{"abstract":"The operation returns a result or retained state that violates this contract: Return all nonempty suffixes in increasing start-position order.","category":"Sequence semantics","checks":4,"contract":"Return all nonempty suffixes in increasing start-position order. Inputs are the finite Python values shown by the executable fixtures; no concurrent execution is assumed.","contract_signature":"x, y=None","evaluation_group":"model-a8e597e661804dc7","failed_approach":"Prefix slicing uses the wrong side of each boundary.","family":"xr-all-nonempty-suffixes","id":"FA-4186","implementations":{"attempt":{"sha256":"9c8fea5ed22e7c11f81e4db3e716455187b14664b38aa6e9aec4f1fb69517a31","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return [x[:i] for i in range(len(x))]\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']), [['a']])\ncheck('two distinct elements', solve(['a', 'b']), [['a', 'b'], ['b']])\ncheck('nonadjacent duplicate and unsorted order', solve(['b', 'a', 'b', 'c']), [['b', 'a', 'b', 'c'], ['a', 'b', 'c'], ['b', 'c'], ['c']])\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":"e0b81c5c73c149c7b6df6098cf7afd874c4f4b1c9f4b70f2837a80cff002dd99","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return [x[i:] for i in range(1,len(x)+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']), [['a']])\ncheck('two distinct elements', solve(['a', 'b']), [['a', 'b'], ['b']])\ncheck('nonadjacent duplicate and unsorted order', solve(['b', 'a', 'b', 'c']), [['b', 'a', 'b', 'c'], ['a', 'b', 'c'], ['b', 'c'], ['c']])\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-nonempty-suffixes","generated_at":"2026-09-29T14:37:36.503518+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.","root_cause":"The suffix range skips the full sequence and includes the empty suffix.","sha256":"45e2357cc47e65bf4bf151c20d769480666b0f20cf1f545965061f1b07c502e5","title":"All nonempty suffixes · case 01","variant":1,"variant_policy":"Five execution reruns of a fixed adversarial fixture suite; variant number does not alter semantic inputs.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":37.591,"exit_code":1,"observations":[{"actual":[],"check":"empty collection","expected":[],"passed":true},{"actual":[[]],"check":"singleton collection","expected":[["a"]],"passed":false},{"actual":[[],["a"]],"check":"two distinct elements","expected":[["a","b"],["b"]],"passed":false},{"actual":[[],["b"],["b","a"],["b","a","b"]],"check":"nonadjacent duplicate and unsorted order","expected":[["b","a","b","c"],["a","b","c"],["b","c"],["c"]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"singleton collection\", \"actual\": [[]], \"expected\": [[\"a\"]], \"passed\": false}, {\"check\": \"two distinct elements\", \"actual\": [[], [\"a\"]], \"expected\": [[\"a\", \"b\"], [\"b\"]], \"passed\": false}, {\"check\": \"nonadjacent duplicate and unsorted order\", \"actual\": [[], [\"b\"], [\"b\", \"a\"], [\"b\", \"a\", \"b\"]], \"expected\": [[\"b\", \"a\", \"b\", \"c\"], [\"a\", \"b\", \"c\"], [\"b\", \"c\"], [\"c\"]], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":112.844,"exit_code":1,"observations":[{"actual":[],"check":"empty collection","expected":[],"passed":true},{"actual":[[]],"check":"singleton collection","expected":[["a"]],"passed":false},{"actual":[["b"],[]],"check":"two distinct elements","expected":[["a","b"],["b"]],"passed":false},{"actual":[["a","b","c"],["b","c"],["c"],[]],"check":"nonadjacent duplicate and unsorted order","expected":[["b","a","b","c"],["a","b","c"],["b","c"],["c"]],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"empty collection\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"singleton collection\", \"actual\": [[]], \"expected\": [[\"a\"]], \"passed\": false}, {\"check\": \"two distinct elements\", \"actual\": [[\"b\"], []], \"expected\": [[\"a\", \"b\"], [\"b\"]], \"passed\": false}, {\"check\": \"nonadjacent duplicate and unsorted order\", \"actual\": [[\"a\", \"b\", \"c\"], [\"b\", \"c\"], [\"c\"], []], \"expected\": [[\"b\", \"a\", \"b\", \"c\"], [\"a\", \"b\", \"c\"], [\"b\", \"c\"], [\"c\"]], \"passed\": false}], \"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."}}