tests: Fixed unit test compiling

include/views/view_diff.hpp

@@ -0,0 +1,25 @@
+#pragma once
+
+#include <hex.hpp>
+
+#include <imgui.h>
+#include <hex/views/view.hpp>
+
+#include <array>
+#include <string>
+
+namespace hex {
+
+    namespace prv { class Provider; }
+
+    class ViewTools : public View {
+    public:
+        ViewTools();
+        ~ViewTools() override;
+
+        void drawContent() override;
+        void drawMenu() override;
+
+    };
+
+}