FA-3296 / Delimited text / Open access

A semicolon inside a query value becomes a separator · case 01

A semicolon inside a query value becomes a separator.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The implementation applies an operation whose text or grammar semantics violate this contract: Decode ampersand-separated form fields; semicolons are ordinary data.

VERIFIED REPAIR

Implement the complete stated contract, including the boundary fixtures: Decode ampersand-separated form fields; semicolons are ordinary data.

Unsuccessful approach: The attempted repair handles the primary example but still violates a separate boundary of the same contract.

Case contract

Decode ampersand-separated form fields; semicolons are ordinary data.

Why this case matters

A local executable model for consumers of structured text; oracle values are authored literals, not outputs copied from the repaired implementation.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct
from urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit
from email.header import decode_header, make_header
from email.utils import getaddresses
from xml.etree import ElementTree as ET
import shlex, string, textwrap

N = 1
observations = []
def solve(x):
    try:
        return [list(p) for p in parse_qsl(x.replace(';','&'),keep_blank_values=True)]
    except Exception as exc:
        return {"error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('boundary 1', solve('a=1;b=2'), [['a', '1;b=2']])
check('boundary 2', solve('a=1&b=2'), [['a', '1'], ['b', '2']])
check('boundary 3', solve('x=;'), [['x', ';']])
check('boundary 4', solve(''), [])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
boundary 1	`[['a', '1'], ['b', '2']]`	`[['a', '1;b=2']]`	Failed
boundary 2	`[['a', '1'], ['b', '2']]`	`[['a', '1'], ['b', '2']]`	Passed
boundary 3	`[['x', '']]`	`[['x', ';']]`	Failed
boundary 4	`[]`	`[]`	Passed

SHA-256 / d6448de61dbeb2be9452f570b6f32fbc3afd25dd07cc443ad894cae40504a7d2

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct
from urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit
from email.header import decode_header, make_header
from email.utils import getaddresses
from xml.etree import ElementTree as ET
import shlex, string, textwrap

N = 1
observations = []
def solve(x):
    try:
        return [list(p) for p in parse_qsl(x,separator=';',keep_blank_values=True)]
    except Exception as exc:
        return {"error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('boundary 1', solve('a=1;b=2'), [['a', '1;b=2']])
check('boundary 2', solve('a=1&b=2'), [['a', '1'], ['b', '2']])
check('boundary 3', solve('x=;'), [['x', ';']])
check('boundary 4', solve(''), [])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
boundary 1	`[['a', '1'], ['b', '2']]`	`[['a', '1;b=2']]`	Failed
boundary 2	`[['a', '1&b=2']]`	`[['a', '1'], ['b', '2']]`	Failed
boundary 3	`[['x', '']]`	`[['x', ';']]`	Failed
boundary 4	`[]`	`[]`	Passed

SHA-256 / fdddc648f256f92c08c50cedade49ed3d666ee87c3e28be124bea5eb1712d513

3 / The verified repair

Exit 0

"""Failure Map reference implementation. Python standard library only."""
import json
import re, unicodedata, json, csv, io, html, base64, binascii, codecs, struct
from urllib.parse import quote, unquote, unquote_to_bytes, urlencode, parse_qsl, urlsplit, urlunsplit
from email.header import decode_header, make_header
from email.utils import getaddresses
from xml.etree import ElementTree as ET
import shlex, string, textwrap

N = 1
observations = []
def solve(x):
    try:
        return [list(p) for p in parse_qsl(x,separator='&',keep_blank_values=True)]
    except Exception as exc:
        return {"error": type(exc).__name__}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('boundary 1', solve('a=1;b=2'), [['a', '1;b=2']])
check('boundary 2', solve('a=1&b=2'), [['a', '1'], ['b', '2']])
check('boundary 3', solve('x=;'), [['x', ';']])
check('boundary 4', solve(''), [])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
boundary 1	`[['a', '1;b=2']]`	`[['a', '1;b=2']]`	Passed
boundary 2	`[['a', '1'], ['b', '2']]`	`[['a', '1'], ['b', '2']]`	Passed
boundary 3	`[['x', ';']]`	`[['x', ';']]`	Passed
boundary 4	`[]`	`[]`	Passed

SHA-256 / 2f8166463772e55e91f2297d1f4c2df66d7663564510b39f8db584c19a244eb1

Verification & scope

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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:37:24.053749+00:00.

Case digest / 6a29a9f767c362e4fb20d08808ad7686f10ad5860490b26ad82aa0a489c16640