fix: Add grpc tester receiver to TestDial

Author: aranjans

credentials/alts/internal/handshaker/service/service_test.go

@@ -20,21 +20,35 @@ package service
 
 import (
 	"testing"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/internal/grpctest"
 )
 
+type s struct {
+	grpctest.Tester
+}
+
+func Test(t *testing.T) {
+	grpctest.RunSubTests(t, s{})
+}
+
 const (
 	testAddress1 = "some_address_1"
 	testAddress2 = "some_address_2"
 )
 
-// TestDial verifies the behavior of the Dial function in managing gRPC connections
-// and checks the below scenarios:
-//   - First call to Dial with an address creates a new connection and stores it.
-//   - Second call to Dial with the same address returns the existing connection
-//     and expects the returned connection matching with ƒirst connection.
-//   - Third call to Dial with a different address creates a separate new connection
-//     and expects a different connection from connnection1 and connection2.
-func TestDial(t *testing.T) {
+// TestDial verifies the behaviour of alts handshake when there are multiple Dials.
+// If a connection has already been established, this function returns it.
+// Otherwise, a new connection is created.
+func (s) TestDial(t *testing.T) {
+	temp := hsDialer
+	hsDialer = func(target string, opts ...grpc.DialOption) (*grpc.ClientConn, error) {
+		return &grpc.ClientConn{}, nil
+	}
+	defer func() {
+		hsDialer = temp
+	}()
 	// First call to Dial, it should create a connection to the server running
 	// at the given address.
 	conn1, err := Dial(testAddress1)
@@ -60,8 +74,7 @@ func TestDial(t *testing.T) {
 		t.Fatalf("hsConnMap[%v]=%v, want %v", testAddress1, got, want)
 	}
 
-	// Third call to Dial using a different address should create a new
-	// connection.
+	// Third call to Dial using a different address should create a new connection.
 	conn3, err := Dial(testAddress2)
 	if err != nil {
 		t.Fatalf("third call to Dial(%v) failed: %v", testAddress2, err)