[JarryShaw]

• Searched for similar pull requests (fix(ipv4): rebuild option areas, route slots, timestamps and reserved bits byte-exactly #1344 touches the IPv4 QS option, not these enums)
• Followed the coding style: ran pylint and isort --check on the touched files, not make mypy. pylint reports only the existing duplicate-code between the two templates, plus missing method docstrings and _dest_path access in the new test, which follows the house test style.
• make test passes, and a test case covers the change (only the modules listed below)
• Changelog entry — N/A, added centrally

What is the purpose of your pull request?

• fix — corrects a defect

---

Description of your pull request and other information

Closes #1350

RFC 4782 §3.1 gives Quick-Start "a four-bit Function field". The vendor templates set FLAG to 0 <= value <= 8. This PR widens it to 0 <= value <= 15, the decimal form that hip/hit_suite, hip/di and mh/dsmip6_tls_packet already use, and regenerates both const files. Both templates read the local DATA dict (LINK is None), so I rendered them offline by running the vendor class. The unchanged templates reproduce main's const files with no diff, and the fixed ones produce exactly the 2-line diff here.

• Before: QSFunction(9) and QSFunction(15) raise ValueError in both IPv4 and IPv6.
• After: they return <QSFunction.Unassigned: 9> and <QSFunction.Unassigned: 15>, and QSFunction(16) still raises ValueError.
• Still failing: the issue's HOPOPT repro now gets past the enum and fails at the selector with FieldValueError: invalid QS function: 15. That failure is fix(ipv6-opts): an unassigned Quick-Start function code fails the whole header #1237/fix(ipv4): an unassigned Quick-Start function code fails the whole header #1322, and this PR leaves it alone.

Tests:

• New tests/const/test_const_qs_function_range_unit.py: 0–15 resolve, -1, 16 and 255 raise, and each const file is byte-identical to its template's rendered output.
• Without the fix (the origin/main sources written over the four files), it fails 14 subtests (9–15 × 2) and passes 3 tests; with the fix, 3 passed and 40 subtests passed.
• util/run_unittest_leg.py const: 487 tests, 0 failures, 0 errors.
• tests/project: 389 passed, 1 skipped.
• Also green: test_quick_start_func_unit, test_ipv4_unit, test_ipv6_extension_unit, test_option_roundtrip_unit, test_const_enum_no_mint, test_tcp_quick_start_response_unit and test_const_enum_get.

[JarryShaw]

Cross-review verdict on 0a61b1021: GOOD TO GO (Sonnet reviewed; author Opus).

• RFC 4782 §3.1: "The third byte includes a four-bit Function field". Only 0000 and 1000 are assigned, so 0–15 is the full wire range.
• Both namespaces: 1, 9 and 15 return Unassigned. 0 and 8 are unchanged. 16 and −1 still raise through both QSFunction() and .get.
• Rendering: the PR's templates render byte-identical (cmp) to its const files. The unchanged main templates reproduce main's const files, which validates the method. hip/hit_suite, hip/di and mh/dsmip6_tls_packet use the same 0 <= value <= 15 form.
• Callers: every caller goes through Enum_QSFunction.get, and none uses except ValueError as a validity check. HOPOPT function 15 now gets past the enum and stops at the selector with FieldValueError. That part is fix(ipv4): an unassigned Quick-Start function code fails the whole header #1322, which the PR rightly does not close.
• Tests: the revert proof gives 14 errors on main's sources. The const leg runs 487 tests with 0 failures, and test_ipv4_unit plus test_ipv6_extension_unit run 87, OK.

[github-actions]

Coverage: 88.96% (unit tier, Python 3.14, 0a61b1021, Unit Tests run success)

Package	Statements	Missed	Branches	Partial	Cover
pcapkit (top level)	104	4	20	4	93.55%
pcapkit/const	18777	1033	2348	844	90.26%
pcapkit/corekit	1878	89	580	22	94.43%
pcapkit/dumpkit	189	1	68	1	99.22%
pcapkit/foundation	2442	102	852	39	94.38%
pcapkit/interface	112	7	40	5	92.11%
pcapkit/protocols	15968	206	4158	177	98.06%
pcapkit/toolkit	495	73	150	1	83.57%
pcapkit/utilities	429	4	122	4	98.55%
pcapkit/vendor	4409	2342	1006	157	43.25%

Per-file detail: the coverage-html artifact of this run.

[JarryShaw]

The red PyPCAP/PyPCAPFile parity Python 3.11 leg is not caused by this diff. It is a slow mirror hitting a bound that main has already widened.

• Both apt attempts in job 113001716708 were killed after exactly 90 s (20:53:30→20:55:00 and 20:55:04→20:56:34). Each stalled on the Azure mirror, the second while fetching libwireshark17t64, a 23.7 MB package.
• 0a61b1021 predates ci(unit-tests): widen the apt bounds so a slow mirror still installs tshark #1309 (08c874eff), which raised that bound to 180 s. This branch still runs the old timeout 90.
• I re-ran the failed jobs, but a re-run keeps the old bound. The fix is to update the branch onto main, which the strict ruleset requires anyway. The Required checks passed failure follows from this leg.