Improve code comments

client.go

@@ -1066,6 +1066,7 @@ func (cl *Client) gotMetadataExtensionMsg(payload []byte, t *Torrent, c *connect
 	}
 }
 
+// Also handles choking and unchoking of the remote peer.
 func (cl *Client) upload(t *Torrent, c *connection) {
 	if cl.config.NoUpload {
 		return
@@ -1075,10 +1076,14 @@ func (cl *Client) upload(t *Torrent, c *connection) {
 	}
 	seeding := t.seeding()
 	if !seeding && !t.connHasWantedPieces(c) {
+		// There's no reason to upload to this peer.
 		return
 	}
+	// Breaking or completing this loop means we don't want to upload to the
+	// peer anymore, and we choke them.
 another:
 	for seeding || c.chunksSent < c.UsefulChunksReceived+6 {
+		// We want to upload to the peer.
 		c.Unchoke()
 		for r := range c.PeerRequests {
 			err := cl.sendChunk(t, c, r)

client_test.go

@@ -296,6 +296,7 @@ func TestClientTransferSmallCache(t *testing.T) {
 }
 
 func TestClientTransferVarious(t *testing.T) {
+	// Leecher storage
 	for _, ls := range []storageFactory{
 		NewFileCacheClientStorageFactory(FileCacheClientStorageFactoryParams{
 			Wrapper: fileCachePieceFileStorage,
@@ -305,6 +306,7 @@ func TestClientTransferVarious(t *testing.T) {
 		}),
 		storage.NewBoltDB,
 	} {
+		// Seeder storage
 		for _, ss := range []func(string) storage.ClientImpl{
 			storage.NewFile,
 			storage.NewMMap,

config.go

@@ -22,10 +22,12 @@ type Config struct {
 	NoDHT bool `long:"disable-dht"`
 	// Overrides the default DHT configuration.
 	DHTConfig dht.ServerConfig
-	// Don't ever send chunks to peers.
+
+	// Never send chunks to peers.
 	NoUpload bool `long:"no-upload"`
 	// Upload even after there's nothing in it for us. By default uploading is
-	// not altruistic.
+	// not altruistic, we'll upload slightly more than we download from each
+	// peer.
 	Seed bool `long:"seed"`
 	// User-provided Client peer ID. If not present, one is generated automatically.
 	PeerID string