{"abstract":"No-store metadata prevents partial staging from surviving admission.","category":"HTTP ranges","checks":6,"contract":"Return [staged,committed] unchanged for reusable responses; no-store clears both temporary and committed bytes for this object.","contract_signature":"no_store, staged, committed","evaluation_group":"s3-http_ranges-cache-assembly","failed_approach":"The partial repair uses return [staged,\"\"] if no_store else [staged,committed], which still violates the stated contract.","family":"s3-http_ranges-cache-no-store-purges-staging","id":"FA-26536","implementations":{"attempt":{"sha256":"1de97b5b466908444cc56142ad9b3ee9d0c0b4d7a43b5ffe31582a137079d9dd","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(no_store, staged, committed):\n    return [staged,\"\"] if no_store else [staged,committed]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('cache-no-store-purges-staging fixture 0', solve(True,\"s\"*N,\"c\"*N), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 1', solve(True,\"s\",\"\"), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 2', solve(True,\"\",\"c\"), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 3', solve(False,\"s\"*N,\"c\"), [\"s\"*N,\"c\"])\ncheck('cache-no-store-purges-staging fixture 4', solve(False,\"\",\"\"), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 5', solve(False,\"s\",\"\"), [\"s\",\"\"])\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":"67d9c12f3d59e0d6bd8e411ade6b5ebf587de48f758a4c22e2d7d83d10bd06eb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(no_store, staged, committed):\n    return [staged,committed]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('cache-no-store-purges-staging fixture 0', solve(True,\"s\"*N,\"c\"*N), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 1', solve(True,\"s\",\"\"), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 2', solve(True,\"\",\"c\"), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 3', solve(False,\"s\"*N,\"c\"), [\"s\"*N,\"c\"])\ncheck('cache-no-store-purges-staging fixture 4', solve(False,\"\",\"\"), [\"\",\"\"])\ncheck('cache-no-store-purges-staging fixture 5', solve(False,\"s\",\"\"), [\"s\",\"\"])\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":"Deterministic simplified range service, with stipulated local policies and already parsed trusted inputs; not a complete HTTP implementation. 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-http_ranges-cache-no-store-purges-staging","generated_at":"2026-09-29T14:41:16.906420+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Range responses combine representation identity, conditional requests, framing, and partial-object state.","root_cause":"The cache-no-store-purges-staging decision uses return [staged,committed].","sha256":"80e76b0a64a654a59403a1fda45ddc7b25015ede89b1de5687a03ff1979460ec","title":"No-store metadata prevents partial staging from surviving admission · 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":40.772,"exit_code":1,"observations":[{"actual":["s",""],"check":"cache-no-store-purges-staging fixture 0","expected":["",""],"passed":false},{"actual":["s",""],"check":"cache-no-store-purges-staging fixture 1","expected":["",""],"passed":false},{"actual":["",""],"check":"cache-no-store-purges-staging fixture 2","expected":["",""],"passed":true},{"actual":["s","c"],"check":"cache-no-store-purges-staging fixture 3","expected":["s","c"],"passed":true},{"actual":["",""],"check":"cache-no-store-purges-staging fixture 4","expected":["",""],"passed":true},{"actual":["s",""],"check":"cache-no-store-purges-staging fixture 5","expected":["s",""],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"cache-no-store-purges-staging fixture 0\", \"actual\": [\"s\", \"\"], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"cache-no-store-purges-staging fixture 1\", \"actual\": [\"s\", \"\"], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"cache-no-store-purges-staging fixture 2\", \"actual\": [\"\", \"\"], \"expected\": [\"\", \"\"], \"passed\": true}, {\"check\": \"cache-no-store-purges-staging fixture 3\", \"actual\": [\"s\", \"c\"], \"expected\": [\"s\", \"c\"], \"passed\": true}, {\"check\": \"cache-no-store-purges-staging fixture 4\", \"actual\": [\"\", \"\"], \"expected\": [\"\", \"\"], \"passed\": true}, {\"check\": \"cache-no-store-purges-staging fixture 5\", \"actual\": [\"s\", \"\"], \"expected\": [\"s\", \"\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":40.96,"exit_code":1,"observations":[{"actual":["s","c"],"check":"cache-no-store-purges-staging fixture 0","expected":["",""],"passed":false},{"actual":["s",""],"check":"cache-no-store-purges-staging fixture 1","expected":["",""],"passed":false},{"actual":["","c"],"check":"cache-no-store-purges-staging fixture 2","expected":["",""],"passed":false},{"actual":["s","c"],"check":"cache-no-store-purges-staging fixture 3","expected":["s","c"],"passed":true},{"actual":["",""],"check":"cache-no-store-purges-staging fixture 4","expected":["",""],"passed":true},{"actual":["s",""],"check":"cache-no-store-purges-staging fixture 5","expected":["s",""],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"cache-no-store-purges-staging fixture 0\", \"actual\": [\"s\", \"c\"], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"cache-no-store-purges-staging fixture 1\", \"actual\": [\"s\", \"\"], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"cache-no-store-purges-staging fixture 2\", \"actual\": [\"\", \"c\"], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"cache-no-store-purges-staging fixture 3\", \"actual\": [\"s\", \"c\"], \"expected\": [\"s\", \"c\"], \"passed\": true}, {\"check\": \"cache-no-store-purges-staging fixture 4\", \"actual\": [\"\", \"\"], \"expected\": [\"\", \"\"], \"passed\": true}, {\"check\": \"cache-no-store-purges-staging fixture 5\", \"actual\": [\"s\", \"\"], \"expected\": [\"s\", \"\"], \"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."}}