Applying bugprone-narrowing-conversions clang-tidy fixes

.clang-tidy

@@ -34,6 +34,7 @@ Checks: >-
   -readability-inconsistent-declaration-parameter-name,
   -readability-identifier-naming,
   -readability-redundant-smartptr-get,
+  -readability-convert-member-functions-to-static,
   -darwin*,
   -zircon*
 WarningsAsErrors: '*'

src/class_diagram/generators/plantuml/class_diagram_generator.cc

@@ -194,10 +194,14 @@ void generator::generate(const class_ &c, std::ostream &ostr) const
 
         std::string destination;
         try {
-            destination = r.destination();
+            auto target_element = m_model.get(r.destination());
+            if (!target_element.has_value())
+                throw error::uml_alias_missing{
+                    fmt::format("Missing element in the model for ID: {}",
+                        r.destination())};
+
+            destination = target_element.value().full_name(false);
 
-            // TODO: Refactor destination to a namespace qualified entity
-            //       name
             if (util::starts_with(destination, std::string{"::"}))
                 destination = destination.substr(2, destination.size());
 

src/class_diagram/visitor/translation_unit_visitor.cc

@@ -1409,7 +1409,8 @@ std::unique_ptr<class_> translation_unit_visitor::
     template_instantiation.set_name(template_decl->getNameAsString());
     template_instantiation.set_namespace(ns);
     template_instantiation.set_id(template_decl->getID() +
-        (std::hash<std::string>{}(full_template_specialization_name) >> 4));
+        static_cast<id_t>(
+            std::hash<std::string>{}(full_template_specialization_name) >> 4u));
 
     build_template_instantiation_process_template_arguments(parent,
         template_base_params,
@@ -1661,7 +1662,7 @@ void translation_unit_visitor::
         const std::string &full_template_specialization_name,
         const clang::TemplateDecl *template_decl)
 {
-    auto arg_index = 0U;
+    auto arg_index = 0;
     for (const auto &arg : template_args) {
         const auto argument_kind = arg.getKind();
         template_parameter argument;

src/common/clang_utils.cc

@@ -244,7 +244,7 @@ bool is_subexpr_of(const clang::Stmt *parent_stmt, const clang::Stmt *sub_stmt)
 
 template <> id_t to_id(const std::string &full_name)
 {
-    return std::hash<std::string>{}(full_name) >> 3;
+    return static_cast<id_t>(std::hash<std::string>{}(full_name) >> 3u);
 }
 
 template <> id_t to_id(const clang::NamespaceDecl &declaration)

src/common/visitor/comment/clang_visitor.cc

@@ -91,7 +91,7 @@ void clang_visitor::visit(
             const auto *command_info =
                 traits.getCommandInfo(command->getCommandID());
 
-            if (command_info->IsBlockCommand && command_info->NumArgs == 0) {
+            if (command_info->IsBlockCommand && command_info->NumArgs == 0u) {
                 // Visit block command with a single text argument, e.g.:
                 //    \brief text
                 //    \todo text