check for class existence before checking strings

Author: pxpm

src/app/Library/CrudPanel/Traits/Relationships.php

@@ -342,6 +342,14 @@ private function modelMethodIsRelationship($model, $method)
 
         if ($returnType) {
             $returnType = $returnType->getName();
+
+            // this check is to make sure we don't autoload the class when checking strings instead of objects.
+            // the third parameter of is_a() allow us to check strings, but it also autoloads the class
+            // in case it does not exists. The classes we want to check against EXIST.
+            if(!class_exists($returnType, false)) {
+                return false;
+            }
+            // the above check 
             if (is_a($returnType, 'Illuminate\Database\Eloquent\Casts\Attribute', true)) {
                 return false;
             }