fix(swarm-derive): allow unreachable_code on uninhabited ToSwarm fields - #6602
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Saraswat123 wants to merge 1 commit into
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fix(swarm-derive): allow unreachable_code on uninhabited ToSwarm fields#6602Saraswat123 wants to merge 1 commit into
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When a NetworkBehaviour field has a To Swarm type that's uninhabited like dummy Behaviour, whose ToSwarm = Infallible, the derive macro still generates a match arm for it in poll(). That arm can never actually run but it has to exist so the macro compiles when other fields do have real To Swarm types. Newer nightly compilers flag that dead arm as unreachable code, which fails the build for anyone compiling with D warnings.
The fix: "I Wrapped just that one generated call in #[allow(unreachable_code)]. This is the same fix the issue reporter suggested themselves nothing else in the generated code changes."
Testing, I Added a test combining a real behaviour (ping, inhabited ToSwarm) with dummy.Behaviour (uninhabited ToSwarm) through the derive macro, to prove the mixed case still compiles. Full swarm,derive test suite- 20/20 pass. cargo fmt, clippyp libp2p,swarm,derive, and clippy -p libp2p,swarm features macros all clean.