Enforce string type for string operations

split: b40122acb6c4acafd4e04ff3cef4f202876eb2cb

Author: kylekatarnls

Diff for: Compiler/NodeCompiler/ImportNodeCompiler.php

@@ -23,7 +23,7 @@ class ImportNodeCompiler extends AbstractNodeCompiler
     protected function isPugImport($path)
     {
         $compiler = $this->getCompiler();
-        $extension = pathinfo($path, PATHINFO_EXTENSION) ?: '';
+        $extension = pathinfo((string) $path, PATHINFO_EXTENSION);
         $extensions = $compiler->getOption('extensions');
 
         if ($extension === '') {
@@ -72,7 +72,7 @@ public function compileNode(NodeInterface $node, ElementInterface $parent = null
 
         $paths = $isAbsolutePath
             ? null
-            : [dirname($compiler->getPath()) ?: '.'];
+            : [dirname((string) $compiler->getPath()) ?: '.'];
 
         $path = $compiler->resolve($node->getPath(), $paths);
         $compiler->registerImportPath($path);