From 2039dce75fff60d88f2b9bfae521b32aad586190 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <victor.zverovich@gmail.com>
Date: Sun, 6 Jun 2021 17:35:40 -0700
Subject: [PATCH] Detect consteval

---
 include/fmt/core.h  | 20 ++++++++++++--------
 test/format-test.cc |  9 ---------
 test/printf-test.cc | 28 ----------------------------
 3 files changed, 12 insertions(+), 45 deletions(-)

diff --git a/include/fmt/core.h b/include/fmt/core.h
index a15a80b6..bf95038d 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -284,8 +284,16 @@
 #  define FMT_UNICODE !FMT_MSC_VER
 #endif
 
-#ifndef FMT_COMPILE_TIME_CHECKS
-#  define FMT_COMPILE_TIME_CHECKS 0
+#ifndef FMT_CONSTEVAL
+#  if ((FMT_GCC_VERSION >= 1000 || FMT_CLANG_VERSION >= 1101) && \
+       __cplusplus > 201703L) ||                                 \
+      (defined(__cpp_consteval) &&                               \
+       !FMT_MSC_VER)  // consteval is broken in MSVC.
+#    define FMT_CONSTEVAL consteval
+#    define FMT_HAS_CONSTEVAL
+#  else
+#    define FMT_CONSTEVAL
+#  endif
 #endif
 
 #ifndef FMT_USE_NONTYPE_TEMPLATE_PARAMETERS
@@ -2813,17 +2821,13 @@ template <typename Char, typename... Args> class basic_format_string {
   template <typename S,
             FMT_ENABLE_IF(
                 std::is_convertible<const S&, basic_string_view<Char>>::value)>
-#if FMT_COMPILE_TIME_CHECKS
-  consteval
-#endif
-      basic_format_string(const S& s)
-      : str_(s) {
+  FMT_CONSTEVAL basic_format_string(const S& s) : str_(s) {
     static_assert(
         detail::count<
             (std::is_base_of<detail::view, remove_reference_t<Args>>::value &&
              std::is_reference<Args>::value)...>() == 0,
         "passing views as lvalues is disallowed");
-#if FMT_COMPILE_TIME_CHECKS
+#ifdef FMT_HAS_CONSTEVAL
     if constexpr (detail::count_named_args<Args...>() == 0) {
       using checker = detail::format_string_checker<Char, detail::error_handler,
                                                     remove_cvref_t<Args>...>;
diff --git a/test/format-test.cc b/test/format-test.cc
index 28505304..19597a12 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -2059,15 +2059,6 @@ TEST(format_test, vformat_to) {
   EXPECT_EQ("42", s);
 }
 
-template <typename T> static std::string fmt_to_string(const T& t) {
-  return fmt::format(FMT_STRING("{}"), t);
-}
-
-TEST(format_test, fmt_string_in_template) {
-  EXPECT_EQ(fmt_to_string(1), "1");
-  EXPECT_EQ(fmt_to_string(0), "0");
-}
-
 #endif  // FMT_USE_CONSTEXPR
 
 TEST(format_test, char_traits_is_not_ambiguous) {
diff --git a/test/printf-test.cc b/test/printf-test.cc
index e1b606a1..295c2f42 100644
--- a/test/printf-test.cc
+++ b/test/printf-test.cc
@@ -52,34 +52,6 @@ std::wstring test_sprintf(fmt::basic_string_view<wchar_t> format,
       << "format: " << format;                          \
   EXPECT_EQ(expected_output, fmt::sprintf(make_positional(format), arg))
 
-template <typename T> struct value_extractor {
-  T operator()(T value) { return value; }
-
-  template <typename U> FMT_NORETURN T operator()(U) {
-    throw std::runtime_error(fmt::format("invalid type {}", typeid(U).name()));
-  }
-
-#if FMT_USE_INT128
-  // Apple Clang does not define typeid for __int128_t and __uint128_t.
-  FMT_NORETURN T operator()(fmt::detail::int128_t) {
-    throw std::runtime_error("invalid type __int128_t");
-  }
-
-  FMT_NORETURN T operator()(fmt::detail::uint128_t) {
-    throw std::runtime_error("invalid type __uint128_t");
-  }
-#endif
-};
-
-TEST(printf_test, arg_converter) {
-  long long value = max_value<long long>();
-  auto arg = fmt::detail::make_arg<fmt::format_context>(value);
-  fmt::visit_format_arg(
-      fmt::detail::arg_converter<long long, fmt::format_context>(arg, 'd'),
-      arg);
-  EXPECT_EQ(value, fmt::visit_format_arg(value_extractor<long long>(), arg));
-}
-
 TEST(printf_test, no_args) {
   EXPECT_EQ("test", test_sprintf("test"));
   EXPECT_EQ(L"test", fmt::sprintf(L"test"));