Improve is_countable() checks and add test case for \ResourceBunlde class

Author: Ayesh

src/is_countable.php

@@ -9,14 +9,9 @@
    * @return bool Returns TRUE if var is countable, FALSE otherwise.
    */
   function is_countable($var) {
-    return (
-          is_array($var)
-      || (
-          is_object($var)
-          && (
-            $var instanceof \Countable
-            || $var instanceof \SimpleXMLElement
-            || $var instanceof \ResourceBundle
-          )));
+    return is_array($var)
+      || $var instanceof \Countable
+      || $var instanceof \SimpleXMLElement
+      || $var instanceof \ResourceBundle;
   }
 endif;

tests/IsCountableTest.php

@@ -28,7 +28,8 @@ public function getIsCountableData() {
       array(array(1, 2, 3), true),
       array((array) 1, true),
       array((object) array('foo', 'bar', 'baz'), false),
-      array(new \SimpleXMLElement("<xml><tag>1</tag><tag>2</tag></xml>"), true),
+      array(new \SimpleXMLElement('<xml><tag>1</tag><tag>2</tag></xml>'), true),
+      array(new \ResourceBundle('en', null), true),
     );
   }
 }