FA-6586 / HTTP semantics / Open access

Informational and bodyless statuses suppress payload transmission · case 01

Informational and bodyless statuses suppress payload transmission.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The faulty implementation uses `'' if status == 204 else body` for the status-body decision.

VERIFIED REPAIR

Apply the explicit status-body contract, including the tested boundary and negative cases.

Unsuccessful approach: The attempted repair uses `'' if status < 300 else body` and still violates a separate fixture.

Case contract

Informational and bodyless statuses suppress payload transmission: return the result specified by the explicit input/output boundary fixtures.

Why this case matters

This deterministic http semantics model isolates the status-body policy at a network component boundary.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(status, body):
    return '' if status == 204 else body
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(101, 'x'), '')", "check('fixture 2', solve(304, 'x'), '')", "check('fixture 3', solve(200, 'x'), 'x')", "check('fixture 4', solve(404, 'e'), 'e')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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
fixture 2	`x`		Failed
fixture 3	`x`	`x`	Passed
fixture 4	`e`	`e`	Passed
fixture 1	`x`		Failed

SHA-256 / e509fd602246c0c881caf5d073b5b4b81f81ce7dfb7b1caa3fb179e51852a524

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(status, body):
    return '' if status < 300 else body
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(101, 'x'), '')", "check('fixture 2', solve(304, 'x'), '')", "check('fixture 3', solve(200, 'x'), 'x')", "check('fixture 4', solve(404, 'e'), 'e')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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
fixture 2	`x`		Failed
fixture 3		`x`	Failed
fixture 4	`e`	`e`	Passed
fixture 1			Passed

SHA-256 / 5165f79e2f2768b80d8742a6c9e17f8fb288906dcd53ecc5599f4c71824ce4cc

3 / The verified repair

Exit 0

"""Failure Map reference implementation. Python standard library only."""
import json
import ipaddress
import re
from urllib.parse import urlsplit, urljoin
N = 1
observations = []
def solve(status, body):
    return '' if 100 <= status < 200 or status in (204, 205, 304) else body
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
_fixtures = ["check('fixture 1', solve(101, 'x'), '')", "check('fixture 2', solve(304, 'x'), '')", "check('fixture 3', solve(200, 'x'), 'x')", "check('fixture 4', solve(404, 'e'), 'e')"]
for _line in _fixtures[N % len(_fixtures):] + _fixtures[:N % len(_fixtures)]:
    exec(_line)
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
fixture 2			Passed
fixture 3	`x`	`x`	Passed
fixture 4	`e`	`e`	Passed
fixture 1			Passed

SHA-256 / b16a2834398a01694036fe2e91d53075c0b3fedd48fc7ffe48b9ee71e0f37703

Verification & scope

Bounded deterministic policy model over validated inputs; not a complete protocol stack or an interoperability claim. The five variants rotate the same explicit fixture set. 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 2026-09-29T14:38:03.431394+00:00.

Case digest / f3fad3d6fa6a21d0dfefc3de4aa9e685b9720891314531b0a2341428d809e48d