scrutinizer fixes

Author: Oscar Otero

src/PhpFunctionsScanner.php

@@ -22,6 +22,10 @@ public function scan(string $code, string $filename = null): array
     {
         $ast = $this->parser->parse($code);
 
+        if (empty($ast)) {
+            return [];
+        }
+
         $traverser = new NodeTraverser();
         $visitor = new PhpNodeVisitor($filename, $this->validFunctions);
         $traverser->addVisitor($visitor);

src/PhpNodeVisitor.php

@@ -57,7 +57,6 @@ public function getFunctions(): array
 
     protected function createFunction(FuncCall $node): ParsedFunction
     {
-        $arguments = [];
         $function = new ParsedFunction(
             $node->name->getLast(),
             $this->filename,