FA-26506 / HTTP ranges / Open access

Fragment admission rejects a conflicting complete length · case 01

Fragment admission rejects a conflicting complete length.

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

ROOT CAUSE

The cache-total-length-disagreement decision uses return [incoming,body].

THE FAILURE

The cache-total-length-disagreement decision uses return [incoming,body].

Unsuccessful approach: The partial repair uses return [max(known or 0,incoming or 0),body], which still violates the stated contract.

Case contract

Known and incoming complete lengths are integer or None. Reject conflicting known lengths; otherwise return [resolved-length,body].

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(known, incoming, body):
    return [incoming,body]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('cache-total-length-disagreement fixture 0', solve(N,N+1,"p"*N), None)
check('cache-total-length-disagreement fixture 1', solve(N,None,"p"), [N,"p"])
check('cache-total-length-disagreement fixture 2', solve(None,N,"p"), [N,"p"])
check('cache-total-length-disagreement fixture 3', solve(None,None,""), [None,""])
check('cache-total-length-disagreement fixture 4', solve(0,0,""), [0,""])
check('cache-total-length-disagreement fixture 5', solve(N,N,"p"*N), [N,"p"*N])
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
cache-total-length-disagreement fixture 0	`[2, 'p']`	`None`	Failed
cache-total-length-disagreement fixture 1	`[None, 'p']`	`[1, 'p']`	Failed
cache-total-length-disagreement fixture 2	`[1, 'p']`	`[1, 'p']`	Passed
cache-total-length-disagreement fixture 3	`[None, '']`	`[None, '']`	Passed
cache-total-length-disagreement fixture 4	`[0, '']`	`[0, '']`	Passed
cache-total-length-disagreement fixture 5	`[1, 'p']`	`[1, 'p']`	Passed

SHA-256 / a9b24ab6f389b8cd23a283460ef488e703a3904c540c8013319e4d0f75178057

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(known, incoming, body):
    return [max(known or 0,incoming or 0),body]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('cache-total-length-disagreement fixture 0', solve(N,N+1,"p"*N), None)
check('cache-total-length-disagreement fixture 1', solve(N,None,"p"), [N,"p"])
check('cache-total-length-disagreement fixture 2', solve(None,N,"p"), [N,"p"])
check('cache-total-length-disagreement fixture 3', solve(None,None,""), [None,""])
check('cache-total-length-disagreement fixture 4', solve(0,0,""), [0,""])
check('cache-total-length-disagreement fixture 5', solve(N,N,"p"*N), [N,"p"*N])
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
cache-total-length-disagreement fixture 0	`[2, 'p']`	`None`	Failed
cache-total-length-disagreement fixture 1	`[1, 'p']`	`[1, 'p']`	Passed
cache-total-length-disagreement fixture 2	`[1, 'p']`	`[1, 'p']`	Passed
cache-total-length-disagreement fixture 3	`[0, '']`	`[None, '']`	Failed
cache-total-length-disagreement fixture 4	`[0, '']`	`[0, '']`	Passed
cache-total-length-disagreement fixture 5	`[1, 'p']`	`[1, 'p']`	Passed

SHA-256 / b3a62e06cb01263bdcd10f214a9fd8ad690c3d6d0b1321be2af07ff9937b5273

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 6 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

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 2026-09-29T14:41:16.577447+00:00.

Case digest / b06ea86eae881b15f663f3b1ab4191e943e7d9354898cbd779b8a974128785e4