Fix handling of template template arguments which are not expressions (#199)

src/common/clang_utils.cc

@@ -238,6 +238,11 @@ std::string to_string(const clang::Expr *expr)
     return result;
 }
 
+std::string to_string(const clang::ValueDecl *val)
+{
+    return val->getQualifiedNameAsString();
+}
+
 std::string to_string(const clang::Stmt *stmt)
 {
     const clang::LangOptions lang_options;

src/common/clang_utils.h

@@ -111,6 +111,8 @@ std::string to_string(
 
 std::string to_string(const clang::Expr *expr);
 
+std::string to_string(const clang::ValueDecl *val);
+
 std::string to_string(const clang::Stmt *stmt);
 
 std::string to_string(const clang::FunctionTemplateDecl *decl);

src/sequence_diagram/visitor/call_expression_context.cc

@@ -76,7 +76,7 @@ clang::ASTContext *call_expression_context::get_ast_context() const
     }
 
     if (current_method_decl_ != nullptr) {
-        return &current_function_decl_->getASTContext();
+        return &current_method_decl_->getASTContext();
     }
 
     return nullptr;

src/sequence_diagram/visitor/translation_unit_visitor.cc

@@ -1601,11 +1601,20 @@ bool translation_unit_visitor::process_template_parameters(
                 clang::dyn_cast_or_null<clang::TemplateTemplateParmDecl>(
                     parameter);
             std::optional<std::string> default_arg;
-            if (template_template_parameter->hasDefaultArgument())
+            if (template_template_parameter->hasDefaultArgument()) {
-                default_arg = common::to_string(
+                const auto &def_arg =
                     template_template_parameter->getDefaultArgument()
-                        .getArgument()
+                        .getArgument();
-                        .getAsExpr());
+                if (def_arg.getKind() ==
+                    clang::TemplateArgument::ArgKind::Expression) {
+                    default_arg = common::to_string(def_arg.getAsExpr());
+                }
+                else if (def_arg.getKind() ==
+                    clang::TemplateArgument::ArgKind::Declaration) {
+                    default_arg = common::to_string(def_arg.getAsDecl());
+                }
+            }
+
             auto ct = template_parameter::make_template_template_type(
                 template_template_parameter->getNameAsString(), default_arg,
                 template_template_parameter->isParameterPack());