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FA-22771 / Autocomplete interactions / Open access

Autocomplete form binding: multi-value autocomplete joins identifiers into one ambiguous value · case 01

The many completion transition produces an incorrect observable state.

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

ROOT CAUSE

At form-binding/many, the implementation evaluates `[[d['name'],','.join(d['values'])]]` instead of preserving the specified completion transition.

VERIFIED REPAIR

Implement the many contract using `[[d['name'],x] for x in d['values']]`.

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

Case contract

Form submission serializes committed suggestion identifiers separately from visible draft text. Required checks apply to committed values, an empty-string identifier is present, disabled fields are omitted, and reset restores the initial identity and label together. Multi-value fields preserve separate values.

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 == 'serialize': return d['value']
    if event == 'present': return d['value'] is not None
    if event == 'disabled': return [] if d['disabled'] else [[d['name'],d['value']]]
    if event == 'reset-id': return d['initial']
    if event == 'reset-label': return d['initial_label']
    if event == 'reset-baseline': return [d['initial'],d['initial_label']]
    if event == 'many': return [[d['name'],','.join(d['values'])]]
    if event == 'dirty': return d['draft']!=d['label']
    if event == 'display-field': return d['name']
    if event == 'reset-draft': return {'draft':d['initial_label'],'active':None}
    return {'unchanged': True}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'value':'p1','label':'Pear','draft':'peach','initial':'p0','initial_label':'Plum','name':'fruit','disabled':True,'required':True,'values':['a','b'],'epoch':N}
boundary = {'value':'','label':'','draft':'x','initial':None,'initial_label':'','name':'fruit','disabled':False,'required':True,'values':[],'epoch':N}
check('normal serialize', solve('serialize', normal), 'p1')
check('boundary serialize', solve('serialize', boundary), '')
check('normal present', solve('present', normal), True)
check('boundary present', solve('present', boundary), True)
check('normal disabled', solve('disabled', normal), [])
check('boundary disabled', solve('disabled', boundary), [['fruit','']])
check('normal reset-id', solve('reset-id', normal), 'p0')
check('boundary reset-id', solve('reset-id', boundary), None)
check('normal reset-label', solve('reset-label', normal), 'Plum')
check('boundary reset-label', solve('reset-label', boundary), '')
check('normal reset-baseline', solve('reset-baseline', normal), ['p0','Plum'])
check('boundary reset-baseline', solve('reset-baseline', boundary), [None,''])
check('normal many', solve('many', normal), [['fruit','a'],['fruit','b']])
check('boundary many', solve('many', boundary), [])
check('normal dirty', solve('dirty', normal), True)
check('boundary dirty', solve('dirty', boundary), True)
check('normal display-field', solve('display-field', normal), 'fruit')
check('boundary display-field', solve('display-field', boundary), 'fruit')
check('normal reset-draft', solve('reset-draft', normal), {'draft':'Plum','active':None})
check('boundary reset-draft', solve('reset-draft', boundary), {'draft':'','active':None})
variant = dict(normal, **{'value':'id'+str(N)})
check('variant query or selection payload', solve('serialize', variant), '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 fixtureActualExpectedOutcome
normal serializep1p1Passed
boundary serializePassed
normal presentTrueTruePassed
boundary presentTrueTruePassed
normal disabled[][]Passed
boundary disabled[['fruit', '']][['fruit', '']]Passed
normal reset-idp0p0Passed
boundary reset-idNoneNonePassed
normal reset-labelPlumPlumPassed
boundary reset-labelPassed
normal reset-baseline['p0', 'Plum']['p0', 'Plum']Passed
boundary reset-baseline[None, ''][None, '']Passed
normal many[['fruit', 'a,b']][['fruit', 'a'], ['fruit', 'b']]Failed
boundary many[['fruit', '']][]Failed
normal dirtyTrueTruePassed
boundary dirtyTrueTruePassed
normal display-fieldfruitfruitPassed
boundary display-fieldfruitfruitPassed
normal reset-draft{'active': None, 'draft': 'Plum'}{'active': None, 'draft': 'Plum'}Passed
boundary reset-draft{'active': None, 'draft': ''}{'active': None, 'draft': ''}Passed
variant query or selection payloadid1id1Passed
unknown completion event{'unchanged': True}{'unchanged': True}Passed

SHA-256 / a06a3394d8fa0cdafab7d5d84c6551dc9dd09a4b49eb8aa8ea449cd768f1ace7

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 == 'serialize': return d['value']
    if event == 'present': return d['value'] is not None
    if event == 'disabled': return [] if d['disabled'] else [[d['name'],d['value']]]
    if event == 'reset-id': return d['initial']
    if event == 'reset-label': return d['initial_label']
    if event == 'reset-baseline': return [d['initial'],d['initial_label']]
    if event == 'many': return [[d['name'],d['values']]]
    if event == 'dirty': return d['draft']!=d['label']
    if event == 'display-field': return d['name']
    if event == 'reset-draft': return {'draft':d['initial_label'],'active':None}
    return {'unchanged': True}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'value':'p1','label':'Pear','draft':'peach','initial':'p0','initial_label':'Plum','name':'fruit','disabled':True,'required':True,'values':['a','b'],'epoch':N}
boundary = {'value':'','label':'','draft':'x','initial':None,'initial_label':'','name':'fruit','disabled':False,'required':True,'values':[],'epoch':N}
check('normal serialize', solve('serialize', normal), 'p1')
check('boundary serialize', solve('serialize', boundary), '')
check('normal present', solve('present', normal), True)
check('boundary present', solve('present', boundary), True)
check('normal disabled', solve('disabled', normal), [])
check('boundary disabled', solve('disabled', boundary), [['fruit','']])
check('normal reset-id', solve('reset-id', normal), 'p0')
check('boundary reset-id', solve('reset-id', boundary), None)
check('normal reset-label', solve('reset-label', normal), 'Plum')
check('boundary reset-label', solve('reset-label', boundary), '')
check('normal reset-baseline', solve('reset-baseline', normal), ['p0','Plum'])
check('boundary reset-baseline', solve('reset-baseline', boundary), [None,''])
check('normal many', solve('many', normal), [['fruit','a'],['fruit','b']])
check('boundary many', solve('many', boundary), [])
check('normal dirty', solve('dirty', normal), True)
check('boundary dirty', solve('dirty', boundary), True)
check('normal display-field', solve('display-field', normal), 'fruit')
check('boundary display-field', solve('display-field', boundary), 'fruit')
check('normal reset-draft', solve('reset-draft', normal), {'draft':'Plum','active':None})
check('boundary reset-draft', solve('reset-draft', boundary), {'draft':'','active':None})
variant = dict(normal, **{'value':'id'+str(N)})
check('variant query or selection payload', solve('serialize', variant), '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 fixtureActualExpectedOutcome
normal serializep1p1Passed
boundary serializePassed
normal presentTrueTruePassed
boundary presentTrueTruePassed
normal disabled[][]Passed
boundary disabled[['fruit', '']][['fruit', '']]Passed
normal reset-idp0p0Passed
boundary reset-idNoneNonePassed
normal reset-labelPlumPlumPassed
boundary reset-labelPassed
normal reset-baseline['p0', 'Plum']['p0', 'Plum']Passed
boundary reset-baseline[None, ''][None, '']Passed
normal many[['fruit', ['a', 'b']]][['fruit', 'a'], ['fruit', 'b']]Failed
boundary many[['fruit', []]][]Failed
normal dirtyTrueTruePassed
boundary dirtyTrueTruePassed
normal display-fieldfruitfruitPassed
boundary display-fieldfruitfruitPassed
normal reset-draft{'active': None, 'draft': 'Plum'}{'active': None, 'draft': 'Plum'}Passed
boundary reset-draft{'active': None, 'draft': ''}{'active': None, 'draft': ''}Passed
variant query or selection payloadid1id1Passed
unknown completion event{'unchanged': True}{'unchanged': True}Passed

SHA-256 / d30b20218893d1eb5b4797c9e39cd9743af4090dbd2655baadcaaac6e89e26ef

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 == 'serialize': return d['value']
    if event == 'present': return d['value'] is not None
    if event == 'disabled': return [] if d['disabled'] else [[d['name'],d['value']]]
    if event == 'reset-id': return d['initial']
    if event == 'reset-label': return d['initial_label']
    if event == 'reset-baseline': return [d['initial'],d['initial_label']]
    if event == 'many': return [[d['name'],x] for x in d['values']]
    if event == 'dirty': return d['draft']!=d['label']
    if event == 'display-field': return d['name']
    if event == 'reset-draft': return {'draft':d['initial_label'],'active':None}
    return {'unchanged': True}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
normal = {'value':'p1','label':'Pear','draft':'peach','initial':'p0','initial_label':'Plum','name':'fruit','disabled':True,'required':True,'values':['a','b'],'epoch':N}
boundary = {'value':'','label':'','draft':'x','initial':None,'initial_label':'','name':'fruit','disabled':False,'required':True,'values':[],'epoch':N}
check('normal serialize', solve('serialize', normal), 'p1')
check('boundary serialize', solve('serialize', boundary), '')
check('normal present', solve('present', normal), True)
check('boundary present', solve('present', boundary), True)
check('normal disabled', solve('disabled', normal), [])
check('boundary disabled', solve('disabled', boundary), [['fruit','']])
check('normal reset-id', solve('reset-id', normal), 'p0')
check('boundary reset-id', solve('reset-id', boundary), None)
check('normal reset-label', solve('reset-label', normal), 'Plum')
check('boundary reset-label', solve('reset-label', boundary), '')
check('normal reset-baseline', solve('reset-baseline', normal), ['p0','Plum'])
check('boundary reset-baseline', solve('reset-baseline', boundary), [None,''])
check('normal many', solve('many', normal), [['fruit','a'],['fruit','b']])
check('boundary many', solve('many', boundary), [])
check('normal dirty', solve('dirty', normal), True)
check('boundary dirty', solve('dirty', boundary), True)
check('normal display-field', solve('display-field', normal), 'fruit')
check('boundary display-field', solve('display-field', boundary), 'fruit')
check('normal reset-draft', solve('reset-draft', normal), {'draft':'Plum','active':None})
check('boundary reset-draft', solve('reset-draft', boundary), {'draft':'','active':None})
variant = dict(normal, **{'value':'id'+str(N)})
check('variant query or selection payload', solve('serialize', variant), '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 fixtureActualExpectedOutcome
normal serializep1p1Passed
boundary serializePassed
normal presentTrueTruePassed
boundary presentTrueTruePassed
normal disabled[][]Passed
boundary disabled[['fruit', '']][['fruit', '']]Passed
normal reset-idp0p0Passed
boundary reset-idNoneNonePassed
normal reset-labelPlumPlumPassed
boundary reset-labelPassed
normal reset-baseline['p0', 'Plum']['p0', 'Plum']Passed
boundary reset-baseline[None, ''][None, '']Passed
normal many[['fruit', 'a'], ['fruit', 'b']][['fruit', 'a'], ['fruit', 'b']]Passed
boundary many[][]Passed
normal dirtyTrueTruePassed
boundary dirtyTrueTruePassed
normal display-fieldfruitfruitPassed
boundary display-fieldfruitfruitPassed
normal reset-draft{'active': None, 'draft': 'Plum'}{'active': None, 'draft': 'Plum'}Passed
boundary reset-draft{'active': None, 'draft': ''}{'active': None, 'draft': ''}Passed
variant query or selection payloadid1id1Passed
unknown completion event{'unchanged': True}{'unchanged': True}Passed

SHA-256 / 7b2e0111c24d33e8494a16d4f7b0a0783a354775d54d5ef60d60d650c8a24af4

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 2026-09-29T14:40:41.562038+00:00.

Case digest / f90abcf65ff0f5fdb7be454bfdd181b8a9c8e2a7e9170cd2002f0dc21c3a03b3