From 5750f9d0f4ce33a82850bfba6a8365b5186199ee Mon Sep 17 00:00:00 2001
From: Victor Zverovich <victor.zverovich@gmail.com>
Date: Sat, 7 Nov 2026 07:55:27 -0800
Subject: [PATCH] Reuse size_padding for localized integers and simplify the
 test

Both integer writers now compute zero padding the same way.
---
 include/fmt/format.h | 56 ++++++++++++++++++++------------------------
 test/format-test.cc  |  6 -----
 2 files changed, 25 insertions(+), 37 deletions(-)

diff --git a/include/fmt/format.h b/include/fmt/format.h
index 1bf3bebe..339e154e 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -2207,6 +2207,27 @@ FMT_CONSTEXPR auto write_int_chr(OutputIt out, UInt abs_value, bool negative,
   return write_char<Char>(out, static_cast<Char>(abs_value), specs);
 }
 
+// Size and padding computation separate from write_int to avoid template bloat.
+struct size_padding {
+  unsigned size;
+  unsigned padding;
+
+  FMT_CONSTEXPR size_padding(int num_digits, unsigned prefix,
+                             const format_specs& specs)
+      : size((prefix >> 24) + to_unsigned(num_digits)), padding(0) {
+    if (specs.align() == align::numeric) {
+      auto width = to_unsigned(specs.width);
+      if (width > size) {
+        padding = width - size;
+        size = width;
+      }
+    } else if (specs.precision > num_digits) {
+      size = (prefix >> 24) + to_unsigned(specs.precision);
+      padding = to_unsigned(specs.precision - num_digits);
+    }
+  }
+};
+
 // Writes a decimal integer with digit grouping.
 template <typename OutputIt, typename UInt, typename Char>
 auto write_int(OutputIt out, UInt value, unsigned prefix,
@@ -2246,19 +2267,13 @@ auto write_int(OutputIt out, UInt value, unsigned prefix,
     return write_int_chr<Char>(out, value, (prefix & 0xff) == '-', specs);
   }
 
-  unsigned size = (prefix != 0 ? prefix >> 24 : 0) + to_unsigned(num_digits) +
-                  to_unsigned(grouping.count_separators(num_digits));
-  unsigned padding = 0;
-  if (specs.align() == align::numeric) {
-    auto width = to_unsigned(specs.width);
-    if (width > size) padding = width - size;
-    size += padding;
-  }
+  auto sp = size_padding(num_digits + grouping.count_separators(num_digits),
+                         prefix, specs);
   return write_padded<Char, align::right>(
-      out, specs, size, size, [&](reserve_iterator<OutputIt> it) {
+      out, specs, sp.size, [&](reserve_iterator<OutputIt> it) {
         for (unsigned p = prefix & 0xffffff; p != 0; p >>= 8)
           *it++ = static_cast<Char>(p & 0xff);
-        it = detail::fill_n(it, padding, static_cast<Char>('0'));
+        it = detail::fill_n(it, sp.padding, static_cast<Char>('0'));
         return grouping.apply(it, string_view(buffer.data(), buffer.size()));
       });
 }
@@ -2317,27 +2332,6 @@ template <typename Char = char> struct loc_writer {
   }
 };
 
-// Size and padding computation separate from write_int to avoid template bloat.
-struct size_padding {
-  unsigned size;
-  unsigned padding;
-
-  FMT_CONSTEXPR size_padding(int num_digits, unsigned prefix,
-                             const format_specs& specs)
-      : size((prefix >> 24) + to_unsigned(num_digits)), padding(0) {
-    if (specs.align() == align::numeric) {
-      auto width = to_unsigned(specs.width);
-      if (width > size) {
-        padding = width - size;
-        size = width;
-      }
-    } else if (specs.precision > num_digits) {
-      size = (prefix >> 24) + to_unsigned(specs.precision);
-      padding = to_unsigned(specs.precision - num_digits);
-    }
-  }
-};
-
 template <typename Char, typename OutputIt, typename T>
 FMT_CONSTEXPR FMT_INLINE auto write_int(OutputIt out, write_int_arg<T> arg,
                                         const format_specs& specs) -> OutputIt {
diff --git a/test/format-test.cc b/test/format-test.cc
index 6a403967..134d6382 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -2694,17 +2694,11 @@ TEST(format_test, format_locale) {
 TEST(format_test, format_int_locale_zero_padding) {
   auto loc = std::locale::classic();
   EXPECT_EQ(fmt::format(loc, "{:08L}", -12), "-0000012");
-  EXPECT_EQ(fmt::format(loc, "{:+08L}", 12), "+0000012");
-  EXPECT_EQ(fmt::format(loc, "{: 08L}", 12), " 0000012");
-  EXPECT_EQ(fmt::format(loc, "{:08L}", 12), "00000012");
   EXPECT_EQ(fmt::format(loc, "{:02L}", -12), "-12");
-  EXPECT_EQ(fmt::format(loc, "{:>08L}", -12), "     -12");
   EXPECT_EQ(fmt::format(loc, "{:0>8L}", -12), "00000-12");
   loc = std::locale(loc, new fmt::format_facet<std::locale>(","));
   EXPECT_EQ(fmt::format(loc, "{:08L}", -1234), "-001,234");
   EXPECT_EQ(fmt::format(loc, "{:#010Lx}", -0x1234), "-0x001,234");
-  EXPECT_EQ(fmt::format(loc, "{:#010Lb}", -10), "-0b001,010");
-  EXPECT_EQ(fmt::format(loc, "{:#08Lo}", -01234), "-001,234");
 }
 
 #endif  // FMT_USE_LOCALE