test: add TestDial test

Signed-off-by: Dwi Siswanto <[email protected]>

Author: dwisiswant0

fastdialer/dialer_private_test.go

@@ -1,9 +1,13 @@
 package fastdialer
 
 import (
+	"context"
+	"net"
 	"sync/atomic"
 	"testing"
 	"time"
+
+	ztls "github.com/zmap/zcrypto/tls"
 )
 
 type mockCloser struct {
@@ -85,3 +89,84 @@ func TestCloseAfterTimeout_ExternalCancelPreemptsTimeout(t *testing.T) {
 		t.Fatalf("expected zero close calls at end of test, got %d", got)
 	}
 }
+
+func TestDial(t *testing.T) {
+	t.Run("ZTLSWithConfig", func(t *testing.T) {
+		listener, err := net.Listen("tcp", "127.0.0.1:0")
+		if err != nil {
+			t.Fatalf("Failed to start listener: %v", err)
+		}
+		defer listener.Close()
+
+		serverAddr := listener.Addr().String()
+
+		go func() {
+			for {
+				conn, err := listener.Accept()
+				if err != nil {
+					return
+				}
+
+				// hold conn w/o completing handshake
+				time.Sleep(5 * time.Second)
+				conn.Close()
+			}
+		}()
+
+		options := DefaultOptions
+		options.DialerTimeout = 100 * time.Millisecond
+
+		dialer, err := NewDialer(options)
+		if err != nil {
+			t.Fatalf("Failed to create dialer: %v", err)
+		}
+		defer dialer.Close()
+
+		ztlsConfig := &ztls.Config{
+			InsecureSkipVerify: true,
+			ServerName:         "localhost",
+		}
+
+		_, err = dialer.DialZTLSWithConfig(context.Background(), "tcp", serverAddr, ztlsConfig)
+		if err == nil {
+			t.Fatal("Expected an error due to timeout, got nil")
+		}
+	})
+
+	t.Run("TLSWithConfigFallback", func(t *testing.T) {
+		listener, err := net.Listen("tcp", "127.0.0.1:0")
+		if err != nil {
+			t.Fatalf("Failed to start listener: %v", err)
+		}
+		defer listener.Close()
+
+		serverAddr := listener.Addr().String()
+
+		go func() {
+			for {
+				conn, err := listener.Accept()
+				if err != nil {
+					return
+				}
+				time.Sleep(5 * time.Second)
+				conn.Close()
+			}
+		}()
+
+		options := DefaultOptions
+		options.DialerTimeout = 100 * time.Millisecond
+		options.DisableZtlsFallback = false
+
+		dialer, err := NewDialer(options)
+		if err != nil {
+			t.Fatalf("Failed to create dialer: %v", err)
+		}
+		defer dialer.Close()
+
+		_, err = dialer.DialTLSWithConfig(context.Background(), "tcp", serverAddr, DefaultTLSConfig)
+
+		if err == nil {
+			t.Fatal("Expected an error due to timeout, got nil")
+		}
+	})
+}