{"abstract":"The operation returns a result or retained state that violates this contract: Unary counter normalization retains strictly positive counts without changing them.","category":"Multiset accounting","checks":4,"contract":"Unary counter normalization retains strictly positive counts without changing them. Inputs are the finite Python values shown by the executable fixtures; no concurrent execution is assumed.","evaluation_group":"model-38a510272e9f1dcc","failed_approach":"An inclusive zero boundary retains zero entries.","family":"xr-counter-unary-plus-filters-strictly-positive","id":"FA-4686","implementations":{"attempt":{"sha256":"60d4b8f1221681eae4fde78861e3e3d2ddf0143e07f48c157d71581074744b8f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nfrom collections import Counter, ChainMap, deque\nimport heapq\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return {k:v for k,v in x.items() if v>=0}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('mixed signs', solve({'a': 2, 'b': 0, 'c': -1}), {'a': 2})\ncheck('zero', solve({'a': 0}), {})\ncheck('negative', solve({'a': -2}), {})\ncheck('empty', solve({}), {})\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":"7092f2abfaf112ae5c059b3eef316c97441e27a6b1eff5790c67a54ec39b8acf","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nfrom collections import Counter, ChainMap, deque\nimport heapq\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return dict(x)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('mixed signs', solve({'a': 2, 'b': 0, 'c': -1}), {'a': 2})\ncheck('zero', solve({'a': 0}), {})\ncheck('negative', solve({'a': -2}), {})\ncheck('empty', solve({}), {})\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":"7694401d1bcf209cbfa4d5362cfe1876ca7470f19a367e05c6c138e41a3b8587","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nfrom collections import Counter, ChainMap, deque\nimport heapq\nN = 1\nobservations = []\ndef solve(x, y=None):\n    return dict(+Counter(x))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('mixed signs', solve({'a': 2, 'b': 0, 'c': -1}), {'a': 2})\ncheck('zero', solve({'a': 0}), {})\ncheck('negative', solve({'a': -2}), {})\ncheck('empty', solve({}), {})\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-counter-unary-plus-filters-strictly-positive","generated_at":"2026-09-29T14:37:41.742655+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":"Unary counter normalization retains strictly positive counts without changing them.","root_cause":"Returning the raw mapping leaves zero and negative entries present.","sha256":"2745c5cc9f7c3a5beb40e8a6681f4e762063418271f2cf33b62832c406f4a01d","title":"Counter unary plus filters strictly positive · 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":35.288,"exit_code":1,"observations":[{"actual":{"a":2,"b":0},"check":"mixed signs","expected":{"a":2},"passed":false},{"actual":{"a":0},"check":"zero","expected":{},"passed":false},{"actual":{},"check":"negative","expected":{},"passed":true},{"actual":{},"check":"empty","expected":{},"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"mixed signs\", \"actual\": {\"a\": 2, \"b\": 0}, \"expected\": {\"a\": 2}, \"passed\": false}, {\"check\": \"zero\", \"actual\": {\"a\": 0}, \"expected\": {}, \"passed\": false}, {\"check\": \"negative\", \"actual\": {}, \"expected\": {}, \"passed\": true}, {\"check\": \"empty\", \"actual\": {}, \"expected\": {}, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":35.787,"exit_code":1,"observations":[{"actual":{"a":2,"b":0,"c":-1},"check":"mixed signs","expected":{"a":2},"passed":false},{"actual":{"a":0},"check":"zero","expected":{},"passed":false},{"actual":{"a":-2},"check":"negative","expected":{},"passed":false},{"actual":{},"check":"empty","expected":{},"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"mixed signs\", \"actual\": {\"a\": 2, \"b\": 0, \"c\": -1}, \"expected\": {\"a\": 2}, \"passed\": false}, {\"check\": \"zero\", \"actual\": {\"a\": 0}, \"expected\": {}, \"passed\": false}, {\"check\": \"negative\", \"actual\": {\"a\": -2}, \"expected\": {}, \"passed\": false}, {\"check\": \"empty\", \"actual\": {}, \"expected\": {}, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":38.85,"exit_code":0,"observations":[{"actual":{"a":2},"check":"mixed signs","expected":{"a":2},"passed":true},{"actual":{},"check":"zero","expected":{},"passed":true},{"actual":{},"check":"negative","expected":{},"passed":true},{"actual":{},"check":"empty","expected":{},"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"mixed signs\", \"actual\": {\"a\": 2}, \"expected\": {\"a\": 2}, \"passed\": true}, {\"check\": \"zero\", \"actual\": {}, \"expected\": {}, \"passed\": true}, {\"check\": \"negative\", \"actual\": {}, \"expected\": {}, \"passed\": true}, {\"check\": \"empty\", \"actual\": {}, \"expected\": {}, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}