FA-9551 / Version constraints / Open access

Compatible release admission: An exact pin is treated as advisory · case 01

An exact pin is treated as advisory.

Verified by executionVariant 1 · 25 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The implementation substitutes True for (pin is None or candidate == pin), so an exact pin is treated as advisory.

THE FAILURE

The implementation substitutes True for (pin is None or candidate == pin), so an exact pin is treated as advisory.

Unsuccessful approach: The attempted repair substitutes (pin is not None and candidate == pin). Fixture 6 still yields False instead of True.

Case contract

Accept candidate tuple if not excluded, at least the lower release, below the compatibility ceiling, and prerelease only when opted in; exact pins additionally require equality.

Why this case matters

An offline model of compatible release admission, suitable for testing build and release tooling without external services.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(candidate, low, ceiling, excluded, prerelease, allow_pre, pin):
    return (candidate not in excluded and candidate >= low and candidate < ceiling and (not prerelease or allow_pre) and True)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve((1, 1), (1, 2), (2, 0), [], False, False, None), False)
check('fixture 2', solve((1, 1), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 3', solve((1, 1), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 4', solve((1, 1), (1, 2), (2, 0), [], True, True, None), False)
check('fixture 5', solve((1, 1), (1, 2), (2, 0), [], False, False, (1, 2)), False)
check('fixture 6', solve((1, 2), (1, 2), (2, 0), [], False, False, None), True)
check('fixture 7', solve((1, 2), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 8', solve((1, 2), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 9', solve((1, 2), (1, 2), (2, 0), [], True, True, None), True)
check('fixture 10', solve((1, 2), (1, 2), (2, 0), [], False, False, (1, 2)), True)
check('fixture 11', solve((1, 9), (1, 2), (2, 0), [], False, False, None), True)
check('fixture 12', solve((1, 9), (1, 2), (2, 0), [(1, 2)], False, False, None), True)
check('fixture 13', solve((1, 9), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 14', solve((1, 9), (1, 2), (2, 0), [], True, True, None), True)
check('fixture 15', solve((1, 9), (1, 2), (2, 0), [], False, False, (1, 2)), False)
check('fixture 16', solve((2, 0), (1, 2), (2, 0), [], False, False, None), False)
check('fixture 17', solve((2, 0), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 18', solve((2, 0), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 19', solve((2, 0), (1, 2), (2, 0), [], True, True, None), False)
check('fixture 20', solve((2, 0), (1, 2), (2, 0), [], False, False, (1, 2)), False)
check('fixture 21', solve((2, 1), (1, 2), (2, 0), [], False, False, None), False)
check('fixture 22', solve((2, 1), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 23', solve((2, 1), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 24', solve((2, 1), (1, 2), (2, 0), [], True, True, None), False)
check('fixture 25', solve((2, 1), (1, 2), (2, 0), [], False, False, (1, 2)), False)
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 fixture	Actual	Expected	Outcome
fixture 1	`False`	`False`	Passed
fixture 2	`False`	`False`	Passed
fixture 3	`False`	`False`	Passed
fixture 4	`False`	`False`	Passed
fixture 5	`False`	`False`	Passed
fixture 6	`True`	`True`	Passed
fixture 7	`False`	`False`	Passed
fixture 8	`False`	`False`	Passed
fixture 9	`True`	`True`	Passed
fixture 10	`True`	`True`	Passed
fixture 11	`True`	`True`	Passed
fixture 12	`True`	`True`	Passed
fixture 13	`False`	`False`	Passed
fixture 14	`True`	`True`	Passed
fixture 15	`True`	`False`	Failed
fixture 16	`False`	`False`	Passed
fixture 17	`False`	`False`	Passed
fixture 18	`False`	`False`	Passed
fixture 19	`False`	`False`	Passed
fixture 20	`False`	`False`	Passed
fixture 21	`False`	`False`	Passed
fixture 22	`False`	`False`	Passed
fixture 23	`False`	`False`	Passed
fixture 24	`False`	`False`	Passed
fixture 25	`False`	`False`	Passed

SHA-256 / a3653a5999e099e54b04c0b43775233200d1ffbcb1b70fd6c6a0bbbaa5efcd97

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(candidate, low, ceiling, excluded, prerelease, allow_pre, pin):
    return (candidate not in excluded and candidate >= low and candidate < ceiling and (not prerelease or allow_pre) and (pin is not None and candidate == pin))
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve((1, 1), (1, 2), (2, 0), [], False, False, None), False)
check('fixture 2', solve((1, 1), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 3', solve((1, 1), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 4', solve((1, 1), (1, 2), (2, 0), [], True, True, None), False)
check('fixture 5', solve((1, 1), (1, 2), (2, 0), [], False, False, (1, 2)), False)
check('fixture 6', solve((1, 2), (1, 2), (2, 0), [], False, False, None), True)
check('fixture 7', solve((1, 2), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 8', solve((1, 2), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 9', solve((1, 2), (1, 2), (2, 0), [], True, True, None), True)
check('fixture 10', solve((1, 2), (1, 2), (2, 0), [], False, False, (1, 2)), True)
check('fixture 11', solve((1, 9), (1, 2), (2, 0), [], False, False, None), True)
check('fixture 12', solve((1, 9), (1, 2), (2, 0), [(1, 2)], False, False, None), True)
check('fixture 13', solve((1, 9), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 14', solve((1, 9), (1, 2), (2, 0), [], True, True, None), True)
check('fixture 15', solve((1, 9), (1, 2), (2, 0), [], False, False, (1, 2)), False)
check('fixture 16', solve((2, 0), (1, 2), (2, 0), [], False, False, None), False)
check('fixture 17', solve((2, 0), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 18', solve((2, 0), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 19', solve((2, 0), (1, 2), (2, 0), [], True, True, None), False)
check('fixture 20', solve((2, 0), (1, 2), (2, 0), [], False, False, (1, 2)), False)
check('fixture 21', solve((2, 1), (1, 2), (2, 0), [], False, False, None), False)
check('fixture 22', solve((2, 1), (1, 2), (2, 0), [(1, 2)], False, False, None), False)
check('fixture 23', solve((2, 1), (1, 2), (2, 0), [], True, False, None), False)
check('fixture 24', solve((2, 1), (1, 2), (2, 0), [], True, True, None), False)
check('fixture 25', solve((2, 1), (1, 2), (2, 0), [], False, False, (1, 2)), False)
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 fixture	Actual	Expected	Outcome
fixture 1	`False`	`False`	Passed
fixture 2	`False`	`False`	Passed
fixture 3	`False`	`False`	Passed
fixture 4	`False`	`False`	Passed
fixture 5	`False`	`False`	Passed
fixture 6	`False`	`True`	Failed
fixture 7	`False`	`False`	Passed
fixture 8	`False`	`False`	Passed
fixture 9	`False`	`True`	Failed
fixture 10	`True`	`True`	Passed
fixture 11	`False`	`True`	Failed
fixture 12	`False`	`True`	Failed
fixture 13	`False`	`False`	Passed
fixture 14	`False`	`True`	Failed
fixture 15	`False`	`False`	Passed
fixture 16	`False`	`False`	Passed
fixture 17	`False`	`False`	Passed
fixture 18	`False`	`False`	Passed
fixture 19	`False`	`False`	Passed
fixture 20	`False`	`False`	Passed
fixture 21	`False`	`False`	Passed
fixture 22	`False`	`False`	Passed
fixture 23	`False`	`False`	Passed
fixture 24	`False`	`False`	Passed
fixture 25	`False`	`False`	Passed

SHA-256 / 692b9340486b9917a35f36698496f666ed05c5f8299d3852a2a7a2388c63537a

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 25 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.

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Verification & scope

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 2026-09-29T14:38:30.989644+00:00.

Case digest / c734e3ecde81419dc4c4afe655dcd2ff8965fe05dec2387ba4ad409a62f78a46