From 17de8b7ded42a2be56f4f2a1c44c9dafe6a36f35 Mon Sep 17 00:00:00 2001
From: Bartek Kryza <bkryza@gmail.com>
Date: Sat, 5 Mar 2022 22:10:27 +0100
Subject: [PATCH] Prevent infinite recursion during alias resolution #18

---
 src/class_diagram/visitor/translation_unit_context.cc | 7 ++++++-
 src/class_diagram/visitor/translation_unit_visitor.cc | 7 +++++--
 src/cx/util.cc                                        | 4 ++++
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/src/class_diagram/visitor/translation_unit_context.cc b/src/class_diagram/visitor/translation_unit_context.cc
index dd66ed05..ae2fe3fb 100644
--- a/src/class_diagram/visitor/translation_unit_context.cc
+++ b/src/class_diagram/visitor/translation_unit_context.cc
@@ -115,7 +115,12 @@ translation_unit_context::get_type_alias_final(const cppast::cpp_type &t) const
         cx::util::full_name(cppast::remove_cv(t), entity_index_, false);
 
     if (has_type_alias(type_full_name)) {
-        return get_type_alias_final(alias_index_.at(type_full_name).get());
+        const auto &alias_type = alias_index_.at(type_full_name).get();
+        // Prevent infinite recursion
+        if (type_full_name !=
+            cx::util::full_name(
+                cppast::remove_cv(alias_type), entity_index_, false))
+            return get_type_alias_final(alias_type);
     }
 
     return type_safe::ref(t);
diff --git a/src/class_diagram/visitor/translation_unit_visitor.cc b/src/class_diagram/visitor/translation_unit_visitor.cc
index 0f98de94..7b2661ec 100644
--- a/src/class_diagram/visitor/translation_unit_visitor.cc
+++ b/src/class_diagram/visitor/translation_unit_visitor.cc
@@ -1349,8 +1349,11 @@ bool translation_unit_visitor::find_relationships_in_user_defined_type(
     if (ctx.has_type_alias(fn)) {
         LOG_DBG("Find relationship in alias of {} | {}", fn,
             cppast::to_string(ctx.get_type_alias(fn).get()));
-        found = find_relationships(
-            ctx.get_type_alias(fn).get(), relationships, relationship_type);
+        if (cppast::to_string(t_) == fn)
+            found = true;
+        else
+            found = find_relationships(
+                ctx.get_type_alias(fn).get(), relationships, relationship_type);
     }
     return found;
 }
diff --git a/src/cx/util.cc b/src/cx/util.cc
index 4907b56e..7c780a6a 100644
--- a/src/cx/util.cc
+++ b/src/cx/util.cc
@@ -88,6 +88,10 @@ std::string ns(const cppast::cpp_entity &e)
         }
         it = it.value().parent();
     }
+
+    if (res.empty())
+        return "";
+
     std::reverse(res.begin(), res.end());
 
     return fmt::format("{}", fmt::join(res, "::"));