minor fixes from review

p2p/addrbook.go

@@ -191,7 +191,12 @@ func (a *AddrBook) size() int {
 	return a.nNew + a.nOld
 }
 
-// PickAddress picks an address to connect to with new/old bias.
+// PickAddress picks an address to connect to.
+// The address is picked randomly from an old or new bucket according
+// to the newBias argument, which must be between [0, 100] (or else is truncated to that range)
+// and determines how biased we are to pick an address from a new bucket.
+// PickAddress returns nil if the AddrBook is empty or if we try to pick
+// from an empty bucket.
 func (a *AddrBook) PickAddress(newBias int) *NetAddress {
 	a.mtx.Lock()
 	defer a.mtx.Unlock()

p2p/addrbook_test.go

@@ -112,6 +112,7 @@ func TestAddrBookLookup(t *testing.T) {
 }
 
 func TestAddrBookPromoteToOld(t *testing.T) {
+	assert := assert.New(t)
 	fname := createTempFileName("addrbook_test")
 
 	randAddrs := randNetAddressPairs(t, 100)
@@ -143,9 +144,7 @@ func TestAddrBookPromoteToOld(t *testing.T) {
 		t.Errorf("selection could not be bigger than the book")
 	}
 
-	if book.Size() != 100 {
-		t.Errorf("Size is not 100. Got %v", book.Size())
-	}
+	assert.Equal(book.Size(), 100, "expecting book size to be 100")
 }
 
 func TestAddrBookHandlesDuplicates(t *testing.T) {

p2p/pex_reactor.go

@@ -252,10 +252,13 @@ func (r *PEXReactor) ensurePeers() {
 		if try == nil {
 			continue
 		}
-		_, alreadySelected := toDial[try.IP.String()]
-		alreadyDialing := r.Switch.IsDialing(try)
-		alreadyConnected := r.Switch.Peers().Has(try.IP.String())
-		if alreadySelected || alreadyDialing || alreadyConnected {
+		if _, selected := toDial[try.IP.String()]; selected {
+			continue
+		}
+		if dialling := r.Switch.IsDialing(try); dialling {
+			continue
+		}
+		if connected := r.Switch.Peers().Has(try.IP.String()); connected {
 			continue
 		}
 		r.Logger.Info("Will dial address", "addr", try)