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Canonical combining marks remain out of order · case 01

Canonical combining marks remain out of order.

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: Normalize to NFC, preserving compatibility characters.

VERIFIED REPAIR

Implement the complete stated contract, including the boundary fixtures: Normalize to NFC, preserving compatibility characters.

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

Case contract

Normalize to NFC, preserving compatibility characters.

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 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('à̕'), 'à̕')
check('boundary 2', solve('é'), 'é')
check('boundary 3', solve('①'), '①')
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	`à̕`	`à̕`	Failed
boundary 2	`é`	`é`	Failed
boundary 3	`①`	`①`	Passed
boundary 4			Passed

SHA-256 / 920075436d022250ce821730dfe3f8f40930886005df48d0ec8f176d91270f04

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 unicodedata.normalize('NFD', 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('à̕'), 'à̕')
check('boundary 2', solve('é'), 'é')
check('boundary 3', solve('①'), '①')
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	`à̕`	`à̕`	Failed
boundary 2	`é`	`é`	Failed
boundary 3	`①`	`①`	Passed
boundary 4			Passed

SHA-256 / 8bd8b4ffff4f5a71573a39328b49ff66b36c2c752ebde12a633186f52c688f6a

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 unicodedata.normalize('NFC', 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('à̕'), 'à̕')
check('boundary 2', solve('é'), 'é')
check('boundary 3', solve('①'), '①')
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	`à̕`	`à̕`	Passed
boundary 2	`é`	`é`	Passed
boundary 3	`①`	`①`	Passed
boundary 4			Passed

SHA-256 / 32760431a4174cfbb7e753ae1e3a1542580a0d65fa7d2a41ba3db9e514cd094e

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 2026-09-29T14:37:17.970098+00:00.

Case digest / e6992208405e20b81281474e42d620b06e5dc36cd2384617043ae678e586ea07