Update xerrors for go 1.13

Fixes #110

client.go

@@ -4,7 +4,6 @@ import (
 	"encoding/xml"
 	"errors"
 	"fmt"
-	"io"
 	"net"
 	"time"
 
@@ -212,7 +211,7 @@ func (c *Client) Send(packet stanza.Packet) error {
 		return errors.New("cannot marshal packet " + err.Error())
 	}
 
-	return c.sendWithWriter(c.Session.streamLogger, data)
+	return c.sendWithLogger(string(data))
 }
 
 // SendRaw sends an XMPP stanza as a string to the server.
@@ -225,12 +224,12 @@ func (c *Client) SendRaw(packet string) error {
 		return errors.New("client is not connected")
 	}
 
-	return c.sendWithWriter(c.Session.streamLogger, []byte(packet))
+	return c.sendWithLogger(packet)
 }
 
-func (c *Client) sendWithWriter(writer io.Writer, packet []byte) error {
+func (c *Client) sendWithLogger(packet string) error {
 	var err error
-	_, err = writer.Write(packet)
+	_, err = fmt.Fprintf(c.Session.streamLogger, packet)
 	return err
 }
 

client_internal_test.go

@@ -1,19 +0,0 @@
-package xmpp
-
-import (
-	"bytes"
-	"testing"
-)
-
-func TestClient_Send(t *testing.T) {
-	buffer := bytes.NewBufferString("")
-	client := Client{}
-	data := []byte("https://da.wikipedia.org/wiki/J%C3%A6vnd%C3%B8gn")
-	if err := client.sendWithWriter(buffer, data); err != nil {
-		t.Errorf("Writing failed: %v", err)
-	}
-
-	if buffer.String() != string(data) {
-		t.Errorf("Incorrect value sent to buffer: '%s'", buffer.String())
-	}
-}