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FA-3056 / Text processing / Open access

Indent removal destroys relative indentation · case 01

Indent removal destroys relative indentation.

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: Remove the common whitespace indentation from nonblank lines using textwrap.dedent.

VERIFIED REPAIR

Implement the complete stated contract, including the boundary fixtures: Remove the common whitespace indentation from nonblank lines using textwrap.dedent.

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

Case contract

Remove the common whitespace indentation from nonblank lines using textwrap.dedent.

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 '\n'.join(v.lstrip() for v in x.split('\n'))
    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\n    b'), 'a\n  b')
check('boundary 2', solve(' a\n b'), 'a\nb')
check('boundary 3', solve('a\n b'), 'a\n b')
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 fixtureActualExpectedOutcome
boundary 1a ba bFailed
boundary 2a ba bPassed
boundary 3a ba bFailed
boundary 4Passed

SHA-256 / 40a9c3935dc2161f887f1e4cddb3f0ee0c5a68692d964472310d06d8d68eb208

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 '\n'.join(v[2:] for v in x.split('\n'))
    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\n    b'), 'a\n  b')
check('boundary 2', solve(' a\n b'), 'a\nb')
check('boundary 3', solve('a\n b'), 'a\n b')
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 fixtureActualExpectedOutcome
boundary 1a ba bPassed
boundary 2 a bFailed
boundary 3 a bFailed
boundary 4Passed

SHA-256 / 748bccfedd573c79584ac034f9e0e059436e325ec9ef0239a9ed400c23e828c0

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 textwrap.dedent(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\n    b'), 'a\n  b')
check('boundary 2', solve(' a\n b'), 'a\nb')
check('boundary 3', solve('a\n b'), 'a\n b')
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 fixtureActualExpectedOutcome
boundary 1a ba bPassed
boundary 2a ba bPassed
boundary 3a ba bPassed
boundary 4Passed

SHA-256 / c646594857bd565c52c2c5bb151c3f4c4540848c29d61e6572e31e8b6f43b305

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 2026-09-29T14:37:20.817141+00:00.

Case digest / 9cea5eefb986c8779b2b3cefd620a380460fda8f1335efb6903cde1ec364ad8e