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FA-9696 / Configuration / Open access

Configuration change plan: Unchanged restart-sensitive keys trigger restart · case 01

Unchanged restart-sensitive keys trigger restart.

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

ROOT CAUSE

The implementation substitutes set(restart) for (added | removed | changed) & set(restart), so unchanged restart-sensitive keys trigger restart.

THE FAILURE

The implementation substitutes set(restart) for (added | removed | changed) & set(restart), so unchanged restart-sensitive keys trigger restart.

Unsuccessful approach: The attempted repair substitutes changed & set(restart). Fixture 2 still yields {'added': ['a'], 'removed': [], 'changed': [], 'restart': [], 'unchanged': []} instead of {'added': ['a'], 'removed': [], 'changed': [], 'restart': ['a'], 'unchanged': []}.

Case contract

Produce sorted added, removed, changed, restart-required, and unchanged key lists. Restart applies only to added/removed/changed keys in the restart set.

Why this case matters

An offline model of configuration change plan, 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(before, after, restart):
    added = set(after) - set(before)
    removed = set(before) - set(after)
    common = set(before) & set(after)
    changed = {k for k in common if before[k] != after[k]}
    return {'added': sorted(added), 'removed': sorted(removed), 'changed': sorted(changed), 'restart': sorted(set(restart)), 'unchanged': sorted(common - changed)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({}, {}, []), {'added': [], 'removed': [], 'changed': [], 'restart': [], 'unchanged': []})
check('fixture 2', solve({}, {'a': 1}, ['a']), {'added': ['a'], 'removed': [], 'changed': [], 'restart': ['a'], 'unchanged': []})
check('fixture 3', solve({'a': 1}, {}, ['a']), {'added': [], 'removed': ['a'], 'changed': [], 'restart': ['a'], 'unchanged': []})
check('fixture 4', solve({'a': 1}, {'a': 2}, ['a']), {'added': [], 'removed': [], 'changed': ['a'], 'restart': ['a'], 'unchanged': []})
check('fixture 5', solve({'a': 1}, {'a': 1}, ['a']), {'added': [], 'removed': [], 'changed': [], 'restart': [], 'unchanged': ['a']})
check('fixture 6', solve({'a': 1}, {'a': 2}, []), {'added': [], 'removed': [], 'changed': ['a'], 'restart': [], 'unchanged': []})
check('fixture 7', solve({'a': 1, 'b': 2}, {'a': 1, 'c': 3}, ['b', 'c']), {'added': ['c'], 'removed': ['b'], 'changed': [], 'restart': ['b', 'c'], 'unchanged': ['a']})
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
fixture 1{'added': [], 'changed': [], 'removed': [], 'restart': [], 'unchanged': []}{'added': [], 'changed': [], 'removed': [], 'restart': [], 'unchanged': []}Passed
fixture 2{'added': ['a'], 'changed': [], 'removed': [], 'restart': ['a'], 'unchanged': []}{'added': ['a'], 'changed': [], 'removed': [], 'restart': ['a'], 'unchanged': []}Passed
fixture 3{'added': [], 'changed': [], 'removed': ['a'], 'restart': ['a'], 'unchanged': []}{'added': [], 'changed': [], 'removed': ['a'], 'restart': ['a'], 'unchanged': []}Passed
fixture 4{'added': [], 'changed': ['a'], 'removed': [], 'restart': ['a'], 'unchanged': []}{'added': [], 'changed': ['a'], 'removed': [], 'restart': ['a'], 'unchanged': []}Passed
fixture 5{'added': [], 'changed': [], 'removed': [], 'restart': ['a'], 'unchanged': ['a']}{'added': [], 'changed': [], 'removed': [], 'restart': [], 'unchanged': ['a']}Failed
fixture 6{'added': [], 'changed': ['a'], 'removed': [], 'restart': [], 'unchanged': []}{'added': [], 'changed': ['a'], 'removed': [], 'restart': [], 'unchanged': []}Passed
fixture 7{'added': ['c'], 'changed': [], 'removed': ['b'], 'restart': ['b', 'c'], 'unchanged': ['a']}{'added': ['c'], 'changed': [], 'removed': ['b'], 'restart': ['b', 'c'], 'unchanged': ['a']}Passed

SHA-256 / 2108791ec246e76d3eb7dbef9ace1df773f93285a032cbcf47b8514e8e236ed5

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(before, after, restart):
    added = set(after) - set(before)
    removed = set(before) - set(after)
    common = set(before) & set(after)
    changed = {k for k in common if before[k] != after[k]}
    return {'added': sorted(added), 'removed': sorted(removed), 'changed': sorted(changed), 'restart': sorted(changed & set(restart)), 'unchanged': sorted(common - changed)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({}, {}, []), {'added': [], 'removed': [], 'changed': [], 'restart': [], 'unchanged': []})
check('fixture 2', solve({}, {'a': 1}, ['a']), {'added': ['a'], 'removed': [], 'changed': [], 'restart': ['a'], 'unchanged': []})
check('fixture 3', solve({'a': 1}, {}, ['a']), {'added': [], 'removed': ['a'], 'changed': [], 'restart': ['a'], 'unchanged': []})
check('fixture 4', solve({'a': 1}, {'a': 2}, ['a']), {'added': [], 'removed': [], 'changed': ['a'], 'restart': ['a'], 'unchanged': []})
check('fixture 5', solve({'a': 1}, {'a': 1}, ['a']), {'added': [], 'removed': [], 'changed': [], 'restart': [], 'unchanged': ['a']})
check('fixture 6', solve({'a': 1}, {'a': 2}, []), {'added': [], 'removed': [], 'changed': ['a'], 'restart': [], 'unchanged': []})
check('fixture 7', solve({'a': 1, 'b': 2}, {'a': 1, 'c': 3}, ['b', 'c']), {'added': ['c'], 'removed': ['b'], 'changed': [], 'restart': ['b', 'c'], 'unchanged': ['a']})
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
fixture 1{'added': [], 'changed': [], 'removed': [], 'restart': [], 'unchanged': []}{'added': [], 'changed': [], 'removed': [], 'restart': [], 'unchanged': []}Passed
fixture 2{'added': ['a'], 'changed': [], 'removed': [], 'restart': [], 'unchanged': []}{'added': ['a'], 'changed': [], 'removed': [], 'restart': ['a'], 'unchanged': []}Failed
fixture 3{'added': [], 'changed': [], 'removed': ['a'], 'restart': [], 'unchanged': []}{'added': [], 'changed': [], 'removed': ['a'], 'restart': ['a'], 'unchanged': []}Failed
fixture 4{'added': [], 'changed': ['a'], 'removed': [], 'restart': ['a'], 'unchanged': []}{'added': [], 'changed': ['a'], 'removed': [], 'restart': ['a'], 'unchanged': []}Passed
fixture 5{'added': [], 'changed': [], 'removed': [], 'restart': [], 'unchanged': ['a']}{'added': [], 'changed': [], 'removed': [], 'restart': [], 'unchanged': ['a']}Passed
fixture 6{'added': [], 'changed': ['a'], 'removed': [], 'restart': [], 'unchanged': []}{'added': [], 'changed': ['a'], 'removed': [], 'restart': [], 'unchanged': []}Passed
fixture 7{'added': ['c'], 'changed': [], 'removed': ['b'], 'restart': [], 'unchanged': ['a']}{'added': ['c'], 'changed': [], 'removed': ['b'], 'restart': ['b', 'c'], 'unchanged': ['a']}Failed

SHA-256 / 4918c21fbc147bce60bf3b25980874939eaa77d5a9ed44a17e1144de438ae55d

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 7 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

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 2026-09-29T14:38:32.260579+00:00.

Case digest / 4f4adb72ce13c8d9c5262d6f12bce180eb1d9f60fbc7ada63ce0f2f24a8b4f21