fix: global namespace is always created

Author: fpelliccioni

src/lib/AST/ASTVisitor.cpp

@@ -374,6 +374,9 @@ class ASTVisitor
         // dependencies will be tracked, but not extracted
         traverseDecl(context_.getTranslationUnitDecl());
 
+        // This is to ensure that the global namespace is always present
+        getOrCreateInfo<NamespaceInfo>(SymbolID::global);
+
         // if dependency extraction is disabled, we are done
         if(config_->referencedDeclarations ==
             ConfigImpl::SettingsImpl::ExtractPolicy::Never)

test-files/golden-tests/empty.cpp

@@ -0,0 +1 @@
+

test-files/golden-tests/empty.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<mrdocs xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xsi:noNamespaceSchemaLocation="https://github.com/cppalliance/mrdocs/raw/develop/mrdocs.rnc">
+<namespace id="//////////////////////////8=">
+</namespace>
+</mrdocs>