[JarryShaw]

• Searched for similar pull requests

• Followed the coding style (make pylint, make mypy, make isort) — run on the 6 touched files: isort and mypy clean; pylint differs from base only by one unused-argument per schema, from the TYPE_CHECKING __init__ stub

• make test passes, and a test case covers the change — the modules listed below only

• Added a changelog entry — N/A, added centrally

• fix — corrects a defect

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Closes #1199. HOPOPT and IPv6-Opts, types 0x23 and 0x63: the schema now maps the reserved flag bits and reads sub_tlvs (Opt Data Len − 4). The data classes gain RPLFlags.reserved and RPLOption.sub_tlvs. The reader accepts any length ≥ 4. _make_opt_rpl takes reserved=0 and sub_tlvs=b'', so its defaults are unchanged.

input	before	after
3b00230401020000	rebuilds 3b00230400020000	rebuilds unchanged
3b0123060102000000aa000000000000	ProtocolError: [OptNo 35] invalid format	parses, sub_tlvs=b'\x00\xaa'
3b00230001020000 (len 0)	ProtocolError	ProtocolError

Constructor change: both data classes have a new required field. The one existing test that built them without it (test_ipv6_extension_unit.py) now passes reserved=0, sub_tlvs=b''.

Tests: new test_rpl_option_reserved_subtlv_unit.py: 5 passed, 42 subtests. With the fix reverted: 32 failed. test_rpl_option_unit 3 passed; test_ipv6_extension_unit 61 passed; test_option_roundtrip_unit 6 passed; tests/project 389 passed, 1 skipped; run_unittest_leg.py protocols/internet 503 tests, 0 failures.

[JarryShaw]

Cross-review verdict on b90b10cb7: GOOD TO GO (Sonnet; author Opus).

• Fixed and checked: 3b00230401020000 now rebuilds unchanged, and 3b0123060102000000aa000000000000 parses with sub_tlvs=b'\x00\xaa' and rebuilds those RPL octets exactly. Both hold for 0x23 and 0x63, in both classes. Lengths below 4 still raise ProtocolError. 0–251 sub-TLV octets round-trip, and 252 is rejected.
• RFC 6553 §3: the flags are O|R|F|0|0|0|0|0, so the reserved field is 5 bits wide. Opt Data Len is at most 255, which leaves 251 octets for sub-TLVs.
• Tests: the new module fails 32 of 37 cases on the base commit. run_unittest_leg.py protocols/internet: 503 tests, 0 failures.
• Fixtures: 1579 frames are unchanged. None of them contains an RPL option, so this shows no collateral change, not coverage of the fix.
• Breaking: RPLFlags and RPLOption gain required fields. Every caller in pcapkit/ and tests/ is updated or unaffected.
• Nit: no test exercises the 251-octet success boundary.
• Out of scope: Pad1 runs are regenerated as minimal padding on rebuild (ipv6_opts.py:1342-1387, hopopt.py:1353-1397). This also happens on main without any RPL option, and it will be filed separately.

[github-actions]

Coverage: 88.91% (unit tier, Python 3.14, b90b10cb7, Unit Tests run success)

Package	Statements	Missed	Branches	Partial	Cover
pcapkit (top level)	104	4	20	4	93.55%
pcapkit/const	18757	1034	2342	845	90.24%
pcapkit/corekit	1878	91	580	22	94.34%
pcapkit/dumpkit	142	0	42	0	100.00%
pcapkit/foundation	2442	102	852	39	94.38%
pcapkit/interface	112	7	40	5	92.11%
pcapkit/protocols	15777	190	4036	165	98.18%
pcapkit/toolkit	487	65	144	1	85.42%
pcapkit/utilities	429	4	122	4	98.55%
pcapkit/vendor	4409	2359	1006	158	42.84%

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