diff --git a/tests/phpunit/includes/testcase.php b/tests/phpunit/includes/testcase.php
index 899050455d..0528cfffa7 100644
--- a/tests/phpunit/includes/testcase.php
+++ b/tests/phpunit/includes/testcase.php
@@ -439,6 +439,21 @@ class WP_UnitTestCase extends PHPUnit_Framework_TestCase {
 		$this->assertEquals( $expected, $actual );
 	}
 
+	/**
+	 * Asserts that the given variable is a multidimensional array, and that all arrays are non-empty.
+	 *
+	 * @param array $array
+	 */
+	function assertNonEmptyMultidimensionalArray( $array ) {
+		$this->assertTrue( is_array( $array ) );
+		$this->assertNotEmpty( $array );
+
+		foreach( $array as $sub_array ) {
+			$this->assertTrue( is_array( $sub_array ) );
+			$this->assertNotEmpty( $sub_array );
+		}
+	}
+
 	/**
 	 * Modify WordPress's query internals as if a given URL has been requested.
 	 *
diff --git a/tests/phpunit/tests/admin/includesTheme.php b/tests/phpunit/tests/admin/includesTheme.php
index 522615c8a0..223560d98d 100644
--- a/tests/phpunit/tests/admin/includesTheme.php
+++ b/tests/phpunit/tests/admin/includesTheme.php
@@ -136,4 +136,31 @@ class Tests_Admin_includesTheme extends WP_UnitTestCase {
 		), get_page_templates() );
 		$this->assertEquals( array(), get_page_templates( null, 'bar' ) );
 	}
+
+	/**
+	 * Test that the list of theme features pulled from the WordPress.org API returns the expected data structure.
+	 *
+	 * Differences in the structure can also trigger failure by causing PHP notices/warnings.
+	 *
+	 * @group external-http
+	 * @ticket 28121
+	 */
+	function test_get_theme_featured_list_api() {
+		wp_set_current_user( $this->factory->user->create( array( 'role' => 'administrator' ) ) );
+		$featured_list_api = get_theme_feature_list( true );
+		$this->assertNonEmptyMultidimensionalArray( $featured_list_api );
+	}
+
+	/**
+	 * Test that the list of theme features hardcoded into Core returns the expected data structure.
+	 *
+	 * Differences in the structure can also trigger failure by causing PHP notices/warnings.
+	 *
+	 * @group external-http
+	 * @ticket 28121
+	 */
+	function test_get_theme_featured_list_hardcoded() {
+		$featured_list_hardcoded = get_theme_feature_list( false );
+		$this->assertNonEmptyMultidimensionalArray( $featured_list_hardcoded );
+	}
 }