FA-32466 / Menu interactions / Open access

Submenu continuation cursor is synthesized from row count · case 01

Submenu continuation cursor is synthesized from row count.

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

ROOT CAUSE

The lazy-pages model applies `str(len(p['items']))` at its cursor operation instead of the stipulated transformation.

VERIFIED REPAIR

Apply `p['next']` at cursor.

Unsuccessful approach: The attempted repair `p['previous']` still violates the cursor 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 str(len(p['items']))
    if action == 'done':
        return p['next'] is None
    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	`2`	`cursor1`	Failed
done contract	`False`	`False`	Passed
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 / 6c7c418e4f79e23483e66d9d6f2e893e1469f4367b5c2078a320ebdb3cd01689

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['previous']
    if action == 'done':
        return p['next'] is None
    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	`old`	`cursor1`	Failed
done contract	`False`	`False`	Passed
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 / 8443b00999589e20a807ee288a7c2393b94595ba6a7b8d297908b7f6d3ea96cf

3 / The verified repair

Exit 0

"""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 p['next'] is None
    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	`False`	`False`	Passed
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 / 5bfca9a8ddb800e3b119f9f1ba50be7331836d94de2996ce55181293459161f6

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 2026-09-29T14:42:12.489268+00:00.

Case digest / 00368b67dd5ec8c3180ed64e88aa52580511f8405fdd4eb9f069245885becc71