diff --git a/main.cpp b/main.cpp
index bef8d16a..8f56084b 100644
--- a/main.cpp
+++ b/main.cpp
@@ -802,6 +802,8 @@ bool IsTypeDefinition(const CXIdxContainerInfo* container) {
     return false;
 
   switch (container->cursor.kind) {
+  case CXCursor_EnumDecl:
+  case CXCursor_UnionDecl:
   case CXCursor_StructDecl:
   case CXCursor_ClassDecl:
     return true;
@@ -936,6 +938,7 @@ void indexDeclaration(CXClientData client_data, const CXIdxDeclInfo* decl) {
     break;
   }
 
+  case CXIdxEntity_EnumConstant:
   case CXIdxEntity_Field:
   case CXIdxEntity_Variable:
   case CXIdxEntity_CXXStaticVariable:
@@ -1115,6 +1118,8 @@ void indexDeclaration(CXClientData client_data, const CXIdxDeclInfo* decl) {
     break;
   }
 
+  case CXIdxEntity_Enum:
+  case CXIdxEntity_Union:
   case CXIdxEntity_Struct:
   case CXIdxEntity_CXXClass:
   {
@@ -1143,15 +1148,17 @@ void indexDeclaration(CXClientData client_data, const CXIdxDeclInfo* decl) {
 
     // Add type-level inheritance information.
     CXIdxCXXClassDeclInfo const* class_info = clang_index_getCXXClassDeclInfo(decl);
-    for (unsigned int i = 0; i < class_info->numBases; ++i) {
-      const CXIdxBaseClassInfo* base_class = class_info->bases[i];
+    if (class_info) {
+      for (unsigned int i = 0; i < class_info->numBases; ++i) {
+        const CXIdxBaseClassInfo* base_class = class_info->bases[i];
 
-      std::optional<TypeId> parent_type_id = ResolveDeclToType(db, base_class->cursor, true /*is_interesting*/, decl->semanticContainer, decl->lexicalContainer);
-      TypeDef* type_def = db->Resolve(type_id); // type_def ptr could be invalidated by ResolveDeclToType.
-      if (parent_type_id) {
-        TypeDef* parent_type_def = db->Resolve(parent_type_id.value());
-        parent_type_def->derived.push_back(type_id);
-        type_def->parents.push_back(parent_type_id.value());
+        std::optional<TypeId> parent_type_id = ResolveDeclToType(db, base_class->cursor, true /*is_interesting*/, decl->semanticContainer, decl->lexicalContainer);
+        TypeDef* type_def = db->Resolve(type_id); // type_def ptr could be invalidated by ResolveDeclToType.
+        if (parent_type_id) {
+          TypeDef* parent_type_def = db->Resolve(parent_type_id.value());
+          parent_type_def->derived.push_back(type_id);
+          type_def->parents.push_back(parent_type_id.value());
+        }
       }
     }
     break;
@@ -1186,9 +1193,8 @@ void indexEntityReference(CXClientData client_data, const CXIdxEntityRefInfo* re
   ParsingDatabase* db = param->db;
   clang::Cursor cursor(ref->cursor);
 
-  // TODO: Index entity call/ctor creation, like Foo().x = 3
-
   switch (ref->referencedEntity->kind) {
+  case CXIdxEntity_EnumConstant:
   case CXIdxEntity_CXXStaticVariable:
   case CXIdxEntity_Variable:
   case CXIdxEntity_Field:
@@ -1255,6 +1261,8 @@ void indexEntityReference(CXClientData client_data, const CXIdxEntityRefInfo* re
 
   case CXIdxEntity_Typedef:
   case CXIdxEntity_CXXTypeAlias:
+  case CXIdxEntity_Enum:
+  case CXIdxEntity_Union:
   case CXIdxEntity_Struct:
   case CXIdxEntity_CXXClass:
   {
@@ -1431,7 +1439,7 @@ int main(int argc, char** argv) {
 
   for (std::string path : GetFilesInFolder("tests")) {
     //if (path != "tests/declaration_vs_definition/class_member_static.cc") continue;
-    //if (path != "tests/usage/type_usage_typedef_and_using_template.cc") continue;
+    //if (path != "tests/enums/enum_class_decl.cc") continue;
     //if (path != "tests/constructors/constructor.cc") continue;
     //if (path == "tests/constructors/destructor.cc") continue;
     //if (path == "tests/usage/func_usage_call_method.cc") continue;
diff --git a/tests/enums/enum_class_decl.cc b/tests/enums/enum_class_decl.cc
new file mode 100644
index 00000000..91e4274e
--- /dev/null
+++ b/tests/enums/enum_class_decl.cc
@@ -0,0 +1,37 @@
+enum class Foo {
+  A,
+  B = 20
+};
+
+/*
+OUTPUT:
+{
+  "types": [{
+      "id": 0,
+      "usr": "c:@E@Foo",
+      "short_name": "Foo",
+      "qualified_name": "Foo",
+      "definition": "1:1:12",
+      "vars": [0, 1],
+      "all_uses": ["1:1:12"]
+    }],
+  "functions": [],
+  "variables": [{
+      "id": 0,
+      "usr": "c:@E@Foo@A",
+      "short_name": "A",
+      "qualified_name": "Foo::A",
+      "definition": "1:2:3",
+      "declaring_type": 0,
+      "all_uses": ["1:2:3"]
+    }, {
+      "id": 1,
+      "usr": "c:@E@Foo@B",
+      "short_name": "B",
+      "qualified_name": "Foo::B",
+      "definition": "1:3:3",
+      "declaring_type": 0,
+      "all_uses": ["1:3:3"]
+    }]
+}
+*/
\ No newline at end of file
diff --git a/tests/enums/enum_decl.cc b/tests/enums/enum_decl.cc
new file mode 100644
index 00000000..715b0bcc
--- /dev/null
+++ b/tests/enums/enum_decl.cc
@@ -0,0 +1,37 @@
+enum Foo {
+  A,
+  B = 20
+};
+
+/*
+OUTPUT:
+{
+  "types": [{
+      "id": 0,
+      "usr": "c:@E@Foo",
+      "short_name": "Foo",
+      "qualified_name": "Foo",
+      "definition": "1:1:6",
+      "vars": [0, 1],
+      "all_uses": ["1:1:6"]
+    }],
+  "functions": [],
+  "variables": [{
+      "id": 0,
+      "usr": "c:@E@Foo@A",
+      "short_name": "A",
+      "qualified_name": "Foo::A",
+      "definition": "1:2:3",
+      "declaring_type": 0,
+      "all_uses": ["1:2:3"]
+    }, {
+      "id": 1,
+      "usr": "c:@E@Foo@B",
+      "short_name": "B",
+      "qualified_name": "Foo::B",
+      "definition": "1:3:3",
+      "declaring_type": 0,
+      "all_uses": ["1:3:3"]
+    }]
+}
+*/
\ No newline at end of file
diff --git a/tests/enums/enum_inherit.cc b/tests/enums/enum_inherit.cc
new file mode 100644
index 00000000..794c9c75
--- /dev/null
+++ b/tests/enums/enum_inherit.cc
@@ -0,0 +1,37 @@
+enum Foo : int {
+  A,
+  B = 20
+};
+
+/*
+OUTPUT:
+{
+  "types": [{
+      "id": 0,
+      "usr": "c:@E@Foo",
+      "short_name": "Foo",
+      "qualified_name": "Foo",
+      "definition": "1:1:6",
+      "vars": [0, 1],
+      "all_uses": ["1:1:6"]
+    }],
+  "functions": [],
+  "variables": [{
+      "id": 0,
+      "usr": "c:@E@Foo@A",
+      "short_name": "A",
+      "qualified_name": "Foo::A",
+      "definition": "1:2:3",
+      "declaring_type": 0,
+      "all_uses": ["1:2:3"]
+    }, {
+      "id": 1,
+      "usr": "c:@E@Foo@B",
+      "short_name": "B",
+      "qualified_name": "Foo::B",
+      "definition": "1:3:3",
+      "declaring_type": 0,
+      "all_uses": ["1:3:3"]
+    }]
+}
+*/
\ No newline at end of file
diff --git a/tests/enums/enum_usage.cc b/tests/enums/enum_usage.cc
new file mode 100644
index 00000000..b508aeb6
--- /dev/null
+++ b/tests/enums/enum_usage.cc
@@ -0,0 +1,47 @@
+enum class Foo {
+  A,
+  B = 20
+};
+
+Foo x = Foo::A;
+
+/*
+OUTPUT:
+{
+  "types": [{
+      "id": 0,
+      "usr": "c:@E@Foo",
+      "short_name": "Foo",
+      "qualified_name": "Foo",
+      "definition": "1:1:12",
+      "vars": [0, 1],
+      "all_uses": ["1:1:12", "*1:6:1", "1:6:9"]
+    }],
+  "functions": [],
+  "variables": [{
+      "id": 0,
+      "usr": "c:@E@Foo@A",
+      "short_name": "A",
+      "qualified_name": "Foo::A",
+      "definition": "1:2:3",
+      "declaring_type": 0,
+      "all_uses": ["1:2:3", "1:6:14"]
+    }, {
+      "id": 1,
+      "usr": "c:@E@Foo@B",
+      "short_name": "B",
+      "qualified_name": "Foo::B",
+      "definition": "1:3:3",
+      "declaring_type": 0,
+      "all_uses": ["1:3:3"]
+    }, {
+      "id": 2,
+      "usr": "c:@x",
+      "short_name": "x",
+      "qualified_name": "x",
+      "definition": "1:6:5",
+      "variable_type": 0,
+      "all_uses": ["1:6:5"]
+    }]
+}
+*/
\ No newline at end of file
diff --git a/tests/unions/union_decl.cc b/tests/unions/union_decl.cc
new file mode 100644
index 00000000..ca9a8771
--- /dev/null
+++ b/tests/unions/union_decl.cc
@@ -0,0 +1,37 @@
+union Foo {
+  int a;
+  bool b;
+};
+
+/*
+OUTPUT:
+{
+  "types": [{
+      "id": 0,
+      "usr": "c:@U@Foo",
+      "short_name": "Foo",
+      "qualified_name": "Foo",
+      "definition": "1:1:7",
+      "vars": [0, 1],
+      "all_uses": ["1:1:7"]
+    }],
+  "functions": [],
+  "variables": [{
+      "id": 0,
+      "usr": "c:@U@Foo@FI@a",
+      "short_name": "a",
+      "qualified_name": "Foo::a",
+      "definition": "1:2:7",
+      "declaring_type": 0,
+      "all_uses": ["1:2:7"]
+    }, {
+      "id": 1,
+      "usr": "c:@U@Foo@FI@b",
+      "short_name": "b",
+      "qualified_name": "Foo::b",
+      "definition": "1:3:8",
+      "declaring_type": 0,
+      "all_uses": ["1:3:8"]
+    }]
+}
+*/
\ No newline at end of file
diff --git a/tests/unions/union_usage.cc b/tests/unions/union_usage.cc
new file mode 100644
index 00000000..bba5924a
--- /dev/null
+++ b/tests/unions/union_usage.cc
@@ -0,0 +1,58 @@
+union Foo {
+  int a : 5;
+  bool b : 3;
+};
+
+Foo f;
+
+void act(Foo*) {
+  f.a = 3;
+}
+
+/*
+OUTPUT:
+{
+  "types": [{
+      "id": 0,
+      "usr": "c:@U@Foo",
+      "short_name": "Foo",
+      "qualified_name": "Foo",
+      "definition": "1:1:7",
+      "vars": [0, 1],
+      "all_uses": ["1:1:7", "*1:6:1", "*1:8:10"]
+    }],
+  "functions": [{
+      "id": 0,
+      "usr": "c:@F@act#*$@U@Foo#",
+      "short_name": "act",
+      "qualified_name": "act",
+      "definition": "1:8:6",
+      "all_uses": ["1:8:6"]
+    }],
+  "variables": [{
+      "id": 0,
+      "usr": "c:@U@Foo@FI@a",
+      "short_name": "a",
+      "qualified_name": "Foo::a",
+      "definition": "1:2:7",
+      "declaring_type": 0,
+      "all_uses": ["1:2:7", "1:9:5"]
+    }, {
+      "id": 1,
+      "usr": "c:@U@Foo@FI@b",
+      "short_name": "b",
+      "qualified_name": "Foo::b",
+      "definition": "1:3:8",
+      "declaring_type": 0,
+      "all_uses": ["1:3:8"]
+    }, {
+      "id": 2,
+      "usr": "c:@f",
+      "short_name": "f",
+      "qualified_name": "f",
+      "definition": "1:6:5",
+      "variable_type": 0,
+      "all_uses": ["1:6:5", "1:9:3"]
+    }]
+}
+*/
\ No newline at end of file