From f187274d3637403e1391deb69233b34b5e345d37 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <viz@fb.com>
Date: Fri, 2 Sep 2022 13:45:23 -0700
Subject: [PATCH] Add loc_value

---
 include/fmt/format-inl.h |  2 +-
 include/fmt/format.h     | 49 +++++++++++++++++++++++-----------------
 test/format-test.cc      | 23 +++++++++++++++++++
 test/xchar-test.cc       | 16 -------------
 4 files changed, 52 insertions(+), 38 deletions(-)

diff --git a/include/fmt/format-inl.h b/include/fmt/format-inl.h
index 80b44a42..6fbdb52a 100644
--- a/include/fmt/format-inl.h
+++ b/include/fmt/format-inl.h
@@ -118,7 +118,7 @@ template <typename Char> FMT_FUNC Char decimal_point_impl(locale_ref) {
 }
 #endif
 
-FMT_FUNC auto write_int(appender out, unsigned long long value,
+FMT_FUNC auto write_int(appender out, loc_value value,
                         const format_specs& specs, locale_ref loc) -> bool {
 #ifndef FMT_STATIC_THOUSANDS_SEPARATOR
   auto locale = loc.get<std::locale>();
diff --git a/include/fmt/format.h b/include/fmt/format.h
index a792f31d..a1b98c7f 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -985,6 +985,29 @@ constexpr auto compile_string_to_view(detail::std_string_view<Char> s)
 }
 }  // namespace detail_exported
 
+// A value to localize.
+struct loc_value {
+  union {
+    unsigned long long ulong_long_value;
+  };
+};
+
+// A locale facet that formats numeric values in UTF-8.
+// It is parameterized on the locale to avoid heavy <locale> include.
+template <typename Locale> class num_format_facet : public Locale::facet {
+ public:
+  static FMT_API typename Locale::id id;
+
+  void put(appender out, loc_value val, const format_specs& specs,
+           Locale& loc) const {
+    do_put(out, val, specs, loc);
+  }
+
+ protected:
+  virtual void do_put(appender out, loc_value val, const format_specs& specs,
+                      Locale& loc) const = 0;
+};
+
 FMT_BEGIN_DETAIL_NAMESPACE
 
 template <typename T> struct is_integral : std::is_integral<T> {};
@@ -2014,11 +2037,11 @@ auto write_int(OutputIt out, UInt value, unsigned prefix,
       });
 }
 
-FMT_API auto write_int(appender out, unsigned long long value,
-                       const format_specs& specs, locale_ref loc) -> bool;
+FMT_API auto write_int(appender out, loc_value value, const format_specs& specs,
+                       locale_ref loc) -> bool;
 template <typename OutputIt, typename Char>
-inline auto write_int(OutputIt, unsigned long long,
-                      const basic_format_specs<Char>&, locale_ref) -> bool {
+inline auto write_int(OutputIt, loc_value, const basic_format_specs<Char>&,
+                      locale_ref) -> bool {
   return false;
 }
 
@@ -2028,7 +2051,7 @@ auto write_int(OutputIt& out, UInt value, unsigned prefix,
   auto result = false;
   auto buf = memory_buffer();
   if (sizeof(value) <= sizeof(unsigned long long))
-    result = write_int(appender(buf), static_cast<unsigned long long>(value),
+    result = write_int(appender(buf), {static_cast<unsigned long long>(value)},
                        specs, loc);
   if (!result) {
     auto grouping = digit_grouping<Char>(loc);
@@ -4176,22 +4199,6 @@ extern template FMT_API auto decimal_point_impl(locale_ref) -> wchar_t;
 
 FMT_END_DETAIL_NAMESPACE
 
-// A locale facet that formats numeric values in UTF-8.
-// It is parameterized on the locale to avoid heavy <locale> include.
-template <typename Locale> class num_format_facet : public Locale::facet {
- public:
-  static FMT_API typename Locale::id id;
-
-  void put(appender out, unsigned long long val, const format_specs& specs,
-           Locale& loc) const {
-    do_put(out, val, specs, loc);
-  }
-
- protected:
-  virtual void do_put(appender out, unsigned long long val,
-                      const format_specs& specs, Locale& loc) const = 0;
-};
-
 #if FMT_USE_USER_DEFINED_LITERALS
 inline namespace literals {
 /**
diff --git a/test/format-test.cc b/test/format-test.cc
index 9d318470..b028aefd 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -2311,3 +2311,26 @@ TEST(format_int_test, format_int) {
   os << max_value<int64_t>();
   EXPECT_EQ(os.str(), fmt::format_int(max_value<int64_t>()).str());
 }
+
+#ifdef FMT_STATIC_THOUSANDS_SEPARATOR
+
+#  include <locale>
+
+class num_format : public fmt::num_format_facet<std::locale> {
+ protected:
+  void do_put(fmt::appender out, fmt::loc_value, const fmt::format_specs&,
+              std::locale&) const override;
+};
+
+void num_format::do_put(fmt::appender out, fmt::loc_value value,
+                        const fmt::format_specs&, std::locale&) const {
+  fmt::format_to(out, "[{}]", value.ulong_long_value);
+}
+
+TEST(format_test, num_format) {
+  auto loc = std::locale(std::locale(), new num_format());
+  EXPECT_EQ(fmt::format(loc, "{:L}", 42), "[42]");
+  EXPECT_EQ(fmt::format(loc, "{:L}", -42), "[-42]");
+}
+
+#endif  // FMT_STATIC_THOUSANDS_SEPARATOR
diff --git a/test/xchar-test.cc b/test/xchar-test.cc
index 91300da1..3eec7384 100644
--- a/test/xchar-test.cc
+++ b/test/xchar-test.cc
@@ -520,20 +520,4 @@ TEST(locale_test, sign) {
   EXPECT_EQ(fmt::format(std::locale(), L"{:L}", -50), L"-50");
 }
 
-class num_format : public fmt::num_format_facet<std::locale> {
- protected:
-  void do_put(fmt::appender out, unsigned long long, const fmt::format_specs&,
-              std::locale&) const override;
-};
-
-void num_format::do_put(fmt::appender out, unsigned long long value,
-                        const fmt::format_specs&, std::locale&) const {
-  fmt::format_to(out, "[{}]", value);
-}
-
-TEST(locale_test, num_format) {
-  auto loc = std::locale(std::locale(), new num_format());
-  EXPECT_EQ(fmt::format(loc, "{:L}", 42), "[42]");
-}
-
 #endif  // FMT_STATIC_THOUSANDS_SEPARATOR