Added parser for $to option in NetworkFilter.

[boocmp]

Added support for parsing the $to option in network filters. Matching behavior remains unchanged.

[github-actions]

[puLL-Merge] - brave/adblock-rust@701

Description

Adds parsing/storage for $to= network filter option (destination hostname restrictions). Refactors domain-parsing logic into shared helpers parse_pipe_delimited_domains and hash_pipe_delimited_domains. Adds new flatbuffer fields opt_to_domains/opt_to_not_domains, bumps DAT version 5→6. Regenerates flatbuffer code from newer compiler (::flatbuffers → flatbuffers, alloc:: → std). $to filters are parsed and stored only — not applied at match time (skipped in add_filter via has_to_option()).

Possible Issues

• $to silently ignored at match time. NetworkRulesBuilder::add returns early on has_to_option(), dropping rule entirely. Filters with $to provide no filtering. Match tests confirm this (all matches_test assert false). If a rule uses only $to as a restriction on an otherwise-blocking rule, this weakens blocking vs. dropping the rule. Verify intent — could under-block. Comment says "for now," so presumably staged rollout.

• DAT version bump correct but consumers with v5 caches must regenerate. Expected.

• Regex-domain filter behavior: parse_pipe_delimited_domains drops /regex/ entries silently, errors only if all dropped (NoSupportedDomains). Matches existing domain= behavior. Consistent.

• compute_filter_id now includes $to hashes — changes filter IDs for existing rules? No, only rules with $to set contribute new hasher writes; existing rules unaffected since opt_to_* are None. Test hash changes reflect the format version bump, not ID collisions.

Changes

src/data_format/mod.rs

• Version 5→6.

src/filters/abstract_network.rs

• Extract parse_pipe_delimited_domains helper. Add NetworkFilterOption::To. Parse to option. Wire unit test module.

src/filters/network.rs

• Add opt_to_domains/opt_to_not_domains fields. Extract hash_pipe_delimited_domains (deduped shared logic). Handle To option. Add has_to_option(). Include $to hashes in compute_filter_id (+#[allow(clippy::too_many_arguments)]).

src/filters/fb_network_builder.rs

• Serialize new fields. Early-return in add for $to filters.

src/flatbuffers/fb_network_filter.fbs + generated.rs

• New opt_to_domains/opt_to_not_domains fields. Full regeneration with new flatbuffer compiler output style (unrelated churn: ::flatbuffers→flatbuffers, alloc::→std types, unsafe fn→outer unsafe {} blocks).

tests/unit/

• New abstract_network.rs helper tests. parses_to parse tests. Match tests asserting $to ignored. Updated hash constants + filter count (122996→123328).

Notes

• Generated-file churn (.fbs regen) mixed with feature work makes review harder. Consider separating compiler-upgrade regen from feature commit in future.
• Filter count delta (+332) suggests some $to rules previously rejected now parse. Confirm expected.

sequenceDiagram
    participant Src as filter line "$to=..."
    participant AN as abstract_network::parse_filter_options
    participant NF as NetworkFilter::parse
    participant FB as NetworkRulesBuilder::add
    participant Flat as fb_network_builder

    Src->>AN: parse options
    AN->>AN: parse_pipe_delimited_domains(value)
    AN-->>NF: NetworkFilterOption::To(domains)
    NF->>NF: hash_pipe_delimited_domains -> opt_to_domains / opt_to_not_domains
    NF-->>FB: NetworkFilter{ opt_to_* set }
    FB->>FB: has_to_option()?
    alt has $to
        FB-->>FB: early return (not indexed for matching)
    else no $to
        FB->>Flat: serialize + index
    end
    FB->>Flat: serialize opt_to_* fields (storage only)

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[Copilot]

Pull request overview

This PR adds parsing and serialization support for the $to= option in network filters, while aiming to keep runtime matching behavior unchanged by not applying $to constraints during request evaluation.

Changes:

• Added $to= parsing (pipe-delimited domain list with ~ negation) and stored the parsed data on NetworkFilter.
• Extended the FlatBuffers schema/data format to persist $to domain restrictions and bumped ADBLOCK_RUST_DAT_VERSION.
• Added/updated unit tests and adjusted engine serialization hash expectations to reflect the new data format.

Reviewed changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/unit/filters/network.rs	Adds unit tests asserting $to= is parsed into opt_to_domains / opt_to_not_domains.
tests/unit/filters/network_matchers.rs	Adds tests asserting $to-containing filters do not affect matching behavior.
tests/unit/filters/abstract_network.rs	New unit tests for pipe-delimited domain parsing helper.
tests/unit/engine.rs	Updates expected serialization hashes and network filter counts for the new format.
src/flatbuffers/fb_network_filter.fbs	Adds opt_to_domains / opt_to_not_domains fields to the NetworkFilter FlatBuffer table.
src/flatbuffers/fb_network_filter_generated.rs	Regenerates FlatBuffers bindings to include the new fields and other generator output changes.
src/filters/network.rs	Stores $to domain restrictions on NetworkFilter, wires parsing, and includes them in filter ID computation.
src/filters/fb_network_builder.rs	Serializes $to domain restrictions, and currently skips inserting $to filters into the engine.
src/filters/abstract_network.rs	Introduces parse_pipe_delimited_domains and uses it for domain/from and new to options; wires unit tests.
src/data_format/mod.rs	Bumps the persisted data format version from 5 to 6.

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[github-actions]

Rust Benchmark

Details

Benchmark suite	Current: 3f916d7	Previous: bd2f117	Ratio
rule-match-browserlike/brave-list	2242670735 ns/iter (± 17711909)	2381054868 ns/iter (± 34045922)	0.94
rule-match-first-request/brave-list	1363603 ns/iter (± 89562)	1472017 ns/iter (± 27538)	0.93
blocker_new/brave-list	114674686 ns/iter (± 2148085)	116855936 ns/iter (± 843156)	0.98
blocker_new/brave-list-deserialize	31095429 ns/iter (± 105372)	33093630 ns/iter (± 1471291)	0.94
memory-usage-final/brave-list-initial	9560898 B/iter (± 0)	9560762 B/iter (± 0)	1.00
memory-usage-final/brave-list-1000-requests	3157476 B/iter (± 0)	3157476 B/iter (± 0)	1
memory-usage-max/brave-list-initial/max	32069586 B/iter (± 0)	32069450 B/iter (± 0)	1.00
memory-usage-alloc-count/brave-list-initial/alloc-count	284056 allocs/iter (± 0)	282954 allocs/iter (± 0)	1.00
memory-usage-alloc-count/brave-list-1000-requests/alloc-count	80015 allocs/iter (± 0)	80015 allocs/iter (± 0)	1
url_cosmetic_resources/brave-list	184637 ns/iter (± 1941)	185445 ns/iter (± 1200)	1.00
cosmetic-class-id-match/brave-list	3219801 ns/iter (± 840237)	3228305 ns/iter (± 800958)	1.00

This comment was automatically generated by workflow using github-action-benchmark.