diff --git a/core/modules/system/src/Tests/Theme/MessageRenderTest.php b/core/modules/system/src/Tests/Theme/MessageRenderTest.php
new file mode 100644
index 0000000..10125d5
--- /dev/null
+++ b/core/modules/system/src/Tests/Theme/MessageRenderTest.php
@@ -0,0 +1,55 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\system\Tests\Theme\MessageRenderTest.
+ */
+
+namespace Drupal\system\Tests\Theme;
+
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests rendering of status, error and warning messages.
+ *
+ * @group Theme
+ */
+class MessageRenderTest extends WebTestBase{
+
+  /**
+   * Tests that status, error and warning messages
+   * Get the correct classes.
+   */
+  function testMessageClasses() {
+    // Set some messages with ascending severity.
+    $this->set_messages_assert_classes('status', 'warning', 'error');
+    $this->set_messages_assert_classes('status', 'error', 'warning');
+    $this->set_messages_assert_classes('error', 'status', 'warning');
+    $this->set_messages_assert_classes('error', 'warning', 'status');
+    $this->set_messages_assert_classes('warning', 'error', 'status');
+    $this->set_messages_assert_classes('warning', 'status', 'error');
+  }
+
+  /**
+   * Utility function to set some messages and
+   * assert their css classes after rendering.
+   */
+  private function set_messages_assert_classes($severity1, $severity2, $severity3){
+    drupal_set_message($this->randomString(), $severity1);
+    drupal_set_message($this->randomString(), $severity2);
+    drupal_set_message($this->randomString(), $severity3);
+
+    $render = array('#theme' => 'status_messages');
+    $this->setRawContent(drupal_render($render));
+
+    $this->assertRaw('messages messages--status');
+    $this->assertRaw('messages messages--warning');
+    $this->assertRaw('messages messages--error');
+    $this->assertNoRaw('messages--status messages--warning"');
+    $this->assertNoRaw('messages--status messages--error"');
+    $this->assertNoRaw('messages--warning messages--status"');
+    $this->assertNoRaw('messages--warning messages--error"');
+    $this->assertNoRaw('messages--error messages--status"');
+    $this->assertNoRaw('messages--error messages--warning"');
+  }
+}
\ No newline at end of file