From b135f1c01449f6f41be3933437797e768b54295a Mon Sep 17 00:00:00 2001
From: Victor Zverovich <viz@fb.com>
Date: Thu, 9 Jun 2022 16:57:52 -0700
Subject: [PATCH] Refactor handling of argument types

---
 include/fmt/compile.h |  4 ++--
 include/fmt/core.h    | 22 ++++++----------------
 test/core-test.cc     |  4 ++--
 3 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/include/fmt/compile.h b/include/fmt/compile.h
index 30cb0664..c09dd6f2 100644
--- a/include/fmt/compile.h
+++ b/include/fmt/compile.h
@@ -337,8 +337,8 @@ template <typename T, typename Char>
 constexpr parse_specs_result<T, Char> parse_specs(basic_string_view<Char> str,
                                                   size_t pos, int next_arg_id) {
   str.remove_prefix(pos);
-  auto ctx =
-      compile_parse_context<Char>(str, format_arg_types<10>(), {}, next_arg_id);
+  auto ctx = compile_parse_context<Char>(str, max_value<int>(), nullptr, {},
+                                         next_arg_id);
   auto f = formatter<T, Char>();
   auto end = f.parse(ctx);
   return {f, pos + fmt::detail::to_unsigned(end - str.data()) + 1,
diff --git a/include/fmt/core.h b/include/fmt/core.h
index 6ca9da27..43335a47 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -597,15 +597,6 @@ constexpr bool is_arithmetic_type(type t) {
   return t > type::none_type && t <= type::last_numeric_type;
 }
 
-template <size_t NUM_ARGS> struct format_arg_types {
-  type types[NUM_ARGS > 0 ? NUM_ARGS : 1];
-};
-
-template <typename... T>
-constexpr format_arg_types<sizeof...(T)> make_format_arg_types() {
-  return {type_constant<T, char>::value...};
-}
-
 FMT_NORETURN FMT_API void throw_format_error(const char* message);
 
 struct error_handler {
@@ -713,13 +704,10 @@ class compile_parse_context
   using base = basic_format_parse_context<Char, ErrorHandler>;
 
  public:
-  template <size_t NUM_ARGS>
   explicit FMT_CONSTEXPR compile_parse_context(
-      basic_string_view<Char> format_str, const format_arg_types<NUM_ARGS>& t,
+      basic_string_view<Char> format_str, int num_args, const type* types,
       ErrorHandler eh = {}, int next_arg_id = 0)
-      : base(format_str, eh, next_arg_id),
-        num_args_(NUM_ARGS),
-        types_(t.types) {}
+      : base(format_str, eh, next_arg_id), num_args_(num_args), types_(types) {}
 
   constexpr int num_args() const { return num_args_; }
 
@@ -2900,12 +2888,14 @@ class format_string_checker {
 
   parse_context_type context_;
   parse_func parse_funcs_[num_args > 0 ? num_args : 1];
+  type types_[num_args > 0 ? num_args : 1];
 
  public:
   explicit FMT_CONSTEXPR format_string_checker(
       basic_string_view<Char> format_str, ErrorHandler eh)
-      : context_(format_str, make_format_arg_types<Args...>(), eh),
-        parse_funcs_{&parse_format_specs<Args, parse_context_type>...} {}
+      : context_(format_str, num_args, types_, eh),
+        parse_funcs_{&parse_format_specs<Args, parse_context_type>...},
+        types_{type_constant<Args, char>::value...} {}
 
   FMT_CONSTEXPR void on_text(const Char*, const Char*) {}
 
diff --git a/test/core-test.cc b/test/core-test.cc
index c7f07273..ce0816c6 100644
--- a/test/core-test.cc
+++ b/test/core-test.cc
@@ -385,11 +385,11 @@ VISIT_TYPE(unsigned long, unsigned long long);
 
 template <typename T> class numeric_arg_test : public testing::Test {};
 
-using types =
+using test_types =
     testing::Types<bool, signed char, unsigned char, short, unsigned short, int,
                    unsigned, long, unsigned long, long long, unsigned long long,
                    float, double, long double>;
-TYPED_TEST_SUITE(numeric_arg_test, types);
+TYPED_TEST_SUITE(numeric_arg_test, test_types);
 
 template <typename T, fmt::enable_if_t<std::is_integral<T>::value, int> = 0>
 T test_value() {