FA-32471 / Menu interactions / Open access

Short lazy menu page is mistaken for exhaustion · case 01

Short lazy menu page is mistaken for exhaustion.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The lazy-pages model applies `not p['items']` at its done operation instead of the stipulated transformation.

THE FAILURE

The lazy-pages model applies `not p['items']` at its done operation instead of the stipulated transformation.

Unsuccessful approach: The attempted repair `len(p['items'])<p['limit']` still violates the done oracle.

Case contract

Lazy submenu pages retain provider order, unique IDs and opaque cursors; loading indicators disappear on final empty results.

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 == 'append':
        return p['old']+[x for x in p['page'] if x not in p['old']]
    if action == 'cursor':
        return p['next']
    if action == 'done':
        return not p['items']
    if action == 'empty':
        return [] if p['done'] and not p['items'] else p['items']
    if action == 'retry':
        return p['failed']
    if action == 'footer':
        return p['rows'][:-1]+p['page']+[p['rows'][-1]]
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('append contract', solve('append', {'old':[N],'page':[N,N+1]}), [N,N+1])
check('cursor contract', solve('cursor', {'next':'cursor'+str(N),'previous':'old','items':[1,2]}), 'cursor'+str(N))
check('done contract', solve('done', {'next':'next'+str(N),'items':[],'limit':20}), False)
check('empty contract', solve('empty', {'done':True,'items':[],'request':N}), [])
check('retry contract', solve('retry', {'failed':'failed'+str(N),'next':'next'}), 'failed'+str(N))
check('footer contract', solve('footer', {'rows':['existing','footer'],'page':['new'+str(N)]}), ['existing','new'+str(N),'footer'])
check('unknown operation', solve('unknown', {}), {'error': 'unsupported menu operation'})
check('retain earlier page', solve('append', {'old':[N-1,N], 'page':[N,N+1]}), [N-1,N,N+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
append contract	`[1, 2]`	`[1, 2]`	Passed
cursor contract	`cursor1`	`cursor1`	Passed
done contract	`True`	`False`	Failed
empty contract	`[]`	`[]`	Passed
retry contract	`failed1`	`failed1`	Passed
footer contract	`['existing', 'new1', 'footer']`	`['existing', 'new1', 'footer']`	Passed
unknown operation	`{'error': 'unsupported menu operation'}`	`{'error': 'unsupported menu operation'}`	Passed
retain earlier page	`[0, 1, 2]`	`[0, 1, 2]`	Passed

SHA-256 / 1f5b55af6ab09c3547cea54ff88e2e8fbf848285d3a982dcd7c9e95c6ffdb0bf

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 == 'append':
        return p['old']+[x for x in p['page'] if x not in p['old']]
    if action == 'cursor':
        return p['next']
    if action == 'done':
        return len(p['items'])<p['limit']
    if action == 'empty':
        return [] if p['done'] and not p['items'] else p['items']
    if action == 'retry':
        return p['failed']
    if action == 'footer':
        return p['rows'][:-1]+p['page']+[p['rows'][-1]]
    return {'error': 'unsupported menu operation'}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('append contract', solve('append', {'old':[N],'page':[N,N+1]}), [N,N+1])
check('cursor contract', solve('cursor', {'next':'cursor'+str(N),'previous':'old','items':[1,2]}), 'cursor'+str(N))
check('done contract', solve('done', {'next':'next'+str(N),'items':[],'limit':20}), False)
check('empty contract', solve('empty', {'done':True,'items':[],'request':N}), [])
check('retry contract', solve('retry', {'failed':'failed'+str(N),'next':'next'}), 'failed'+str(N))
check('footer contract', solve('footer', {'rows':['existing','footer'],'page':['new'+str(N)]}), ['existing','new'+str(N),'footer'])
check('unknown operation', solve('unknown', {}), {'error': 'unsupported menu operation'})
check('retain earlier page', solve('append', {'old':[N-1,N], 'page':[N,N+1]}), [N-1,N,N+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
append contract	`[1, 2]`	`[1, 2]`	Passed
cursor contract	`cursor1`	`cursor1`	Passed
done contract	`True`	`False`	Failed
empty contract	`[]`	`[]`	Passed
retry contract	`failed1`	`failed1`	Passed
footer contract	`['existing', 'new1', 'footer']`	`['existing', 'new1', 'footer']`	Passed
unknown operation	`{'error': 'unsupported menu operation'}`	`{'error': 'unsupported menu operation'}`	Passed
retain earlier page	`[0, 1, 2]`	`[0, 1, 2]`	Passed

SHA-256 / 75dfb3c64d4fec75fac3c731c8aca34094723d24259b4cd784da24ef00ea7996

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 8 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 2026-09-29T14:42:12.677943+00:00.

Case digest / 1495e84841dc9e61e7f44df569aeb76c56b747dd8c4d499481b3badf5d9a4505