diff --git a/core/modules/serialization/lib/Drupal/serialization/Encoder/XmlEncoder.php b/core/modules/serialization/lib/Drupal/serialization/Encoder/XmlEncoder.php
index 1f25389df441e9ac9f10be4f025cece6b8e78924..3b19a44da95099eefe692fec607e3cebaab606a5 100644
--- a/core/modules/serialization/lib/Drupal/serialization/Encoder/XmlEncoder.php
+++ b/core/modules/serialization/lib/Drupal/serialization/Encoder/XmlEncoder.php
@@ -35,10 +35,26 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
   protected $baseEncoder;
 
   /**
-   * Constucts the XmlEncoder object, creating a BaseXmlEncoder class also.
+   * Gets the base encoder instance.
+   *
+   * @return \Symfony\Component\Serializer\Encoder\XmlEncoder
+   *   The base encoder.
+   */
+  public function getBaseEncoder() {
+    if (!isset($this->baseEncoder)) {
+      $this->baseEncoder = new BaseXmlEncoder();
+    }
+
+    return $this->baseEncoder;
+  }
+
+  /**
+   * Sets the base encoder instance.
+   *
+   * @param \Symfony\Component\Serializer\Encoder\XmlEncoder $encoder
    */
-  public function __construct() {
-    $this->baseEncoder = new BaseXmlEncoder();
+  public function setBaseEncoder($encoder) {
+    $this->baseEncoder = $encoder;
   }
 
   /**
@@ -46,7 +62,7 @@ public function __construct() {
    */
   public function encode($data, $format, array $context = array()){
     $normalized = $this->serializer->normalize($data, $format, $context);
-    return $this->baseEncoder->encode($normalized, $format, $context);
+    return $this->getBaseEncoder()->encode($normalized, $format, $context);
   }
 
   /**
@@ -60,7 +76,7 @@ public function supportsEncoding($format) {
    * Implements \Symfony\Component\Serializer\Encoder\EncoderInterface::decode().
    */
   public function decode($data, $format, array $context = array()){
-    return $this->baseEncoder->decode($data, $format, $context);
+    return $this->getBaseEncoder()->decode($data, $format, $context);
   }
 
   /**
diff --git a/core/modules/serialization/tests/Drupal/serialization/Tests/Encoder/XmlEncoderTest.php b/core/modules/serialization/tests/Drupal/serialization/Tests/Encoder/XmlEncoderTest.php
new file mode 100644
index 0000000000000000000000000000000000000000..eef24b978ab35a3d5e34edd073381e084f2849d8
--- /dev/null
+++ b/core/modules/serialization/tests/Drupal/serialization/Tests/Encoder/XmlEncoderTest.php
@@ -0,0 +1,104 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\serialization\Tests\Encoder\XmlEncoderTest.
+ */
+
+namespace Drupal\serialization\Tests\Encoder;
+
+use Drupal\serialization\Encoder\XmlEncoder;
+use Drupal\Tests\UnitTestCase;
+
+/**
+ * Tests the XmlEncoder class.
+ *
+ * @see \Drupal\serialization\Encoder\XmlEncoder
+ */
+class XmlEncoderTest extends UnitTestCase {
+
+  /**
+   * The XmlEncoder instance.
+   *
+   * @var \Drupal\serialization\Encoder\XmlEncoder
+   */
+  protected $encoder;
+
+  /**
+   * @var \Symfony\Component\Serializer\Encoder\XmlEncoder|\PHPUnit_Framework_MockObject_MockObject
+   */
+  protected $baseEncoder;
+
+  /**
+   * An array of test data.
+   *
+   * @var array
+   */
+  protected $testArray = array('test' => 'test');
+
+  public static function getInfo() {
+    return array(
+      'name' => 'XmlEncoderTest',
+      'description' => 'Tests the XmlEncoder class.',
+      'group' => 'Serialization',
+    );
+  }
+
+  public function setUp() {
+    $this->baseEncoder = $this->getMock('Symfony\Component\Serializer\Encoder\XmlEncoder');
+    $this->encoder = new XmlEncoder();
+    $this->encoder->setBaseEncoder($this->baseEncoder);
+  }
+
+  /**
+   * Tests the supportsEncoding() method.
+   */
+  public function testSupportsEncoding() {
+    $this->assertTrue($this->encoder->supportsEncoding('xml'));
+    $this->assertFalse($this->encoder->supportsEncoding('json'));
+  }
+
+  /**
+   * Tests the supportsDecoding() method.
+   */
+  public function testSupportsDecoding() {
+    $this->assertTrue($this->encoder->supportsDecoding('xml'));
+    $this->assertFalse($this->encoder->supportsDecoding('json'));
+  }
+
+  /**
+   * Tests the encode() method.
+   */
+  public function testEncode() {
+    $serializer = $this->getMockBuilder('Symfony\Component\Serializer\Serializer')
+      ->disableOriginalConstructor()
+      ->setMethods(array('normalize'))
+      ->getMock();
+    $serializer->expects($this->once())
+      ->method('normalize')
+      ->with($this->testArray, 'test', array())
+      ->will($this->returnValue($this->testArray));
+
+    $this->encoder->setSerializer($serializer);
+
+    $this->baseEncoder->expects($this->once())
+      ->method('encode')
+      ->with($this->testArray, 'test', array())
+      ->will($this->returnValue('test'));
+
+    $this->assertEquals('test', $this->encoder->encode($this->testArray, 'test'));
+  }
+
+  /**
+   * Tests the decode() method.
+   */
+  public function testDecode() {
+    $this->baseEncoder->expects($this->once())
+      ->method('decode')
+      ->with('test', 'test', array())
+      ->will($this->returnValue($this->testArray));
+
+    $this->assertEquals($this->testArray, $this->encoder->decode('test', 'test'));
+  }
+
+}