Implement LWG 3145: file_clock breaks ABI for C++17 implementations.

This patch adds std::chrono::file_clock, but without breaking the
existing ABI for std::filesystem.

llvm-svn: 349883

1 files changed, 35 insertions, 0 deletions

diff --git a/libcxx/test/std/utilities/time/time.clock/time.clock.file/now.pass.cpp b/libcxx/test/std/utilities/time/time.clock/time.clock.file/now.pass.cpp
new file mode 100644
index 00000000000..69dfa918093
--- /dev/null
+++ b/libcxx/test/std/utilities/time/time.clock/time.clock.file/now.pass.cpp
@@ -0,0 +1,35 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
+
+// TODO: Remove this when filesystem gets integrated into the dylib
+// REQUIRES: c++filesystem
+
+// <chrono>
+
+// file_clock
+
+// static time_point now() noexcept;
+
+#include <chrono>
+#include <cassert>
+
+#include "test_macros.h"
+
+int main()
+{
+    typedef std::chrono::file_clock C;
+    ASSERT_NOEXCEPT(C::now());
+
+    C::time_point t1 = C::now();
+    assert(t1.time_since_epoch().count() != 0);
+    assert(C::time_point::min() < t1);
+    assert(C::time_point::max() > t1);
+}