{"abstract":"A backslash-escaped delimiter is treated as a field boundary.","category":"Delimited text","checks":4,"contract":"Parse one comma-delimited row with backslash escaping and no quote semantics.","evaluation_group":"model-5e2a9ac0e536c876","failed_approach":"The attempted repair handles the primary example but still violates a separate boundary of the same contract.","family":"xp-csv-escapechar-dialect","id":"FA-4021","implementations":{"attempt":{"sha256":"0b7db9821deb1239412411bb23855610950d4b869ff71be07858260197887191","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 next(csv.reader([x],escapechar=\"\\\\\"))\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,b\"'), ['\"a', 'b\"'])\ncheck('boundary 3', solve('a\\\\\\\\b'), ['a\\\\b'])\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":"2872b407b33cb872a987cdab7cf00f6a446f23bb2e648f94a30d35fcfa4bbe0e","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,c'), ['a,b', 'c'])\ncheck('boundary 2', solve('\"a,b\"'), ['\"a', 'b\"'])\ncheck('boundary 3', solve('a\\\\\\\\b'), ['a\\\\b'])\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":"e53816ed8f38ebd763cca6805ef46b99a0292fd98e8342652df8a39e6eeec749","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 next(csv.reader([x],escapechar=\"\\\\\",quoting=csv.QUOTE_NONE))\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,b\"'), ['\"a', 'b\"'])\ncheck('boundary 3', solve('a\\\\\\\\b'), ['a\\\\b'])\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-csv-escapechar-dialect","generated_at":"2026-09-29T14:37:34.556047+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: Parse one comma-delimited row with backslash escaping and no quote semantics.","root_cause":"The implementation applies an operation whose text or grammar semantics violate this contract: Parse one comma-delimited row with backslash escaping and no quote semantics.","sha256":"36c03ebe042e5fedaa5086469b14aa912a967fbf4c235ac1867002d60d1a222a","title":"A backslash-escaped delimiter is treated as a field boundary · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":58.783,"exit_code":1,"observations":[{"actual":["a,b","c"],"check":"boundary 1","expected":["a,b","c"],"passed":true},{"actual":["a,b"],"check":"boundary 2","expected":["\"a","b\""],"passed":false},{"actual":["a\\b"],"check":"boundary 3","expected":["a\\b"],"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\": true}, {\"check\": \"boundary 2\", \"actual\": [\"a,b\"], \"expected\": [\"\\\"a\", \"b\\\"\"], \"passed\": false}, {\"check\": \"boundary 3\", \"actual\": [\"a\\\\b\"], \"expected\": [\"a\\\\b\"], \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": [\"a\", \"\", \"\"], \"expected\": [\"a\", \"\", \"\"], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":57.681,"exit_code":1,"observations":[{"actual":["a\\","b","c"],"check":"boundary 1","expected":["a,b","c"],"passed":false},{"actual":["\"a","b\""],"check":"boundary 2","expected":["\"a","b\""],"passed":true},{"actual":["a\\\\b"],"check":"boundary 3","expected":["a\\b"],"passed":false},{"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\", \"b\\\"\"], \"expected\": [\"\\\"a\", \"b\\\"\"], \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": [\"a\\\\\\\\b\"], \"expected\": [\"a\\\\b\"], \"passed\": false}, {\"check\": \"boundary 4\", \"actual\": [\"a\", \"\", \"\"], \"expected\": [\"a\", \"\", \"\"], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":59.54,"exit_code":0,"observations":[{"actual":["a,b","c"],"check":"boundary 1","expected":["a,b","c"],"passed":true},{"actual":["\"a","b\""],"check":"boundary 2","expected":["\"a","b\""],"passed":true},{"actual":["a\\b"],"check":"boundary 3","expected":["a\\b"],"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\", \"b\\\"\"], \"expected\": [\"\\\"a\", \"b\\\"\"], \"passed\": true}, {\"check\": \"boundary 3\", \"actual\": [\"a\\\\b\"], \"expected\": [\"a\\\\b\"], \"passed\": true}, {\"check\": \"boundary 4\", \"actual\": [\"a\", \"\", \"\"], \"expected\": [\"a\", \"\", \"\"], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}