >> day & 1
        yday = mask >> (day - 1) % 7 & 1
        if s == e:
            if today:
                hits.append(i)
        elif s < e:
            if today and s <= minute < e:
                hits.append(i)
        elif (today and minute >= s) or ((yday or today) and minute < e):
            hits.append(i)
    return hits
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[72, 0, 1380], [114, 1380, 1080], [82, 1320, 60], [68, 1080, 1380]], 0, 900], [1]],
  ['regression: overnight tail day selection (partial repair)',
   [[[5, 1320, 420], [82, 1080, 1320], [98, 1380, 1380]], 0, 61], []],
  ['control 1', [[[75, 1380, 360]], 0, 1379], []],
  ['control 2', [[[26, 1380, 420], [118, 360, 0], [104, 1080, 1080]], 3, 0], [2]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[113, 360, 60], [87, 420, 0], [65, 1380, 1380], [90, 1380, 1320]], 5, 420], [0, 3]],
  ['regression: overnight tail day selection (partial repair)', [[[19, 1380, 1080]], 0, 61], []],
  ['control 1', [[[18, 60, 0], [118, 1080, 0], [124, 60, 360], [93, 1080, 60]], 4, 0], [3]],
  ['control 2', [[[28, 1320, 1080], [123, 420, 1380], [9, 1380, 0]], 6, 359], []]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[7, 0, 0], [6, 360, 1380], [33, 1080, 420], [76, 0, 1080]], 6, 59], [2, 3]],
  ['regression: overnight tail day selection (partial repair)',
   [[[60, 420, 60], [112, 1080, 420]], 2, 0], []],
  ['control 1', [[[103, 0, 360], [65, 360, 1380], [37, 1080, 1080]], 4, 60], []],
  ['control 2', [[[52, 420, 1320], [97, 1080, 360]], 0, 0], [1]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[124, 0, 0], [53, 1320, 360], [89, 60, 60]], 4, 30], [0, 2]],
  ['regression: overnight tail day selection (partial repair)',
   [[[40, 1320, 1080], [75, 1380, 360], [72, 1320, 1080], [75, 360, 1080]], 6, 61], [0]],
  ['control 1', [[[105, 420, 360], [31, 1380, 1320], [47, 1080, 1320]], 4, 60], [0, 1]],
  ['control 2', [[[59, 360, 60], [45, 420, 60]], 5, 360], [0]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection', [[[51, 360, 1080], [116, 1320, 420]], 0, 60], [1]],
  ['regression: overnight tail day selection (partial repair)',
   [[[95, 420, 60], [9, 1320, 1080]], 3, 900], [0]],
  ['control 1', [[[51, 360, 60], [78, 1080, 1080], [25, 1320, 360], [11, 360, 0]], 2, 1380], [1]],
  ['control 2', [[[16, 1380, 0]], 1, 360], []]]]
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
boundary: Monday morning after Sunday night window[0][0]Passed
boundary: same-day window end minute[][]Passed
boundary: whole-day rule[0][0]Passed
regression: overnight tail day selection[1][1]Passed
regression: overnight tail day selection (partial repair)[0][]Failed
control 1[][]Passed
control 2[0, 2][2]Failed

SHA-256 / b21a536c7b40913b63678749d247d7458401ecae0bdad15ead0b4fb6994a4570

3 / The verified repair

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

N = 1
observations = []
def solve(rules, day, minute):
    hits = []
    for i, (mask, s, e) in enumerate(rules):
        today = mask >> day & 1
        yday = mask >> (day - 1) % 7 & 1
        if s == e:
            if today:
                hits.append(i)
        elif s < e:
            if today and s <= minute < e:
                hits.append(i)
        elif (today and minute >= s) or (yday and minute < e):
            hits.append(i)
    return hits
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[72, 0, 1380], [114, 1380, 1080], [82, 1320, 60], [68, 1080, 1380]], 0, 900], [1]],
  ['regression: overnight tail day selection (partial repair)',
   [[[5, 1320, 420], [82, 1080, 1320], [98, 1380, 1380]], 0, 61], []],
  ['control 1', [[[75, 1380, 360]], 0, 1379], []],
  ['control 2', [[[26, 1380, 420], [118, 360, 0], [104, 1080, 1080]], 3, 0], [2]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[113, 360, 60], [87, 420, 0], [65, 1380, 1380], [90, 1380, 1320]], 5, 420], [0, 3]],
  ['regression: overnight tail day selection (partial repair)', [[[19, 1380, 1080]], 0, 61], []],
  ['control 1', [[[18, 60, 0], [118, 1080, 0], [124, 60, 360], [93, 1080, 60]], 4, 0], [3]],
  ['control 2', [[[28, 1320, 1080], [123, 420, 1380], [9, 1380, 0]], 6, 359], []]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[7, 0, 0], [6, 360, 1380], [33, 1080, 420], [76, 0, 1080]], 6, 59], [2, 3]],
  ['regression: overnight tail day selection (partial repair)',
   [[[60, 420, 60], [112, 1080, 420]], 2, 0], []],
  ['control 1', [[[103, 0, 360], [65, 360, 1380], [37, 1080, 1080]], 4, 60], []],
  ['control 2', [[[52, 420, 1320], [97, 1080, 360]], 0, 0], [1]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection',
   [[[124, 0, 0], [53, 1320, 360], [89, 60, 60]], 4, 30], [0, 2]],
  ['regression: overnight tail day selection (partial repair)',
   [[[40, 1320, 1080], [75, 1380, 360], [72, 1320, 1080], [75, 360, 1080]], 6, 61], [0]],
  ['control 1', [[[105, 420, 360], [31, 1380, 1320], [47, 1080, 1320]], 4, 60], [0, 1]],
  ['control 2', [[[59, 360, 60], [45, 420, 60]], 5, 360], [0]]],
 [['boundary: Monday morning after Sunday night window', [[[64, 1320, 360]], 0, 100], [0]],
  ['boundary: same-day window end minute', [[[127, 60, 360]], 3, 360], []],
  ['boundary: whole-day rule', [[[4, 420, 420]], 2, 5], [0]],
  ['regression: overnight tail day selection', [[[51, 360, 1080], [116, 1320, 420]], 0, 60], [1]],
  ['regression: overnight tail day selection (partial repair)',
   [[[95, 420, 60], [9, 1320, 1080]], 3, 900], [0]],
  ['control 1', [[[51, 360, 60], [78, 1080, 1080], [25, 1320, 360], [11, 360, 0]], 2, 1380], [1]],
  ['control 2', [[[16, 1380, 0]], 1, 360], []]]]
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
boundary: Monday morning after Sunday night window[0][0]Passed
boundary: same-day window end minute[][]Passed
boundary: whole-day rule[0][0]Passed
regression: overnight tail day selection[1][1]Passed
regression: overnight tail day selection (partial repair)[][]Passed
control 1[][]Passed
control 2[2][2]Passed

SHA-256 / 41cd6a06fa566ed8afe6bb78fdb9894346ed8eeaabcc2c80ac19a527e63a1ac0

Verification & scope

Deterministic stipulated toy contract for teaching; no claim of conformance with any standard, vendor protocol or production controller. 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 2026-09-29T14:51:52.513865+00:00.

Case digest / 56a04453b4c9a078e6c70513a07609c47d77f2c4ed0442aaf8b800e38c311504