Improve local_time test

Author: vitaut

test/chrono-test.cc

@@ -353,36 +353,71 @@ TEST(chrono_test, system_clock_time_point) {
 TEST(chrono_test, local_time) {
   auto time =
       fmt::local_time<std::chrono::seconds>(std::chrono::seconds(290088000));
-  EXPECT_EQ(fmt::format("{:%Y-%m-%d %H:%M:%S}", time), "1979-03-12 12:00:00");
+
   EXPECT_EQ(fmt::format("{}", time), "1979-03-12 12:00:00");
   EXPECT_EQ(fmt::format("{:}", time), "1979-03-12 12:00:00");
 
-  std::vector<std::string> specs = {
-      "%%",  "%n",  "%t",  "%Y",  "%EY", "%y",  "%Oy", "%Ey", "%C",
-      "%EC", "%G",  "%g",  "%b",  "%h",  "%B",  "%m",  "%Om", "%U",
-      "%OU", "%W",  "%OW", "%V",  "%OV", "%j",  "%d",  "%Od", "%e",
-      "%Oe", "%a",  "%A",  "%w",  "%Ow", "%u",  "%Ou", "%H",  "%OH",
-      "%I",  "%OI", "%M",  "%OM", "%S",  "%OS", "%x",  "%Ex", "%X",
-      "%EX", "%D",  "%F",  "%R",  "%T",  "%p"};
-#ifndef _WIN32
-  // Disabled on Windows because these formats are not consistent among
-  // platforms.
-  specs.insert(specs.end(), {"%c", "%Ec", "%r"});
-#elif !FMT_HAS_C99_STRFTIME
-  // Only C89 conversion specifiers when using MSVCRT instead of UCRT
-  specs = {"%%", "%Y", "%y", "%b", "%B", "%m", "%U", "%W", "%j", "%d", "%a",
-           "%A", "%w", "%H", "%I", "%M", "%S", "%x", "%X", "%p"};
-#endif
-  specs.push_back("%Y-%m-%d %H:%M:%S");
-
-  for (const auto& spec : specs) {
-    auto tm = fmt::gmtime(time.time_since_epoch().count());
-    auto sys_output = system_strftime(spec, &tm);
-
-    auto fmt_spec = fmt::format("{{:{}}}", spec);
-    EXPECT_EQ(sys_output, fmt::format(fmt::runtime(fmt_spec), time))
-        << fmt_spec;
-    EXPECT_EQ(sys_output, fmt::format(fmt::runtime(fmt_spec), tm));
+  constexpr struct {
+    const char* format;
+    const char* output;
+  } data[] = {{"{:%%}", "%"},
+              {"{:%n}", "\n"},
+              {"{:%t}", "\t"},
+              {"{:%Y}", "1979"},
+              {"{:%EY}", "1979"},
+              {"{:%y}", "79"},
+              {"{:%Oy}", "79"},
+              {"{:%Ey}", "79"},
+              {"{:%C}", "19"},
+              {"{:%EC}", "19"},
+              {"{:%G}", "1979"},
+              {"{:%g}", "79"},
+              {"{:%b}", "Mar"},
+              {"{:%h}", "Mar"},
+              {"{:%B}", "March"},
+              {"{:%m}", "03"},
+              {"{:%Om}", "03"},
+              {"{:%U}", "10"},
+              {"{:%OU}", "10"},
+              {"{:%W}", "11"},
+              {"{:%OW}", "11"},
+              {"{:%V}", "11"},
+              {"{:%OV}", "11"},
+              {"{:%j}", "071"},
+              {"{:%d}", "12"},
+              {"{:%Od}", "12"},
+              {"{:%e}", "12"},
+              {"{:%Oe}", "12"},
+              {"{:%a}", "Mon"},
+              {"{:%A}", "Monday"},
+              {"{:%w}", "1"},
+              {"{:%Ow}", "1"},
+              {"{:%u}", "1"},
+              {"{:%Ou}", "1"},
+              {"{:%H}", "12"},
+              {"{:%OH}", "12"},
+              {"{:%I}", "12"},
+              {"{:%OI}", "12"},
+              {"{:%M}", "00"},
+              {"{:%OM}", "00"},
+              {"{:%S}", "00"},
+              {"{:%OS}", "00"},
+              {"{:%x}", "03/12/79"},
+              {"{:%Ex}", "03/12/79"},
+              {"{:%X}", "12:00:00"},
+              {"{:%EX}", "12:00:00"},
+              {"{:%D}", "03/12/79"},
+              {"{:%F}", "1979-03-12"},
+              {"{:%R}", "12:00"},
+              {"{:%T}", "12:00:00"},
+              {"{:%p}", "PM"},
+              {"{:%c}", "Mon Mar 12 12:00:00 1979"},
+              {"{:%Ec}", "Mon Mar 12 12:00:00 1979"},
+              {"{:%r}", "12:00:00 PM"},
+              {"{:%Y-%m-%d %H:%M:%S}", "1979-03-12 12:00:00"}};
+
+  for (auto d : data) {
+    EXPECT_EQ(fmt::format(d.format, time), d.output);
   }
 
   EXPECT_THROW_MSG((void)fmt::format(fmt::runtime("{:%z}"), time),