{"abstract":"Character count underestimates an encoded field.","category":"Encodings","checks":4,"contract":"Return the strict UTF-8 byte length of scalar-value text.","evaluation_group":"encoding-utf8-byte-length","failed_approach":"The attempted repair handles the primary example but still violates a separate boundary of the same contract.","family":"xp-utf8-byte-length","id":"FA-2936","implementations":{"attempt":{"sha256":"ae66154c6cdcade4996224a4bc51e9377c1b8d800c7596bff8847bae83143078","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 len(x.encode('utf-16-le'))\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('é'), 2)\ncheck('boundary 2', solve('😀'), 4)\ncheck('boundary 3', solve('abc'), 3)\ncheck('boundary 4', solve(''), 0)\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":"26761bda6e104bd95acf9a2b881e6a28d10e6922d16353bbf27ee19f3ec16c9c","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 len(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('é'), 2)\ncheck('boundary 2', solve('😀'), 4)\ncheck('boundary 3', solve('abc'), 3)\ncheck('boundary 4', solve(''), 0)\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":"077b9a88431ede412b6c7fd500f6b0a37b74d92d1fdf1bef03c16bbfbc790202","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 len(x.encode('utf-8'))\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('é'), 2)\ncheck('boundary 2', solve('😀'), 4)\ncheck('boundary 3', solve('abc'), 3)\ncheck('boundary 4', solve(''), 0)\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-utf8-byte-length","generated_at":"2026-09-29T14:37:19.051382+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: Return the strict UTF-8 byte length of scalar-value text.","root_cause":"The implementation applies an operation whose text or grammar semantics violate this contract: Return the strict UTF-8 byte length of scalar-value text.","sha256":"ffce5e469ca08d53e3eaf6344018a1a1eebdd5e3ec24ad1d03419b89b29ee4f1","title":"Character count underestimates an encoded field · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":55.739,"exit_code":1,"observations":[{"actual":2,"check":"boundary 1","expected":2,"passed":true},{"actual":4,"check":"boundary 2","expected":4,"passed":true},{"actual":6,"check":"boundary 3","expected":3,"passed":false},{"actual":0,"check":"boundary 4","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"boundary 2\", \"actual\": 4, \"expected\": 4, \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": 6, \"expected\": 3, \"passed\": false}, {\"check\": \"boundary 4\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":52.674,"exit_code":1,"observations":[{"actual":1,"check":"boundary 1","expected":2,"passed":false},{"actual":1,"check":"boundary 2","expected":4,"passed":false},{"actual":3,"check":"boundary 3","expected":3,"passed":true},{"actual":0,"check":"boundary 4","expected":0,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": 1, \"expected\": 2, \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": 1, \"expected\": 4, \"passed\": false}, {\"check\": \"boundary 3\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":136.43,"exit_code":0,"observations":[{"actual":2,"check":"boundary 1","expected":2,"passed":true},{"actual":4,"check":"boundary 2","expected":4,"passed":true},{"actual":3,"check":"boundary 3","expected":3,"passed":true},{"actual":0,"check":"boundary 4","expected":0,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"boundary 2\", \"actual\": 4, \"expected\": 4, \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": 0, \"expected\": 0, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}