fmt: add upstream patch

Formula/f/fmt.rb

@@ -4,6 +4,7 @@ class Fmt < Formula
   url "https://github.com/fmtlib/fmt/archive/refs/tags/10.2.1.tar.gz"
   sha256 "1250e4cc58bf06ee631567523f48848dc4596133e163f02615c97f78bab6c811"
   license "MIT"
+  revision 1
   head "https://github.com/fmtlib/fmt.git", branch: "master"
 
   bottle do
@@ -18,6 +19,11 @@ class Fmt < Formula
 
   depends_on "cmake" => :build
 
+  # Fix handling of static separator; cherry-picked from:
+  # https://github.com/fmtlib/fmt/commit/44c3fe1ebb466ab5c296e1a1a6991c7c7b51b72e
+  # Remove when included in a release.
+  patch :DATA
+
   def install
     system "cmake", "-S", ".", "-B", "build", "-DBUILD_SHARED_LIBS=TRUE", *std_cmake_args
     system "cmake", "--build", "build"
@@ -48,3 +54,30 @@ def install
     assert_equal "The answer is 42", shell_output("./test")
   end
 end
+
+__END__
+diff --git a/include/fmt/format-inl.h b/include/fmt/format-inl.h
+index 9fc87ecf2027df0346935e7666ea80ec70e65575..872aa9802df1ffa8572a2f0d29f58bdb2b171a1a 100644
+--- a/include/fmt/format-inl.h
++++ b/include/fmt/format-inl.h
+@@ -110,7 +110,11 @@ template <typename Char> FMT_FUNC Char decimal_point_impl(locale_ref) {
+
+ FMT_FUNC auto write_loc(appender out, loc_value value,
+                         const format_specs<>& specs, locale_ref loc) -> bool {
+-#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
++#ifdef FMT_STATIC_THOUSANDS_SEPARATOR
++  value.visit(loc_writer<>{
++      out, specs, std::string(1, FMT_STATIC_THOUSANDS_SEPARATOR), "\3", "."});
++  return true;
++#else
+   auto locale = loc.get<std::locale>();
+   // We cannot use the num_put<char> facet because it may produce output in
+   // a wrong encoding.
+@@ -119,7 +123,6 @@ FMT_FUNC auto write_loc(appender out, loc_value value,
+     return std::use_facet<facet>(locale).put(out, value, specs);
+   return facet(locale).put(out, value, specs);
+ #endif
+-  return false;
+ }
+ }  // namespace detail
+