FA-9716 / Configuration / Open access
Command option assignment: Unset stores a null instead of removing the setting · case 01
Unset stores a null instead of removing the setting.
ROOT CAUSE
The implementation substitutes elif op == 'unset': result[key] = None for elif op == 'unset': result.pop(key, None), so unset stores a null instead of removing the setting.
VERIFIED REPAIR
Delete the key, tolerating absence.
Unsuccessful approach: The attempted repair substitutes elif op == 'unset': pass. Fixture 4 still yields {'a': 1} instead of {}.
Case contract
Starting from defaults, process assignment, append, unset, enable, and disable operations in sequence. Append creates a new list or extends an existing list. Unknown operations are ignored.
Why this case matters
An offline model of command option assignment, 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(defaults, operations):
result = dict(defaults)
for op, key, value in operations:
if op == 'set': result[key] = value
elif op == 'append': result[key] = list(result.get(key, [])) + [value]
elif op == 'unset': result[key] = None
elif op == 'enable': result[key] = True
elif op == 'disable': result[key] = False
return result
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({}, []), {})
check('fixture 2', solve({'a': 1}, [('set', 'a', 0)]), {'a': 0})
check('fixture 3', solve({'a': [1]}, [('append', 'a', 2), ('append', 'a', 2)]), {'a': [1, 2, 2]})
check('fixture 4', solve({'a': 1}, [('unset', 'a', None)]), {})
check('fixture 5', solve({}, [('unset', 'a', None)]), {})
check('fixture 6', solve({}, [('enable', 'a', None)]), {'a': True})
check('fixture 7', solve({'a': True}, [('disable', 'a', None)]), {'a': False})
check('fixture 8', solve({'a': 1}, [('unknown', 'a', 2)]), {'a': 1})
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 | {} | {} | Passed |
| fixture 2 | {'a': 0} | {'a': 0} | Passed |
| fixture 3 | {'a': [1, 2, 2]} | {'a': [1, 2, 2]} | Passed |
| fixture 4 | {'a': None} | {} | Failed |
| fixture 5 | {'a': None} | {} | Failed |
| fixture 6 | {'a': True} | {'a': True} | Passed |
| fixture 7 | {'a': False} | {'a': False} | Passed |
| fixture 8 | {'a': 1} | {'a': 1} | Passed |
SHA-256 / dc1c1205a8ee817c5d168a33ccfc8b35c6006a97ab1784622f955f97856a4e8a
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(defaults, operations):
result = dict(defaults)
for op, key, value in operations:
if op == 'set': result[key] = value
elif op == 'append': result[key] = list(result.get(key, [])) + [value]
elif op == 'unset': pass
elif op == 'enable': result[key] = True
elif op == 'disable': result[key] = False
return result
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({}, []), {})
check('fixture 2', solve({'a': 1}, [('set', 'a', 0)]), {'a': 0})
check('fixture 3', solve({'a': [1]}, [('append', 'a', 2), ('append', 'a', 2)]), {'a': [1, 2, 2]})
check('fixture 4', solve({'a': 1}, [('unset', 'a', None)]), {})
check('fixture 5', solve({}, [('unset', 'a', None)]), {})
check('fixture 6', solve({}, [('enable', 'a', None)]), {'a': True})
check('fixture 7', solve({'a': True}, [('disable', 'a', None)]), {'a': False})
check('fixture 8', solve({'a': 1}, [('unknown', 'a', 2)]), {'a': 1})
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 | {} | {} | Passed |
| fixture 2 | {'a': 0} | {'a': 0} | Passed |
| fixture 3 | {'a': [1, 2, 2]} | {'a': [1, 2, 2]} | Passed |
| fixture 4 | {'a': 1} | {} | Failed |
| fixture 5 | {} | {} | Passed |
| fixture 6 | {'a': True} | {'a': True} | Passed |
| fixture 7 | {'a': False} | {'a': False} | Passed |
| fixture 8 | {'a': 1} | {'a': 1} | Passed |
SHA-256 / 77a279591d53804b2671a81036f2684a0b8f8e732e5c7d60fdaf512c797e59a8
3 / The verified repair
Exit 0"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(defaults, operations):
result = dict(defaults)
for op, key, value in operations:
if op == 'set': result[key] = value
elif op == 'append': result[key] = list(result.get(key, [])) + [value]
elif op == 'unset': result.pop(key, None)
elif op == 'enable': result[key] = True
elif op == 'disable': result[key] = False
return result
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({}, []), {})
check('fixture 2', solve({'a': 1}, [('set', 'a', 0)]), {'a': 0})
check('fixture 3', solve({'a': [1]}, [('append', 'a', 2), ('append', 'a', 2)]), {'a': [1, 2, 2]})
check('fixture 4', solve({'a': 1}, [('unset', 'a', None)]), {})
check('fixture 5', solve({}, [('unset', 'a', None)]), {})
check('fixture 6', solve({}, [('enable', 'a', None)]), {'a': True})
check('fixture 7', solve({'a': True}, [('disable', 'a', None)]), {'a': False})
check('fixture 8', solve({'a': 1}, [('unknown', 'a', 2)]), {'a': 1})
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 | {} | {} | Passed |
| fixture 2 | {'a': 0} | {'a': 0} | Passed |
| fixture 3 | {'a': [1, 2, 2]} | {'a': [1, 2, 2]} | Passed |
| fixture 4 | {} | {} | Passed |
| fixture 5 | {} | {} | Passed |
| fixture 6 | {'a': True} | {'a': True} | Passed |
| fixture 7 | {'a': False} | {'a': False} | Passed |
| fixture 8 | {'a': 1} | {'a': 1} | Passed |
SHA-256 / 5d7cfa8dc45bb88d9368df82e61291e5ac15ac80580a2061d6aaa6e5e5315274
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 2026-09-29T14:38:32.373517+00:00.
Case digest / 4f929229e684d4f74ace718d63eb4def0022478a2bfeacd27e6f420e49c75e0d