Add test for type properties of std::reference_wrapper

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@221224 91177308-0d34-0410-b5e6-96231b3b80d8

test/utilities/function.objects/refwrap/type_properties.pass.cpp

@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <functional>
+
+// reference_wrapper
+
+// Test that reference wrapper meets the requirements of TriviallyCopyable,
+// CopyConstructible and CopyAssignable.
+
+#include <functional>
+#include <type_traits>
+
+int main()
+{
+    typedef std::reference_wrapper<int> T;
+    static_assert(std::is_copy_constructible<T>::value, "");
+    static_assert(std::is_copy_assignable<T>::value, "");
+    // Extension up for standardization: See N4151.
+    static_assert(std::is_trivially_copyable<T>::value, "");
+}