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JSON Pointer escape replacement runs in reverse order · case 01

JSON Pointer escape replacement runs in reverse 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: Decode a single JSON Pointer token: ~1 becomes slash, then ~0 becomes tilde.

VERIFIED REPAIR

Implement the complete stated contract, including the boundary fixtures: Decode a single JSON Pointer token: ~1 becomes slash, then ~0 becomes tilde.

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

Case contract

Decode a single JSON Pointer token: ~1 becomes slash, then ~0 becomes tilde.

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.replace('~0','~').replace('~1','/')
    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('~01'), '~1')
check('boundary 2', solve('a~1b'), 'a/b')
check('boundary 3', solve('~0'), '~')
check('boundary 4', solve('x'), 'x')
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/~1Failed
boundary 2a/ba/bPassed
boundary 3~~Passed
boundary 4xxPassed

SHA-256 / 7055617d58194a6b5f22f783ee42657974baf414c1e1efc141422212a702bad2

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 x.replace('~1','/')
    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('~01'), '~1')
check('boundary 2', solve('a~1b'), 'a/b')
check('boundary 3', solve('~0'), '~')
check('boundary 4', solve('x'), 'x')
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 1~01~1Failed
boundary 2a/ba/bPassed
boundary 3~0~Failed
boundary 4xxPassed

SHA-256 / 27394cec4a5240d7dba1e9cc72be788a15a1ddfe3fd93c494526db4e8f980de7

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 x.replace('~1','/').replace('~0','~')
    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('~01'), '~1')
check('boundary 2', solve('a~1b'), 'a/b')
check('boundary 3', solve('~0'), '~')
check('boundary 4', solve('x'), 'x')
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 1~1~1Passed
boundary 2a/ba/bPassed
boundary 3~~Passed
boundary 4xxPassed

SHA-256 / 9cc6204740c30d36a84462b3c7bdfb7baeea34b09ef76a685182063e718546f3

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 2026-09-29T14:37:22.265807+00:00.

Case digest / 6625a43aac8e122c272b6228c3676858313cf67a3fa2a9dd98a7e52c245d5e31