FA-23211 / Autocomplete interactions / Open access
Search normalization versus displayed autocomplete text: result query is compared with unnormalized visible draft · case 01
The match-key completion transition produces an incorrect observable state.
ROOT CAUSE
At query-display/match-key, the implementation evaluates `d['result_query']==d['draft']` instead of preserving the specified completion transition.
VERIFIED REPAIR
Implement the match-key contract using `d['result_query']==d['normalized']`.
Unsuccessful approach: The attempted repair uses `False`, which still violates a normal or boundary completion fixture.
Case contract
This controlled ASCII picker normalizes lookup by stripping outer whitespace and lowercasing, while preserving exact user draft and canonical option labels for display and commit. Matching offsets apply to the normalized query only; a normalization-equivalent edit still advances the display epoch.
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 == 'lookup': return d['draft'].strip().lower()
if event == 'display': return d['draft']
if event == 'commit-label': return d['label']
if event == 'commit-id': return d['id']
if event == 'match-key': return d['result_query']==d['draft']
if event == 'offset': return [d['prefix_space'],d['prefix_space']+len(d['normalized'])]
if event == 'display-epoch': return d['epoch']+1
if event == 'query-equivalent': return d['old']==d['normalized']
if event == 'caret-display': return d['caret']
if event == 'empty-query': return 'empty' if not d['normalized'] else 'typed'
return {'unchanged': True}
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'draft':' PeA ','label':'Pear','id':'p1','normalized':'pea','prefix_space':2,'epoch':N,'old':'pea','result_query':'pea','caret':5}
boundary = {'draft':'','label':'','id':'','normalized':'','prefix_space':0,'epoch':N,'old':'','result_query':'','caret':0}
check('normal lookup', solve('lookup', normal), 'pea')
check('boundary lookup', solve('lookup', boundary), '')
check('normal display', solve('display', normal), ' PeA ')
check('boundary display', solve('display', boundary), '')
check('normal commit-label', solve('commit-label', normal), 'Pear')
check('boundary commit-label', solve('commit-label', boundary), '')
check('normal commit-id', solve('commit-id', normal), 'p1')
check('boundary commit-id', solve('commit-id', boundary), '')
check('normal match-key', solve('match-key', normal), True)
check('boundary match-key', solve('match-key', boundary), True)
check('normal offset', solve('offset', normal), [2,5])
check('boundary offset', solve('offset', boundary), [0,0])
check('normal display-epoch', solve('display-epoch', normal), N+1)
check('boundary display-epoch', solve('display-epoch', boundary), N+1)
check('normal query-equivalent', solve('query-equivalent', normal), True)
check('boundary query-equivalent', solve('query-equivalent', boundary), True)
check('normal caret-display', solve('caret-display', normal), 5)
check('boundary caret-display', solve('caret-display', boundary), 0)
check('normal empty-query', solve('empty-query', normal), 'typed')
check('boundary empty-query', solve('empty-query', boundary), 'empty')
variant = dict(normal, **{'draft':' '*N+'PEAR'+' '*N})
check('variant query or selection payload', solve('lookup', variant), 'pear')
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 lookup | pea | pea | Passed |
| boundary lookup | | | Passed |
| normal display | PeA | PeA | Passed |
| boundary display | | | Passed |
| normal commit-label | Pear | Pear | Passed |
| boundary commit-label | | | Passed |
| normal commit-id | p1 | p1 | Passed |
| boundary commit-id | | | Passed |
| normal match-key | False | True | Failed |
| boundary match-key | True | True | Passed |
| normal offset | [2, 5] | [2, 5] | Passed |
| boundary offset | [0, 0] | [0, 0] | Passed |
| normal display-epoch | 2 | 2 | Passed |
| boundary display-epoch | 2 | 2 | Passed |
| normal query-equivalent | True | True | Passed |
| boundary query-equivalent | True | True | Passed |
| normal caret-display | 5 | 5 | Passed |
| boundary caret-display | 0 | 0 | Passed |
| normal empty-query | typed | typed | Passed |
| boundary empty-query | empty | empty | Passed |
| variant query or selection payload | pear | pear | Passed |
| unknown completion event | {'unchanged': True} | {'unchanged': True} | Passed |
SHA-256 / bde2f4b1d10a140e58b24a9606a022a8a3ae4c865726b3e45a29552c78d61ae2
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 == 'lookup': return d['draft'].strip().lower()
if event == 'display': return d['draft']
if event == 'commit-label': return d['label']
if event == 'commit-id': return d['id']
if event == 'match-key': return False
if event == 'offset': return [d['prefix_space'],d['prefix_space']+len(d['normalized'])]
if event == 'display-epoch': return d['epoch']+1
if event == 'query-equivalent': return d['old']==d['normalized']
if event == 'caret-display': return d['caret']
if event == 'empty-query': return 'empty' if not d['normalized'] else 'typed'
return {'unchanged': True}
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'draft':' PeA ','label':'Pear','id':'p1','normalized':'pea','prefix_space':2,'epoch':N,'old':'pea','result_query':'pea','caret':5}
boundary = {'draft':'','label':'','id':'','normalized':'','prefix_space':0,'epoch':N,'old':'','result_query':'','caret':0}
check('normal lookup', solve('lookup', normal), 'pea')
check('boundary lookup', solve('lookup', boundary), '')
check('normal display', solve('display', normal), ' PeA ')
check('boundary display', solve('display', boundary), '')
check('normal commit-label', solve('commit-label', normal), 'Pear')
check('boundary commit-label', solve('commit-label', boundary), '')
check('normal commit-id', solve('commit-id', normal), 'p1')
check('boundary commit-id', solve('commit-id', boundary), '')
check('normal match-key', solve('match-key', normal), True)
check('boundary match-key', solve('match-key', boundary), True)
check('normal offset', solve('offset', normal), [2,5])
check('boundary offset', solve('offset', boundary), [0,0])
check('normal display-epoch', solve('display-epoch', normal), N+1)
check('boundary display-epoch', solve('display-epoch', boundary), N+1)
check('normal query-equivalent', solve('query-equivalent', normal), True)
check('boundary query-equivalent', solve('query-equivalent', boundary), True)
check('normal caret-display', solve('caret-display', normal), 5)
check('boundary caret-display', solve('caret-display', boundary), 0)
check('normal empty-query', solve('empty-query', normal), 'typed')
check('boundary empty-query', solve('empty-query', boundary), 'empty')
variant = dict(normal, **{'draft':' '*N+'PEAR'+' '*N})
check('variant query or selection payload', solve('lookup', variant), 'pear')
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 lookup | pea | pea | Passed |
| boundary lookup | | | Passed |
| normal display | PeA | PeA | Passed |
| boundary display | | | Passed |
| normal commit-label | Pear | Pear | Passed |
| boundary commit-label | | | Passed |
| normal commit-id | p1 | p1 | Passed |
| boundary commit-id | | | Passed |
| normal match-key | False | True | Failed |
| boundary match-key | False | True | Failed |
| normal offset | [2, 5] | [2, 5] | Passed |
| boundary offset | [0, 0] | [0, 0] | Passed |
| normal display-epoch | 2 | 2 | Passed |
| boundary display-epoch | 2 | 2 | Passed |
| normal query-equivalent | True | True | Passed |
| boundary query-equivalent | True | True | Passed |
| normal caret-display | 5 | 5 | Passed |
| boundary caret-display | 0 | 0 | Passed |
| normal empty-query | typed | typed | Passed |
| boundary empty-query | empty | empty | Passed |
| variant query or selection payload | pear | pear | Passed |
| unknown completion event | {'unchanged': True} | {'unchanged': True} | Passed |
SHA-256 / 2209a7dfa272bea531ff34aa3449618e2cdee4b637f01052f6b7327d80922bac
3 / The verified repair
Exit 0"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(event, d):
if event == 'lookup': return d['draft'].strip().lower()
if event == 'display': return d['draft']
if event == 'commit-label': return d['label']
if event == 'commit-id': return d['id']
if event == 'match-key': return d['result_query']==d['normalized']
if event == 'offset': return [d['prefix_space'],d['prefix_space']+len(d['normalized'])]
if event == 'display-epoch': return d['epoch']+1
if event == 'query-equivalent': return d['old']==d['normalized']
if event == 'caret-display': return d['caret']
if event == 'empty-query': return 'empty' if not d['normalized'] else 'typed'
return {'unchanged': True}
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'draft':' PeA ','label':'Pear','id':'p1','normalized':'pea','prefix_space':2,'epoch':N,'old':'pea','result_query':'pea','caret':5}
boundary = {'draft':'','label':'','id':'','normalized':'','prefix_space':0,'epoch':N,'old':'','result_query':'','caret':0}
check('normal lookup', solve('lookup', normal), 'pea')
check('boundary lookup', solve('lookup', boundary), '')
check('normal display', solve('display', normal), ' PeA ')
check('boundary display', solve('display', boundary), '')
check('normal commit-label', solve('commit-label', normal), 'Pear')
check('boundary commit-label', solve('commit-label', boundary), '')
check('normal commit-id', solve('commit-id', normal), 'p1')
check('boundary commit-id', solve('commit-id', boundary), '')
check('normal match-key', solve('match-key', normal), True)
check('boundary match-key', solve('match-key', boundary), True)
check('normal offset', solve('offset', normal), [2,5])
check('boundary offset', solve('offset', boundary), [0,0])
check('normal display-epoch', solve('display-epoch', normal), N+1)
check('boundary display-epoch', solve('display-epoch', boundary), N+1)
check('normal query-equivalent', solve('query-equivalent', normal), True)
check('boundary query-equivalent', solve('query-equivalent', boundary), True)
check('normal caret-display', solve('caret-display', normal), 5)
check('boundary caret-display', solve('caret-display', boundary), 0)
check('normal empty-query', solve('empty-query', normal), 'typed')
check('boundary empty-query', solve('empty-query', boundary), 'empty')
variant = dict(normal, **{'draft':' '*N+'PEAR'+' '*N})
check('variant query or selection payload', solve('lookup', variant), 'pear')
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 lookup | pea | pea | Passed |
| boundary lookup | | | Passed |
| normal display | PeA | PeA | Passed |
| boundary display | | | Passed |
| normal commit-label | Pear | Pear | Passed |
| boundary commit-label | | | Passed |
| normal commit-id | p1 | p1 | Passed |
| boundary commit-id | | | Passed |
| normal match-key | True | True | Passed |
| boundary match-key | True | True | Passed |
| normal offset | [2, 5] | [2, 5] | Passed |
| boundary offset | [0, 0] | [0, 0] | Passed |
| normal display-epoch | 2 | 2 | Passed |
| boundary display-epoch | 2 | 2 | Passed |
| normal query-equivalent | True | True | Passed |
| boundary query-equivalent | True | True | Passed |
| normal caret-display | 5 | 5 | Passed |
| boundary caret-display | 0 | 0 | Passed |
| normal empty-query | typed | typed | Passed |
| boundary empty-query | empty | empty | Passed |
| variant query or selection payload | pear | pear | Passed |
| unknown completion event | {'unchanged': True} | {'unchanged': True} | Passed |
SHA-256 / e1011903c77a7f2dd23116983bb8581562c25d3d682a4fd7e477381fa5590de1
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 2026-09-29T14:40:45.535259+00:00.
Case digest / c2c0e457b917e3b60ae2ff98fe1388ce60054b681b740644bd4d5a803d87c910