FAILURE MAP
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FA-3996 / Markup / Open access

CDATA serialization emits an embedded terminator · case 01

CDATA serialization emits an embedded terminator.

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: Wrap text in CDATA, splitting embedded ]]> across adjacent CDATA sections.

VERIFIED REPAIR

Implement the complete stated contract, including the boundary fixtures: Wrap text in CDATA, splitting embedded ]]> across adjacent CDATA sections.

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

Case contract

Wrap text in CDATA, splitting embedded ]]> across adjacent CDATA sections.

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 '<![CDATA['+x+']]>'
    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]]>b'), '<![CDATA[a]]]]><![CDATA[>b]]>')
check('boundary 2', solve('x'), '<![CDATA[x]]>')
check('boundary 3', solve(''), '<![CDATA[]]>')
check('boundary 4', solve(']]>]]>'), '<![CDATA[]]]]><![CDATA[>]]]]><![CDATA[>]]>')
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 fixtureActualExpectedOutcome
boundary 1<![CDATA[a]]>b]]><![CDATA[a]]]]><![CDATA[>b]]>Failed
boundary 2<![CDATA[x]]><![CDATA[x]]>Passed
boundary 3<![CDATA[]]><![CDATA[]]>Passed
boundary 4<![CDATA[]]>]]>]]><![CDATA[]]]]><![CDATA[>]]]]><![CDATA[>]]>Failed

SHA-256 / 1cae7d188df5d5c254910ac97f1664d8eefbc93aec6069c5d0fecdbdc07fc82b

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 '<![CDATA['+x.replace(']]>','')+']]>'
    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]]>b'), '<![CDATA[a]]]]><![CDATA[>b]]>')
check('boundary 2', solve('x'), '<![CDATA[x]]>')
check('boundary 3', solve(''), '<![CDATA[]]>')
check('boundary 4', solve(']]>]]>'), '<![CDATA[]]]]><![CDATA[>]]]]><![CDATA[>]]>')
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 fixtureActualExpectedOutcome
boundary 1<![CDATA[ab]]><![CDATA[a]]]]><![CDATA[>b]]>Failed
boundary 2<![CDATA[x]]><![CDATA[x]]>Passed
boundary 3<![CDATA[]]><![CDATA[]]>Passed
boundary 4<![CDATA[]]><![CDATA[]]]]><![CDATA[>]]]]><![CDATA[>]]>Failed

SHA-256 / 5e5b2da60f09f1711920db75c09bbd08a402036400f813f7713fe74c609d919d

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 '<![CDATA['+x.replace(']]>',']]]]><![CDATA[>')+']]>'
    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]]>b'), '<![CDATA[a]]]]><![CDATA[>b]]>')
check('boundary 2', solve('x'), '<![CDATA[x]]>')
check('boundary 3', solve(''), '<![CDATA[]]>')
check('boundary 4', solve(']]>]]>'), '<![CDATA[]]]]><![CDATA[>]]]]><![CDATA[>]]>')
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 fixtureActualExpectedOutcome
boundary 1<![CDATA[a]]]]><![CDATA[>b]]><![CDATA[a]]]]><![CDATA[>b]]>Passed
boundary 2<![CDATA[x]]><![CDATA[x]]>Passed
boundary 3<![CDATA[]]><![CDATA[]]>Passed
boundary 4<![CDATA[]]]]><![CDATA[>]]]]><![CDATA[>]]><![CDATA[]]]]><![CDATA[>]]]]><![CDATA[>]]>Passed

SHA-256 / 9cbfd7d0648feaa6e55bca8dc20c19958e58a336e66f41468e6c71803475c66c

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 2026-09-29T14:37:34.195949+00:00.

Case digest / a4a7bd0405d21c4257874ad80d3c1fd08075dca905977f50ee16002100558815