FA-9746 / Configuration / Open access

Deprecated option alias migration: Deprecated keys remain in the migrated configuration · case 01

Deprecated keys remain in the migrated configuration.

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

ROOT CAUSE

The implementation substitutes pass for result.pop(alias, None), so deprecated keys remain in the migrated configuration.

THE FAILURE

The implementation substitutes pass for result.pop(alias, None), so deprecated keys remain in the migrated configuration.

Unsuccessful approach: The attempted repair substitutes result.pop(canonical, None). Fixture 2 still yields ({'old': 1}, []) instead of ({'new': 1}, []).

Case contract

Copy canonical values; map alias values only when canonical is absent, remove alias keys, preserve unrelated options, and report conflicts where alias and canonical differ.

Why this case matters

An offline model of deprecated option alias migration, 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(config, aliases):
    result = dict(config)
    conflicts = []
    for alias, canonical in aliases.items():
        if alias not in config: continue
        if canonical in config and config[canonical] != config[alias]: conflicts.append(canonical)
        if canonical not in config: result[canonical] = config[alias]
        pass
    return (result, sorted(set(conflicts)))
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({}, {}), ({}, []))
check('fixture 2', solve({'old': 1}, {'old': 'new'}), ({'new': 1}, []))
check('fixture 3', solve({'old': 1, 'new': 2}, {'old': 'new'}), ({'new': 2}, ['new']))
check('fixture 4', solve({'old': 1, 'new': 1}, {'old': 'new'}), ({'new': 1}, []))
check('fixture 5', solve({'x': 3}, {'old': 'new'}), ({'x': 3}, []))
check('fixture 6', solve({'old': False}, {'old': 'new'}), ({'new': False}, []))
check('fixture 7', solve({'a': 1, 'b': 2, 'new': 3}, {'a': 'new', 'b': 'new'}), ({'new': 3}, ['new']))
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	`[{'new': 1, 'old': 1}, []]`	`[{'new': 1}, []]`	Failed
fixture 3	`[{'new': 2, 'old': 1}, ['new']]`	`[{'new': 2}, ['new']]`	Failed
fixture 4	`[{'new': 1, 'old': 1}, []]`	`[{'new': 1}, []]`	Failed
fixture 5	`[{'x': 3}, []]`	`[{'x': 3}, []]`	Passed
fixture 6	`[{'new': False, 'old': False}, []]`	`[{'new': False}, []]`	Failed
fixture 7	`[{'a': 1, 'b': 2, 'new': 3}, ['new']]`	`[{'new': 3}, ['new']]`	Failed

SHA-256 / c49a142348192a88053844f427067177e711c369cc5135441b304cbe46c02099

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(config, aliases):
    result = dict(config)
    conflicts = []
    for alias, canonical in aliases.items():
        if alias not in config: continue
        if canonical in config and config[canonical] != config[alias]: conflicts.append(canonical)
        if canonical not in config: result[canonical] = config[alias]
        result.pop(canonical, None)
    return (result, sorted(set(conflicts)))
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('fixture 1', solve({}, {}), ({}, []))
check('fixture 2', solve({'old': 1}, {'old': 'new'}), ({'new': 1}, []))
check('fixture 3', solve({'old': 1, 'new': 2}, {'old': 'new'}), ({'new': 2}, ['new']))
check('fixture 4', solve({'old': 1, 'new': 1}, {'old': 'new'}), ({'new': 1}, []))
check('fixture 5', solve({'x': 3}, {'old': 'new'}), ({'x': 3}, []))
check('fixture 6', solve({'old': False}, {'old': 'new'}), ({'new': False}, []))
check('fixture 7', solve({'a': 1, 'b': 2, 'new': 3}, {'a': 'new', 'b': 'new'}), ({'new': 3}, ['new']))
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	`[{'old': 1}, []]`	`[{'new': 1}, []]`	Failed
fixture 3	`[{'old': 1}, ['new']]`	`[{'new': 2}, ['new']]`	Failed
fixture 4	`[{'old': 1}, []]`	`[{'new': 1}, []]`	Failed
fixture 5	`[{'x': 3}, []]`	`[{'x': 3}, []]`	Passed
fixture 6	`[{'old': False}, []]`	`[{'new': False}, []]`	Failed
fixture 7	`[{'a': 1, 'b': 2}, ['new']]`	`[{'new': 3}, ['new']]`	Failed

SHA-256 / b66687a0a7edbe961a95e9e72a061ad0622749dd6e09e3b849a5fc4f0f503990

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.

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 2026-09-29T14:38:32.781237+00:00.

Case digest / 9b9edee382503ed89c36daf2dbf642f151c28e578d69106bd46b9cc094d495ec