1 files changed, 45 insertions, 0 deletions
diff --git a/src/catch2/internal/catch_singletons.hpp b/src/catch2/internal/catch_singletons.hpp
new file mode 100644
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+++ b/src/catch2/internal/catch_singletons.hpp
@@ -0,0 +1,45 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+#ifndef CATCH_SINGLETONS_HPP_INCLUDED
+#define CATCH_SINGLETONS_HPP_INCLUDED
+
+namespace Catch {
+
+    struct ISingleton {
+        virtual ~ISingleton(); // = default
+    };
+
+
+    void addSingleton( ISingleton* singleton );
+    void cleanupSingletons();
+
+
+    template<typename SingletonImplT, typename InterfaceT = SingletonImplT, typename MutableInterfaceT = InterfaceT>
+    class Singleton : SingletonImplT, public ISingleton {
+
+        static auto getInternal() -> Singleton* {
+            static Singleton* s_instance = nullptr;
+            if( !s_instance ) {
+                s_instance = new Singleton;
+                addSingleton( s_instance );
+            }
+            return s_instance;
+        }
+
+    public:
+        static auto get() -> InterfaceT const& {
+            return *getInternal();
+        }
+        static auto getMutable() -> MutableInterfaceT& {
+            return *getInternal();
+        }
+    };
+
+} // namespace Catch
+
+#endif // CATCH_SINGLETONS_HPP_INCLUDED