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FA-26671 / HTTP ranges / Open access

Request member limits apply before deduplication · case 01

Request member limits apply before deduplication.

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

ROOT CAUSE

The range-count-before-coalescing decision uses return "accept" if len(set(members))<=limit else "reject".

VERIFIED REPAIR

Apply the bounded decision exactly: return "accept" if len(members)<=limit else "reject"

Unsuccessful approach: The partial repair uses return "accept" if len(members)<limit else "reject", which still violates the stated contract.

Case contract

Return accept iff raw parsed member count<=limit, reject otherwise; repeated ranges still consume parser budget.

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(members, limit):
    return "accept" if len(set(members))<=limit else "reject"
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('range-count-before-coalescing fixture 0', solve( ["0-1"]*(N+1),N), "reject")
check('range-count-before-coalescing fixture 1', solve(["0-1"]*N,N), "accept")
check('range-count-before-coalescing fixture 2', solve([],0), "accept")
check('range-count-before-coalescing fixture 3', solve(["0-1"],0), "reject")
check('range-count-before-coalescing fixture 4', solve(["0-1","2-3"],2), "accept")
check('range-count-before-coalescing fixture 5', solve(["0-1"],3), "accept")
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
range-count-before-coalescing fixture 0acceptrejectFailed
range-count-before-coalescing fixture 1acceptacceptPassed
range-count-before-coalescing fixture 2acceptacceptPassed
range-count-before-coalescing fixture 3rejectrejectPassed
range-count-before-coalescing fixture 4acceptacceptPassed
range-count-before-coalescing fixture 5acceptacceptPassed

SHA-256 / 1772ca2d882d91d24a712f7dc054969854560ada49117ed80736021f9840eaa5

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(members, limit):
    return "accept" if len(members)<limit else "reject"
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('range-count-before-coalescing fixture 0', solve( ["0-1"]*(N+1),N), "reject")
check('range-count-before-coalescing fixture 1', solve(["0-1"]*N,N), "accept")
check('range-count-before-coalescing fixture 2', solve([],0), "accept")
check('range-count-before-coalescing fixture 3', solve(["0-1"],0), "reject")
check('range-count-before-coalescing fixture 4', solve(["0-1","2-3"],2), "accept")
check('range-count-before-coalescing fixture 5', solve(["0-1"],3), "accept")
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
range-count-before-coalescing fixture 0rejectrejectPassed
range-count-before-coalescing fixture 1rejectacceptFailed
range-count-before-coalescing fixture 2rejectacceptFailed
range-count-before-coalescing fixture 3rejectrejectPassed
range-count-before-coalescing fixture 4rejectacceptFailed
range-count-before-coalescing fixture 5acceptacceptPassed

SHA-256 / 5a22951064e627e715c6a5f9e88b459cbfaa94249c702c3f3aa41576487cd0ed

3 / The verified repair

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

N = 1
observations = []
def solve(members, limit):
    return "accept" if len(members)<=limit else "reject"
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('range-count-before-coalescing fixture 0', solve( ["0-1"]*(N+1),N), "reject")
check('range-count-before-coalescing fixture 1', solve(["0-1"]*N,N), "accept")
check('range-count-before-coalescing fixture 2', solve([],0), "accept")
check('range-count-before-coalescing fixture 3', solve(["0-1"],0), "reject")
check('range-count-before-coalescing fixture 4', solve(["0-1","2-3"],2), "accept")
check('range-count-before-coalescing fixture 5', solve(["0-1"],3), "accept")
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
range-count-before-coalescing fixture 0rejectrejectPassed
range-count-before-coalescing fixture 1acceptacceptPassed
range-count-before-coalescing fixture 2acceptacceptPassed
range-count-before-coalescing fixture 3rejectrejectPassed
range-count-before-coalescing fixture 4acceptacceptPassed
range-count-before-coalescing fixture 5acceptacceptPassed

SHA-256 / dc17a095d7710d86ff1488138a07b617a4411c982cdfc133fecbcbb794f068ab

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 2026-09-29T14:41:18.135838+00:00.

Case digest / e43319eb4e95b969f3bd8fa0ff90b1a35be6d151fb21704ca4fb419faf59d740