1 files changed, 46 insertions, 0 deletions
diff --git a/p2p/enode/localnode_test.go b/p2p/enode/localnode_test.go
index f5e3496d6..00746a8d2 100644
--- a/p2p/enode/localnode_test.go
+++ b/p2p/enode/localnode_test.go
@@ -17,10 +17,13 @@
 package enode
 
 import (
+	"math/rand"
+	"net"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/p2p/enr"
+	"github.com/stretchr/testify/assert"
 )
 
 func newLocalNodeForTesting() (*LocalNode, *DB) {
@@ -74,3 +77,46 @@ func TestLocalNodeSeqPersist(t *testing.T) {
 		t.Fatalf("wrong seq %d on instance with changed key, want 1", s)
 	}
 }
+
+// This test checks behavior of the endpoint predictor.
+func TestLocalNodeEndpoint(t *testing.T) {
+	var (
+		fallback  = &net.UDPAddr{IP: net.IP{127, 0, 0, 1}, Port: 80}
+		predicted = &net.UDPAddr{IP: net.IP{127, 0, 1, 2}, Port: 81}
+		staticIP  = net.IP{127, 0, 1, 2}
+	)
+	ln, db := newLocalNodeForTesting()
+	defer db.Close()
+
+	// Nothing is set initially.
+	assert.Equal(t, net.IP(nil), ln.Node().IP())
+	assert.Equal(t, 0, ln.Node().UDP())
+	assert.Equal(t, uint64(1), ln.Node().Seq())
+
+	// Set up fallback address.
+	ln.SetFallbackIP(fallback.IP)
+	ln.SetFallbackUDP(fallback.Port)
+	assert.Equal(t, fallback.IP, ln.Node().IP())
+	assert.Equal(t, fallback.Port, ln.Node().UDP())
+	assert.Equal(t, uint64(2), ln.Node().Seq())
+
+	// Add endpoint statements from random hosts.
+	for i := 0; i < iptrackMinStatements; i++ {
+		assert.Equal(t, fallback.IP, ln.Node().IP())
+		assert.Equal(t, fallback.Port, ln.Node().UDP())
+		assert.Equal(t, uint64(2), ln.Node().Seq())
+
+		from := &net.UDPAddr{IP: make(net.IP, 4), Port: 90}
+		rand.Read(from.IP)
+		ln.UDPEndpointStatement(from, predicted)
+	}
+	assert.Equal(t, predicted.IP, ln.Node().IP())
+	assert.Equal(t, predicted.Port, ln.Node().UDP())
+	assert.Equal(t, uint64(3), ln.Node().Seq())
+
+	// Static IP overrides prediction.
+	ln.SetStaticIP(staticIP)
+	assert.Equal(t, staticIP, ln.Node().IP())
+	assert.Equal(t, fallback.Port, ln.Node().UDP())
+	assert.Equal(t, uint64(4), ln.Node().Seq())
+}