FAILURE MAP
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FA-3161 / Serialization / Open access

A valid null is confused with parse failure · case 01

A valid null is confused with parse failure.

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: Return an ok/value envelope on JSON success, and ok false for malformed input.

VERIFIED REPAIR

Implement the complete stated contract, including the boundary fixtures: Return an ok/value envelope on JSON success, and ok false for malformed input.

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

Case contract

Return an ok/value envelope on JSON success, and ok false for malformed input.

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:
        try:
            v=json.loads(x)
            return {'ok':bool(v),'value':v}
        except ValueError:
            return {'ok':False}
    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('null'), {'ok': True, 'value': None})
check('boundary 2', solve('0'), {'ok': True, 'value': 0})
check('boundary 3', solve('false'), {'ok': True, 'value': False})
check('boundary 4', solve('{'), {'ok': False})
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{'ok': False, 'value': None}{'ok': True, 'value': None}Failed
boundary 2{'ok': False, 'value': 0}{'ok': True, 'value': 0}Failed
boundary 3{'ok': False, 'value': False}{'ok': True, 'value': False}Failed
boundary 4{'ok': False}{'ok': False}Passed

SHA-256 / 4d850e992f6d7451ffdf28d9b298425fcc0d16aceab7c4fdbd58add772eb90bb

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:
        try:
            v=json.loads(x)
            return {'ok':v is not None,'value':v}
        except ValueError:
            return {'ok':False}
    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('null'), {'ok': True, 'value': None})
check('boundary 2', solve('0'), {'ok': True, 'value': 0})
check('boundary 3', solve('false'), {'ok': True, 'value': False})
check('boundary 4', solve('{'), {'ok': False})
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{'ok': False, 'value': None}{'ok': True, 'value': None}Failed
boundary 2{'ok': True, 'value': 0}{'ok': True, 'value': 0}Passed
boundary 3{'ok': True, 'value': False}{'ok': True, 'value': False}Passed
boundary 4{'ok': False}{'ok': False}Passed

SHA-256 / 17fe854bb648e233d2d0aae6c4b253edd20196aec0412bdd6d26547f574fa5b2

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:
        try:
            return {'ok':True,'value':json.loads(x)}
        except ValueError:
            return {'ok':False}
    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('null'), {'ok': True, 'value': None})
check('boundary 2', solve('0'), {'ok': True, 'value': 0})
check('boundary 3', solve('false'), {'ok': True, 'value': False})
check('boundary 4', solve('{'), {'ok': False})
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{'ok': True, 'value': None}{'ok': True, 'value': None}Passed
boundary 2{'ok': True, 'value': 0}{'ok': True, 'value': 0}Passed
boundary 3{'ok': True, 'value': False}{'ok': True, 'value': False}Passed
boundary 4{'ok': False}{'ok': False}Passed

SHA-256 / cfc259c75114a46c736894f10b3ecc3a7e0552c1d3ee06c9b62ff15cc58f2a0f

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 2026-09-29T14:37:22.196081+00:00.

Case digest / 3a4f299a9121ab3b83346574210a0c8ca5e85738ece51194f04a0679e6ff0f07