FA-3171 / Serialization / Open access
Repeated object members disappear from an ordered representation · case 01
Repeated object members disappear from an ordered representation.
ROOT CAUSE
The implementation applies an operation whose text or grammar semantics violate this contract: Decode every JSON object to its ordered list of member pairs, preserving duplicates.
VERIFIED REPAIR
Implement the complete stated contract, including the boundary fixtures: Decode every JSON object to its ordered list of member pairs, preserving duplicates.
Unsuccessful approach: The attempted repair handles the primary example but still violates a separate boundary of the same contract.
Case contract
Decode every JSON object to its ordered list of member pairs, preserving duplicates.
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 json.loads(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":1,"a":2}'), [['a', 1], ['a', 2]])
check('boundary 2', solve('{"x":{"z":0}}'), [['x', [['z', 0]]]])
check('boundary 3', solve('{}'), [])
check('boundary 4', solve('{"b":2,"a":1}'), [['b', 2], ['a', 1]])
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': 2} | [['a', 1], ['a', 2]] | Failed |
| boundary 2 | {'x': {'z': 0}} | [['x', [['z', 0]]]] | Failed |
| boundary 3 | {} | [] | Failed |
| boundary 4 | {'a': 1, 'b': 2} | [['b', 2], ['a', 1]] | Failed |
SHA-256 / 0e0528e22bb442cf48dc8f266e0ef58b9becc6497d1fd3e4d3db171885ca406b
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(json.loads(x).items())
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,"a":2}'), [['a', 1], ['a', 2]])
check('boundary 2', solve('{"x":{"z":0}}'), [['x', [['z', 0]]]])
check('boundary 3', solve('{}'), [])
check('boundary 4', solve('{"b":2,"a":1}'), [['b', 2], ['a', 1]])
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', 2]] | [['a', 1], ['a', 2]] | Failed |
| boundary 2 | [['x', {'z': 0}]] | [['x', [['z', 0]]]] | Failed |
| boundary 3 | [] | [] | Passed |
| boundary 4 | [['b', 2], ['a', 1]] | [['b', 2], ['a', 1]] | Failed |
SHA-256 / 253abb8e4832654d9bc5a6eff0eca9dd5b329d3a0b639210286721bf6ba52308
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 json.loads(x,object_pairs_hook=lambda pairs:[list(p) for p in pairs])
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,"a":2}'), [['a', 1], ['a', 2]])
check('boundary 2', solve('{"x":{"z":0}}'), [['x', [['z', 0]]]])
check('boundary 3', solve('{}'), [])
check('boundary 4', solve('{"b":2,"a":1}'), [['b', 2], ['a', 1]])
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], ['a', 2]] | [['a', 1], ['a', 2]] | Passed |
| boundary 2 | [['x', [['z', 0]]]] | [['x', [['z', 0]]]] | Passed |
| boundary 3 | [] | [] | Passed |
| boundary 4 | [['b', 2], ['a', 1]] | [['b', 2], ['a', 1]] | Passed |
SHA-256 / 142747fec4e85c219c5bc84da5a1161be3ae2b0b4ede14df156f229fb356e7d5
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 2026-09-29T14:37:22.260764+00:00.
Case digest / 9d0118d68735bf0c9c02a3819b9b725902d82017a5989e930c655c51825507df