Before 8bf01b7ad, nested rule-set evaluation reused the parent rule
match cache. In practice, this meant these fields leaked across nested
evaluation:
- SourceAddressMatch
- SourcePortMatch
- DestinationAddressMatch
- DestinationPortMatch
- DidMatch
That leak had two opposite effects.
First, it made included rule-sets partially behave like the docs'
"merged" semantics. For example, if an outer route rule had:
rule_set = ["geosite-additional-!cn"]
ip_cidr = 104.26.10.0/24
and the inline rule-set matched `domain_suffix = speedtest.net`, the
inner match could set `DestinationAddressMatch = true` and the outer
rule would then pass its destination-address group check. This is why
some `rule_set + ip_cidr` combinations used to work.
But the same leak also polluted sibling rules and sibling rule-sets.
A branch could partially match one group, then fail later, and still
leave that group cache set for the next branch. This broke cases such
as gh-3485: with `rule_set = [test1, test2]`, `test1` could touch
destination-address cache before an AdGuard `@@` exclusion made the
whole branch fail, and `test2` would then run against dirty state.
8bf01b7ad fixed that by cloning metadata for nested rule-set/rule
evaluation and resetting the rule match cache for each branch. That
stopped sibling pollution, but it also removed the only mechanism by
which a successful nested branch could affect the parent rule's grouped
matching state.
As a result, nested rule-sets became pure boolean sub-items against the
outer rule. The previous example stopped working: the inner
`domain_suffix = speedtest.net` still matched, but the outer rule no
longer observed any destination-address-group success, so it fell
through to `final`.
This change makes the semantics explicit instead of relying on cache
side effects:
- `rule_set: ["a", "b"]` is OR
- rules inside one rule-set are OR
- each nested branch is evaluated in isolation
- failed branches contribute no grouped match state
- a successful branch contributes its grouped match state back to the
parent rule
- grouped state from different rule-sets must not be combined together
to satisfy one outer rule
In other words, rule-sets now behave as "OR branches whose successful
group matches merge into the outer rule", which matches the documented
intent without reintroducing cross-branch cache leakage.
