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FA-7196 / Network routing / Open access

Route table refresh replaces removed routes · case 01

Route table refresh replaces removed routes.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The faulty implementation uses `dict(old,**new)` for the route-table-refresh-replaces-removed-routes decision.

VERIFIED REPAIR

Apply the explicit route-table-refresh-replaces-removed-routes contract, including the tested boundary and negative cases.

Unsuccessful approach: The attempted repair uses `{k:v for k,v in old.items() if k in new}` and still violates a separate fixture.

Case contract

Bounded offline decision model: route table refresh replaces removed routes. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.

Why this case matters

This deterministic network routing model isolates the route-table-refresh-replaces-removed-routes policy at a network component boundary.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(old, new):
    return dict(old,**new)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve({'a': 1, 'b': 2}, {'a': 3}), {'a': 3})", "check('fixture 2', solve({}, {'b': 2}), {'b': 2})", "check('fixture 3', solve({'a': 1}, {}), {})", "check('fixture 4', solve({}, {}), {})"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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
fixture 2{'b': 2}{'b': 2}Passed
fixture 3{'a': 1}{}Failed
fixture 4{}{}Passed
fixture 1{'a': 3, 'b': 2}{'a': 3}Failed

SHA-256 / 67645ed01f748b7b649993c15f5104c44a1963dad4fce4fd9cfbe378a975fbed

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(old, new):
    return {k:v for k,v in old.items() if k in new}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve({'a': 1, 'b': 2}, {'a': 3}), {'a': 3})", "check('fixture 2', solve({}, {'b': 2}), {'b': 2})", "check('fixture 3', solve({'a': 1}, {}), {})", "check('fixture 4', solve({}, {}), {})"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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
fixture 2{}{'b': 2}Failed
fixture 3{}{}Passed
fixture 4{}{}Passed
fixture 1{'a': 1}{'a': 3}Failed

SHA-256 / 7f6a7dbdc7b5bd7204f5dc699cc5cc15a0f840acac43ebf5d902c5812949aae9

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(old, new):
    return dict(new)
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve({'a': 1, 'b': 2}, {'a': 3}), {'a': 3})", "check('fixture 2', solve({}, {'b': 2}), {'b': 2})", "check('fixture 3', solve({'a': 1}, {}), {})", "check('fixture 4', solve({}, {}), {})"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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
fixture 2{'b': 2}{'b': 2}Passed
fixture 3{}{}Passed
fixture 4{}{}Passed
fixture 1{'a': 3}{'a': 3}Passed

SHA-256 / 59e77c024270bf930f0efec8f759583b7fb2c489776a0a8fe796bf0e30be4547

Verification & scope

Bounded deterministic policy model over validated inputs; not a complete protocol stack or an interoperability claim. The five variants rotate the same explicit fixture set. 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 2026-09-29T14:38:09.220900+00:00.

Case digest / 4f553bdceca2909a3196f22a6140490bb6eee153e0a3fd8d0e7b425f47ee4378