{"abstract":"Connection close notification is emitted once.","category":"Connection lifecycle","checks":4,"contract":"Given was_closed, now_closed, leased, connection close notification is emitted once. Return the protocol decision or transformed value; fields are validated and fixtures state boundary outcomes.","contract_signature":"was_closed, now_closed, leased","evaluation_group":"xh-connection-close-notification-is-emitted-once","failed_approach":"The attempted repair uses `[\"notify\"] if now_closed and not was_closed else []` and still violates a separate fixture.","family":"xh-connection-close-notification-is-emitted-once","id":"FA-7786","implementations":{"attempt":{"sha256":"e31b036622854ccdbaa5104a704b4b0ec442dbd08a939c1d928cb7f04b932786","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(was_closed, now_closed, leased):\n    return [\"notify\"] if now_closed and not was_closed else []\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve(False, True, True), ['notify', 'release'])\", \"check('fixture 2', solve(True, True, True), [])\", \"check('fixture 3', solve(False, True, False), ['notify'])\", \"check('fixture 4', solve(True, False, False), [])\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\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":"b31d77d697a09b6d74a84392a5c11b6802688a6c455b52d3526c58e85270b696","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport ipaddress\nimport re\nfrom urllib.parse import urlsplit, urljoin\nN = 1\nobservations = []\ndef solve(was_closed, now_closed, leased):\n    return [\"notify\",\"release\"] if now_closed else []\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve(False, True, True), ['notify', 'release'])\", \"check('fixture 2', solve(True, True, True), [])\", \"check('fixture 3', solve(False, True, False), ['notify'])\", \"check('fixture 4', solve(True, False, False), [])\"]\nfor _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:\n    exec(_line)\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":"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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xh-connection-close-notification-is-emitted-once","generated_at":"2026-09-29T14:38:15.306791+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic connection lifecycle model isolates the connection-close-notification-is-emitted-once policy at a network component boundary.","root_cause":"The faulty implementation uses `[\"notify\",\"release\"] if now_closed else []` for the connection-close-notification-is-emitted-once decision.","sha256":"79265a1391da7c8c19122f282c91a1c93f9a3fb3dee8b323476422e567e86799","title":"Connection close notification is emitted once · 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":41.662,"exit_code":1,"observations":[{"actual":[],"check":"fixture 2","expected":[],"passed":true},{"actual":["notify"],"check":"fixture 3","expected":["notify"],"passed":true},{"actual":[],"check":"fixture 4","expected":[],"passed":true},{"actual":["notify"],"check":"fixture 1","expected":["notify","release"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": [\"notify\"], \"expected\": [\"notify\"], \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": [\"notify\"], \"expected\": [\"notify\", \"release\"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":42.76,"exit_code":1,"observations":[{"actual":["notify","release"],"check":"fixture 2","expected":[],"passed":false},{"actual":["notify","release"],"check":"fixture 3","expected":["notify"],"passed":false},{"actual":[],"check":"fixture 4","expected":[],"passed":true},{"actual":["notify","release"],"check":"fixture 1","expected":["notify","release"],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": [\"notify\", \"release\"], \"expected\": [], \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": [\"notify\", \"release\"], \"expected\": [\"notify\"], \"passed\": false}, {\"check\": \"fixture 4\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": [\"notify\", \"release\"], \"expected\": [\"notify\", \"release\"], \"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."}}