change inheritance to member variable

Author: Robert-Andrzejuk-Infor

include/beman/scope/scope.hpp

@@ -4,6 +4,7 @@
 #define BEMAN_SCOPE_HPP
 
 #include <concepts>
+#include <functional>
 #include <exception>
 
 namespace beman::scope {
@@ -78,7 +79,7 @@ struct ExecuteAlways;
 //=========================================================
 
 template <invocable_return<void> ExitFunc, scope_invoke_checker InvokeChecker = ExecuteAlways>
-class scope_guard : public InvokeChecker {
+class scope_guard {
   public:
     explicit scope_guard(ExitFunc&& exit_func) /*noexcept(see below)*/
         : m_exit_func(std::move(exit_func))    //
@@ -185,17 +186,19 @@ class Releasable<void> {
 };
 
 template <scope_invoke_checker InvokeChecker>
-class Releasable<InvokeChecker> : private InvokeChecker {
+class Releasable<InvokeChecker> {
   public:
     Releasable() = default;
 
     Releasable(InvokeChecker&& invoke_checker) : InvokeChecker(std::move(invoke_checker)) {}
 
-    bool can_invoke() const { return m_can_invoke && static_cast<const InvokeChecker*>(this)->can_invoke(); }
+    bool can_invoke() const { return m_can_invoke && m_invoke_checker.can_invoke(); }
 
     void release() { m_can_invoke = false; }
 
   private:
+    [[no_unique_address]] InvokeChecker m_invoke_checker = {};
+
     bool m_can_invoke = true;
 };
 

tests/beman/scope/scope.test.cpp

@@ -14,9 +14,13 @@ TEST_CASE("scope_guard") {
     SECTION("Constructing") {
 
         auto exit_guard = beman::scope::scope_guard{[] {}, [] { return true; }};
-        // exit_guard.release(); // doesn't compile (as planned)- NOT releasable
+        // vvv doesn't compile (as planned)- NOT releasable
+        // exit_guard.release();
 
-        // auto exit_guard2 = beman::scope::scope_guard{[] {}, [] { return 1; }}; // Doesn't compile, return must be bool
+        REQUIRE(sizeof(decltype(exit_guard)) == 1);
+
+        // vvv Doesn't compile (as planned), return must be bool
+        // auto exit_guard2 = beman::scope::scope_guard{[] {}, [] { return 1; }};
 
         REQUIRE(true);
     }