{"abstract":"Delimited empty fields vanish.","category":"Text processing","checks":4,"contract":"Split literal commas preserving all empty fields including the empty record.","contract_signature":"x","evaluation_group":"model-39261d4fc95cec4a","failed_approach":"The attempted repair handles the primary example but still violates a separate boundary of the same contract.","family":"xp-literal-empty-fields","id":"FA-3001","implementations":{"attempt":{"sha256":"44b3f1f34d982ff6561b20ca735b0b80cef8891a91f0bfdc69f7ae2da925ae75","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()\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,'), ['a', '', 'b', ''])\ncheck('boundary 2', solve(''), [''])\ncheck('boundary 3', solve(','), ['', ''])\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":"93284c3b079327da268b46d08ce2771dad7779162d2c104f01562c8048655675","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 [v for v in x.split(',') if v]\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,'), ['a', '', 'b', ''])\ncheck('boundary 2', solve(''), [''])\ncheck('boundary 3', solve(','), ['', ''])\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-literal-empty-fields","generated_at":"2026-09-29T14:37:19.905553+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.","root_cause":"The implementation applies an operation whose text or grammar semantics violate this contract: Split literal commas preserving all empty fields including the empty record.","sha256":"71914f09090bc7a8f2545478d82be428620282159a06e3234d7f1d225cf9f8a5","title":"Delimited empty fields vanish · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":46.855,"exit_code":1,"observations":[{"actual":["a,,b,"],"check":"boundary 1","expected":["a","","b",""],"passed":false},{"actual":[],"check":"boundary 2","expected":[""],"passed":false},{"actual":[","],"check":"boundary 3","expected":["",""],"passed":false},{"actual":["a"],"check":"boundary 4","expected":[" a "],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": [\"a,,b,\"], \"expected\": [\"a\", \"\", \"b\", \"\"], \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": [], \"expected\": [\"\"], \"passed\": false}, {\"check\": \"boundary 3\", \"actual\": [\",\"], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"boundary 4\", \"actual\": [\"a\"], \"expected\": [\" a \"], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":58.02,"exit_code":1,"observations":[{"actual":["a","b"],"check":"boundary 1","expected":["a","","b",""],"passed":false},{"actual":[],"check":"boundary 2","expected":[""],"passed":false},{"actual":[],"check":"boundary 3","expected":["",""],"passed":false},{"actual":[" a "],"check":"boundary 4","expected":[" a "],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"boundary 1\", \"actual\": [\"a\", \"b\"], \"expected\": [\"a\", \"\", \"b\", \"\"], \"passed\": false}, {\"check\": \"boundary 2\", \"actual\": [], \"expected\": [\"\"], \"passed\": false}, {\"check\": \"boundary 3\", \"actual\": [], \"expected\": [\"\", \"\"], \"passed\": false}, {\"check\": \"boundary 4\", \"actual\": [\" a \"], \"expected\": [\" a \"], \"passed\": true}], \"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."}}