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FA-33721 / Menu interactions / Open access

Nested menu provider receives the full root row budget · case 01

Nested menu provider receives the full root row budget.

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

ROOT CAUSE

The nested-provider-budgets model applies `p['budget']` at its remaining-rows operation instead of the stipulated transformation.

THE FAILURE

The nested-provider-budgets model applies `p['budget']` at its remaining-rows operation instead of the stipulated transformation.

Unsuccessful approach: The attempted repair `max(0,p['budget']-p['local_rows'])` still violates the remaining-rows oracle.

Case contract

Nested menu providers consume shared row and depth budgets and charge visible descendants exactly once; cached rows still occupy presentation budget.

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 == 'remaining-rows':
        return p['budget']
    if action == 'remaining-depth':
        return max(0,p['maximum']-p['depth'])
    if action == 'charge-cache':
        return len(p['fresh'])+len(p['cached'])
    if action == 'truncate-signal':
        return {'rows':p['rows'][:p['limit']],'truncated':len(p['rows'])>p['limit']}
    if action == 'reservation':
        return max(0,p['available']-sum(p['reservations'].values()))
    if action == 'release-reservation':
        return {k:v for k,v in p['reservations'].items() if k!=p['provider']}
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('remaining-rows contract', solve('remaining-rows', {'budget':N+10,'ancestor_rows':4,'local_rows':1}), N+6)
check('remaining-depth contract', solve('remaining-depth', {'maximum':N+6,'depth':2}), N+4)
check('charge-cache contract', solve('charge-cache', {'fresh':[N],'cached':[N+1,N+2]}), 3)
check('truncate-signal contract', solve('truncate-signal', {'rows':list(range(N+3)),'limit':2}), {'rows':[0,1],'truncated':True})
check('reservation contract', solve('reservation', {'available':N+10,'reservations':{'a':2,'b':3}}), N+5)
check('release-reservation contract', solve('release-reservation', {'reservations':{'a':N,'b':N+1},'provider':'a','used':1}), {'b':N+1})
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 fixtureActualExpectedOutcome
remaining-rows contract117Failed
remaining-depth contract55Passed
charge-cache contract33Passed
truncate-signal contract{'rows': [0, 1], 'truncated': True}{'rows': [0, 1], 'truncated': True}Passed
reservation contract66Passed
release-reservation contract{'b': 2}{'b': 2}Passed
unknown operation{'error': 'unsupported menu operation'}{'error': 'unsupported menu operation'}Passed

SHA-256 / f547c4266eb26bdf5e4fd38e9c117cfdd267ca1ef92e5c6b0369bdf2cf3914f4

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 == 'remaining-rows':
        return max(0,p['budget']-p['local_rows'])
    if action == 'remaining-depth':
        return max(0,p['maximum']-p['depth'])
    if action == 'charge-cache':
        return len(p['fresh'])+len(p['cached'])
    if action == 'truncate-signal':
        return {'rows':p['rows'][:p['limit']],'truncated':len(p['rows'])>p['limit']}
    if action == 'reservation':
        return max(0,p['available']-sum(p['reservations'].values()))
    if action == 'release-reservation':
        return {k:v for k,v in p['reservations'].items() if k!=p['provider']}
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('remaining-rows contract', solve('remaining-rows', {'budget':N+10,'ancestor_rows':4,'local_rows':1}), N+6)
check('remaining-depth contract', solve('remaining-depth', {'maximum':N+6,'depth':2}), N+4)
check('charge-cache contract', solve('charge-cache', {'fresh':[N],'cached':[N+1,N+2]}), 3)
check('truncate-signal contract', solve('truncate-signal', {'rows':list(range(N+3)),'limit':2}), {'rows':[0,1],'truncated':True})
check('reservation contract', solve('reservation', {'available':N+10,'reservations':{'a':2,'b':3}}), N+5)
check('release-reservation contract', solve('release-reservation', {'reservations':{'a':N,'b':N+1},'provider':'a','used':1}), {'b':N+1})
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 fixtureActualExpectedOutcome
remaining-rows contract107Failed
remaining-depth contract55Passed
charge-cache contract33Passed
truncate-signal contract{'rows': [0, 1], 'truncated': True}{'rows': [0, 1], 'truncated': True}Passed
reservation contract66Passed
release-reservation contract{'b': 2}{'b': 2}Passed
unknown operation{'error': 'unsupported menu operation'}{'error': 'unsupported menu operation'}Passed

SHA-256 / 1c83ae083a0674de354334c9dab5cf53a170e2f7b46fafd3b3fd6457119e74e1

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.

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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 2026-09-29T14:42:25.286736+00:00.

Case digest / 013d846c2299922ef3f3661033f69d39acba40230b0a4df13803b05925bb7f91