{"abstract":"An assignment value loses embedded equals signs.","category":"Text processing","checks":4,"contract":"Split on the first equals sign, returning key and remainder; absent equals gives an empty remainder.","evaluation_group":"model-6b4228634bdcb2c7","failed_approach":"The attempted repair handles the primary example but still violates a separate boundary of the same contract.","family":"xp-partition-first","id":"FA-2986","implementations":{"attempt":{"sha256":"cc4264a53801183346d0bf332a7274f4cdf3e4d7ced3b85a8e172576edac182e","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.rsplit('=',1) if '=' in x else [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('a=b=c'), ['a', 'b=c'])\ncheck('boundary 2', solve('a'), ['a', ''])\ncheck('boundary 3', solve('=x'), ['', 'x'])\ncheck('boundary 4', solve('a='), ['a', ''])\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":"0a7b6ac9b410b8c2d06080e4a99a23081c7fecf35e236edcfcbdf4833de21c0f","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.split('=')[0],x.split('=')[-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('a=b=c'), ['a', 'b=c'])\ncheck('boundary 2', solve('a'), ['a', ''])\ncheck('boundary 3', solve('=x'), ['', 'x'])\ncheck('boundary 4', solve('a='), ['a', ''])\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":"b2a7a166474613b3b67f4e37b7962d98db1f4a865149a0f9f9f068bfa9999bfe","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.partition('=')[0],x.partition('=')[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('a=b=c'), ['a', 'b=c'])\ncheck('boundary 2', solve('a'), ['a', ''])\ncheck('boundary 3', solve('=x'), ['', 'x'])\ncheck('boundary 4', solve('a='), ['a', ''])\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-partition-first","generated_at":"2026-09-29T14:37:19.903161+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: Split on the first equals sign, returning key and remainder; absent equals gives an empty remainder.","root_cause":"The implementation applies an operation whose text or grammar semantics violate this contract: Split on the first equals sign, returning key and remainder; absent equals gives an empty remainder.","sha256":"e6740a69ccc8dc03042b81ca2cb43026c1f71dc3402708f993208cfd857d3496","title":"An assignment value loses embedded equals signs · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":60.665,"exit_code":1,"observations":[{"actual":["a=b","c"],"check":"boundary 1","expected":["a","b=c"],"passed":false},{"actual":["a",""],"check":"boundary 2","expected":["a",""],"passed":true},{"actual":["","x"],"check":"boundary 3","expected":["","x"],"passed":true},{"actual":["a",""],"check":"boundary 4","expected":["a",""],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": [\"a=b\", \"c\"], \"expected\": [\"a\", \"b=c\"], \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": [\"a\", \"\"], \"expected\": [\"a\", \"\"], \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": [\"\", \"x\"], \"expected\": [\"\", \"x\"], \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": [\"a\", \"\"], \"expected\": [\"a\", \"\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":58.633,"exit_code":1,"observations":[{"actual":["a","c"],"check":"boundary 1","expected":["a","b=c"],"passed":false},{"actual":["a","a"],"check":"boundary 2","expected":["a",""],"passed":false},{"actual":["","x"],"check":"boundary 3","expected":["","x"],"passed":true},{"actual":["a",""],"check":"boundary 4","expected":["a",""],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": [\"a\", \"c\"], \"expected\": [\"a\", \"b=c\"], \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": [\"a\", \"a\"], \"expected\": [\"a\", \"\"], \"passed\": false}, {\"check\": \"boundary 3\", \"actual\": [\"\", \"x\"], \"expected\": [\"\", \"x\"], \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": [\"a\", \"\"], \"expected\": [\"a\", \"\"], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":119.865,"exit_code":0,"observations":[{"actual":["a","b=c"],"check":"boundary 1","expected":["a","b=c"],"passed":true},{"actual":["a",""],"check":"boundary 2","expected":["a",""],"passed":true},{"actual":["","x"],"check":"boundary 3","expected":["","x"],"passed":true},{"actual":["a",""],"check":"boundary 4","expected":["a",""],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": [\"a\", \"b=c\"], \"expected\": [\"a\", \"b=c\"], \"passed\": true}, {\"check\": \"boundary 2\", \"actual\": [\"a\", \"\"], \"expected\": [\"a\", \"\"], \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": [\"\", \"x\"], \"expected\": [\"\", \"x\"], \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": [\"a\", \"\"], \"expected\": [\"a\", \"\"], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}