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FA-23551 / Client state / Open access

Persisted client snapshot admission: Missing default identification · case 01

Missing default identification.

Verified by executionVariant 1 · 60 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The missing-default-identification client decision evaluates `sorted(defaults)` instead of `sorted(set(defaults)-set(stored))`.

THE FAILURE

The missing-default-identification client decision evaluates `sorted(defaults)` instead of `sorted(set(defaults)-set(stored))`.

Unsuccessful approach: The partial repair `sorted(k for k in defaults if not stored.get(k))` still violates the explicit fixture contract.

Case contract

Persist only declared nontransient keys. Missing defaults are filled without replacing null/falsy data. Older schema versions migrate through each intermediate step; future versions stay read-only and keep their version stamp. Operation missing-default-identification has the six explicit input/output oracles below.

Why this case matters

An offline client lifecycle model that isolates a state-management defect without DOM rendering or network services.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(operation, s):
    stored, version, current, allowed, defaults, transient = s
    if operation == 'unknown-field-projection':
        return {k:v for k,v in stored.items() if k in allowed}
    if operation == 'default-overlay-order':
        return {**defaults,**stored}
    if operation == 'future-version-readonly':
        return version>current
    if operation == 'migration-step-list':
        return list(range(version,current)) if version<=current else []
    if operation == 'transient-exclusion':
        return {k:v for k,v in stored.items() if k not in transient}
    if operation == 'missing-default-identification':
        return sorted(defaults)
    if operation == 'nullable-persisted-value':
        return stored['a'] if 'a' in stored else defaults.get('a')
    if operation == 'write-version-stamp':
        return max(version,current)
    if operation == 'schema-fallback-policy':
        return 'read-only' if version>current else ('migrate' if version<current else 'load')
    if operation == 'serialized-field-order':
        return sorted(k for k in stored if k in allowed and k not in transient)
    raise ValueError('unknown modeled operation')
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('unknown-field-projection scenario 1', solve('unknown-field-projection', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), {'a':N,'b':False})
check('unknown-field-projection scenario 2', solve('unknown-field-projection', ({},2,2,['a'],{'a':N},[])), {})
check('unknown-field-projection scenario 3', solve('unknown-field-projection', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), {'a':None})
check('unknown-field-projection scenario 4', solve('unknown-field-projection', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), {'b':N})
check('unknown-field-projection scenario 5', solve('unknown-field-projection', ({'a':'','b':True},2,2,[],{},[])), {})
check('unknown-field-projection scenario 6', solve('unknown-field-projection', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), {'a':N})
check('default-overlay-order scenario 1', solve('default-overlay-order', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), {'a':N,'b':False,'temp':7})
check('default-overlay-order scenario 2', solve('default-overlay-order', ({},2,2,['a'],{'a':N},[])), {'a':N})
check('default-overlay-order scenario 3', solve('default-overlay-order', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), {'a':None,'extra':1})
check('default-overlay-order scenario 4', solve('default-overlay-order', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), {'b':N,'a':0})
check('default-overlay-order scenario 5', solve('default-overlay-order', ({'a':'','b':True},2,2,[],{},[])), {'a':'','b':True})
check('default-overlay-order scenario 6', solve('default-overlay-order', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), {'a':N,'temp':1})
check('future-version-readonly scenario 1', solve('future-version-readonly', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), False)
check('future-version-readonly scenario 2', solve('future-version-readonly', ({},2,2,['a'],{'a':N},[])), False)
check('future-version-readonly scenario 3', solve('future-version-readonly', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), True)
check('future-version-readonly scenario 4', solve('future-version-readonly', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), False)
check('future-version-readonly scenario 5', solve('future-version-readonly', ({'a':'','b':True},2,2,[],{},[])), False)
check('future-version-readonly scenario 6', solve('future-version-readonly', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), False)
check('migration-step-list scenario 1', solve('migration-step-list', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), [1])
check('migration-step-list scenario 2', solve('migration-step-list', ({},2,2,['a'],{'a':N},[])), [])
check('migration-step-list scenario 3', solve('migration-step-list', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), [])
check('migration-step-list scenario 4', solve('migration-step-list', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), [0,1])
check('migration-step-list scenario 5', solve('migration-step-list', ({'a':'','b':True},2,2,[],{},[])), [])
check('migration-step-list scenario 6', solve('migration-step-list', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), [])
check('transient-exclusion scenario 1', solve('transient-exclusion', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), {'a':N,'b':False})
check('transient-exclusion scenario 2', solve('transient-exclusion', ({},2,2,['a'],{'a':N},[])), {})
check('transient-exclusion scenario 3', solve('transient-exclusion', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), {'a':None})
check('transient-exclusion scenario 4', solve('transient-exclusion', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), {'b':N})
check('transient-exclusion scenario 5', solve('transient-exclusion', ({'a':'','b':True},2,2,[],{},[])), {'a':'','b':True})
check('transient-exclusion scenario 6', solve('transient-exclusion', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), {'a':N})
check('missing-default-identification scenario 1', solve('missing-default-identification', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), [])
check('missing-default-identification scenario 2', solve('missing-default-identification', ({},2,2,['a'],{'a':N},[])), ['a'])
check('missing-default-identification scenario 3', solve('missing-default-identification', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), [])
check('missing-default-identification scenario 4', solve('missing-default-identification', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), [])
check('missing-default-identification scenario 5', solve('missing-default-identification', ({'a':'','b':True},2,2,[],{},[])), [])
check('missing-default-identification scenario 6', solve('missing-default-identification', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), [])
check('nullable-persisted-value scenario 1', solve('nullable-persisted-value', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), N)
check('nullable-persisted-value scenario 2', solve('nullable-persisted-value', ({},2,2,['a'],{'a':N},[])), N)
check('nullable-persisted-value scenario 3', solve('nullable-persisted-value', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), None)
check('nullable-persisted-value scenario 4', solve('nullable-persisted-value', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), 0)
check('nullable-persisted-value scenario 5', solve('nullable-persisted-value', ({'a':'','b':True},2,2,[],{},[])), '')
check('nullable-persisted-value scenario 6', solve('nullable-persisted-value', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), N)
check('write-version-stamp scenario 1', solve('write-version-stamp', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), 2)
check('write-version-stamp scenario 2', solve('write-version-stamp', ({},2,2,['a'],{'a':N},[])), 2)
check('write-version-stamp scenario 3', solve('write-version-stamp', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), 3)
check('write-version-stamp scenario 4', solve('write-version-stamp', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), 2)
check('write-version-stamp scenario 5', solve('write-version-stamp', ({'a':'','b':True},2,2,[],{},[])), 2)
check('write-version-stamp scenario 6', solve('write-version-stamp', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), 1)
check('schema-fallback-policy scenario 1', solve('schema-fallback-policy', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), 'migrate')
check('schema-fallback-policy scenario 2', solve('schema-fallback-policy', ({},2,2,['a'],{'a':N},[])), 'load')
check('schema-fallback-policy scenario 3', solve('schema-fallback-policy', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), 'read-only')
check('schema-fallback-policy scenario 4', solve('schema-fallback-policy', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), 'migrate')
check('schema-fallback-policy scenario 5', solve('schema-fallback-policy', ({'a':'','b':True},2,2,[],{},[])), 'load')
check('schema-fallback-policy scenario 6', solve('schema-fallback-policy', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), 'load')
check('serialized-field-order scenario 1', solve('serialized-field-order', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), ['a','b'])
check('serialized-field-order scenario 2', solve('serialized-field-order', ({},2,2,['a'],{'a':N},[])), [])
check('serialized-field-order scenario 3', solve('serialized-field-order', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), ['a'])
check('serialized-field-order scenario 4', solve('serialized-field-order', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), ['b'])
check('serialized-field-order scenario 5', solve('serialized-field-order', ({'a':'','b':True},2,2,[],{},[])), [])
check('serialized-field-order scenario 6', solve('serialized-field-order', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), ['a'])
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
unknown-field-projection scenario 1{'a': 1, 'b': False}{'a': 1, 'b': False}Passed
unknown-field-projection scenario 2{}{}Passed
unknown-field-projection scenario 3{'a': None}{'a': None}Passed
unknown-field-projection scenario 4{'b': 1}{'b': 1}Passed
unknown-field-projection scenario 5{}{}Passed
unknown-field-projection scenario 6{'a': 1}{'a': 1}Passed
default-overlay-order scenario 1{'a': 1, 'b': False, 'temp': 7}{'a': 1, 'b': False, 'temp': 7}Passed
default-overlay-order scenario 2{'a': 1}{'a': 1}Passed
default-overlay-order scenario 3{'a': None, 'extra': 1}{'a': None, 'extra': 1}Passed
default-overlay-order scenario 4{'a': 0, 'b': 1}{'a': 0, 'b': 1}Passed
default-overlay-order scenario 5{'a': '', 'b': True}{'a': '', 'b': True}Passed
default-overlay-order scenario 6{'a': 1, 'temp': 1}{'a': 1, 'temp': 1}Passed
future-version-readonly scenario 1FalseFalsePassed
future-version-readonly scenario 2FalseFalsePassed
future-version-readonly scenario 3TrueTruePassed
future-version-readonly scenario 4FalseFalsePassed
future-version-readonly scenario 5FalseFalsePassed
future-version-readonly scenario 6FalseFalsePassed
migration-step-list scenario 1[1][1]Passed
migration-step-list scenario 2[][]Passed
migration-step-list scenario 3[][]Passed
migration-step-list scenario 4[0, 1][0, 1]Passed
migration-step-list scenario 5[][]Passed
migration-step-list scenario 6[][]Passed
transient-exclusion scenario 1{'a': 1, 'b': False}{'a': 1, 'b': False}Passed
transient-exclusion scenario 2{}{}Passed
transient-exclusion scenario 3{'a': None}{'a': None}Passed
transient-exclusion scenario 4{'b': 1}{'b': 1}Passed
transient-exclusion scenario 5{'a': '', 'b': True}{'a': '', 'b': True}Passed
transient-exclusion scenario 6{'a': 1}{'a': 1}Passed
missing-default-identification scenario 1['a', 'b'][]Failed
missing-default-identification scenario 2['a']['a']Passed
missing-default-identification scenario 3['a'][]Failed
missing-default-identification scenario 4['b'][]Failed
missing-default-identification scenario 5[][]Passed
missing-default-identification scenario 6[][]Passed
nullable-persisted-value scenario 111Passed
nullable-persisted-value scenario 211Passed
nullable-persisted-value scenario 3NoneNonePassed
nullable-persisted-value scenario 400Passed
nullable-persisted-value scenario 5Passed
nullable-persisted-value scenario 611Passed
write-version-stamp scenario 122Passed
write-version-stamp scenario 222Passed
write-version-stamp scenario 333Passed
write-version-stamp scenario 422Passed
write-version-stamp scenario 522Passed
write-version-stamp scenario 611Passed
schema-fallback-policy scenario 1migratemigratePassed
schema-fallback-policy scenario 2loadloadPassed
schema-fallback-policy scenario 3read-onlyread-onlyPassed
schema-fallback-policy scenario 4migratemigratePassed
schema-fallback-policy scenario 5loadloadPassed
schema-fallback-policy scenario 6loadloadPassed
serialized-field-order scenario 1['a', 'b']['a', 'b']Passed
serialized-field-order scenario 2[][]Passed
serialized-field-order scenario 3['a']['a']Passed
serialized-field-order scenario 4['b']['b']Passed
serialized-field-order scenario 5[][]Passed
serialized-field-order scenario 6['a']['a']Passed

SHA-256 / 92dfdbf035c558dd2eb2e5c8a5539cd46be2292879f49d8ae82d7a45c25bf0c7

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(operation, s):
    stored, version, current, allowed, defaults, transient = s
    if operation == 'unknown-field-projection':
        return {k:v for k,v in stored.items() if k in allowed}
    if operation == 'default-overlay-order':
        return {**defaults,**stored}
    if operation == 'future-version-readonly':
        return version>current
    if operation == 'migration-step-list':
        return list(range(version,current)) if version<=current else []
    if operation == 'transient-exclusion':
        return {k:v for k,v in stored.items() if k not in transient}
    if operation == 'missing-default-identification':
        return sorted(k for k in defaults if not stored.get(k))
    if operation == 'nullable-persisted-value':
        return stored['a'] if 'a' in stored else defaults.get('a')
    if operation == 'write-version-stamp':
        return max(version,current)
    if operation == 'schema-fallback-policy':
        return 'read-only' if version>current else ('migrate' if version<current else 'load')
    if operation == 'serialized-field-order':
        return sorted(k for k in stored if k in allowed and k not in transient)
    raise ValueError('unknown modeled operation')
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('unknown-field-projection scenario 1', solve('unknown-field-projection', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), {'a':N,'b':False})
check('unknown-field-projection scenario 2', solve('unknown-field-projection', ({},2,2,['a'],{'a':N},[])), {})
check('unknown-field-projection scenario 3', solve('unknown-field-projection', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), {'a':None})
check('unknown-field-projection scenario 4', solve('unknown-field-projection', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), {'b':N})
check('unknown-field-projection scenario 5', solve('unknown-field-projection', ({'a':'','b':True},2,2,[],{},[])), {})
check('unknown-field-projection scenario 6', solve('unknown-field-projection', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), {'a':N})
check('default-overlay-order scenario 1', solve('default-overlay-order', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), {'a':N,'b':False,'temp':7})
check('default-overlay-order scenario 2', solve('default-overlay-order', ({},2,2,['a'],{'a':N},[])), {'a':N})
check('default-overlay-order scenario 3', solve('default-overlay-order', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), {'a':None,'extra':1})
check('default-overlay-order scenario 4', solve('default-overlay-order', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), {'b':N,'a':0})
check('default-overlay-order scenario 5', solve('default-overlay-order', ({'a':'','b':True},2,2,[],{},[])), {'a':'','b':True})
check('default-overlay-order scenario 6', solve('default-overlay-order', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), {'a':N,'temp':1})
check('future-version-readonly scenario 1', solve('future-version-readonly', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), False)
check('future-version-readonly scenario 2', solve('future-version-readonly', ({},2,2,['a'],{'a':N},[])), False)
check('future-version-readonly scenario 3', solve('future-version-readonly', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), True)
check('future-version-readonly scenario 4', solve('future-version-readonly', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), False)
check('future-version-readonly scenario 5', solve('future-version-readonly', ({'a':'','b':True},2,2,[],{},[])), False)
check('future-version-readonly scenario 6', solve('future-version-readonly', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), False)
check('migration-step-list scenario 1', solve('migration-step-list', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), [1])
check('migration-step-list scenario 2', solve('migration-step-list', ({},2,2,['a'],{'a':N},[])), [])
check('migration-step-list scenario 3', solve('migration-step-list', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), [])
check('migration-step-list scenario 4', solve('migration-step-list', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), [0,1])
check('migration-step-list scenario 5', solve('migration-step-list', ({'a':'','b':True},2,2,[],{},[])), [])
check('migration-step-list scenario 6', solve('migration-step-list', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), [])
check('transient-exclusion scenario 1', solve('transient-exclusion', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), {'a':N,'b':False})
check('transient-exclusion scenario 2', solve('transient-exclusion', ({},2,2,['a'],{'a':N},[])), {})
check('transient-exclusion scenario 3', solve('transient-exclusion', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), {'a':None})
check('transient-exclusion scenario 4', solve('transient-exclusion', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), {'b':N})
check('transient-exclusion scenario 5', solve('transient-exclusion', ({'a':'','b':True},2,2,[],{},[])), {'a':'','b':True})
check('transient-exclusion scenario 6', solve('transient-exclusion', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), {'a':N})
check('missing-default-identification scenario 1', solve('missing-default-identification', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), [])
check('missing-default-identification scenario 2', solve('missing-default-identification', ({},2,2,['a'],{'a':N},[])), ['a'])
check('missing-default-identification scenario 3', solve('missing-default-identification', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), [])
check('missing-default-identification scenario 4', solve('missing-default-identification', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), [])
check('missing-default-identification scenario 5', solve('missing-default-identification', ({'a':'','b':True},2,2,[],{},[])), [])
check('missing-default-identification scenario 6', solve('missing-default-identification', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), [])
check('nullable-persisted-value scenario 1', solve('nullable-persisted-value', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), N)
check('nullable-persisted-value scenario 2', solve('nullable-persisted-value', ({},2,2,['a'],{'a':N},[])), N)
check('nullable-persisted-value scenario 3', solve('nullable-persisted-value', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), None)
check('nullable-persisted-value scenario 4', solve('nullable-persisted-value', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), 0)
check('nullable-persisted-value scenario 5', solve('nullable-persisted-value', ({'a':'','b':True},2,2,[],{},[])), '')
check('nullable-persisted-value scenario 6', solve('nullable-persisted-value', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), N)
check('write-version-stamp scenario 1', solve('write-version-stamp', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), 2)
check('write-version-stamp scenario 2', solve('write-version-stamp', ({},2,2,['a'],{'a':N},[])), 2)
check('write-version-stamp scenario 3', solve('write-version-stamp', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), 3)
check('write-version-stamp scenario 4', solve('write-version-stamp', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), 2)
check('write-version-stamp scenario 5', solve('write-version-stamp', ({'a':'','b':True},2,2,[],{},[])), 2)
check('write-version-stamp scenario 6', solve('write-version-stamp', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), 1)
check('schema-fallback-policy scenario 1', solve('schema-fallback-policy', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), 'migrate')
check('schema-fallback-policy scenario 2', solve('schema-fallback-policy', ({},2,2,['a'],{'a':N},[])), 'load')
check('schema-fallback-policy scenario 3', solve('schema-fallback-policy', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), 'read-only')
check('schema-fallback-policy scenario 4', solve('schema-fallback-policy', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), 'migrate')
check('schema-fallback-policy scenario 5', solve('schema-fallback-policy', ({'a':'','b':True},2,2,[],{},[])), 'load')
check('schema-fallback-policy scenario 6', solve('schema-fallback-policy', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), 'load')
check('serialized-field-order scenario 1', solve('serialized-field-order', ({'a':N,'b':False,'temp':7},1,2,['a','b'],{'a':0,'b':True},['temp'])), ['a','b'])
check('serialized-field-order scenario 2', solve('serialized-field-order', ({},2,2,['a'],{'a':N},[])), [])
check('serialized-field-order scenario 3', solve('serialized-field-order', ({'a':None,'extra':1},3,2,['a'],{'a':N},['extra'])), ['a'])
check('serialized-field-order scenario 4', solve('serialized-field-order', ({'a':0,'b':N},0,2,['b'],{'b':9},['a'])), ['b'])
check('serialized-field-order scenario 5', solve('serialized-field-order', ({'a':'','b':True},2,2,[],{},[])), [])
check('serialized-field-order scenario 6', solve('serialized-field-order', ({'a':N,'temp':1},1,1,['a'],{},['temp'])), ['a'])
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
unknown-field-projection scenario 1{'a': 1, 'b': False}{'a': 1, 'b': False}Passed
unknown-field-projection scenario 2{}{}Passed
unknown-field-projection scenario 3{'a': None}{'a': None}Passed
unknown-field-projection scenario 4{'b': 1}{'b': 1}Passed
unknown-field-projection scenario 5{}{}Passed
unknown-field-projection scenario 6{'a': 1}{'a': 1}Passed
default-overlay-order scenario 1{'a': 1, 'b': False, 'temp': 7}{'a': 1, 'b': False, 'temp': 7}Passed
default-overlay-order scenario 2{'a': 1}{'a': 1}Passed
default-overlay-order scenario 3{'a': None, 'extra': 1}{'a': None, 'extra': 1}Passed
default-overlay-order scenario 4{'a': 0, 'b': 1}{'a': 0, 'b': 1}Passed
default-overlay-order scenario 5{'a': '', 'b': True}{'a': '', 'b': True}Passed
default-overlay-order scenario 6{'a': 1, 'temp': 1}{'a': 1, 'temp': 1}Passed
future-version-readonly scenario 1FalseFalsePassed
future-version-readonly scenario 2FalseFalsePassed
future-version-readonly scenario 3TrueTruePassed
future-version-readonly scenario 4FalseFalsePassed
future-version-readonly scenario 5FalseFalsePassed
future-version-readonly scenario 6FalseFalsePassed
migration-step-list scenario 1[1][1]Passed
migration-step-list scenario 2[][]Passed
migration-step-list scenario 3[][]Passed
migration-step-list scenario 4[0, 1][0, 1]Passed
migration-step-list scenario 5[][]Passed
migration-step-list scenario 6[][]Passed
transient-exclusion scenario 1{'a': 1, 'b': False}{'a': 1, 'b': False}Passed
transient-exclusion scenario 2{}{}Passed
transient-exclusion scenario 3{'a': None}{'a': None}Passed
transient-exclusion scenario 4{'b': 1}{'b': 1}Passed
transient-exclusion scenario 5{'a': '', 'b': True}{'a': '', 'b': True}Passed
transient-exclusion scenario 6{'a': 1}{'a': 1}Passed
missing-default-identification scenario 1['b'][]Failed
missing-default-identification scenario 2['a']['a']Passed
missing-default-identification scenario 3['a'][]Failed
missing-default-identification scenario 4[][]Passed
missing-default-identification scenario 5[][]Passed
missing-default-identification scenario 6[][]Passed
nullable-persisted-value scenario 111Passed
nullable-persisted-value scenario 211Passed
nullable-persisted-value scenario 3NoneNonePassed
nullable-persisted-value scenario 400Passed
nullable-persisted-value scenario 5Passed
nullable-persisted-value scenario 611Passed
write-version-stamp scenario 122Passed
write-version-stamp scenario 222Passed
write-version-stamp scenario 333Passed
write-version-stamp scenario 422Passed
write-version-stamp scenario 522Passed
write-version-stamp scenario 611Passed
schema-fallback-policy scenario 1migratemigratePassed
schema-fallback-policy scenario 2loadloadPassed
schema-fallback-policy scenario 3read-onlyread-onlyPassed
schema-fallback-policy scenario 4migratemigratePassed
schema-fallback-policy scenario 5loadloadPassed
schema-fallback-policy scenario 6loadloadPassed
serialized-field-order scenario 1['a', 'b']['a', 'b']Passed
serialized-field-order scenario 2[][]Passed
serialized-field-order scenario 3['a']['a']Passed
serialized-field-order scenario 4['b']['b']Passed
serialized-field-order scenario 5[][]Passed
serialized-field-order scenario 6['a']['a']Passed

SHA-256 / 738f154c4776cd23b7d5796d7d8236ea8aa2512eec21874748530fd8242c5d5f

HELD IN THE MEMBER ARCHIVE

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

This mechanism has 60 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.

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Verification & scope

Only the explicitly specified operations and finite deterministic records are modeled; no browser or framework conformance is claimed. 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 2026-09-29T14:40:49.036390+00:00.

Case digest / 55d67b8dc131a2d4218c3c0490d14979d9c9c89b8448df9fe71bb113eb70b793