FAILURE MAP
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FA-26636 / HTTP ranges / Open access

A transport reset cannot leave queued range bytes available for transmission · case 01

A transport reset cannot leave queued range bytes available for transmission.

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

ROOT CAUSE

The stream-reset-discards-queued-data decision uses return [queue,0] if reset else [queue,credit].

VERIFIED REPAIR

Apply the bounded decision exactly: return [[],0] if reset else [queue,credit]

Unsuccessful approach: The partial repair uses return [[],credit] if reset else [queue,credit], which still violates the stated contract.

Case contract

Reset returns [empty-queue,zero-credit]; normal operation preserves both.

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(reset, queue, credit):
    return [queue,0] if reset else [queue,credit]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('stream-reset-discards-queued-data fixture 0', solve(True,["x"*N],N), [[],0])
check('stream-reset-discards-queued-data fixture 1', solve(True,[],N), [[],0])
check('stream-reset-discards-queued-data fixture 2', solve(True,["x"],0), [[],0])
check('stream-reset-discards-queued-data fixture 3', solve(False,["x"*N],N), [["x"*N],N])
check('stream-reset-discards-queued-data fixture 4', solve(False,[],0), [[],0])
check('stream-reset-discards-queued-data fixture 5', solve(False,[],N), [[],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 fixtureActualExpectedOutcome
stream-reset-discards-queued-data fixture 0[['x'], 0][[], 0]Failed
stream-reset-discards-queued-data fixture 1[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 2[['x'], 0][[], 0]Failed
stream-reset-discards-queued-data fixture 3[['x'], 1][['x'], 1]Passed
stream-reset-discards-queued-data fixture 4[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 5[[], 1][[], 1]Passed

SHA-256 / ef430d57ab5fc31101fb40b625944d2430511766eda8de4e3ab5d295ff0a7cd4

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(reset, queue, credit):
    return [[],credit] if reset else [queue,credit]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('stream-reset-discards-queued-data fixture 0', solve(True,["x"*N],N), [[],0])
check('stream-reset-discards-queued-data fixture 1', solve(True,[],N), [[],0])
check('stream-reset-discards-queued-data fixture 2', solve(True,["x"],0), [[],0])
check('stream-reset-discards-queued-data fixture 3', solve(False,["x"*N],N), [["x"*N],N])
check('stream-reset-discards-queued-data fixture 4', solve(False,[],0), [[],0])
check('stream-reset-discards-queued-data fixture 5', solve(False,[],N), [[],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 fixtureActualExpectedOutcome
stream-reset-discards-queued-data fixture 0[[], 1][[], 0]Failed
stream-reset-discards-queued-data fixture 1[[], 1][[], 0]Failed
stream-reset-discards-queued-data fixture 2[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 3[['x'], 1][['x'], 1]Passed
stream-reset-discards-queued-data fixture 4[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 5[[], 1][[], 1]Passed

SHA-256 / 60d334932a5a166464b20b4ed8ee6e786b7b2c25642908c8f036d4f7e80fe2d6

3 / The verified repair

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

N = 1
observations = []
def solve(reset, queue, credit):
    return [[],0] if reset else [queue,credit]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('stream-reset-discards-queued-data fixture 0', solve(True,["x"*N],N), [[],0])
check('stream-reset-discards-queued-data fixture 1', solve(True,[],N), [[],0])
check('stream-reset-discards-queued-data fixture 2', solve(True,["x"],0), [[],0])
check('stream-reset-discards-queued-data fixture 3', solve(False,["x"*N],N), [["x"*N],N])
check('stream-reset-discards-queued-data fixture 4', solve(False,[],0), [[],0])
check('stream-reset-discards-queued-data fixture 5', solve(False,[],N), [[],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 fixtureActualExpectedOutcome
stream-reset-discards-queued-data fixture 0[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 1[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 2[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 3[['x'], 1][['x'], 1]Passed
stream-reset-discards-queued-data fixture 4[[], 0][[], 0]Passed
stream-reset-discards-queued-data fixture 5[[], 1][[], 1]Passed

SHA-256 / 3b963bea9380765ce83a26ad6e9912797fa8282392d77cdd06e7c8e5f0659652

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 2026-09-29T14:41:17.711206+00:00.

Case digest / 3304e57c40c0daee48a443b49e5b2b80d780a3cb3e0bd865240235a77f54a30c