{"abstract":"A cache namespace purge deletes similarly prefixed namespaces.","category":"Caching","checks":4,"contract":"Entries are [namespace,value]. Purge exact matching namespace identities only; namespaces are already separately parsed strings.","contract_signature":"entries, namespace","evaluation_group":"xc-namespace-invalidation","failed_approach":"Substring matching widens the accidental deletion set.","family":"xc-namespace-invalidation","id":"FA-10466","implementations":{"attempt":{"sha256":"58013aad57f03349acbacaaed8724ad32aa94644f668581868c84faff3ba8a5e","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(entries, namespace):\n    return [x for x in entries if namespace not in x[0]]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([['user', 1], ['users', 2], ['xuser', 3]], 'user')), [['users', 2], ['xuser', 3]])\ncheck('fixture 2', solve(*([['a', 1]], 'z')), [['a', 1]])\ncheck('fixture 3', solve(*([['', 1], ['x', 2]], '')), [['x', 2]])\ncheck('fixture 4', solve(*([], 'a')), [])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"19f0fac1c2f6a2fcc5c2c4de481c8f5fff048e1ddefc745f27671d5b02e37c90","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(entries, namespace):\n    return [x for x in entries if not x[0].startswith(namespace)]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1', solve(*([['user', 1], ['users', 2], ['xuser', 3]], 'user')), [['users', 2], ['xuser', 3]])\ncheck('fixture 2', solve(*([['a', 1]], 'z')), [['a', 1]])\ncheck('fixture 3', solve(*([['', 1], ['x', 2]], '')), [['x', 2]])\ncheck('fixture 4', solve(*([], 'a')), [])\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":" 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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xc-namespace-invalidation","generated_at":"2026-09-29T14:38:39.270279+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic cache state transformation. Inputs are copied or treated as immutable; no remote storage, real clock, or concurrent interleaving is simulated.","root_cause":"A textual prefix is used where namespace identity is an exact field.","sha256":"7e477e12295fc4417b0cebb9ab3faa2b1fd78a6f5655b9f056e5d18f78413fbe","title":"A cache namespace purge deletes similarly prefixed namespaces · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":42.185,"exit_code":1,"observations":[{"actual":[],"check":"fixture 1","expected":[["users",2],["xuser",3]],"passed":false},{"actual":[["a",1]],"check":"fixture 2","expected":[["a",1]],"passed":true},{"actual":[],"check":"fixture 3","expected":[["x",2]],"passed":false},{"actual":[],"check":"fixture 4","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [], \"expected\": [[\"users\", 2], [\"xuser\", 3]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [[\"a\", 1]], \"expected\": [[\"a\", 1]], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [[\"x\", 2]], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":44.979,"exit_code":1,"observations":[{"actual":[["xuser",3]],"check":"fixture 1","expected":[["users",2],["xuser",3]],"passed":false},{"actual":[["a",1]],"check":"fixture 2","expected":[["a",1]],"passed":true},{"actual":[],"check":"fixture 3","expected":[["x",2]],"passed":false},{"actual":[],"check":"fixture 4","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1\", \"actual\": [[\"xuser\", 3]], \"expected\": [[\"users\", 2], [\"xuser\", 3]], \"passed\": false}, {\"check\": \"fixture 2\", \"actual\": [[\"a\", 1]], \"expected\": [[\"a\", 1]], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [], \"expected\": [[\"x\", 2]], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}