FAILURE MAP
← Case archive

FA-24806 / Client state / Open access

A new navigation inherits transient route-state notices from the previous entry · case 01

A new navigation inherits transient route-state notices from the previous entry.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The faulty implementation violates The stipulated navigation state policy preserves all entry-local state on pop, but push/replace carry forward only declared persistent keys including null/falsy values.

VERIFIED REPAIR

The stipulated navigation state policy preserves all entry-local state on pop, but push/replace carry forward only declared persistent keys including null/falsy values.

Unsuccessful approach: The partial repair still violates at least one explicit regression oracle.

Case contract

The stipulated navigation state policy preserves all entry-local state on pop, but push/replace carry forward only declared persistent keys including null/falsy values.

Why this case matters

A bounded offline client-state transition with explicit lifecycle inputs.

1 / The failure

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

N = 1
observations = []
def solve(state, persistent, event):
    return dict(state)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('push drops transient', solve({'notice':'saved','context':N},['context'],'push'), {'context':N})
check('pop restores transient', solve({'notice':'saved','context':N},['context'],'pop'), {'notice':'saved','context':N})
check('replace cleans', solve({'notice':''},[],'replace'), {})
check('persistent null', solve({'context':None},['context'],'push'), {'context':None})
check('unknown persistent key', solve({'notice':'x'},['missing'],'push'), {})
check('empty state', solve({},['context'],'pop'), {})
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
push drops transient{'context': 1, 'notice': 'saved'}{'context': 1}Failed
pop restores transient{'context': 1, 'notice': 'saved'}{'context': 1, 'notice': 'saved'}Passed
replace cleans{'notice': ''}{}Failed
persistent null{'context': None}{'context': None}Passed
unknown persistent key{'notice': 'x'}{}Failed
empty state{}{}Passed

SHA-256 / f717cba89af5318379f924c53e9ac84a79ca0a3126a0d01da35e0da0fa4f12b7

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(state, persistent, event):
    return {k:v for k,v in state.items() if k in persistent}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('push drops transient', solve({'notice':'saved','context':N},['context'],'push'), {'context':N})
check('pop restores transient', solve({'notice':'saved','context':N},['context'],'pop'), {'notice':'saved','context':N})
check('replace cleans', solve({'notice':''},[],'replace'), {})
check('persistent null', solve({'context':None},['context'],'push'), {'context':None})
check('unknown persistent key', solve({'notice':'x'},['missing'],'push'), {})
check('empty state', solve({},['context'],'pop'), {})
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
push drops transient{'context': 1}{'context': 1}Passed
pop restores transient{'context': 1}{'context': 1, 'notice': 'saved'}Failed
replace cleans{}{}Passed
persistent null{'context': None}{'context': None}Passed
unknown persistent key{}{}Passed
empty state{}{}Passed

SHA-256 / 7e0e2caa2f9c832503bebac04723aee3e7881af3d7004ff232ec84c40bd5ea3e

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(state, persistent, event):
    return dict(state) if event=='pop' else {k:v for k,v in state.items() if k in persistent}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('push drops transient', solve({'notice':'saved','context':N},['context'],'push'), {'context':N})
check('pop restores transient', solve({'notice':'saved','context':N},['context'],'pop'), {'notice':'saved','context':N})
check('replace cleans', solve({'notice':''},[],'replace'), {})
check('persistent null', solve({'context':None},['context'],'push'), {'context':None})
check('unknown persistent key', solve({'notice':'x'},['missing'],'push'), {})
check('empty state', solve({},['context'],'pop'), {})
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
push drops transient{'context': 1}{'context': 1}Passed
pop restores transient{'context': 1, 'notice': 'saved'}{'context': 1, 'notice': 'saved'}Passed
replace cleans{}{}Passed
persistent null{'context': None}{'context': None}Passed
unknown persistent key{}{}Passed
empty state{}{}Passed

SHA-256 / b9498b43845e3ef47263651c1439247a9bc6a73deae159591cd3c27b97b76989

Verification & scope

This models the stated application policy only; 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 2026-09-29T14:41:00.906666+00:00.

Case digest / 20078ac2832de269439999adefae2b6b71f71161b87cb70a080eb7bf002235c1