C++: Self-registering functions using macros for test libraries

self_registering.cpp

// ---- .hpp ----
// Refer to 
// https://blog.rubenwardy.com/2019/02/17/cpp-self-registering-test-macros

#include <functional>

#define Test(name) \
    void test_##name(); \
    static bool test_##name##_registered = TestFactory::Register(#name, &test_##name); \
    void test_##name()

class TestFactory {
public:
    static bool Register(std::string name, std::function<bool()> func);
private:
    static std::map<std::string, std::function<bool()>> Tests;
}

// ---- .cpp ----

std::map<std::string, std::function<bool()>> TestRunner::Tests;

bool TestFactory::Register(std::string name, std::function<bool()> func) {
    auto it = Tests.find(name);
    if (it == Tests.end()) {
        Tests[name] = std::move(func);
        return true;
    }
    return false;
}

Another pretty static registration macro refers to
https://artificial-mind.net/blog/2020/10/17/static-registration-macro.