{"abstract":"Would block preserves entire unsent write buffer.","category":"Connection lifecycle","checks":4,"contract":"Bounded offline decision model: would block preserves entire unsent write buffer. Inputs are already validated protocol fields; the explicit fixtures define the supported policy, not a complete protocol implementation.","evaluation_group":"xh-would-block-preserves-entire-unsent-write-buffer","failed_approach":"The attempted repair uses `data` and still violates a separate fixture.","family":"xh-would-block-preserves-entire-unsent-write-buffer","id":"FA-7796","implementations":{"attempt":{"sha256":"54427be2b7bf52d99ddd5fa3f76a05f0318c74b849049f862caae20063bc34f4","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(data, would_block, written):\n    return data\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve('abc', True, 2), 'abc')\", \"check('fixture 2', solve('abc', False, 2), 'c')\", \"check('fixture 3', solve('', True, 0), '')\", \"check('fixture 4', solve('abc', False, 0), 'abc')\"]\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":"f8720290d287933bfce12c561445d8145ee3a48ca83ad63e7fbe6bd122423f14","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(data, would_block, written):\n    return data[written:]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve('abc', True, 2), 'abc')\", \"check('fixture 2', solve('abc', False, 2), 'c')\", \"check('fixture 3', solve('', True, 0), '')\", \"check('fixture 4', solve('abc', False, 0), 'abc')\"]\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"},"fixed":{"sha256":"b043a3f9866cb7a5b9dd3baee781e8cfe34700b83cbc38747e399e92951cbcff","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(data, would_block, written):\n    return data if would_block else data[written:]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\n_fixtures = [\"check('fixture 1', solve('abc', True, 2), 'abc')\", \"check('fixture 2', solve('abc', False, 2), 'c')\", \"check('fixture 3', solve('', True, 0), '')\", \"check('fixture 4', solve('abc', False, 0), 'abc')\"]\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-would-block-preserves-entire-unsent-write-buffer","generated_at":"2026-09-29T14:38:15.444913+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic connection lifecycle model isolates the would-block-preserves-entire-unsent-write-buffer policy at a network component boundary.","repair":"Apply the explicit would-block-preserves-entire-unsent-write-buffer contract, including the tested boundary and negative cases.","root_cause":"The faulty implementation uses `data[written:]` for the would-block-preserves-entire-unsent-write-buffer decision.","sha256":"456a4f2f2254f1c586e837f00e34499151896682a592d28add56cbbc740dbfb9","title":"Would block preserves entire unsent write buffer · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":40.544,"exit_code":1,"observations":[{"actual":"abc","check":"fixture 2","expected":"c","passed":false},{"actual":"","check":"fixture 3","expected":"","passed":true},{"actual":"abc","check":"fixture 4","expected":"abc","passed":true},{"actual":"abc","check":"fixture 1","expected":"abc","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": \"abc\", \"expected\": \"c\", \"passed\": false}, {\"check\": \"fixture 3\", \"actual\": \"\", \"expected\": \"\", \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": \"abc\", \"expected\": \"abc\", \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": \"abc\", \"expected\": \"abc\", \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.168,"exit_code":1,"observations":[{"actual":"c","check":"fixture 2","expected":"c","passed":true},{"actual":"","check":"fixture 3","expected":"","passed":true},{"actual":"abc","check":"fixture 4","expected":"abc","passed":true},{"actual":"c","check":"fixture 1","expected":"abc","passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": \"c\", \"expected\": \"c\", \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": \"\", \"expected\": \"\", \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": \"abc\", \"expected\": \"abc\", \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": \"c\", \"expected\": \"abc\", \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":43.696,"exit_code":0,"observations":[{"actual":"c","check":"fixture 2","expected":"c","passed":true},{"actual":"","check":"fixture 3","expected":"","passed":true},{"actual":"abc","check":"fixture 4","expected":"abc","passed":true},{"actual":"abc","check":"fixture 1","expected":"abc","passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 2\", \"actual\": \"c\", \"expected\": \"c\", \"passed\": true}, {\"check\": \"fixture 3\", \"actual\": \"\", \"expected\": \"\", \"passed\": true}, {\"check\": \"fixture 4\", \"actual\": \"abc\", \"expected\": \"abc\", \"passed\": true}, {\"check\": \"fixture 1\", \"actual\": \"abc\", \"expected\": \"abc\", \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}