[libcxx-commits] [libcxx] [libc++][chrono] Fixes (sys|local)_time formatters. (PR #76456)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,175 @@
+//===----------------------------------------------------------------------===//
+//
+// 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-localization
+// UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME
+
+// TODO FMT This test should not require std::to_chars(floating-point)
+// XFAIL: availability-fp_to_chars-missing
+
+// TODO FMT Investigate Windows issues.
+// XFAIL: msvc
+
+// REQUIRES: locale.fr_FR.UTF-8
+// REQUIRES: locale.ja_JP.UTF-8
+
+// <chrono>
+
+// class system_Clock;
+
+// template<class charT, class traits>
+//   basic_ostream<charT, traits>&
+//     operator<<(basic_ostream<charT, traits>& os, const sys_days& dp);
+
+#include <cassert>
+#include <chrono>
+#include <ratio>
+#include <sstream>
+
+#include "make_string.h"
+#include "platform_support.h" // locale name macros
+#include "test_macros.h"
+#include "assert_macros.h"
+#include "concat_macros.h"
+
+#define SV(S) MAKE_STRING_VIEW(CharT, S)
+
+#define TEST_EQUAL(OUT, EXPECTED)                                                                                      \
+  TEST_REQUIRE(OUT == EXPECTED,                                                                                        \
+               TEST_WRITE_CONCATENATED(                                                                                \
+                   "\nExpression      ", #OUT, "\nExpected output ", EXPECTED, "\nActual output   ", OUT, '\n'));
+
+template <class CharT>
+static std::basic_string<CharT> stream_c_locale(const std::chrono::sys_days& dp) {
+  std::basic_stringstream<CharT> sstr;
+  sstr << dp;
+  return sstr.str();
+}
+
+template <class CharT>
+static std::basic_string<CharT> stream_fr_FR_locale(const std::chrono::sys_days& dp) {
+  std::basic_stringstream<CharT> sstr;
+  const std::locale locale(LOCALE_fr_FR_UTF_8);
+  sstr.imbue(locale);
+  sstr << dp;
+  return sstr.str();
+}
+
+template <class CharT>
+static std::basic_string<CharT> stream_ja_JP_locale(const std::chrono::sys_days& dp) {
+  std::basic_stringstream<CharT> sstr;
+  const std::locale locale(LOCALE_ja_JP_UTF_8);
+  sstr.imbue(locale);
+  sstr << dp;
+  return sstr.str();
+}
+
+template <class CharT>
+static void test() {
+  TEST_EQUAL(stream_c_locale<CharT>(std::chrono::sys_days{
+                 std::chrono::year_month_day{std::chrono::year{-32'768}, std::chrono::month{1}, std::chrono::day{1}}}),
+             SV("-32768-01-01 is not a valid date"));
+  TEST_EQUAL(stream_c_locale<CharT>(std::chrono::sys_days{
+                 std::chrono::year_month_day{std::chrono::year{1970}, std::chrono::month{1}, std::chrono::day{1}}}),
+             SV("1970-01-01"));
+  TEST_EQUAL(stream_c_locale<CharT>(std::chrono::sys_days{
+                 std::chrono::year_month_day{std::chrono::year{2000}, std::chrono::month{2}, std::chrono::day{29}}}),
+             SV("2000-02-29"));
+
+#if defined(_AIX)
+  TEST_EQUAL(stream_c_locale<CharT>(std::chrono::sys_days{
+                 std::chrono::year_month_day{std::chrono::year{32'767}, std::chrono::month{12}, std::chrono::day{31}}}),
+             SV("+32767-12-31"));
+#elif defined(_WIN32) // defined(_AIX)
----------------
ldionne wrote:

Nitpick, but I find these `defined (_AIX)` comments kinda confusing since only the first block pertains to `_AIX`.

https://github.com/llvm/llvm-project/pull/76456