FAILURE MAP
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FA-26836 / HTTP ranges / Open access

Range body whitespace remains byte-exact after framing removal · case 01

Range body whitespace remains byte-exact after framing removal.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The multipart-client-body-not-strip decision uses return framed.strip().

VERIFIED REPAIR

Apply the bounded decision exactly: return framed[:-2]

Unsuccessful approach: The partial repair uses return framed.rstrip("\r\n"), which still violates the stated contract.

Case contract

framed ends with exactly one framing CRLF. Return all preceding payload bytes; do not trim payload whitespace.

Why this case matters

Range responses combine representation identity, conditional requests, framing, and partial-object state.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(framed):
    return framed.strip()
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('multipart-client-body-not-strip fixture 0', solve("p"*N+"\r\n\r\n"), "p"*N+"\r\n")
check('multipart-client-body-not-strip fixture 1', solve(" p \r\n"), " p ")
check('multipart-client-body-not-strip fixture 2', solve("\r\n"), "")
check('multipart-client-body-not-strip fixture 3', solve("p\r\n"), "p")
check('multipart-client-body-not-strip fixture 4', solve("p\n\r\n"), "p\n")
check('multipart-client-body-not-strip fixture 5', solve("p\r\r\n"), "p\r")
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
multipart-client-body-not-strip fixture 0pp Failed
multipart-client-body-not-strip fixture 1p p Failed
multipart-client-body-not-strip fixture 2Passed
multipart-client-body-not-strip fixture 3ppPassed
multipart-client-body-not-strip fixture 4pp Failed
multipart-client-body-not-strip fixture 5pp Failed

SHA-256 / 6ae413270fa264e97789d05acb680f858a244d646900cd0034a296b83844506c

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(framed):
    return framed.rstrip("\r\n")
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('multipart-client-body-not-strip fixture 0', solve("p"*N+"\r\n\r\n"), "p"*N+"\r\n")
check('multipart-client-body-not-strip fixture 1', solve(" p \r\n"), " p ")
check('multipart-client-body-not-strip fixture 2', solve("\r\n"), "")
check('multipart-client-body-not-strip fixture 3', solve("p\r\n"), "p")
check('multipart-client-body-not-strip fixture 4', solve("p\n\r\n"), "p\n")
check('multipart-client-body-not-strip fixture 5', solve("p\r\r\n"), "p\r")
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
multipart-client-body-not-strip fixture 0pp Failed
multipart-client-body-not-strip fixture 1 p p Passed
multipart-client-body-not-strip fixture 2Passed
multipart-client-body-not-strip fixture 3ppPassed
multipart-client-body-not-strip fixture 4pp Failed
multipart-client-body-not-strip fixture 5pp Failed

SHA-256 / 3482a9129a26b9c26eaa143ed903f22ba1770a92e4eb7cbfcb0e0e74aa22c0c7

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(framed):
    return framed[:-2]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('multipart-client-body-not-strip fixture 0', solve("p"*N+"\r\n\r\n"), "p"*N+"\r\n")
check('multipart-client-body-not-strip fixture 1', solve(" p \r\n"), " p ")
check('multipart-client-body-not-strip fixture 2', solve("\r\n"), "")
check('multipart-client-body-not-strip fixture 3', solve("p\r\n"), "p")
check('multipart-client-body-not-strip fixture 4', solve("p\n\r\n"), "p\n")
check('multipart-client-body-not-strip fixture 5', solve("p\r\r\n"), "p\r")
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
multipart-client-body-not-strip fixture 0p p Passed
multipart-client-body-not-strip fixture 1 p p Passed
multipart-client-body-not-strip fixture 2Passed
multipart-client-body-not-strip fixture 3ppPassed
multipart-client-body-not-strip fixture 4p p Passed
multipart-client-body-not-strip fixture 5p p Passed

SHA-256 / 9f8e7b7d52f7f614f213272c3517b9a5a903d7c553aa795b7cc8a2fc055cb7ad

Verification & scope

Deterministic simplified range service, with stipulated local policies and already parsed trusted inputs; not a complete HTTP implementation. 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 2026-09-29T14:41:19.490887+00:00.

Case digest / 932b585b584cb9903d561c4cbd9c886e7393ba8b74f65136c5e409b2e43d9bf2