(10) feat(match-action): MatchKey trait + derive + bolero generators

[daniel-noland]

Stack (10). Base: pr/daniel-noland/fixed-size-lookup.

The match-action core: the trait + derive macro that everything keys off, plus
its property-test generators.

• feat(match-action): MatchKey trait + #[derive(MatchKey)] proc-macro.
• feat(match-action): bolero FieldHit / FieldMiss generators.

Review focus: derive semantics and generator coverage, in isolation from ACL.

Review stack (merge bottom -> top):

• (7) (7) threading rewrite #1555 threading rewrite
• (8) (8) feat(dpdk): test EAL harness (with_eal macro + const fn) #1572 dpdk test EAL harness
• (9) (9) feat: fixed-size + lookup foundation trait crates #1573 fixed-size + lookup
• (10) (10) feat(match-action): MatchKey trait + derive + bolero generators #1574 match-action
• (11) (11) feat(acl): crate scaffolding + software reference backend #1575 acl reference backend
• (12) (12) feat(acl): rte_acl backend + differential-vs-reference + benches #1576 acl rte_acl backend
• (13) (13) feat(cascade): in-memory LSM match-action store + real-shape ACL tests #1567 cascade

[Copilot]

Pull request overview

Adds the match-action core crate and derive macro, providing typed field/rule specs, erased predicates, MatchKey derivation, and bolero-based field generators for future ACL and cascade layers.

Changes:

• Introduces dataplane-match-action with MatchKey, field specs, predicates, rule specs, and generator support.
• Adds dataplane-match-action-derive proc macro for deriving key layout and companion rule structs.
• Adds workspace registration, lockfile entries, and derive/generator roundtrip tests.

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
Cargo.toml	Registers match-action crates and package metadata.
Cargo.lock	Adds lock entries for the new crates.
match-action/Cargo.toml	Defines crate dependencies and feature flags.
match-action/src/lib.rs	Exposes public match-action API types and traits.
match-action/src/field.rs	Re-exports FixedSize.
match-action/src/rule.rs	Adds rule field specs and universal checks.
match-action/src/predicate.rs	Adds erased predicate matching and conversions.
match-action/src/generator.rs	Adds bolero hit/miss generators for field predicates.
match-action/tests/derive_roundtrip.rs	Tests derive layout, packing, rules, and generics.
match-action-derive/Cargo.toml	Defines proc-macro crate dependencies/features.
match-action-derive/src/lib.rs	Implements #[derive(MatchKey)].

[mvachhar]

I love the use of the macro, I hate the definition since it is really hard to understand, but that is the nature of these macros I suppose.

Copilot has some things that should be addressed.

Also, your FiveTuple doc example should be ThreeTuple or expanded to an actual FiveTuple.

I also feel like the macro testing is light, but that might be ok if we are mainly just using a single data type for most of dataplane. We can fix bugs later as we add more data types, assuming bugs crop up.