Replace private methods with generate_index_name() function

src/Model/IndexInput.php

@@ -50,7 +50,7 @@ class IndexInput implements Serializable
         }
 
         if ( ! isset($index['name'])) {
-            $index['name'] = $this->generateName($index['key']);
+            $index['name'] = \MongoDB\generate_index_name($index['key']);
         }
 
         if ( ! is_string($index['name'])) {
@@ -80,22 +80,4 @@ class IndexInput implements Serializable
     {
         return $this->index;
     }
-
-    /**
-     * Generates an index name from its key specification.
-     *
-     * @param array|object $key Document containing fields mapped to values,
-     *                          which denote order or an index type
-     * @return string
-     */
-    private function generateName($key)
-    {
-        $name = '';
-
-        foreach ($key as $field => $type) {
-            $name .= ($name != '' ? '_' : '') . $field . '_' . $type;
-        }
-
-        return $name;
-    }
 }

src/Operation/Count.php

@@ -49,7 +49,7 @@ class Count implements Executable
     {
         if (isset($options['hint'])) {
             if (is_array($options['hint']) || is_object($options['hint'])) {
-                $options['hint'] = $this->generateIndexName($options['hint']);
+                $options['hint'] = \MongoDB\generate_index_name($options['hint']);
             }
 
             if ( ! is_string($options['hint'])) {
@@ -121,22 +121,4 @@ class Count implements Executable
 
         return new Command($cmd);
     }
-
-    /**
-     * Generates an index name from its key specification.
-     *
-     * @param array|object $key Document containing fields mapped to values,
-     *                          which denote order or an index type
-     * @return string
-     */
-    private function generateIndexName($key)
-    {
-        $name = '';
-
-        foreach ($key as $field => $type) {
-            $name .= ($name != '' ? '_' : '') . $field . '_' . $type;
-        }
-
-        return $name;
-    }
 }