diff --git a/src/class_diagram/model/class.cc b/src/class_diagram/model/class.cc
index be5ab786..59388157 100644
--- a/src/class_diagram/model/class.cc
+++ b/src/class_diagram/model/class.cc
@@ -87,8 +87,9 @@ std::string class_::base_template() const { return base_template_full_name_; }
 
 bool operator==(const class_ &l, const class_ &r)
 {
-    return (l.name_and_ns() == r.name_and_ns()) &&
-        (l.templates_ == r.templates_);
+    return l.id() == r.id();
+    //(l.name_and_ns() == r.name_and_ns()) &&
+    //    (l.templates_ == r.templates_);
 }
 
 void class_::add_type_alias(type_alias &&ta)
diff --git a/src/class_diagram/model/diagram.cc b/src/class_diagram/model/diagram.cc
index 1873ff3d..0bc93a2f 100644
--- a/src/class_diagram/model/diagram.cc
+++ b/src/class_diagram/model/diagram.cc
@@ -165,8 +165,11 @@ bool diagram::add_class(std::unique_ptr<class_> &&c)
     auto name_with_ns = c->name_and_ns();
     auto name_and_ns = ns | name;
     auto &cc = *c;
+    auto id = cc.id();
 
     if (!has_class(cc)) {
+        if (base_name == "cpp_function_parameter")
+            LOG_DBG("AAAAAAAAAAAAAAAAAAAAAAA");
         if (add_element(ns, std::move(c)))
             classes_.push_back(std::ref(cc));
 
@@ -176,10 +179,13 @@ bool diagram::add_class(std::unique_ptr<class_> &&c)
             throw std::runtime_error(
                 "Invalid element stored in the diagram tree");
 
+        LOG_DBG("Added class {} ({} - [{}])", base_name, full_name, id);
+
         return true;
     }
 
-    LOG_DBG("Class {} ({}) already in the model", base_name, full_name);
+    LOG_DBG(
+        "Class {} ({} - [{}]) already in the model", base_name, full_name, id);
 
     return false;
 }
diff --git a/src/class_diagram/visitor/translation_unit_visitor.cc b/src/class_diagram/visitor/translation_unit_visitor.cc
index 1d8e32fb..e3e1445b 100644
--- a/src/class_diagram/visitor/translation_unit_visitor.cc
+++ b/src/class_diagram/visitor/translation_unit_visitor.cc
@@ -124,8 +124,6 @@ std::string get_source_text(
 {
     clang::LangOptions lo;
 
-    // NOTE: sm.getSpellingLoc() used in case the range corresponds to a
-    // macro/preprocessed source.
     auto start_loc = sm.getSpellingLoc(range.getBegin());
     auto last_token_loc = sm.getSpellingLoc(range.getEnd());
     auto end_loc = clang::Lexer::getLocForEndOfToken(last_token_loc, 0, sm, lo);
@@ -149,6 +147,10 @@ bool translation_unit_visitor::VisitNamespaceDecl(clang::NamespaceDecl *ns)
     if (ns->isAnonymousNamespace() || ns->isInline())
         return true;
 
+    LOG_DBG("= Visiting namespace declaration {} at {}",
+        ns->getQualifiedNameAsString(),
+        ns->getLocation().printToString(source_manager_));
+
     auto package_path = namespace_{common::get_qualified_name(*ns)};
     auto package_parent = package_path;
 
@@ -198,6 +200,10 @@ bool translation_unit_visitor::VisitEnumDecl(clang::EnumDecl *enm)
     if (enm->getNameAsString().empty())
         return true;
 
+    LOG_DBG("= Visiting enum declaration {} at {}",
+        enm->getQualifiedNameAsString(),
+        enm->getLocation().printToString(source_manager_));
+
     auto e_ptr = std::make_unique<enum_>(config_.using_namespace());
     auto &e = *e_ptr;
 
@@ -241,6 +247,10 @@ bool translation_unit_visitor::VisitClassTemplateSpecializationDecl(
     if (source_manager_.isInSystemHeader(cls->getSourceRange().getBegin()))
         return true;
 
+    LOG_DBG("= Visiting template specialization declaration {} at {}",
+        cls->getQualifiedNameAsString(),
+        cls->getLocation().printToString(source_manager_));
+
     // Skip forward declarations
     if (!cls->isCompleteDefinition()) {
         // Register this forward declaration in case there is no complete
@@ -251,7 +261,7 @@ bool translation_unit_visitor::VisitClassTemplateSpecializationDecl(
         // Check if the class was already processed within
         // VisitClassTemplateDecl()
         if (diagram_.has_element(cls->getID()))
-        return true;
+            return true;
 
     // TODO: Add support for classes defined in function/method bodies
     if (cls->isLocalClass())
@@ -289,6 +299,10 @@ bool translation_unit_visitor::VisitTypeAliasTemplateDecl(
     if (source_manager_.isInSystemHeader(cls->getSourceRange().getBegin()))
         return true;
 
+    LOG_DBG("= Visiting template type alias declaration {} at {}",
+        cls->getQualifiedNameAsString(),
+        cls->getLocation().printToString(source_manager_));
+
     auto *template_type_specialization_ptr =
         cls->getTemplatedDecl()
             ->getUnderlyingType()
@@ -320,9 +334,9 @@ bool translation_unit_visitor::VisitClassTemplateDecl(
     if (source_manager_.isInSystemHeader(cls->getSourceRange().getBegin()))
         return true;
 
-    // Skip forward declarations
-    //    if (!cls->getTemplatedDecl()->isCompleteDefinition())
-    //        return true;
+    LOG_DBG("= Visiting class template declaration {} at {}",
+        cls->getQualifiedNameAsString(),
+        cls->getLocation().printToString(source_manager_));
 
     auto c_ptr = create_class_declaration(cls->getTemplatedDecl());
 
@@ -362,9 +376,27 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
     if (source_manager_.isInSystemHeader(cls->getSourceRange().getBegin()))
         return true;
 
+    LOG_DBG("= Visiting class declaration {} at {}",
+        cls->getQualifiedNameAsString(),
+        cls->getLocation().printToString(source_manager_));
+
     // Skip forward declarations
-    if (!cls->isCompleteDefinition())
-        return true;
+    //    if (!cls->isCompleteDefinition())
+    //        return true;
+
+    if (cls->getQualifiedNameAsString() == "cppast::cpp_function_parameter" &&
+        cls->getLocation().printToString(source_manager_) ==
+            "/home/bartek/devel/clang-uml-showcases/cppast/src/../include/"
+            "cppast/cpp_function.hpp:16:7") {
+        LOG_DBG("##############################################################"
+                "##########################");
+        for (const auto &c : diagram().classes()) {
+            LOG_DBG(" >> {} [{}]", c.get().full_name(false), c.get().id());
+        }
+        const auto &ccc = diagram().get_class(cls->getID());
+        if (ccc.has_value())
+            LOG_DBG("---------- {}", ccc.get()->full_name(false));
+    }
 
     // Templated records are handled by VisitClassTemplateDecl()
     if (cls->isTemplated() || cls->isTemplateDecl() ||
@@ -373,8 +405,9 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
         return true;
 
     // Check if the class was already processed within VisitClassTemplateDecl()
-    if (diagram_.has_element(cls->getID()))
-        return true;
+    // auto cls_id = cls->getID();
+    // if (diagram_.has_element(cls_id))
+    //    return true;
 
     // TODO: Add support for classes defined in function/method bodies
     if (cls->isLocalClass())
@@ -385,9 +418,12 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
     if (!c_ptr)
         return true;
 
-    auto &class_model = *c_ptr;
+    auto &class_model = diagram().get_class(cls->getID()).has_value()
+        ? *diagram().get_class(cls->getID()).get()
+        : *c_ptr;
 
-    process_class_declaration(*cls, class_model);
+    if (cls->isCompleteDefinition())
+        process_class_declaration(*cls, class_model);
 
     auto id = class_model.id();
     if (!cls->isCompleteDefinition()) {
@@ -403,6 +439,10 @@ bool translation_unit_visitor::VisitCXXRecordDecl(clang::CXXRecordDecl *cls)
 
         diagram_.add_class(std::move(c_ptr));
     }
+    else {
+        LOG_DBG("Skipping class {} with id {}", class_model.full_name(),
+            class_model.id());
+    }
 
     return true;
 }
@@ -901,7 +941,7 @@ void translation_unit_visitor::process_function_parameter(
         const auto *default_arg = p.getDefaultArg();
         if (default_arg != nullptr) {
             auto default_arg_str =
-                default_arg->getSourceRange().printToString(source_manager_);
+                get_source_text(default_arg->getSourceRange(), source_manager_);
             parameter.set_default_value(default_arg_str);
         }
     }
@@ -1864,7 +1904,7 @@ void translation_unit_visitor::add_incomplete_forward_declarations()
 
 void translation_unit_visitor::finalize()
 {
-    add_incomplete_forward_declarations();
+//    add_incomplete_forward_declarations();
 }
 
 bool translation_unit_visitor::simplify_system_template(
diff --git a/src/common/generators/plantuml/generator.h b/src/common/generators/plantuml/generator.h
index 44af1602..5d262ea0 100644
--- a/src/common/generators/plantuml/generator.h
+++ b/src/common/generators/plantuml/generator.h
@@ -262,6 +262,9 @@ public:
     {
         visitor_.TraverseDecl(ast_context.getTranslationUnitDecl());
         visitor_.finalize();
+
+//        LOG_DBG("= Finalized translation unit: {}",
+//            ast_context.getTranslationUnitDecl());
     }
 };
 
@@ -287,6 +290,8 @@ public:
 protected:
     bool BeginSourceFileAction(clang::CompilerInstance &ci) override
     {
+        LOG_DBG("Visiting source file: {}", getCurrentFile().str());
+
         if constexpr (std::is_same_v<DiagramModel,
                           clanguml::include_diagram::model::diagram>) {
             auto find_includes_callback =
@@ -351,11 +356,10 @@ std::unique_ptr<DiagramModel> generate(
         const auto matches = glob::rglob(g);
         std::copy(matches.begin(), matches.end(),
             std::back_inserter(translation_units));
-
-        LOG_DBG(
-            "Found translation units: {}", fmt::join(translation_units, ", "));
     }
 
+    LOG_DBG("Found translation units: {}", fmt::join(translation_units, ", "));
+
     clang::tooling::ClangTool clang_tool(db, translation_units);
     auto action_factory =
         std::make_unique<diagram_action_visitor_factory<DiagramModel,
diff --git a/tests/t00003/test_case.h b/tests/t00003/test_case.h
index 3cf33cd9..e112743c 100644
--- a/tests/t00003/test_case.h
+++ b/tests/t00003/test_case.h
@@ -48,6 +48,11 @@ TEST_CASE("t00003", "[test-case][class]")
     REQUIRE_THAT(puml, (IsMethod<Public>("basic_method")));
     REQUIRE_THAT(puml, (IsMethod<Public, Static>("static_method", "int")));
     REQUIRE_THAT(puml, (IsMethod<Public, Const>("const_method")));
+    REQUIRE_THAT(puml, (IsMethod<Public>("default_int", "int", "int i = 12")));
+    REQUIRE_THAT(puml,
+        (IsMethod<Public>("default_string", "std::string",
+            "int i, std::string s = \"abc\"")));
+
     REQUIRE_THAT(puml, (IsMethod<Protected>("protected_method")));
     REQUIRE_THAT(puml, (IsMethod<Private>("private_method")));
     REQUIRE_THAT(puml, (IsField<Public>("public_member", "int")));
diff --git a/tests/t00048/.clang-uml b/tests/t00048/.clang-uml
new file mode 100644
index 00000000..d95684b8
--- /dev/null
+++ b/tests/t00048/.clang-uml
@@ -0,0 +1,16 @@
+compilation_database_dir: ..
+output_directory: puml
+diagrams:
+  t00048_class:
+    type: class
+    glob:
+#      - ../../tests/t00048/*.cc
+#      - ../../tests/t00048/t00048.cc
+#
+      - ../../tests/t00048/b_t00048.cc
+      - ../../tests/t00048/a_t00048.cc
+    using_namespace: clanguml::t00048
+    parse_includes: true
+    include:
+      namespaces:
+        - clanguml::t00048
\ No newline at end of file
diff --git a/tests/t00048/a_t00048.cc b/tests/t00048/a_t00048.cc
new file mode 100644
index 00000000..b67263bb
--- /dev/null
+++ b/tests/t00048/a_t00048.cc
@@ -0,0 +1,9 @@
+#include "a_t00048.h"
+
+namespace clanguml {
+namespace t00048 {
+
+void A::foo() {}
+
+}
+}
\ No newline at end of file
diff --git a/tests/t00048/a_t00048.h b/tests/t00048/a_t00048.h
new file mode 100644
index 00000000..c130ca0f
--- /dev/null
+++ b/tests/t00048/a_t00048.h
@@ -0,0 +1,21 @@
+#include "t00048.h"
+
+#pragma once
+
+namespace clanguml {
+namespace t00048 {
+
+struct A : public Base {
+    int a;
+
+    void foo() override;
+};
+
+template <typename T> struct ATemplate : public BaseTemplate<T> {
+    T a;
+
+    void foo() override {}
+};
+
+}
+}
\ No newline at end of file
diff --git a/tests/t00048/b_t00048.cc b/tests/t00048/b_t00048.cc
new file mode 100644
index 00000000..1897152e
--- /dev/null
+++ b/tests/t00048/b_t00048.cc
@@ -0,0 +1,9 @@
+#include "b_t00048.h"
+
+namespace clanguml {
+namespace t00048 {
+
+void B::foo() {}
+
+}
+}
\ No newline at end of file
diff --git a/tests/t00048/b_t00048.h b/tests/t00048/b_t00048.h
new file mode 100644
index 00000000..95c14bb4
--- /dev/null
+++ b/tests/t00048/b_t00048.h
@@ -0,0 +1,21 @@
+#include "t00048.h"
+
+#pragma once
+
+namespace clanguml {
+namespace t00048 {
+
+struct B : public Base {
+    int b;
+
+    void foo() override;
+};
+
+template <typename T> struct BTemplate : public BaseTemplate<T> {
+    T b;
+
+    void foo() override {}
+};
+
+}
+}
\ No newline at end of file
diff --git a/tests/t00048/t00048.cc b/tests/t00048/t00048.cc
new file mode 100644
index 00000000..22b281f8
--- /dev/null
+++ b/tests/t00048/t00048.cc
@@ -0,0 +1,7 @@
+#include "t00048.h"
+
+namespace clanguml {
+namespace t00048
+{
+}
+}
\ No newline at end of file
diff --git a/tests/t00048/t00048.h b/tests/t00048/t00048.h
new file mode 100644
index 00000000..e7aac8c9
--- /dev/null
+++ b/tests/t00048/t00048.h
@@ -0,0 +1,19 @@
+#pragma once
+
+namespace clanguml {
+namespace t00048 {
+
+struct Base {
+    int base;
+
+    virtual void foo() = 0;
+};
+
+template <typename T> struct BaseTemplate {
+    T base;
+
+    virtual void foo() = 0;
+};
+
+}
+}
\ No newline at end of file
diff --git a/tests/t00048/test_case.h b/tests/t00048/test_case.h
new file mode 100644
index 00000000..a0575fd3
--- /dev/null
+++ b/tests/t00048/test_case.h
@@ -0,0 +1,75 @@
+/**
+ * tests/t00048/test_case.h
+ *
+ * Copyright (c) 2021-2022 Bartek Kryza <bkryza@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+TEST_CASE("t00048", "[test-case][class]")
+{
+    auto [config, db] = load_config("t00048");
+
+    auto diagram = config.diagrams["t00048_class"];
+
+    REQUIRE(diagram->name == "t00048_class");
+
+    auto model = generate_class_diagram(*db, diagram);
+
+    REQUIRE(model->name() == "t00048_class");
+
+    auto puml = generate_class_puml(diagram, *model);
+    AliasMatcher _A(puml);
+
+    REQUIRE_THAT(puml, StartsWith("@startuml"));
+    REQUIRE_THAT(puml, EndsWith("@enduml\n"));
+
+    
+    // Check if all classes exist
+    REQUIRE_THAT(puml, IsAbstractClass(_A("Base")));
+    REQUIRE_THAT(puml, IsClass(_A("A")));
+    REQUIRE_THAT(puml, IsClass(_A("B")));
+
+
+    // Check if class templates exist
+    REQUIRE_THAT(puml, IsAbstractClassTemplate("BaseTemplate", "T"));
+    REQUIRE_THAT(puml, IsClassTemplate("ATemplate", "T"));
+    REQUIRE_THAT(puml, IsClassTemplate("BTemplate", "T"));
+
+    // Check if all enums exist
+    //REQUIRE_THAT(puml, IsEnum(_A("Lights")));
+    
+    // Check if all inner classes exist
+    //REQUIRE_THAT(puml, IsInnerClass(_A("A"), _A("AA")));
+
+    // Check if all inheritance relationships exist
+    REQUIRE_THAT(puml, IsBaseClass(_A("Base"), _A("A")));
+    REQUIRE_THAT(puml, IsBaseClass(_A("Base"), _A("B")));
+
+    // Check if all methods exist
+    //REQUIRE_THAT(puml, (IsMethod<Public, Const>("foo")));
+    
+    // Check if all fields exist
+    //REQUIRE_THAT(puml, (IsField<Private>("private_member", "int")));
+    
+    // Check if all relationships exist
+    //REQUIRE_THAT(puml, IsAssociation(_A("D"), _A("A"), "-as"));
+    //REQUIRE_THAT(puml, IsDependency(_A("R"), _A("B")));
+    //REQUIRE_THAT(puml, IsAggregation(_A("R"), _A("D")));
+    //REQUIRE_THAT(puml, IsComposition(_A("R"), _A("D")));
+    //REQUIRE_THAT(puml, IsInstantiation(_A("ABCD::F<T>"), _A("F<int>")));
+
+
+    save_puml(
+        "./" + config.output_directory() + "/" + diagram->name + ".puml", puml);
+}
\ No newline at end of file
diff --git a/tests/test_cases.cc b/tests/test_cases.cc
index 6090872d..62e9dfd7 100644
--- a/tests/test_cases.cc
+++ b/tests/test_cases.cc
@@ -236,6 +236,7 @@ using namespace clanguml::test::matchers;
 #include "t00045/test_case.h"
 #include "t00046/test_case.h"
 #include "t00047/test_case.h"
+#include "t00048/test_case.h"
 
 ////
 //// Sequence diagram tests
diff --git a/tests/test_cases.h b/tests/test_cases.h
index 5020c6c9..84aae50f 100644
--- a/tests/test_cases.h
+++ b/tests/test_cases.h
@@ -229,6 +229,14 @@ ContainsMatcher IsAbstractClass(std::string const &str,
     return ContainsMatcher(CasedString("abstract " + str, caseSensitivity));
 }
 
+ContainsMatcher IsAbstractClassTemplate(std::string const &str,
+    std::string const &tmplt,
+    CaseSensitive::Choice caseSensitivity = CaseSensitive::Yes)
+{
+    return ContainsMatcher(CasedString(
+        fmt::format("abstract \"{}<{}>\"", str, tmplt), caseSensitivity));
+}
+
 ContainsMatcher IsBaseClass(std::string const &base, std::string const &sub,
     CaseSensitive::Choice caseSensitivity = CaseSensitive::Yes)
 {
@@ -376,7 +384,7 @@ ContainsMatcher HasLink(std::string const &alias, std::string const &link,
 
 template <typename... Ts>
 ContainsMatcher IsMethod(std::string const &name,
-    std::string const &type = "void",
+    std::string const &type = "void", std::string const &params = "",
     CaseSensitive::Choice caseSensitivity = CaseSensitive::Yes)
 {
     std::string pattern;
@@ -395,7 +403,7 @@ ContainsMatcher IsMethod(std::string const &name,
 
     pattern += name;
 
-    pattern += "()";
+    pattern += "(" + params + ")";
 
     if constexpr (has_type<Const, Ts...>())
         pattern += " const";