FA-26381 / HTTP ranges / Open access
Successful entity preconditions suppress a stale secondary date condition · case 01
Successful entity preconditions suppress a stale secondary date condition.
ROOT CAUSE
The if-match-suppresses-unmodified-date decision uses return [206,part] if tag_ok and date_ok else [412,""].
VERIFIED REPAIR
Apply the bounded decision exactly: ok = tag_ok if tag_present else date_ok return [206,part] if ok else [412,""]
Unsuccessful approach: The partial repair uses return [206,part] if tag_ok else [412,""], which still violates the stated contract.
Case contract
If tag condition is present, its result alone decides 412; otherwise the unmodified-date condition decides. Accepted output is [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(tag_present, tag_ok, date_ok, part):
return [206,part] if tag_ok and date_ok else [412,""]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('if-match-suppresses-unmodified-date fixture 0', solve(True,True,False,"p"*N), [206,"p"*N])
check('if-match-suppresses-unmodified-date fixture 1', solve(False,False,True,"p"*N), [206,"p"*N])
check('if-match-suppresses-unmodified-date fixture 2', solve(True,False,True,"p"), [412,""])
check('if-match-suppresses-unmodified-date fixture 3', solve(False,True,False,"p"), [412,""])
check('if-match-suppresses-unmodified-date fixture 4', solve(True,True,True,"p"), [206,"p"])
check('if-match-suppresses-unmodified-date fixture 5', solve(False,False,False,""), [412,""])
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 |
|---|---|---|---|
| if-match-suppresses-unmodified-date fixture 0 | [412, ''] | [206, 'p'] | Failed |
| if-match-suppresses-unmodified-date fixture 1 | [412, ''] | [206, 'p'] | Failed |
| if-match-suppresses-unmodified-date fixture 2 | [412, ''] | [412, ''] | Passed |
| if-match-suppresses-unmodified-date fixture 3 | [412, ''] | [412, ''] | Passed |
| if-match-suppresses-unmodified-date fixture 4 | [206, 'p'] | [206, 'p'] | Passed |
| if-match-suppresses-unmodified-date fixture 5 | [412, ''] | [412, ''] | Passed |
SHA-256 / 1c85145dac0f0a110bd3ff21d5046e14713e38d0dc64d02cf5e242eed3dbe40c
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(tag_present, tag_ok, date_ok, part):
return [206,part] if tag_ok else [412,""]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('if-match-suppresses-unmodified-date fixture 0', solve(True,True,False,"p"*N), [206,"p"*N])
check('if-match-suppresses-unmodified-date fixture 1', solve(False,False,True,"p"*N), [206,"p"*N])
check('if-match-suppresses-unmodified-date fixture 2', solve(True,False,True,"p"), [412,""])
check('if-match-suppresses-unmodified-date fixture 3', solve(False,True,False,"p"), [412,""])
check('if-match-suppresses-unmodified-date fixture 4', solve(True,True,True,"p"), [206,"p"])
check('if-match-suppresses-unmodified-date fixture 5', solve(False,False,False,""), [412,""])
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 |
|---|---|---|---|
| if-match-suppresses-unmodified-date fixture 0 | [206, 'p'] | [206, 'p'] | Passed |
| if-match-suppresses-unmodified-date fixture 1 | [412, ''] | [206, 'p'] | Failed |
| if-match-suppresses-unmodified-date fixture 2 | [412, ''] | [412, ''] | Passed |
| if-match-suppresses-unmodified-date fixture 3 | [206, 'p'] | [412, ''] | Failed |
| if-match-suppresses-unmodified-date fixture 4 | [206, 'p'] | [206, 'p'] | Passed |
| if-match-suppresses-unmodified-date fixture 5 | [412, ''] | [412, ''] | Passed |
SHA-256 / 5a3b3dfdd9898f3b664ec7418348718cd64b4ef8f1e54d55b1003ac86bb107b2
3 / The verified repair
Exit 0"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(tag_present, tag_ok, date_ok, part):
ok = tag_ok if tag_present else date_ok
return [206,part] if ok else [412,""]
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('if-match-suppresses-unmodified-date fixture 0', solve(True,True,False,"p"*N), [206,"p"*N])
check('if-match-suppresses-unmodified-date fixture 1', solve(False,False,True,"p"*N), [206,"p"*N])
check('if-match-suppresses-unmodified-date fixture 2', solve(True,False,True,"p"), [412,""])
check('if-match-suppresses-unmodified-date fixture 3', solve(False,True,False,"p"), [412,""])
check('if-match-suppresses-unmodified-date fixture 4', solve(True,True,True,"p"), [206,"p"])
check('if-match-suppresses-unmodified-date fixture 5', solve(False,False,False,""), [412,""])
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 |
|---|---|---|---|
| if-match-suppresses-unmodified-date fixture 0 | [206, 'p'] | [206, 'p'] | Passed |
| if-match-suppresses-unmodified-date fixture 1 | [206, 'p'] | [206, 'p'] | Passed |
| if-match-suppresses-unmodified-date fixture 2 | [412, ''] | [412, ''] | Passed |
| if-match-suppresses-unmodified-date fixture 3 | [412, ''] | [412, ''] | Passed |
| if-match-suppresses-unmodified-date fixture 4 | [206, 'p'] | [206, 'p'] | Passed |
| if-match-suppresses-unmodified-date fixture 5 | [412, ''] | [412, ''] | Passed |
SHA-256 / 952f2121587b6bb73d922e88e9d1b8ae7a2f5856f32a67d31ce92721dfe752bb
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 2026-09-29T14:41:15.589128+00:00.
Case digest / ba071c55f853d0da6d3afd80a8b9cd6220bee0f2dee526a7377e708b1474e9b1