From 106dc8fd642148828d63c69e9b534ccafd80f8d4 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <viz@meta.com>
Date: Wed, 4 Sep 2024 16:23:51 -0700
Subject: [PATCH] Reduce usage of type_identity

---
 include/fmt/base.h    | 18 ++++++------------
 include/fmt/format.h  |  5 +++++
 include/fmt/ostream.h |  4 ++--
 3 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/include/fmt/base.h b/include/fmt/base.h
index a9a3a96b..9d8c54a9 100644
--- a/include/fmt/base.h
+++ b/include/fmt/base.h
@@ -334,10 +334,6 @@ template <typename T>
 using remove_const_t = typename std::remove_const<T>::type;
 template <typename T>
 using remove_cvref_t = typename std::remove_cv<remove_reference_t<T>>::type;
-template <typename T> struct type_identity {
-  using type = T;
-};
-template <typename T> using type_identity_t = typename type_identity<T>::type;
 template <typename T>
 using make_unsigned_t = typename std::make_unsigned<T>::type;
 template <typename T>
@@ -449,9 +445,7 @@ FMT_CONSTEXPR auto to_unsigned(Int value) -> make_unsigned_t<Int> {
 }
 
 template <typename Char>
-using unsigned_char = typename conditional_t<std::is_integral<Char>::value,
-                                             std::make_unsigned<Char>,
-                                             type_identity<unsigned>>::type;
+using unsigned_char = conditional_t<sizeof(Char) == 1, unsigned char, unsigned>;
 
 // A heuristic to detect std::string and std::[experimental::]string_view.
 // It is mainly used to avoid dependency on <[experimental/]string_view>.
@@ -2176,6 +2170,11 @@ auto get_iterator(buffer<T>&, OutputIt out) -> OutputIt {
   return out;
 }
 
+// This type is intentionally undefined, only used for errors.
+template <typename T, typename Char> struct type_is_unformattable_for;
+
+struct custom_tag {};
+
 template <typename Char> struct string_value {
   const Char* data;
   size_t size;
@@ -2192,11 +2191,6 @@ template <typename Context> struct custom_value {
   void (*format)(void* arg, parse_context<char_type>& parse_ctx, Context& ctx);
 };
 
-// This type is intentionally undefined, only used for errors.
-template <typename T, typename Char> struct type_is_unformattable_for;
-
-struct custom_tag {};
-
 // A formatting argument value.
 template <typename Context> class value {
  public:
diff --git a/include/fmt/format.h b/include/fmt/format.h
index 6117ef45..061cb129 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -275,6 +275,11 @@ template <typename Char, typename Traits, typename Allocator>
 struct is_contiguous<std::basic_string<Char, Traits, Allocator>>
     : std::true_type {};
 
+template <typename T> struct type_identity {
+  using type = T;
+};
+template <typename T> using type_identity_t = typename type_identity<T>::type;
+
 namespace detail {
 
 FMT_CONSTEXPR inline void abort_fuzzing_if(bool condition) {
diff --git a/include/fmt/ostream.h b/include/fmt/ostream.h
index 2102f910..b215af28 100644
--- a/include/fmt/ostream.h
+++ b/include/fmt/ostream.h
@@ -161,10 +161,10 @@ inline void vprint_directly(std::ostream& os, string_view format_str,
 
 FMT_EXPORT template <typename Char>
 void vprint(std::basic_ostream<Char>& os,
-            basic_string_view<type_identity_t<Char>> format_str,
+            basic_string_view<type_identity_t<Char>> fmt,
             typename detail::vformat_args<Char>::type args) {
   auto buffer = basic_memory_buffer<Char>();
-  detail::vformat_to(buffer, format_str, args);
+  detail::vformat_to(buffer, fmt, args);
   if (detail::write_ostream_unicode(os, {buffer.data(), buffer.size()})) return;
   detail::write_buffer(os, buffer);
 }