FA-22891 / Autocomplete interactions / Open access

External text autofill in autocomplete: external autofill leaves the prior search fragment as the draft · case 01

The draft completion transition produces an incorrect observable state.

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

ROOT CAUSE

At autofill-reconcile/draft, the implementation evaluates `d['old_query']` instead of preserving the specified completion transition.

THE FAILURE

At autofill-reconcile/draft, the implementation evaluates `d['old_query']` instead of preserving the specified completion transition.

Unsuccessful approach: The attempted repair uses `d['old_value']`, which still violates a normal or boundary completion fixture.

Case contract

Externally replaced input text is reconciled as draft text. It commits an identifier only for one exact eligible label match, never from old highlight or fuzzy matching. Ambiguous labels retain unresolved draft, and the replacement invalidates previous suggestion requests and ghost text.

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 == 'draft': return d['old_query']
    if event == 'matches': return [x for x in d['matches'] if x in d['eligible']]
    if event == 'ambiguous': return d['matches'][0] if len(d['matches'])==1 else None
    if event == 'exact': return d['matches'][0] if d['exact'] and len(d['matches'])==1 else None
    if event == 'unresolved': return None
    if event == 'ghost': return ''
    if event == 'exact-display': return d['text'] if d['exact'] else None
    if event == 'query-trigger': return {'query':d['text'],'epoch':d['epoch']+1}
    if event == 'touched': return d['touched']
    if event == 'hover-witness': return d['highlight'] in d['matches'] and d['exact']
    return {'unchanged': True}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'text':'Pear','old_query':'pe','matches':['p1','p2'],'eligible':['p2'],'old_value':'p0','highlight':'p3','ghost':'ach','epoch':N,'exact':False,'touched':False}
boundary = {'text':'','old_query':'','matches':[''],'eligible':[''],'old_value':None,'highlight':None,'ghost':'','epoch':N,'exact':True,'touched':True}
check('normal draft', solve('draft', normal), 'Pear')
check('boundary draft', solve('draft', boundary), '')
check('normal matches', solve('matches', normal), ['p2'])
check('boundary matches', solve('matches', boundary), [''])
check('normal ambiguous', solve('ambiguous', normal), None)
check('boundary ambiguous', solve('ambiguous', boundary), '')
check('normal exact', solve('exact', normal), None)
check('boundary exact', solve('exact', boundary), '')
check('normal unresolved', solve('unresolved', normal), None)
check('boundary unresolved', solve('unresolved', boundary), None)
check('normal ghost', solve('ghost', normal), '')
check('boundary ghost', solve('ghost', boundary), '')
check('normal exact-display', solve('exact-display', normal), None)
check('boundary exact-display', solve('exact-display', boundary), '')
check('normal query-trigger', solve('query-trigger', normal), {'query':'Pear','epoch':N+1})
check('boundary query-trigger', solve('query-trigger', boundary), {'query':'','epoch':N+1})
check('normal touched', solve('touched', normal), False)
check('boundary touched', solve('touched', boundary), True)
check('normal hover-witness', solve('hover-witness', normal), False)
check('boundary hover-witness', solve('hover-witness', boundary), False)
variant = dict(normal, **{'text':'q'*N})
check('variant query or selection payload', solve('draft', variant), 'q'*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 draft	`pe`	`Pear`	Failed
boundary draft			Passed
normal matches	`['p2']`	`['p2']`	Passed
boundary matches	`['']`	`['']`	Passed
normal ambiguous	`None`	`None`	Passed
boundary ambiguous			Passed
normal exact	`None`	`None`	Passed
boundary exact			Passed
normal unresolved	`None`	`None`	Passed
boundary unresolved	`None`	`None`	Passed
normal ghost			Passed
boundary ghost			Passed
normal exact-display	`None`	`None`	Passed
boundary exact-display			Passed
normal query-trigger	`{'epoch': 2, 'query': 'Pear'}`	`{'epoch': 2, 'query': 'Pear'}`	Passed
boundary query-trigger	`{'epoch': 2, 'query': ''}`	`{'epoch': 2, 'query': ''}`	Passed
normal touched	`False`	`False`	Passed
boundary touched	`True`	`True`	Passed
normal hover-witness	`False`	`False`	Passed
boundary hover-witness	`False`	`False`	Passed
variant query or selection payload	`pe`	`q`	Failed
unknown completion event	`{'unchanged': True}`	`{'unchanged': True}`	Passed

SHA-256 / 97f5dedd65c480a7569b98345115222e76ffca5374416569870dc4407c6e62ad

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 == 'draft': return d['old_value']
    if event == 'matches': return [x for x in d['matches'] if x in d['eligible']]
    if event == 'ambiguous': return d['matches'][0] if len(d['matches'])==1 else None
    if event == 'exact': return d['matches'][0] if d['exact'] and len(d['matches'])==1 else None
    if event == 'unresolved': return None
    if event == 'ghost': return ''
    if event == 'exact-display': return d['text'] if d['exact'] else None
    if event == 'query-trigger': return {'query':d['text'],'epoch':d['epoch']+1}
    if event == 'touched': return d['touched']
    if event == 'hover-witness': return d['highlight'] in d['matches'] and d['exact']
    return {'unchanged': True}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'text':'Pear','old_query':'pe','matches':['p1','p2'],'eligible':['p2'],'old_value':'p0','highlight':'p3','ghost':'ach','epoch':N,'exact':False,'touched':False}
boundary = {'text':'','old_query':'','matches':[''],'eligible':[''],'old_value':None,'highlight':None,'ghost':'','epoch':N,'exact':True,'touched':True}
check('normal draft', solve('draft', normal), 'Pear')
check('boundary draft', solve('draft', boundary), '')
check('normal matches', solve('matches', normal), ['p2'])
check('boundary matches', solve('matches', boundary), [''])
check('normal ambiguous', solve('ambiguous', normal), None)
check('boundary ambiguous', solve('ambiguous', boundary), '')
check('normal exact', solve('exact', normal), None)
check('boundary exact', solve('exact', boundary), '')
check('normal unresolved', solve('unresolved', normal), None)
check('boundary unresolved', solve('unresolved', boundary), None)
check('normal ghost', solve('ghost', normal), '')
check('boundary ghost', solve('ghost', boundary), '')
check('normal exact-display', solve('exact-display', normal), None)
check('boundary exact-display', solve('exact-display', boundary), '')
check('normal query-trigger', solve('query-trigger', normal), {'query':'Pear','epoch':N+1})
check('boundary query-trigger', solve('query-trigger', boundary), {'query':'','epoch':N+1})
check('normal touched', solve('touched', normal), False)
check('boundary touched', solve('touched', boundary), True)
check('normal hover-witness', solve('hover-witness', normal), False)
check('boundary hover-witness', solve('hover-witness', boundary), False)
variant = dict(normal, **{'text':'q'*N})
check('variant query or selection payload', solve('draft', variant), 'q'*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 draft	`p0`	`Pear`	Failed
boundary draft	`None`		Failed
normal matches	`['p2']`	`['p2']`	Passed
boundary matches	`['']`	`['']`	Passed
normal ambiguous	`None`	`None`	Passed
boundary ambiguous			Passed
normal exact	`None`	`None`	Passed
boundary exact			Passed
normal unresolved	`None`	`None`	Passed
boundary unresolved	`None`	`None`	Passed
normal ghost			Passed
boundary ghost			Passed
normal exact-display	`None`	`None`	Passed
boundary exact-display			Passed
normal query-trigger	`{'epoch': 2, 'query': 'Pear'}`	`{'epoch': 2, 'query': 'Pear'}`	Passed
boundary query-trigger	`{'epoch': 2, 'query': ''}`	`{'epoch': 2, 'query': ''}`	Passed
normal touched	`False`	`False`	Passed
boundary touched	`True`	`True`	Passed
normal hover-witness	`False`	`False`	Passed
boundary hover-witness	`False`	`False`	Passed
variant query or selection payload	`p0`	`q`	Failed
unknown completion event	`{'unchanged': True}`	`{'unchanged': True}`	Passed

SHA-256 / 81ecb0e0d7d142ffe6ef7eee481a6d45129d68da4e376a378bc39898a32e9921

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 2026-09-29T14:40:42.961252+00:00.

Case digest / 9fb5e269023018e59684fff86f7006c2f8466b9236333b3fc1ef099999d3eba3