From fc23cfbf4e2e9e29f53214c6159e59c7a5f9a507 Mon Sep 17 00:00:00 2001
From: Dimitrij Mijoski <dmjpp@hotmail.com>
Date: Mon, 8 Aug 2022 22:35:51 +0200
Subject: [PATCH] Fix testsuite on MinGW + MSVCRT

Fixes #2952. The testsuite indirectly called strftime() with conversion
specifiers defined only in C99. In MSVCRT this function conforms only to
C89. Only in the updated UCRT this functon provides the functionality of
C99.
---
 test/chrono-test.cc | 13 ++++++++++++-
 test/xchar-test.cc  |  9 +++++++--
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/test/chrono-test.cc b/test/chrono-test.cc
index 959fb65a..0f2a2498 100644
--- a/test/chrono-test.cc
+++ b/test/chrono-test.cc
@@ -121,6 +121,13 @@ TEST(chrono_test, format_tm) {
       make_tm(2000, 1, 2, 12, 14, 16),    // W52
       make_tm(2000, 1, 3, 12, 14, 16)     // W1
   };
+
+#if defined(__MINGW32__) && !defined(_UCRT)
+  GTEST_SKIP() << "Skip the rest of this test because it relies on strftime() "
+                  "conforming to C99, but on this platform, MINGW + MSVCRT, "
+                  "the function conforms only to C89.";
+#endif
+
   const std::string iso_week_spec = "%Y-%m-%d: %G %g %V";
   for (auto ctm : tm_list) {
     // Calculate tm_yday, tm_wday, etc.
@@ -261,12 +268,16 @@ TEST(chrono_test, time_point) {
       "%Oe", "%a",  "%A",  "%w",  "%Ow", "%u",  "%Ou", "%H",  "%OH",
       "%I",  "%OI", "%M",  "%OM", "%S",  "%OS", "%x",  "%Ex", "%X",
       "%EX", "%D",  "%F",  "%R",  "%T",  "%p",  "%z",  "%Z"};
-  spec_list.push_back("%Y-%m-%d %H:%M:%S");
 #ifndef _WIN32
   // Disabled on Windows because these formats are not consistent among
   // platforms.
   spec_list.insert(spec_list.end(), {"%c", "%Ec", "%r"});
+#elif defined(__MINGW32__) && !defined(_UCRT)
+  // Only C89 conversion specifiers when using MSVCRT instead of UCRT
+  spec_list = {"%%", "%Y", "%y", "%b", "%B", "%m", "%U", "%W", "%j", "%d", "%a",
+               "%A", "%w", "%H", "%I", "%M", "%S", "%x", "%X", "%p", "%Z"};
 #endif
+  spec_list.push_back("%Y-%m-%d %H:%M:%S");
 
   for (const auto& spec : spec_list) {
     auto t = std::chrono::system_clock::to_time_t(t1);
diff --git a/test/xchar-test.cc b/test/xchar-test.cc
index 290f5ffa..fce3e977 100644
--- a/test/xchar-test.cc
+++ b/test/xchar-test.cc
@@ -282,7 +282,7 @@ std::wstring system_wcsftime(const std::wstring& format, const std::tm* timeptr,
 #endif
 }
 
-TEST(chrono_test, time_point) {
+TEST(chrono_test_wchar, time_point) {
   auto t1 = std::chrono::system_clock::now();
 
   std::vector<std::wstring> spec_list = {
@@ -292,12 +292,17 @@ TEST(chrono_test, time_point) {
       L"%Oe", L"%a",  L"%A",  L"%w",  L"%Ow", L"%u",  L"%Ou", L"%H",  L"%OH",
       L"%I",  L"%OI", L"%M",  L"%OM", L"%S",  L"%OS", L"%x",  L"%Ex", L"%X",
       L"%EX", L"%D",  L"%F",  L"%R",  L"%T",  L"%p",  L"%z",  L"%Z"};
-  spec_list.push_back(L"%Y-%m-%d %H:%M:%S");
 #ifndef _WIN32
   // Disabled on Windows, because these formats is not consistent among
   // platforms.
   spec_list.insert(spec_list.end(), {L"%c", L"%Ec", L"%r"});
+#elif defined(__MINGW32__) && !defined(_UCRT)
+  // Only C89 conversion specifiers when using MSVCRT instead of UCRT
+  spec_list = {L"%%", L"%Y", L"%y", L"%b", L"%B", L"%m", L"%U",
+               L"%W", L"%j", L"%d", L"%a", L"%A", L"%w", L"%H",
+               L"%I", L"%M", L"%S", L"%x", L"%X", L"%p", L"%Z"};
 #endif
+  spec_list.push_back(L"%Y-%m-%d %H:%M:%S");
 
   for (const auto& spec : spec_list) {
     auto t = std::chrono::system_clock::to_time_t(t1);