diff --git a/src/Plugin/migrate/process/Dom.php b/src/Plugin/migrate/process/Dom.php
index b66a511..20e9b8a 100644
--- a/src/Plugin/migrate/process/Dom.php
+++ b/src/Plugin/migrate/process/Dom.php
@@ -66,7 +66,7 @@ class Dom extends ProcessPluginBase {
       $this->idMapLogging = (bool) $this->configuration['warnings_to_idmap'];
     }
     if (isset($this->configuration['non_root'])) {
-      $this->idMapLogging = (bool) $this->configuration['non_root'];
+      $this->nonRoot = (bool) $this->configuration['non_root'];
     }
   }
 
diff --git a/tests/src/Unit/process/DomTest.php b/tests/src/Unit/process/DomTest.php
new file mode 100644
index 0000000..cde4609
--- /dev/null
+++ b/tests/src/Unit/process/DomTest.php
@@ -0,0 +1,65 @@
+<?php
+
+namespace Drupal\Tests\migrate_plus\Unit\process;
+
+use Drupal\Component\Utility\Html;
+use Drupal\migrate\MigrateException;
+use Drupal\migrate\MigrateSkipProcessException;
+use Drupal\migrate\MigrateSkipRowException;
+use Drupal\migrate_plus\Plugin\migrate\process\Dom;
+use Drupal\Tests\migrate\Unit\process\MigrateProcessTestCase;
+
+/**
+ * Tests the dom process plugin.
+ *
+ * @group migrate
+ * @coversDefaultClass \Drupal\migrate_plus\Plugin\migrate\process\Dom
+ */
+class DomTest extends MigrateProcessTestCase {
+
+  /**
+   * @covers ::import
+   */
+  public function testImportNonRoot() {
+    $configuration['method'] = 'import';
+    $value = '<p>A simple paragraph.</p>';
+    $document = (new Dom($configuration, 'dom', []))
+      ->transform($value, $this->migrateExecutable, $this->row, 'destinationproperty');
+    $this->assertTrue($document instanceof \DOMDocument);
+  }
+
+  /**
+   * @covers ::import
+   */
+  public function testImportNonRootInvalidInput() {
+    $configuration['method'] = 'import';
+    $value = [1, 1];
+    $this->setExpectedException(MigrateException::class);
+    (new Dom($configuration, 'dom', []))
+      ->transform($value, $this->migrateExecutable, $this->row, 'destinationproperty');
+  }
+
+  /**
+   * @covers ::export
+   */
+  public function testExportNonRoot( ){
+    $configuration['method'] = 'export';
+    $partial = '<p>A simple paragraph.</p>';
+    $document = Html::load($partial);
+    $value = (new Dom($configuration, 'dom', []))
+      ->transform($document, $this->migrateExecutable, $this->row, 'destinationproperty');
+    $this->assertEquals($value, $partial);
+  }
+
+  /**
+   * @covers ::export
+   */
+  public function testExportNonRootInvalidInput( ){
+    $configuration['method'] = 'export';
+    $partial = '<p>A simple paragraph.</p>';
+    $this->setExpectedException(MigrateException::class);
+    $value = (new Dom($configuration, 'dom', []))
+      ->transform('string in not DOMDocument', $this->migrateExecutable, $this->row, 'destinationproperty');
+  }
+
+}