add test covering a recently fixed regression in initial PEX

diff --git a/pex_test.go b/pex_test.go
index e002362717110360fbb14f4cb895a3fe7a48d345..a59c8ee4e970ee3d34f6c845f2267de1130724fa 100644 (file)
--- a/pex_test.go
+++ b/pex_test.go
@@ -288,6 +288,38 @@ func TestPexGenmsg(t *testing.T) {
        }
 }
 
+// generate 𝑛 distinct values of net.Addr
+func addrgen(n int) chan net.Addr {
+       c := make(chan net.Addr)
+       go func() {
+               for i := 4747; i < 65535 && n > 0; i++ {
+                       c <- &net.TCPAddr{IP: net.IPv4(127, 0, 0, 1), Port: i}
+                       n--
+               }
+               close(c)
+       }()
+       return c
+}
+
+func TestPexInitialNoCutoff(t *testing.T) {
+       const n = 2 * pexMaxDelta
+       var s pexState
+
+       c := addrgen(n)
+       for addr := range c {
+               s.Add(&PeerConn{peer: peer{RemoteAddr: addr}})
+       }
+       m, seq := s.Genmsg(0)
+
+       require.EqualValues(t, n, seq)
+       require.EqualValues(t, n, len(m.Added))
+       require.EqualValues(t, n, len(m.AddedFlags))
+       require.EqualValues(t, 0, len(m.Added6))
+       require.EqualValues(t, 0, len(m.Added6Flags))
+       require.EqualValues(t, 0, len(m.Dropped))
+       require.EqualValues(t, 0, len(m.Dropped6))
+}
+
 func TestPexAdd(t *testing.T) {
        addrs4 := []krpc.NodeAddr{
                krpc.NodeAddr{IP: net.IPv4(127, 0, 0, 1), Port: 4747}, // 0