Implement P0426: Constexpr for std::char_traits

llvm-svn: 291741

1 files changed, 16 insertions, 0 deletions

diff --git a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp
index 7dcf08c2e76..7a317f0d66d 100644
--- a/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp
+++ b/libcxx/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.wchar.t/assign2.pass.cpp
@@ -12,13 +12,29 @@
 // template<> struct char_traits<wchar_t>
 
 // static void assign(char_type& c1, const char_type& c2);
+// constexpr in C++17
 
 #include <string>
 #include <cassert>
 
+#include "test_macros.h"
+
+#if TEST_STD_VER > 14
+constexpr bool test_constexpr()
+{
+    wchar_t c = L'1';
+    std::char_traits<wchar_t>::assign(c, L'a');
+    return c == L'a';
+}
+#endif
+
 int main()
 {
     wchar_t c = L'\0';
     std::char_traits<wchar_t>::assign(c, L'a');
     assert(c == L'a');
+
+#if TEST_STD_VER > 14
+    static_assert(test_constexpr(), "" );
+#endif
 }