1 files changed, 77 insertions, 0 deletions
diff --git a/libcxx/test/std/time/time.zone/time.zone.db/time.zone.db.access/current_zone.pass.cpp b/libcxx/test/std/time/time.zone/time.zone.db/time.zone.db.access/current_zone.pass.cpp
new file mode 100644
index 000000000000..d85c8ba52622
--- /dev/null
+++ b/libcxx/test/std/time/time.zone/time.zone.db/time.zone.db.access/current_zone.pass.cpp
@@ -0,0 +1,77 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17
+// UNSUPPORTED: no-filesystem, no-localization, no-tzdb
+
+// XFAIL: libcpp-has-no-incomplete-tzdb
+// XFAIL: availability-tzdb-missing
+
+// <chrono>
+
+// const time_zone* current_zone();
+
+#include <cassert>
+#include <chrono>
+#include <string_view>
+#include <stdlib.h>
+
+#include "test_macros.h"
+#include "assert_macros.h"
+#include "concat_macros.h"
+
+#ifdef _WIN32
+static void set_tz(std::string zone) {
+  // Note Windows does not have setenv, only putenv
+  // https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/putenv-s-wputenv-s?view=msvc-170
+  // Unlike POSIX it does not mention the string of putenv becomes part
+  // of the environment.
+
+  int status = _putenv_s("TZ", zone.c_str(), 1);
+  assert(status == 0);
+}
+
+#else
+static void set_tz(const std::string& zone) {
+  int status = setenv("TZ", zone.c_str(), 1);
+  assert(status == 0);
+}
+#endif
+
+static void test_zone(const std::string& zone) {
+  set_tz(zone);
+  const std::chrono::time_zone* tz = std::chrono::current_zone();
+  assert(tz);
+  assert(tz->name() == zone);
+}
+
+static void test_link(const std::string& link, std::string_view zone) {
+  set_tz(link);
+  const std::chrono::time_zone* tz = std::chrono::current_zone();
+  assert(tz);
+  assert(tz->name() == zone);
+}
+
+int main(int, const char**) {
+  const std::chrono::time_zone* tz = std::chrono::current_zone();
+  // Returns a valid time zone, the value depends on the OS settings.
+  assert(tz);
+  // setting the environment to an invalid value returns the value of
+  // the OS setting.
+  set_tz("This is not a time zone");
+  assert(tz == std::chrono::current_zone());
+
+  const std::chrono::tzdb& db = std::chrono::get_tzdb();
+  for (const auto& zone : db.zones)
+    test_zone(std::string{zone.name()});
+
+  for (const auto& link : db.links)
+    test_link(std::string{link.name()}, link.target());
+
+  return 0;
+}