diff --git a/tests/unit/suites/issues/Issue13382Test.php b/tests/unit/suites/issues/Issue13382Test.php
new file mode 100644
index 0000000000000..a1cfcdfbe662d
--- /dev/null
+++ b/tests/unit/suites/issues/Issue13382Test.php
@@ -0,0 +1,73 @@
+<?php
+/**
+ * @package     Joomla.UnitTest
+ *
+ * @copyright   Copyright (C) 2005 - 2017 Open Source Matters, Inc. All rights reserved.
+ * @license     GNU General Public License version 2 or later; see LICENSE
+ *
+ * @since       __DEPLOY_VERSION__
+ */
+
+/**
+ * Tests for issue 13382
+ *
+ * https://issues.joomla.org/tracker/joomla-cms/13382
+ *
+ * Loading a custom field can result in a Fatal Error, if a core field exists with the same filename, and the custom
+ * field extends the core field.
+ *
+ * Consider a file `testfields/radio.php` containing
+ *
+ * ```php
+ * <?php
+ *
+ * class TestFormFieldRadio extends JFormFieldRadio {}
+ * ```
+ *
+ * Calling `JFormHelper::loadFieldClass('radio')` will yield in a Fatal error: Class 'JFormFieldRadio' not found.
+ *
+ * There are two reasons for this.
+ *
+ * 1. JLoader cannot autoload JFormFieldRadio, because the class name (JFormField*) does not match the path name
+ *    (joomla/form/fields/* - notice the plural on fields).
+ *
+ * 2. JFormHelper cannot load JFormFieldRadio, because custom paths are scanned first, and the requested field type
+ *    ('radio') gets resolved before the core classes are reached.
+ *
+ * Solution:
+ *
+ * Require the core field directly:
+ *
+ * ```php
+ * <?php
+ * require_once JPATH_LIBRARIES . '/joomla/form/fields/radio.php';
+ *
+ * class TestFormFieldRadio extends JFormFieldRadio {}
+ * ```
+ *
+ * and use `JFormHelper::loadFieldClass` properly with 'test.radio' instead of 'radio'.
+ *
+ * @since  __DEPLOY_VERSION__
+ */
+class Issue13382Test extends PHPUnit_Framework_TestCase
+{
+	/**
+	 * Test expected behaviour
+	 *
+	 * `JFormHelper::loadFieldClass('radio')` should return 'JFormFieldRadio'
+	 * `JFormHelper::loadFieldClass('test.radio')` should return 'TestFormFieldRadio'
+	 *
+	 * @see      https://issues.joomla.org/tracker/joomla-cms/13382#event-231756
+	 *
+	 * @testdox  Custom field types can extend core types with the same filename
+	 *
+	 * @since    __DEPLOY_VERSION__
+	 */
+	public function testIssue13382()
+	{
+		JFormHelper::addFieldPath(__DIR__ . '/fixtures/issue13382');
+
+		$this->assertEquals('JFormFieldRadio', JFormHelper::loadFieldClass('radio'));
+		$this->assertEquals('TestFormFieldRadio', JFormHelper::loadFieldClass('test.radio'));
+	}
+}
diff --git a/tests/unit/suites/issues/fixtures/issue13382/radio.php b/tests/unit/suites/issues/fixtures/issue13382/radio.php
new file mode 100644
index 0000000000000..0e658458461dc
--- /dev/null
+++ b/tests/unit/suites/issues/fixtures/issue13382/radio.php
@@ -0,0 +1,7 @@
+<?php
+require_once JPATH_LIBRARIES . '/joomla/form/fields/radio.php';
+
+class TestFormFieldRadio extends JFormFieldRadio
+{
+
+}