FA-24721 / Client state / Open access
A nested route failure clears unrelated loaded segments · case 01
A nested route failure clears unrelated loaded segments.
ROOT CAUSE
The faulty implementation violates An error replaces only the matching route segment state with an error/data pair; siblings and unknown segment IDs are unchanged.
VERIFIED REPAIR
An error replaces only the matching route segment state with an error/data pair; siblings and unknown segment IDs are unchanged.
Unsuccessful approach: The partial repair still violates at least one explicit regression oracle.
Case contract
An error replaces only the matching route segment state with an error/data pair; siblings and unknown segment IDs are unchanged.
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(segments, failed_segment, error):
return {k:{'error':error,'data':None} for k in segments}
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('nested child', solve({'layout':{'data':N},'child':{'data':2}},'child','bad'), {'layout':{'data':N},'child':{'error':'bad','data':None}})
check('layout failure', solve({'layout':{'data':N},'child':{'data':2}},'layout','bad'), {'layout':{'error':'bad','data':None},'child':{'data':2}})
check('unknown segment', solve({'layout':{'data':N}},'gone','bad'), {'layout':{'data':N}})
check('empty tree', solve({},'child','bad'), {})
check('null failure payload', solve({'child':{'data':N}},'child',None), {'child':{'error':None,'data':None}})
check('empty error text', solve({'child':{'data':N},'side':{}},'child',''), {'child':{'error':'','data':None},'side':{}})
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 |
|---|---|---|---|
| nested child | {'child': {'data': None, 'error': 'bad'}, 'layout': {'data': None, 'error': 'bad'}} | {'child': {'data': None, 'error': 'bad'}, 'layout': {'data': 1}} | Failed |
| layout failure | {'child': {'data': None, 'error': 'bad'}, 'layout': {'data': None, 'error': 'bad'}} | {'child': {'data': 2}, 'layout': {'data': None, 'error': 'bad'}} | Failed |
| unknown segment | {'layout': {'data': None, 'error': 'bad'}} | {'layout': {'data': 1}} | Failed |
| empty tree | {} | {} | Passed |
| null failure payload | {'child': {'data': None, 'error': None}} | {'child': {'data': None, 'error': None}} | Passed |
| empty error text | {'child': {'data': None, 'error': ''}, 'side': {'data': None, 'error': ''}} | {'child': {'data': None, 'error': ''}, 'side': {}} | Failed |
SHA-256 / 88871a427275415ad8be8c7025f4216414c801a269e04c7abf51351eda49c26b
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(segments, failed_segment, error):
return {k:v for k,v in segments.items() if k!=failed_segment}
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('nested child', solve({'layout':{'data':N},'child':{'data':2}},'child','bad'), {'layout':{'data':N},'child':{'error':'bad','data':None}})
check('layout failure', solve({'layout':{'data':N},'child':{'data':2}},'layout','bad'), {'layout':{'error':'bad','data':None},'child':{'data':2}})
check('unknown segment', solve({'layout':{'data':N}},'gone','bad'), {'layout':{'data':N}})
check('empty tree', solve({},'child','bad'), {})
check('null failure payload', solve({'child':{'data':N}},'child',None), {'child':{'error':None,'data':None}})
check('empty error text', solve({'child':{'data':N},'side':{}},'child',''), {'child':{'error':'','data':None},'side':{}})
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 |
|---|---|---|---|
| nested child | {'layout': {'data': 1}} | {'child': {'data': None, 'error': 'bad'}, 'layout': {'data': 1}} | Failed |
| layout failure | {'child': {'data': 2}} | {'child': {'data': 2}, 'layout': {'data': None, 'error': 'bad'}} | Failed |
| unknown segment | {'layout': {'data': 1}} | {'layout': {'data': 1}} | Passed |
| empty tree | {} | {} | Passed |
| null failure payload | {} | {'child': {'data': None, 'error': None}} | Failed |
| empty error text | {'side': {}} | {'child': {'data': None, 'error': ''}, 'side': {}} | Failed |
SHA-256 / 610aeff009f7f4daa0acaf93634c716102dca4f49fe2345c52b7c848b189f051
3 / The verified repair
Exit 0"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(segments, failed_segment, error):
return {k:({'error':error,'data':None} if k==failed_segment else v) for k,v in segments.items()}
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('nested child', solve({'layout':{'data':N},'child':{'data':2}},'child','bad'), {'layout':{'data':N},'child':{'error':'bad','data':None}})
check('layout failure', solve({'layout':{'data':N},'child':{'data':2}},'layout','bad'), {'layout':{'error':'bad','data':None},'child':{'data':2}})
check('unknown segment', solve({'layout':{'data':N}},'gone','bad'), {'layout':{'data':N}})
check('empty tree', solve({},'child','bad'), {})
check('null failure payload', solve({'child':{'data':N}},'child',None), {'child':{'error':None,'data':None}})
check('empty error text', solve({'child':{'data':N},'side':{}},'child',''), {'child':{'error':'','data':None},'side':{}})
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 |
|---|---|---|---|
| nested child | {'child': {'data': None, 'error': 'bad'}, 'layout': {'data': 1}} | {'child': {'data': None, 'error': 'bad'}, 'layout': {'data': 1}} | Passed |
| layout failure | {'child': {'data': 2}, 'layout': {'data': None, 'error': 'bad'}} | {'child': {'data': 2}, 'layout': {'data': None, 'error': 'bad'}} | Passed |
| unknown segment | {'layout': {'data': 1}} | {'layout': {'data': 1}} | Passed |
| empty tree | {} | {} | Passed |
| null failure payload | {'child': {'data': None, 'error': None}} | {'child': {'data': None, 'error': None}} | Passed |
| empty error text | {'child': {'data': None, 'error': ''}, 'side': {}} | {'child': {'data': None, 'error': ''}, 'side': {}} | Passed |
SHA-256 / 8db4c78ff3c2fb3b0c73f0dff1f919992607d5bd8bb110b0f8ea47ef8763eeb9
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 2026-09-29T14:41:00.033731+00:00.
Case digest / afb7f3bf2e0404a9febaf1c34c2cc1f7e9691b63621fd6f30699657e51b605cf