{"abstract":"A bounded replacement modifies every occurrence.","category":"Text processing","checks":4,"contract":"Replace at most the first two literal aa occurrences with X, nonoverlapping.","evaluation_group":"model-6ee9dcb9d73ce435","failed_approach":"The attempted repair handles the primary example but still violates a separate boundary of the same contract.","family":"xp-replace-count","id":"FA-3031","implementations":{"attempt":{"sha256":"e3eca6d5a8764b261fa0273b6a69ad1c8651bf0cf9e4d30ae79548a6abc7f98f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct\nfrom urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit\nfrom email.header import decode_header, make_header\nfrom email.utils import getaddresses\nfrom xml.etree import ElementTree as ET\nimport shlex, string, textwrap\n\nN = 1\nobservations = []\ndef solve(x):\n    try:\n        return x.replace('aa','X',1)\n    except Exception as exc:\n        return {\"error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('boundary 1', solve('aaaaaa'), 'XXaa')\ncheck('boundary 2', solve('aaaa'), 'XX')\ncheck('boundary 3', solve('aaa'), 'Xa')\ncheck('boundary 4', solve('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":"797f9077dc75c34d90d28e35884284c3568db07beb3d6e0fb2a10f1f492e174d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct\nfrom urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit\nfrom email.header import decode_header, make_header\nfrom email.utils import getaddresses\nfrom xml.etree import ElementTree as ET\nimport shlex, string, textwrap\n\nN = 1\nobservations = []\ndef solve(x):\n    try:\n        return x.replace('aa','X')\n    except Exception as exc:\n        return {\"error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('boundary 1', solve('aaaaaa'), 'XXaa')\ncheck('boundary 2', solve('aaaa'), 'XX')\ncheck('boundary 3', solve('aaa'), 'Xa')\ncheck('boundary 4', solve('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":"3b89cba71093c2ac6db8d1ab0bffc5fa9775dd0f9478b8d58c99fad8e5ba5996","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct\nfrom urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit\nfrom email.header import decode_header, make_header\nfrom email.utils import getaddresses\nfrom xml.etree import ElementTree as ET\nimport shlex, string, textwrap\n\nN = 1\nobservations = []\ndef solve(x):\n    try:\n        return x.replace('aa','X',2)\n    except Exception as exc:\n        return {\"error\": type(exc).__name__}\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('boundary 1', solve('aaaaaa'), 'XXaa')\ncheck('boundary 2', solve('aaaa'), 'XX')\ncheck('boundary 3', solve('aaa'), 'Xa')\ncheck('boundary 4', solve('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":"xp-replace-count","generated_at":"2026-09-29T14:37:20.514253+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A local executable model for consumers of structured text; oracle values are authored literals, not outputs copied from the repaired implementation.","repair":"Implement the complete stated contract, including the boundary fixtures: Replace at most the first two literal aa occurrences with X, nonoverlapping.","root_cause":"The implementation applies an operation whose text or grammar semantics violate this contract: Replace at most the first two literal aa occurrences with X, nonoverlapping.","sha256":"8888e1e7ebdac986bd4ce5546bc6bd1e78e15b0fffa87997005cbd2917daf20c","title":"A bounded replacement modifies every occurrence · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":53.384,"exit_code":1,"observations":[{"actual":"Xaaaa","check":"boundary 1","expected":"XXaa","passed":false},{"actual":"Xaa","check":"boundary 2","expected":"XX","passed":false},{"actual":"Xa","check":"boundary 3","expected":"Xa","passed":true},{"actual":"b","check":"boundary 4","expected":"b","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": \"Xaaaa\", \"expected\": \"XXaa\", \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": \"Xaa\", \"expected\": \"XX\", \"passed\": false}, {\"check\": \"boundary 3\", \"actual\": \"Xa\", \"expected\": \"Xa\", \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": \"b\", \"expected\": \"b\", \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":53.574,"exit_code":1,"observations":[{"actual":"XXX","check":"boundary 1","expected":"XXaa","passed":false},{"actual":"XX","check":"boundary 2","expected":"XX","passed":true},{"actual":"Xa","check":"boundary 3","expected":"Xa","passed":true},{"actual":"b","check":"boundary 4","expected":"b","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": \"XXX\", \"expected\": \"XXaa\", \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": \"XX\", \"expected\": \"XX\", \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": \"Xa\", \"expected\": \"Xa\", \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": \"b\", \"expected\": \"b\", \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":54.678,"exit_code":0,"observations":[{"actual":"XXaa","check":"boundary 1","expected":"XXaa","passed":true},{"actual":"XX","check":"boundary 2","expected":"XX","passed":true},{"actual":"Xa","check":"boundary 3","expected":"Xa","passed":true},{"actual":"b","check":"boundary 4","expected":"b","passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": \"XXaa\", \"expected\": \"XXaa\", \"passed\": true}, {\"check\": \"boundary 2\", \"actual\": \"XX\", \"expected\": \"XX\", \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": \"Xa\", \"expected\": \"Xa\", \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": \"b\", \"expected\": \"b\", \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}