FAILURE MAP
← Case archive

FA-93986 / Shift rostering labor rules / Open access

Consecutive-day streak ignores days worked before the roster period · case 01

A worker finishing six straight days last period can be rostered for more days immediately.

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

ROOT CAUSE

The streak counter starts at zero instead of the carried-in count.

THE FAILURE

The streak counter starts at zero instead of the carried-in count.

Unsuccessful approach: Treating any carry-in as a single day still undercounts longer streaks.

Case contract

A day pattern (W worked, O rostered off, L leave) and the count of consecutive worked days immediately before it. Any worked day that makes the streak exceed six is a streak violation; O or L ends a streak. Every 14-day window fully inside the pattern (each start index) needs at least two O days; leave does not count as a rostered day off. Return [kind, index] rows: streaks in day order, then windows.

Why this case matters

Consecutive-day limits and fortnightly day-off minimums are standard roster labor rules.

1 / The failure

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

N = 1
observations = []
def solve(pattern, carry_in):
    out = []
    run = 0
    for i, c in enumerate(pattern):
        if c == 'W':
            run += 1
            if run > 6:
                out.append(['streak', i])
        else:
            run = 0
    for i in range(len(pattern) - 13):
        if pattern[i:i + 14].count('O') < 2:
            out.append(['rest14', i])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: streak carry in 1', ['WWWWLWWWWWWWWWWWWOLOL', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 11], ['streak', 12], ['streak', 13],
    ['streak', 14], ['streak', 15], ['streak', 16], ['rest14', 0], ['rest14', 1], ['rest14', 2],
    ['rest14', 3], ['rest14', 4], ['rest14', 5]]),
  ('regression variant: streak carry in 2', ['WWWWWOWWWLWLOWLWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4]]),
  ('partial repair guard 3', ['WWLLWWWLOWWWWWLWOW', 5],
   [['streak', 1], ['rest14', 0], ['rest14', 1], ['rest14', 2]]),
  ('boundary control 4', ['WWWWWWOWWWWWWOW', 0], []),
  ('boundary control 5', ['WWWWWWWO', 0], [['streak', 6]]),
  ('normal control 6', ['WLLWWLLLWWWOOWLWWO', 5], []), ('normal control 7', ['WWOWWWOWWLWWWW', 0], []),
  ('normal control 8', ['WWWWLWWWWLWOOWWWWW', 3], [['streak', 3]])],
 [('regression: streak carry in 1', ['WWLWWWWLWOOLWW', 5], [['streak', 1]]),
  ('regression variant: streak carry in 2', ['WWWWWWWWWWWWOOWOWWOWWWWWWWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5], ['streak', 6], ['streak', 7],
    ['streak', 8], ['streak', 9], ['streak', 10], ['streak', 11], ['streak', 25], ['streak', 26],
    ['streak', 27]]),
  ('partial repair guard 3', ['WOWWWWWWLOWLWWW', 6], [['streak', 0]]),
  ('boundary control 4', ['WWWLWWWWWWWOWWWO', 0], [['streak', 10], ['rest14', 0], ['rest14', 1]]),
  ('boundary control 5', ['WWWWWWOWWWWWWL', 0], [['rest14', 0]]),
  ('normal control 6', ['LOWWOWWWWWWWLW', 0], [['streak', 11]]),
  ('normal control 7', ['LWWWWWWWWLWWWL', 3], [['streak', 7], ['streak', 8], ['rest14', 0]]),
  ('normal control 8', ['LLWLOLWWOWWWOWWWWW', 0], [])],
 [('regression: streak carry in 1', ['WWWWOWWWOLOWOOWLWWWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3]]),
  ('regression variant: streak carry in 2', ['WWWWWWLOWWWWOOLWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5]]),
  ('partial repair guard 3', ['WWWWWWWWWWWWOOWOWWOWWWWWWWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5], ['streak', 6], ['streak', 7],
    ['streak', 8], ['streak', 9], ['streak', 10], ['streak', 11], ['streak', 25], ['streak', 26],
    ['streak', 27]]),
  ('boundary control 4', ['WWOWWWWWW', 3], []), ('boundary control 5', ['WWWWWWO', 0], []),
  ('normal control 6', ['LWLWWOWOWWWLWW', 1], []),
  ('normal control 7', ['OOOWWWWWWWWOWWL', 1], [['streak', 9], ['streak', 10]]),
  ('normal control 8', ['OWWWWWWLWOWLWW', 1], [])],
 [('regression: streak carry in 1', ['WOWWWWWWWWOWWWWWWWWOWWWWWWLW', 6],
   [['streak', 0], ['streak', 8], ['streak', 9], ['streak', 17], ['streak', 18], ['rest14', 2], ['rest14', 3],
    ['rest14', 4], ['rest14', 5], ['rest14', 11], ['rest14', 12], ['rest14', 13], ['rest14', 14]]),
  ('regression variant: streak carry in 2', ['WWWWOOWWOWOWWOLWWLWWW', 3], [['streak', 3]]),
  ('partial repair guard 3', ['WWWWLWWWWLWOOWWWWW', 3], [['streak', 3]]),
  ('boundary control 4', ['OWWWWWWOWWWWWW', 0], []), ('boundary control 5', ['WWWWWWOWWWWWWOW', 0], []),
  ('normal control 6', ['WWWWWWWWWLOWOL', 0], [['streak', 6], ['streak', 7], ['streak', 8]]),
  ('normal control 7', ['WWWWLWLLWWWOWOWWLWWWW', 6],
   [['streak', 0], ['streak', 1], ['streak', 2], ['streak', 3]]),
  ('normal control 8', ['WWWLWWOOWOLWWW', 1], [])],
 [('regression: streak carry in 1', ['WWWWWWWLWLWWWO', 1], [['streak', 5], ['streak', 6], ['rest14', 0]]),
  ('regression variant: streak carry in 2', ['WLOWWWWWWWWWWLWWWWWOWOLWWWWW', 6],
   [['streak', 0], ['streak', 9], ['streak', 10], ['streak', 11], ['streak', 12], ['rest14', 0],
    ['rest14', 1], ['rest14', 2], ['rest14', 3], ['rest14', 4], ['rest14', 5], ['rest14', 6],
    ['rest14', 7]]),
  ('partial repair guard 3', ['WWWWWWWWWLWWLWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5], ['streak', 6], ['streak', 7],
    ['streak', 8], ['rest14', 0], ['rest14', 1]]),
  ('boundary control 4', ['WWWWWWWO', 0], [['streak', 6]]),
  ('boundary control 5', ['WWWLWWWWWWWOWWWO', 0], [['streak', 10], ['rest14', 0], ['rest14', 1]]),
  ('normal control 6', ['WOWWWWWWWWWOWWWWWW', 5],
   [['streak', 8], ['streak', 9], ['streak', 10], ['rest14', 2], ['rest14', 3], ['rest14', 4]]),
  ('normal control 7', ['WWWWWOWWWLWLOWLWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4]]),
  ('normal control 8', ['WWWWWWWWLWWWWWW', 0], [['streak', 6], ['streak', 7], ['rest14', 0], ['rest14', 1]])]]
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
regression: streak carry in 1[['streak', 11], ['streak', 12], ['streak', 13], ['streak', 14], ['streak', 15], ['streak', 16], ['rest14', 0], ['rest14', 1], ['rest14', 2], ['rest14', 3], ['rest14', 4], ['rest14', 5]][['streak', 1], ['streak', 2], ['streak', 3], ['streak', 11], ['streak', 12], ['streak', 13], ['streak', 14], ['streak', 15], ['streak', 16], ['rest14', 0], ['rest14', 1], ['rest14', 2], ['rest14', 3], ['rest14', 4], ['rest14', 5]]Failed
regression variant: streak carry in 2[][['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4]]Failed
partial repair guard 3[['rest14', 0], ['rest14', 1], ['rest14', 2]][['streak', 1], ['rest14', 0], ['rest14', 1], ['rest14', 2]]Failed
boundary control 4[][]Passed
boundary control 5[['streak', 6]][['streak', 6]]Passed
normal control 6[][]Passed
normal control 7[][]Passed
normal control 8[][['streak', 3]]Failed

SHA-256 / 29fd0bb8fa4e00302b15c83c39dae54dd735ffdd92b2f1b6525ffb4bc5a9adc9

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(pattern, carry_in):
    out = []
    run = 1 if carry_in else 0
    for i, c in enumerate(pattern):
        if c == 'W':
            run += 1
            if run > 6:
                out.append(['streak', i])
        else:
            run = 0
    for i in range(len(pattern) - 13):
        if pattern[i:i + 14].count('O') < 2:
            out.append(['rest14', i])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: streak carry in 1', ['WWWWLWWWWWWWWWWWWOLOL', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 11], ['streak', 12], ['streak', 13],
    ['streak', 14], ['streak', 15], ['streak', 16], ['rest14', 0], ['rest14', 1], ['rest14', 2],
    ['rest14', 3], ['rest14', 4], ['rest14', 5]]),
  ('regression variant: streak carry in 2', ['WWWWWOWWWLWLOWLWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4]]),
  ('partial repair guard 3', ['WWLLWWWLOWWWWWLWOW', 5],
   [['streak', 1], ['rest14', 0], ['rest14', 1], ['rest14', 2]]),
  ('boundary control 4', ['WWWWWWOWWWWWWOW', 0], []),
  ('boundary control 5', ['WWWWWWWO', 0], [['streak', 6]]),
  ('normal control 6', ['WLLWWLLLWWWOOWLWWO', 5], []), ('normal control 7', ['WWOWWWOWWLWWWW', 0], []),
  ('normal control 8', ['WWWWLWWWWLWOOWWWWW', 3], [['streak', 3]])],
 [('regression: streak carry in 1', ['WWLWWWWLWOOLWW', 5], [['streak', 1]]),
  ('regression variant: streak carry in 2', ['WWWWWWWWWWWWOOWOWWOWWWWWWWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5], ['streak', 6], ['streak', 7],
    ['streak', 8], ['streak', 9], ['streak', 10], ['streak', 11], ['streak', 25], ['streak', 26],
    ['streak', 27]]),
  ('partial repair guard 3', ['WOWWWWWWLOWLWWW', 6], [['streak', 0]]),
  ('boundary control 4', ['WWWLWWWWWWWOWWWO', 0], [['streak', 10], ['rest14', 0], ['rest14', 1]]),
  ('boundary control 5', ['WWWWWWOWWWWWWL', 0], [['rest14', 0]]),
  ('normal control 6', ['LOWWOWWWWWWWLW', 0], [['streak', 11]]),
  ('normal control 7', ['LWWWWWWWWLWWWL', 3], [['streak', 7], ['streak', 8], ['rest14', 0]]),
  ('normal control 8', ['LLWLOLWWOWWWOWWWWW', 0], [])],
 [('regression: streak carry in 1', ['WWWWOWWWOLOWOOWLWWWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3]]),
  ('regression variant: streak carry in 2', ['WWWWWWLOWWWWOOLWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5]]),
  ('partial repair guard 3', ['WWWWWWWWWWWWOOWOWWOWWWWWWWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5], ['streak', 6], ['streak', 7],
    ['streak', 8], ['streak', 9], ['streak', 10], ['streak', 11], ['streak', 25], ['streak', 26],
    ['streak', 27]]),
  ('boundary control 4', ['WWOWWWWWW', 3], []), ('boundary control 5', ['WWWWWWO', 0], []),
  ('normal control 6', ['LWLWWOWOWWWLWW', 1], []),
  ('normal control 7', ['OOOWWWWWWWWOWWL', 1], [['streak', 9], ['streak', 10]]),
  ('normal control 8', ['OWWWWWWLWOWLWW', 1], [])],
 [('regression: streak carry in 1', ['WOWWWWWWWWOWWWWWWWWOWWWWWWLW', 6],
   [['streak', 0], ['streak', 8], ['streak', 9], ['streak', 17], ['streak', 18], ['rest14', 2], ['rest14', 3],
    ['rest14', 4], ['rest14', 5], ['rest14', 11], ['rest14', 12], ['rest14', 13], ['rest14', 14]]),
  ('regression variant: streak carry in 2', ['WWWWOOWWOWOWWOLWWLWWW', 3], [['streak', 3]]),
  ('partial repair guard 3', ['WWWWLWWWWLWOOWWWWW', 3], [['streak', 3]]),
  ('boundary control 4', ['OWWWWWWOWWWWWW', 0], []), ('boundary control 5', ['WWWWWWOWWWWWWOW', 0], []),
  ('normal control 6', ['WWWWWWWWWLOWOL', 0], [['streak', 6], ['streak', 7], ['streak', 8]]),
  ('normal control 7', ['WWWWLWLLWWWOWOWWLWWWW', 6],
   [['streak', 0], ['streak', 1], ['streak', 2], ['streak', 3]]),
  ('normal control 8', ['WWWLWWOOWOLWWW', 1], [])],
 [('regression: streak carry in 1', ['WWWWWWWLWLWWWO', 1], [['streak', 5], ['streak', 6], ['rest14', 0]]),
  ('regression variant: streak carry in 2', ['WLOWWWWWWWWWWLWWWWWOWOLWWWWW', 6],
   [['streak', 0], ['streak', 9], ['streak', 10], ['streak', 11], ['streak', 12], ['rest14', 0],
    ['rest14', 1], ['rest14', 2], ['rest14', 3], ['rest14', 4], ['rest14', 5], ['rest14', 6],
    ['rest14', 7]]),
  ('partial repair guard 3', ['WWWWWWWWWLWWLWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4], ['streak', 5], ['streak', 6], ['streak', 7],
    ['streak', 8], ['rest14', 0], ['rest14', 1]]),
  ('boundary control 4', ['WWWWWWWO', 0], [['streak', 6]]),
  ('boundary control 5', ['WWWLWWWWWWWOWWWO', 0], [['streak', 10], ['rest14', 0], ['rest14', 1]]),
  ('normal control 6', ['WOWWWWWWWWWOWWWWWW', 5],
   [['streak', 8], ['streak', 9], ['streak', 10], ['rest14', 2], ['rest14', 3], ['rest14', 4]]),
  ('normal control 7', ['WWWWWOWWWLWLOWLWWW', 5],
   [['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4]]),
  ('normal control 8', ['WWWWWWWWLWWWWWW', 0], [['streak', 6], ['streak', 7], ['rest14', 0], ['rest14', 1]])]]
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
regression: streak carry in 1[['streak', 11], ['streak', 12], ['streak', 13], ['streak', 14], ['streak', 15], ['streak', 16], ['rest14', 0], ['rest14', 1], ['rest14', 2], ['rest14', 3], ['rest14', 4], ['rest14', 5]][['streak', 1], ['streak', 2], ['streak', 3], ['streak', 11], ['streak', 12], ['streak', 13], ['streak', 14], ['streak', 15], ['streak', 16], ['rest14', 0], ['rest14', 1], ['rest14', 2], ['rest14', 3], ['rest14', 4], ['rest14', 5]]Failed
regression variant: streak carry in 2[][['streak', 1], ['streak', 2], ['streak', 3], ['streak', 4]]Failed
partial repair guard 3[['rest14', 0], ['rest14', 1], ['rest14', 2]][['streak', 1], ['rest14', 0], ['rest14', 1], ['rest14', 2]]Failed
boundary control 4[][]Passed
boundary control 5[['streak', 6]][['streak', 6]]Passed
normal control 6[][]Passed
normal control 7[][]Passed
normal control 8[][['streak', 3]]Failed

SHA-256 / 9d55cc60eef4e6e7433d29ff299d50ec94cc328ed8a0121c85903bdde361df62

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 8 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Sign in to the archive ↗

Verification & scope

Stipulated toy labor rule for a bounded roster model; it is not legal advice and does not claim conformance with any jurisdiction, award, or collective agreement. 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 2026-09-29T14:52:00.121397+00:00.

Case digest / e1ce64ffce0549869a198d79dac3741d4e9bf29066cc286b25e695924552bbd6