Move compile test to separate source file

test/Jamfile.v2

@@ -226,6 +226,7 @@ run empty_value_test.cpp ;
 run empty_value_size_test.cpp ;
 run empty_value_final_test.cpp ;
 run empty_value_constexpr_test.cpp ;
+compile empty_value_nested_test.cpp ;
 compile-fail empty_value_compile_fail_casting.cpp ;
 
 run quick_exit_test.cpp ;

test/empty_value_nested_test.cpp

@@ -0,0 +1,45 @@
+/*
+Copyright 2024 Braden Ganetsky
+([email protected])
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#include <boost/core/empty_value.hpp>
+
+/*
+Tests workaround for MSVC bug:
+https://developercommunity.visualstudio.com/t/Compiler-bug:-Incorrect-C2247-and-C2248/10690025
+*/
+template<class T>
+struct derived
+    : boost::empty_value<T> {
+    typedef typename boost::empty_value<T>::type type;
+    derived(boost::empty_init_t e)
+        : boost::empty_value<T>(e) { }
+};
+
+struct outer {
+    struct inner_empty { };
+    struct inner_non_empty {
+        inner_non_empty()
+            : value() { }
+        int value;
+    };
+};
+
+void test()
+{
+    const boost::empty_value<outer> x1(boost::empty_init);
+    (void)x1;
+    const boost::empty_value<outer::inner_empty> x2(boost::empty_init);
+    (void)x2;
+    const boost::empty_value<outer::inner_non_empty> x3(boost::empty_init);
+    (void)x3;
+    const derived<outer> x4(boost::empty_init);
+    (void)x4;
+    const derived<outer::inner_empty> x5(boost::empty_init);
+    (void)x5;
+    const derived<outer::inner_non_empty> x6(boost::empty_init);
+    (void)x6;
+}

test/empty_value_test.cpp

@@ -63,40 +63,6 @@ void test_type()
     BOOST_TEST(v2.get().value() == 6);
 }
 
-template <class T>
-struct derived : boost::empty_value<T> {
-    typedef typename boost::empty_value<T>::type type;
-    derived(boost::empty_init_t e) : boost::empty_value<T>(e) {}
-};
-
-struct outer {
-    struct inner_empty {};
-    struct inner_non_empty {
-        inner_non_empty() : value() {}
-        int value;
-    };
-};
-
-void test_derived_compile()
-{
-    // This is testing the workaround to an MSVC bug when T is a nested class.
-    // See https://developercommunity.visualstudio.com/t/Compiler-bug:-Incorrect-C2247-and-C2248/10690025
-
-    const boost::empty_value<outer> x1(boost::empty_init);
-    const boost::empty_value<outer::inner_empty> x2(boost::empty_init);
-    const boost::empty_value<outer::inner_non_empty> x3(boost::empty_init);
-    const derived<outer> x4(boost::empty_init);
-    const derived<outer::inner_empty> x5(boost::empty_init);
-    const derived<outer::inner_non_empty> x6(boost::empty_init);
-
-    (void)x1;
-    (void)x2;
-    (void)x3;
-    (void)x4;
-    (void)x5;
-    (void)x6;
-}
-
 int main()
 {
     test_int();