1 files changed, 38 insertions, 0 deletions
diff --git a/libcxx/test/std/utilities/time/time.hms/time.12/make12.pass.cpp b/libcxx/test/std/utilities/time/time.hms/time.12/make12.pass.cpp
new file mode 100644
index 00000000000..bca956802f9
--- /dev/null
+++ b/libcxx/test/std/utilities/time/time.hms/time.12/make12.pass.cpp
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
+// <chrono>
+
+// constexpr hours make12(const hours& h) noexcept;
+//   Returns: The 12-hour equivalent of h in the range [1h, 12h].
+//     If h is not in the range [0h, 23h], the value returned is unspecified.
+
+#include <chrono>
+#include <cassert>
+
+#include "test_macros.h"
+
+int main(int, char**)
+{
+    using hours = std::chrono::hours;
+    ASSERT_SAME_TYPE(hours, decltype(std::chrono::make12(std::declval<hours>())));
+    ASSERT_NOEXCEPT(                 std::chrono::make12(std::declval<hours>()));
+
+    static_assert( std::chrono::make12(hours( 0)) == hours(12), "");
+    static_assert( std::chrono::make12(hours(11)) == hours(11), "");
+    static_assert( std::chrono::make12(hours(12)) == hours(12), "");
+    static_assert( std::chrono::make12(hours(23)) == hours(11), "");
+    
+    assert( std::chrono::make12(hours(0)) == hours(12));
+    for (int i = 1; i < 13; ++i)
+        assert( std::chrono::make12(hours(i)) == hours(i));
+    for (int i = 13; i < 24; ++i)
+        assert( std::chrono::make12(hours(i)) == hours(i-12));
+
+    return 0;
+}