[#282] client: Close connection on non-nil error in Dial

A particular status code does not imply that connection has not been
established. However, `Dial()` requires user to call `Close()` only if
the error was nil. Thus, it is `Dial()` responsibility to close
everything if it returns an error.

Introduced after the gRPC update in #270 (6009d089fc).

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

client/client.go

@@ -106,16 +106,21 @@ func (c *Client) Dial(ctx context.Context, prm PrmDial) error {
 		client.WithContext(ctx),
 	)
 	if err != nil {
+		var ctxErr error
+
 		// return context errors since they signal about dial problem
 		if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
-			return err
+			ctxErr = err
+		} else if st, ok := status.FromError(err); ok && st.Code() == codes.Canceled {
+			ctxErr = context.Canceled
+		} else if ok && st.Code() == codes.DeadlineExceeded {
+			ctxErr = context.DeadlineExceeded
 		}
-		st, ok := status.FromError(err)
-		if ok && st.Code() == codes.Canceled {
-			return context.Canceled
+		if ctxErr != nil {
+			if conn := c.c.Conn(); conn != nil {
+				_ = conn.Close()
 			}
-		if ok && st.Code() == codes.DeadlineExceeded {
-			return context.DeadlineExceeded
+			return ctxErr
 		}
 	}