container: root: macro: common: throw if invalid loading path

- Fixes silent failure when attempting to load non-existent/invalid path
- Applies to any macro, plugin or path that's loaded through this class

container/src/root/macro/common/utility.hh

@@ -24,6 +24,7 @@
 #define CONTAINER_SRC_ROOT_MACRO_COMMON_UTILITY_HH_
 
 #include <ctime>
+#include <filesystem>
 #include <initializer_list>
 #include <iostream>
 #include <string>
@@ -72,6 +73,18 @@ class Command final
   //! \brief Load given file path
   static void load(const std::string& path)
   {
+    std::filesystem::path p(path);
+    if (!std::filesystem::exists(p))
+      {
+        throw std::runtime_error(
+            std::string{"'" + path + "' does not exist!"}.c_str());
+      }
+    if (!std::filesystem::is_regular_file(p))
+      {
+        throw std::runtime_error(
+            std::string{"'" + path + "' is not a regular file!"}.c_str());
+      }
+
     std::string cmd{".L " + path};
     Command::cmd_handler({cmd});
   }