refactor(uds): Move WASM feature flagging to root Cargo.toml

Crates that don't compile for WASM are feature flagged in the root `Cargo.toml`, expcept for `libp2p-uds`. This commit removes the inconsistency.

As a side-effect, this might help prevent bugs like #3502 going forward.

Pull-Request: #3503.

Cargo.toml

@@ -108,7 +108,6 @@ libp2p-relay = { version = "0.15.0", path = "protocols/relay", optional = true }
 libp2p-rendezvous = { version = "0.12.0", path = "protocols/rendezvous", optional = true }
 libp2p-request-response = { version = "0.24.0", path = "protocols/request-response", optional = true }
 libp2p-swarm = { version = "0.42.0", path = "swarm" }
-libp2p-uds = { version = "0.38.0", path = "transports/uds", optional = true }
 libp2p-wasm-ext = { version = "0.39.0", path = "transports/wasm-ext", optional = true }
 libp2p-yamux = { version = "0.43.0", path = "muxers/yamux", optional = true }
 multiaddr = { version = "0.17.0" }
@@ -121,6 +120,7 @@ libp2p-mdns = { version = "0.43.0", path = "protocols/mdns", optional = true }
 libp2p-quic = { version = "=0.7.0-alpha.2", path = "transports/quic", optional = true }
 libp2p-tcp = { version = "0.39.0", path = "transports/tcp", optional = true }
 libp2p-tls = { version = "=0.1.0-alpha.2", path = "transports/tls", optional = true }
+libp2p-uds = { version = "0.38.0", path = "transports/uds", optional = true }
 libp2p-webrtc = { version = "=0.4.0-alpha.2", path = "transports/webrtc", optional = true }
 libp2p-websocket = { version = "0.41.0", path = "transports/websocket", optional = true }
 

src/lib.rs

@@ -119,6 +119,8 @@ pub use libp2p_tcp as tcp;
 #[doc(inline)]
 pub use libp2p_tls as tls;
 #[cfg(feature = "uds")]
+#[cfg_attr(docsrs, doc(cfg(feature = "uds")))]
+#[cfg(not(any(target_os = "emscripten", target_os = "wasi", target_os = "unknown")))]
 #[doc(inline)]
 pub use libp2p_uds as uds;
 #[cfg(feature = "wasm-ext")]

transports/uds/Cargo.toml

@@ -10,14 +10,14 @@ repository = "https://github.com/libp2p/rust-libp2p"
 keywords = ["peer-to-peer", "libp2p", "networking"]
 categories = ["network-programming", "asynchronous"]
 
-[target.'cfg(all(unix, not(target_os = "emscripten")))'.dependencies]
+[dependencies]
 async-std = { version = "1.6.2", optional = true }
 libp2p-core = { version = "0.39.0", path = "../../core" }
 log = "0.4.1"
 futures = "0.3.26"
 tokio = { version = "1.15", default-features = false, features = ["net"], optional = true }
 
-[target.'cfg(all(unix, not(target_os = "emscripten")))'.dev-dependencies]
+[dev-dependencies]
 tempfile = "3.4"
 
 # Passing arguments to the docsrs builder in order to properly document cfg's.