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FA-26376 / HTTP ranges / Open access

An explicit nonmatching entity condition takes precedence over a matching date · case 01

An explicit nonmatching entity condition takes precedence over a matching date.

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

ROOT CAUSE

The if-none-match-suppresses-date decision uses return [304, ""] if tag_hit or date_hit else [206,part].

VERIFIED REPAIR

Apply the bounded decision exactly: hit = tag_hit if tags_present else date_hit return [304, ""] if hit else [206,part]

Unsuccessful approach: The partial repair uses return [304, ""] if tag_hit else [206,part], which still violates the stated contract.

Case contract

For this GET model use tag_hit whenever a tag condition was present, otherwise date_hit. Return [304,empty] or [206,part].

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(tags_present, tag_hit, date_hit, part):
    return [304, ""] if tag_hit or date_hit else [206,part]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('if-none-match-suppresses-date fixture 0', solve(True,False,True,"p"*N), [206,"p"*N])
check('if-none-match-suppresses-date fixture 1', solve(False,False,True,"p"), [304,""])
check('if-none-match-suppresses-date fixture 2', solve(True,True,False,"p"), [304,""])
check('if-none-match-suppresses-date fixture 3', solve(True,False,False,"p"*N), [206,"p"*N])
check('if-none-match-suppresses-date fixture 4', solve(False,False,False,"p"), [206,"p"])
check('if-none-match-suppresses-date fixture 5', solve(False,True,False,"p"), [206,"p"])
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
if-none-match-suppresses-date fixture 0[304, ''][206, 'p']Failed
if-none-match-suppresses-date fixture 1[304, ''][304, '']Passed
if-none-match-suppresses-date fixture 2[304, ''][304, '']Passed
if-none-match-suppresses-date fixture 3[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 4[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 5[304, ''][206, 'p']Failed

SHA-256 / 5cd6736c9b030c2e5821ec4ad5075aa40dd49514a65c846551bd58df9ae24cee

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(tags_present, tag_hit, date_hit, part):
    return [304, ""] if tag_hit else [206,part]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('if-none-match-suppresses-date fixture 0', solve(True,False,True,"p"*N), [206,"p"*N])
check('if-none-match-suppresses-date fixture 1', solve(False,False,True,"p"), [304,""])
check('if-none-match-suppresses-date fixture 2', solve(True,True,False,"p"), [304,""])
check('if-none-match-suppresses-date fixture 3', solve(True,False,False,"p"*N), [206,"p"*N])
check('if-none-match-suppresses-date fixture 4', solve(False,False,False,"p"), [206,"p"])
check('if-none-match-suppresses-date fixture 5', solve(False,True,False,"p"), [206,"p"])
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
if-none-match-suppresses-date fixture 0[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 1[206, 'p'][304, '']Failed
if-none-match-suppresses-date fixture 2[304, ''][304, '']Passed
if-none-match-suppresses-date fixture 3[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 4[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 5[304, ''][206, 'p']Failed

SHA-256 / 34889cf0239e466091775274ad6624582f17b9816e9f6e5be14b12a68781b474

3 / The verified repair

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

N = 1
observations = []
def solve(tags_present, tag_hit, date_hit, part):
    hit = tag_hit if tags_present else date_hit
    return [304, ""] if hit else [206,part]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('if-none-match-suppresses-date fixture 0', solve(True,False,True,"p"*N), [206,"p"*N])
check('if-none-match-suppresses-date fixture 1', solve(False,False,True,"p"), [304,""])
check('if-none-match-suppresses-date fixture 2', solve(True,True,False,"p"), [304,""])
check('if-none-match-suppresses-date fixture 3', solve(True,False,False,"p"*N), [206,"p"*N])
check('if-none-match-suppresses-date fixture 4', solve(False,False,False,"p"), [206,"p"])
check('if-none-match-suppresses-date fixture 5', solve(False,True,False,"p"), [206,"p"])
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
if-none-match-suppresses-date fixture 0[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 1[304, ''][304, '']Passed
if-none-match-suppresses-date fixture 2[304, ''][304, '']Passed
if-none-match-suppresses-date fixture 3[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 4[206, 'p'][206, 'p']Passed
if-none-match-suppresses-date fixture 5[206, 'p'][206, 'p']Passed

SHA-256 / 3a84bb4eca2e665c4a234dcb9e3f3338fd8b443d4daf0211d4944b31fc742bb1

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 2026-09-29T14:41:15.494558+00:00.

Case digest / 5b258f4b5fad336fcc8469ac8b138a6a39089b26ab1f26e45479f3f4d5f4f104