FA-33051 / Menu interactions / Open access

Recent menu capacity retains oldest entries instead of newest · case 01

Recent menu capacity retains oldest entries instead of newest.

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

ROOT CAUSE

The recent-command-menu model applies `p['history'][-p['limit']:]` at its limit operation instead of the stipulated transformation.

THE FAILURE

The recent-command-menu model applies `p['history'][-p['limit']:]` at its limit operation instead of the stipulated transformation.

Unsuccessful approach: The attempted repair `p['history'][:p['limit']+1]` still violates the limit oracle.

Case contract

Recent command menus key history by command and context, rank by descending last-use time with use-count tie break, and exclude retired commands from presentation.

Why this case matters

Cascading and context menus require coherent command and session state as content changes.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import math
import unicodedata
N = 1
observations = []
def solve(action, p):
    if action == 'dedupe-context':
        return list(dict.fromkeys((x['command'],x['context']) for x in p))
    if action == 'promote':
        return [p['id']]+[x for x in p['history'] if x!=p['id']]
    if action == 'recent-rank':
        return [x['id'] for x in sorted(p,key=lambda x:(-x['last_used'],-x['uses']))]
    if action == 'retired':
        return [x for x in p['history'] if x in p['commands']]
    if action == 'limit':
        return p['history'][-p['limit']:]
    if action == 'private-context':
        return [x for x in p if not x['private']]
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('dedupe-context contract', solve('dedupe-context', [{'command':'open','context':N},{'command':'open','context':N+1}]), [('open',N),('open',N+1)])
check('promote contract', solve('promote', {'id':N,'history':[N+1,N]}), [N,N+1])
check('recent-rank contract', solve('recent-rank', [{'id':'old','last_used':N,'uses':20},{'id':'new','last_used':N+5,'uses':1}]), ['new','old'])
check('retired contract', solve('retired', {'history':[N,N+1],'commands':[N+1,N+2]}), [N+1])
check('limit contract', solve('limit', {'history':list(range(N+4)),'limit':2}), [0,1])
check('private-context contract', solve('private-context', [{'id':N,'private':True,'context':'secret'},{'id':N+1,'private':False,'context':'public'}]), [{'id':N+1,'private':False,'context':'public'}])
check('unknown operation', solve('unknown', {}), {'error': 'unsupported menu operation'})
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
dedupe-context contract	`[['open', 1], ['open', 2]]`	`[['open', 1], ['open', 2]]`	Passed
promote contract	`[1, 2]`	`[1, 2]`	Passed
recent-rank contract	`['new', 'old']`	`['new', 'old']`	Passed
retired contract	`[2]`	`[2]`	Passed
limit contract	`[3, 4]`	`[0, 1]`	Failed
private-context contract	`[{'context': 'public', 'id': 2, 'private': False}]`	`[{'context': 'public', 'id': 2, 'private': False}]`	Passed
unknown operation	`{'error': 'unsupported menu operation'}`	`{'error': 'unsupported menu operation'}`	Passed

SHA-256 / 5e9efc7c45f0b26fe611f9adf789fd95cca5adbcd0b198be897bdebf5600e6b4

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import math
import unicodedata
N = 1
observations = []
def solve(action, p):
    if action == 'dedupe-context':
        return list(dict.fromkeys((x['command'],x['context']) for x in p))
    if action == 'promote':
        return [p['id']]+[x for x in p['history'] if x!=p['id']]
    if action == 'recent-rank':
        return [x['id'] for x in sorted(p,key=lambda x:(-x['last_used'],-x['uses']))]
    if action == 'retired':
        return [x for x in p['history'] if x in p['commands']]
    if action == 'limit':
        return p['history'][:p['limit']+1]
    if action == 'private-context':
        return [x for x in p if not x['private']]
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('dedupe-context contract', solve('dedupe-context', [{'command':'open','context':N},{'command':'open','context':N+1}]), [('open',N),('open',N+1)])
check('promote contract', solve('promote', {'id':N,'history':[N+1,N]}), [N,N+1])
check('recent-rank contract', solve('recent-rank', [{'id':'old','last_used':N,'uses':20},{'id':'new','last_used':N+5,'uses':1}]), ['new','old'])
check('retired contract', solve('retired', {'history':[N,N+1],'commands':[N+1,N+2]}), [N+1])
check('limit contract', solve('limit', {'history':list(range(N+4)),'limit':2}), [0,1])
check('private-context contract', solve('private-context', [{'id':N,'private':True,'context':'secret'},{'id':N+1,'private':False,'context':'public'}]), [{'id':N+1,'private':False,'context':'public'}])
check('unknown operation', solve('unknown', {}), {'error': 'unsupported menu operation'})
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
dedupe-context contract	`[['open', 1], ['open', 2]]`	`[['open', 1], ['open', 2]]`	Passed
promote contract	`[1, 2]`	`[1, 2]`	Passed
recent-rank contract	`['new', 'old']`	`['new', 'old']`	Passed
retired contract	`[2]`	`[2]`	Passed
limit contract	`[0, 1, 2]`	`[0, 1]`	Failed
private-context contract	`[{'context': 'public', 'id': 2, 'private': False}]`	`[{'context': 'public', 'id': 2, 'private': False}]`	Passed
unknown operation	`{'error': 'unsupported menu operation'}`	`{'error': 'unsupported menu operation'}`	Passed

SHA-256 / 70a44403584d047edde62f7a645cb3f6bc4230b6ef6b82b329f6e8b8f4096933

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.

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

Verification & scope

Offline supplied-valid-payload model; excludes DOM, keyboard, focus, selection, announcements and browser conformance. 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 2026-09-29T14:42:18.504239+00:00.

Case digest / b749ca1523c3519b0e4dc5b6e045e5733a337ec59c806f3723d453e77f0e4db5