Supports string and array settings for file_extensions config

Author: Chris Hulton

Runner.php

@@ -92,7 +92,13 @@ public function run($files)
 $phpmd = new PHPMD();
 
 if (isset($this->config['config']['file_extensions'])) {
-$phpmd->setFileExtensions(explode(',', $this->config['config']['file_extensions']));
+$fileExtensions = $this->config['config']['file_extensions'];
+
+if (is_string($fileExtensions)) {
+$fileExtensions = explode(',', $fileExtensions);
+}
+
+$phpmd->setFileExtensions($fileExtensions);
 }
 
 $rulesets = Runner::RULESETS;