{"abstract":"Batched store updates notify consumers before all writes become observable.","category":"Client state","checks":6,"contract":"A client-store commit applies the entire write batch then emits exactly one selector projection; empty batches emit nothing and selectors observe the final value of repeated writes.","contract_signature":"initial, writes, observed_keys","evaluation_group":"s3-client-state-store-commit-batch-notify","failed_approach":"The partial repair still violates at least one explicit regression oracle.","family":"s3-client-state-store-commit-batch-notify","id":"FA-24811","implementations":{"attempt":{"sha256":"02f9d5fdacd856608fab3b4dd2adda5ac09ad1f29ff09e28b1c0f71352f1fb9c","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(initial, writes, observed_keys):\n    state=dict(initial)\n    for key,value in writes: state[key]=value\n    return [[state.get(key) for key in observed_keys]]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('atomic multi-key change', solve({'a':1,'b':2},[('a',N),('b',N+1)],['a','b']), [[N,N+1]])\ncheck('no writes no notify', solve({'a':1},[],['a']), [])\ncheck('last write wins', solve({},[('a',1),('a',2)],['a']), [[2]])\ncheck('missing observed field', solve({},[('a',1)],['b']), [[None]])\ncheck('empty observer projection', solve({},[('a',1)],[]), [[]])\ncheck('false value delivered', solve({},[('a',False)],['a']), [[False]])\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":"dd25efccef2c1b198cf8c88623f244a377eeddb0c7eec5ea971aa9bb3b858ebc","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(initial, writes, observed_keys):\n    state=dict(initial); notices=[]\n    for key,value in writes:\n        state[key]=value; notices.append([state.get(key) for key in observed_keys])\n    return notices\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('atomic multi-key change', solve({'a':1,'b':2},[('a',N),('b',N+1)],['a','b']), [[N,N+1]])\ncheck('no writes no notify', solve({'a':1},[],['a']), [])\ncheck('last write wins', solve({},[('a',1),('a',2)],['a']), [[2]])\ncheck('missing observed field', solve({},[('a',1)],['b']), [[None]])\ncheck('empty observer projection', solve({},[('a',1)],[]), [[]])\ncheck('false value delivered', solve({},[('a',False)],['a']), [[False]])\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 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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"s3-client-state-store-commit-batch-notify","generated_at":"2026-09-29T14:41:00.994430+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A bounded offline client-state transition with explicit lifecycle inputs.","root_cause":"The faulty implementation violates A client-store commit applies the entire write batch then emits exactly one selector projection; empty batches emit nothing and selectors observe the final value of repeated writes.","sha256":"492ac807402b2096a14fda793968da07f7f0fa9f0882bb1901f6fdf8f78481b5","title":"Batched store updates notify consumers before all writes become observable · 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":40.668,"exit_code":1,"observations":[{"actual":[[1,2]],"check":"atomic multi-key change","expected":[[1,2]],"passed":true},{"actual":[[1]],"check":"no writes no notify","expected":[],"passed":false},{"actual":[[2]],"check":"last write wins","expected":[[2]],"passed":true},{"actual":[[null]],"check":"missing observed field","expected":[[null]],"passed":true},{"actual":[[]],"check":"empty observer projection","expected":[[]],"passed":true},{"actual":[[false]],"check":"false value delivered","expected":[[false]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"atomic multi-key change\", \"actual\": [[1, 2]], \"expected\": [[1, 2]], \"passed\": true}, {\"check\": \"no writes no notify\", \"actual\": [[1]], \"expected\": [], \"passed\": false}, {\"check\": \"last write wins\", \"actual\": [[2]], \"expected\": [[2]], \"passed\": true}, {\"check\": \"missing observed field\", \"actual\": [[null]], \"expected\": [[null]], \"passed\": true}, {\"check\": \"empty observer projection\", \"actual\": [[]], \"expected\": [[]], \"passed\": true}, {\"check\": \"false value delivered\", \"actual\": [[false]], \"expected\": [[false]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.863,"exit_code":1,"observations":[{"actual":[[1,2],[1,2]],"check":"atomic multi-key change","expected":[[1,2]],"passed":false},{"actual":[],"check":"no writes no notify","expected":[],"passed":true},{"actual":[[1],[2]],"check":"last write wins","expected":[[2]],"passed":false},{"actual":[[null]],"check":"missing observed field","expected":[[null]],"passed":true},{"actual":[[]],"check":"empty observer projection","expected":[[]],"passed":true},{"actual":[[false]],"check":"false value delivered","expected":[[false]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"atomic multi-key change\", \"actual\": [[1, 2], [1, 2]], \"expected\": [[1, 2]], \"passed\": false}, {\"check\": \"no writes no notify\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"last write wins\", \"actual\": [[1], [2]], \"expected\": [[2]], \"passed\": false}, {\"check\": \"missing observed field\", \"actual\": [[null]], \"expected\": [[null]], \"passed\": true}, {\"check\": \"empty observer projection\", \"actual\": [[]], \"expected\": [[]], \"passed\": true}, {\"check\": \"false value delivered\", \"actual\": [[false]], \"expected\": [[false]], \"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."}}