{"abstract":"The operation returns a result or retained state that violates this contract: Return every occurrence of values that occur more than once.","category":"Sequence semantics","checks":4,"contract":"Return every occurrence of values that occur more than once. Inputs are the finite Python values shown by the executable fixtures; no concurrent execution is assumed.","evaluation_group":"model-d8d764ac3059b57f","failed_approach":"Deduplicating repeated values loses their required multiplicity.","family":"xr-all-duplicated-members","id":"FA-4106","implementations":{"attempt":{"sha256":"d6aca02f9cd60ab08a459bb31e2c5b0e242f12ba2908964deb79e52e29a64491","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return list(dict.fromkeys(v for v in x if x.count(v)>1))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('empty collection', solve([]), [])\ncheck('singleton collection', solve(['a']), [])\ncheck('two distinct elements', solve(['a', 'b']), [])\ncheck('nonadjacent duplicate and unsorted order', solve(['b', 'a', 'b', 'c']), ['b', 'b'])\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":"18d2624ae360778ee8a4a20ec194d0de9f2f3f6a9488c6f07492be20e8795f39","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return [v for i,v in enumerate(x) if v in x[:i]]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('empty collection', solve([]), [])\ncheck('singleton collection', solve(['a']), [])\ncheck('two distinct elements', solve(['a', 'b']), [])\ncheck('nonadjacent duplicate and unsorted order', solve(['b', 'a', 'b', 'c']), ['b', 'b'])\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":"2a58ae5a1a5561517e5aa71d36a148ca478f59f35aafb8228231d02e370eaa99","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return [v for v in x if x.count(v)>1]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('empty collection', solve([]), [])\ncheck('singleton collection', solve(['a']), [])\ncheck('two distinct elements', solve(['a', 'b']), [])\ncheck('nonadjacent duplicate and unsorted order', solve(['b', 'a', 'b', 'c']), ['b', 'b'])\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":"xr-all-duplicated-members","generated_at":"2026-09-29T14:37:35.702953+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A controlled local-runtime regression for collection APIs, language semantics, or ownership wrappers. Fixtures include boundary and interaction cases.","repair":"Return every occurrence of values that occur more than once.","root_cause":"A seen-set filter drops the first occurrence of each duplicated value.","sha256":"2b2998a1a50a6fb384ac8702957234a1b3e6a018b3453c37a869e867bd4baa62","title":"All duplicated members · case 01","variant":1,"variant_policy":"Five execution reruns of a fixed adversarial fixture suite; variant number does not alter semantic inputs.","verification":{"attempt":{"elapsed_ms":41.94,"exit_code":1,"observations":[{"actual":[],"check":"empty collection","expected":[],"passed":true},{"actual":[],"check":"singleton collection","expected":[],"passed":true},{"actual":[],"check":"two distinct elements","expected":[],"passed":true},{"actual":["b"],"check":"nonadjacent duplicate and unsorted order","expected":["b","b"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"singleton collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"two distinct elements\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"nonadjacent duplicate and unsorted order\", \"actual\": [\"b\"], \"expected\": [\"b\", \"b\"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.567,"exit_code":1,"observations":[{"actual":[],"check":"empty collection","expected":[],"passed":true},{"actual":[],"check":"singleton collection","expected":[],"passed":true},{"actual":[],"check":"two distinct elements","expected":[],"passed":true},{"actual":["b"],"check":"nonadjacent duplicate and unsorted order","expected":["b","b"],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"singleton collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"two distinct elements\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"nonadjacent duplicate and unsorted order\", \"actual\": [\"b\"], \"expected\": [\"b\", \"b\"], \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":97.474,"exit_code":0,"observations":[{"actual":[],"check":"empty collection","expected":[],"passed":true},{"actual":[],"check":"singleton collection","expected":[],"passed":true},{"actual":[],"check":"two distinct elements","expected":[],"passed":true},{"actual":["b","b"],"check":"nonadjacent duplicate and unsorted order","expected":["b","b"],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"singleton collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"two distinct elements\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"nonadjacent duplicate and unsorted order\", \"actual\": [\"b\", \"b\"], \"expected\": [\"b\", \"b\"], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}