fix: forward sent messages to the tracer

options.go

@@ -74,6 +74,15 @@ func WithTracer(tap tracer.Tracer) Option {
 	return Option{
 		func(bs *Bitswap) {
 			bs.tracer = tap
+			// the tests use this to hot update tracers, we need to update tracers of impls if we are running
+			if bs.Client != nil {
+				if tap != nil {
+					tap = nopReceiveTracer{tap}
+				}
+				client.WithTracer(tap)(bs.Client)
+				// no need to check for server as they can't not be both running
+				server.WithTracer(tap)(bs.Server)
+			}
 		},
 	}
 }

polyfill.go

@@ -75,6 +75,12 @@ func New(ctx context.Context, net network.BitSwapNetwork, bstore blockstore.Bloc
 		}
 	}
 
+	if bs.tracer != nil {
+		var tracer tracer.Tracer = nopReceiveTracer{bs.tracer}
+		clientOptions = append(clientOptions, client.WithTracer(tracer))
+		serverOptions = append(serverOptions, server.WithTracer(tracer))
+	}
+
 	stats := metrics.New(ctx)
 	bs.Server = server.New(ctx, net, bstore, stats, serverOptions...)
 	bs.Client = client.New(ctx, net, bstore, stats, append(clientOptions, client.WithBlockReceivedNotifier(bs.Server))...)

sendOnlyTracer.go

@@ -0,0 +1,20 @@
+package bitswap
+
+import (
+	"github.com/ipfs/go-bitswap/message"
+	"github.com/ipfs/go-bitswap/tracer"
+	"github.com/libp2p/go-libp2p-core/peer"
+)
+
+type sendOnlyTracer interface {
+	MessageSent(peer.ID, message.BitSwapMessage)
+}
+
+var _ tracer.Tracer = nopReceiveTracer{}
+
+// we need to only trace sends because we already trace receives in the polyfill object (to not get them traced twice)
+type nopReceiveTracer struct {
+	sendOnlyTracer
+}
+
+func (nopReceiveTracer) MessageReceived(peer.ID, message.BitSwapMessage) {}