FA-22376 / Autocomplete interactions / Open access

Federated suggestion sections: empty local section causes the entire picker to show no results · case 01

The source-empty completion transition produces an incorrect observable state.

Verified by executionVariant 1 · 22 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

At source-sections/source-empty, the implementation evaluates `not d['local']` instead of preserving the specified completion transition.

THE FAILURE

At source-sections/source-empty, the implementation evaluates `not d['local']` instead of preserving the specified completion transition.

Unsuccessful approach: The attempted repair uses `not d['remote'] or not d['local']`, which still violates a normal or boundary completion fixture.

Case contract

Local-history and remote suggestions are separate ordered sections. Stable identity includes source namespace. Empty sections have no header; pending remote work does not hide completed local results. Section headers are display rows, never commit candidates.

Why this case matters

Autocomplete couples draft text, suggestion identity and asynchronous presentation; this bounded lifecycle model isolates one observable interaction defect.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(event, d):
    if event == 'order': return d['local']+d['remote']
    if event == 'identity': return [d['row_source'],d['row_id']]
    if event == 'local-header': return d['local_title'] if d['local'] else None
    if event == 'remote-header': return d['remote_title'] if d['remote'] else None
    if event == 'local-ready': return d['local']
    if event == 'header-commit': return d['row_id'] if d['row_kind']=='option' else None
    if event == 'count': return len(d['local'])+len(d['remote'])
    if event == 'source-empty': return not d['local']
    if event == 'remote-marker': return d['remote_pending']
    if event == 'remote-offset': return len(d['local'])+(1 if d['local'] else 0)
    return {'unchanged': True}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'local':['x','y'],'remote':['x','z'],'local_title':'Recent','remote_title':'Directory','remote_pending':True,'row_kind':'header','row_source':'remote','row_id':'x','epoch':N}
boundary = {'local':[],'remote':['w'],'local_title':'Recent','remote_title':'Directory','remote_pending':False,'row_kind':'option','row_source':'local','row_id':'','epoch':N}
check('normal order', solve('order', normal), ['x','y','x','z'])
check('boundary order', solve('order', boundary), ['w'])
check('normal identity', solve('identity', normal), ['remote','x'])
check('boundary identity', solve('identity', boundary), ['local',''])
check('normal local-header', solve('local-header', normal), 'Recent')
check('boundary local-header', solve('local-header', boundary), None)
check('normal remote-header', solve('remote-header', normal), 'Directory')
check('boundary remote-header', solve('remote-header', boundary), 'Directory')
check('normal local-ready', solve('local-ready', normal), ['x','y'])
check('boundary local-ready', solve('local-ready', boundary), [])
check('normal header-commit', solve('header-commit', normal), None)
check('boundary header-commit', solve('header-commit', boundary), '')
check('normal count', solve('count', normal), 4)
check('boundary count', solve('count', boundary), 1)
check('normal source-empty', solve('source-empty', normal), False)
check('boundary source-empty', solve('source-empty', boundary), False)
check('normal remote-marker', solve('remote-marker', normal), True)
check('boundary remote-marker', solve('remote-marker', boundary), False)
check('normal remote-offset', solve('remote-offset', normal), 3)
check('boundary remote-offset', solve('remote-offset', boundary), 0)
variant = dict(normal, **{'row_id':'id'+str(N)})
check('variant query or selection payload', solve('identity', variant), ['remote','id'+str(N)])
check('unknown completion event', solve('unrecognized', normal), {'unchanged': True})
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
normal order	`['x', 'y', 'x', 'z']`	`['x', 'y', 'x', 'z']`	Passed
boundary order	`['w']`	`['w']`	Passed
normal identity	`['remote', 'x']`	`['remote', 'x']`	Passed
boundary identity	`['local', '']`	`['local', '']`	Passed
normal local-header	`Recent`	`Recent`	Passed
boundary local-header	`None`	`None`	Passed
normal remote-header	`Directory`	`Directory`	Passed
boundary remote-header	`Directory`	`Directory`	Passed
normal local-ready	`['x', 'y']`	`['x', 'y']`	Passed
boundary local-ready	`[]`	`[]`	Passed
normal header-commit	`None`	`None`	Passed
boundary header-commit			Passed
normal count	`4`	`4`	Passed
boundary count	`1`	`1`	Passed
normal source-empty	`False`	`False`	Passed
boundary source-empty	`True`	`False`	Failed
normal remote-marker	`True`	`True`	Passed
boundary remote-marker	`False`	`False`	Passed
normal remote-offset	`3`	`3`	Passed
boundary remote-offset	`0`	`0`	Passed
variant query or selection payload	`['remote', 'id1']`	`['remote', 'id1']`	Passed
unknown completion event	`{'unchanged': True}`	`{'unchanged': True}`	Passed

SHA-256 / a222bbabf0fa066f6ce4785a9c332f0ecd765811d1e4eb7307b78cb239227f38

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(event, d):
    if event == 'order': return d['local']+d['remote']
    if event == 'identity': return [d['row_source'],d['row_id']]
    if event == 'local-header': return d['local_title'] if d['local'] else None
    if event == 'remote-header': return d['remote_title'] if d['remote'] else None
    if event == 'local-ready': return d['local']
    if event == 'header-commit': return d['row_id'] if d['row_kind']=='option' else None
    if event == 'count': return len(d['local'])+len(d['remote'])
    if event == 'source-empty': return not d['remote'] or not d['local']
    if event == 'remote-marker': return d['remote_pending']
    if event == 'remote-offset': return len(d['local'])+(1 if d['local'] else 0)
    return {'unchanged': True}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'local':['x','y'],'remote':['x','z'],'local_title':'Recent','remote_title':'Directory','remote_pending':True,'row_kind':'header','row_source':'remote','row_id':'x','epoch':N}
boundary = {'local':[],'remote':['w'],'local_title':'Recent','remote_title':'Directory','remote_pending':False,'row_kind':'option','row_source':'local','row_id':'','epoch':N}
check('normal order', solve('order', normal), ['x','y','x','z'])
check('boundary order', solve('order', boundary), ['w'])
check('normal identity', solve('identity', normal), ['remote','x'])
check('boundary identity', solve('identity', boundary), ['local',''])
check('normal local-header', solve('local-header', normal), 'Recent')
check('boundary local-header', solve('local-header', boundary), None)
check('normal remote-header', solve('remote-header', normal), 'Directory')
check('boundary remote-header', solve('remote-header', boundary), 'Directory')
check('normal local-ready', solve('local-ready', normal), ['x','y'])
check('boundary local-ready', solve('local-ready', boundary), [])
check('normal header-commit', solve('header-commit', normal), None)
check('boundary header-commit', solve('header-commit', boundary), '')
check('normal count', solve('count', normal), 4)
check('boundary count', solve('count', boundary), 1)
check('normal source-empty', solve('source-empty', normal), False)
check('boundary source-empty', solve('source-empty', boundary), False)
check('normal remote-marker', solve('remote-marker', normal), True)
check('boundary remote-marker', solve('remote-marker', boundary), False)
check('normal remote-offset', solve('remote-offset', normal), 3)
check('boundary remote-offset', solve('remote-offset', boundary), 0)
variant = dict(normal, **{'row_id':'id'+str(N)})
check('variant query or selection payload', solve('identity', variant), ['remote','id'+str(N)])
check('unknown completion event', solve('unrecognized', normal), {'unchanged': True})
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
normal order	`['x', 'y', 'x', 'z']`	`['x', 'y', 'x', 'z']`	Passed
boundary order	`['w']`	`['w']`	Passed
normal identity	`['remote', 'x']`	`['remote', 'x']`	Passed
boundary identity	`['local', '']`	`['local', '']`	Passed
normal local-header	`Recent`	`Recent`	Passed
boundary local-header	`None`	`None`	Passed
normal remote-header	`Directory`	`Directory`	Passed
boundary remote-header	`Directory`	`Directory`	Passed
normal local-ready	`['x', 'y']`	`['x', 'y']`	Passed
boundary local-ready	`[]`	`[]`	Passed
normal header-commit	`None`	`None`	Passed
boundary header-commit			Passed
normal count	`4`	`4`	Passed
boundary count	`1`	`1`	Passed
normal source-empty	`False`	`False`	Passed
boundary source-empty	`True`	`False`	Failed
normal remote-marker	`True`	`True`	Passed
boundary remote-marker	`False`	`False`	Passed
normal remote-offset	`3`	`3`	Passed
boundary remote-offset	`0`	`0`	Passed
variant query or selection payload	`['remote', 'id1']`	`['remote', 'id1']`	Passed
unknown completion event	`{'unchanged': True}`	`{'unchanged': True}`	Passed

SHA-256 / 448d6ee83e7f6035187b35e297b445c4e8836e0721b7623120e368f2e8d79fd0

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 22 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

Stipulated deterministic widget transition model; inputs are validated snapshots. It does not model browser event dispatch, network transport, or linguistic standards. 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 2026-09-29T14:40:37.945603+00:00.

Case digest / db01be13b2c9a31608a27cfac251a04ad96c045cfeaa458e14889ad439a08e98