Nits

p2p/host/basic/basic_host.go

@@ -1013,6 +1013,8 @@ var wtComponent = ma.StringCast("/webtransport")
 func inferWebtransportAddrsFromQuic(in []ma.Multiaddr) []ma.Multiaddr {
 	// We need to check if we are listening on the same ip+port for QUIC and WebTransport.
 	// If not, there's nothing to do since we can't infer anything.
+
+	// Count the number of QUIC addrs, this will let us allocate just once at the beginning.
 	quicAddrCount := 0
 	for _, addr := range in {
 		if _, lastComponent := ma.SplitLast(addr); lastComponent.Protocol().Code == ma.P_QUIC_V1 {

p2p/host/basic/basic_host_test.go

@@ -884,7 +884,7 @@ func TestInferWebtransportAddrsFromQuic(t *testing.T) {
 				min = append(min, ma.StringCast(addr))
 			}
 			outMa := inferWebtransportAddrsFromQuic(min)
-			outStr := make([]string, 0, len(tc.out))
+			outStr := make([]string, 0, len(outMa))
 			for _, addr := range outMa {
 				outStr = append(outStr, addr.String())
 			}