More locale support

include/fmt/locale.h

@@ -34,6 +34,13 @@ std::basic_string<Char> vformat(
 }
 }
 
+template <typename S, typename Char = FMT_CHAR(S)>
+inline std::basic_string<Char> vformat(
+    const std::locale &loc, const S &format_str,
+    basic_format_args<typename buffer_context<Char>::type> args) {
+  return internal::vformat(loc, to_string_view(format_str), args);
+}
+
 template <typename S, typename... Args>
 inline std::basic_string<FMT_CHAR(S)> format(
     const std::locale &loc, const S &format_str, const Args &... args) {
@@ -42,6 +49,29 @@ inline std::basic_string<FMT_CHAR(S)> format(
     *internal::checked_args<S, Args...>(format_str, args...));
 }
 
+template <typename String, typename OutputIt, typename... Args>
+inline typename std::enable_if<internal::is_output_iterator<OutputIt>::value,
+                               OutputIt>::type
+    vformat_to(OutputIt out, const std::locale &loc, const String &format_str,
+               typename format_args_t<OutputIt, FMT_CHAR(String)>::type args) {
+  typedef output_range<OutputIt, FMT_CHAR(String)> range;
+  return vformat_to<arg_formatter<range>>(
+    range(out), to_string_view(format_str), args, internal::locale_ref(loc));
+}
+
+template <typename OutputIt, typename S, typename... Args>
+inline typename std::enable_if<
+    internal::is_string<S>::value &&
+    internal::is_output_iterator<OutputIt>::value, OutputIt>::type
+    format_to(OutputIt out, const std::locale &loc, const S &format_str,
+              const Args &... args) {
+  internal::check_format_string<Args...>(format_str);
+  typedef typename format_context_t<OutputIt, FMT_CHAR(S)>::type context;
+  format_arg_store<context, Args...> as{args...};
+  return vformat_to(out, loc, to_string_view(format_str),
+                    basic_format_args<context>(as));
+}
+
 FMT_END_NAMESPACE
 
 #endif  // FMT_LOCALE_H_

test/locale-test.cc

@@ -8,14 +8,27 @@
 #include "fmt/locale.h"
 #include "gmock.h"
 
-struct numpunct : std::numpunct<char> {
+template <typename Char>
+struct numpunct : std::numpunct<Char> {
  protected:
-  char do_thousands_sep() const FMT_OVERRIDE { return '~'; }
+  Char do_thousands_sep() const FMT_OVERRIDE { return '~'; }
 };
 
 TEST(LocaleTest, Format) {
-  std::locale loc;
-  EXPECT_EQ("1~234~567",
-            fmt::format(std::locale(loc, new numpunct()), "{:n}", 1234567));
-  EXPECT_EQ("1,234,567", fmt::format(loc, "{:n}", 1234567));
+  std::locale loc(std::locale(), new numpunct<char>());
+  EXPECT_EQ("1,234,567", fmt::format(std::locale(), "{:n}", 1234567));
+  EXPECT_EQ("1~234~567", fmt::format(loc, "{:n}", 1234567));
+  fmt::format_arg_store<fmt::format_context, int> as{1234567};
+  EXPECT_EQ("1~234~567", fmt::vformat(loc, "{:n}", fmt::format_args(as)));
+  std::string s;
+  fmt::format_to(std::back_inserter(s), loc, "{:n}", 1234567);
+  EXPECT_EQ("1~234~567", s);
+}
+
+TEST(LocaleTest, WFormat) {
+  std::locale loc(std::locale(), new numpunct<wchar_t>());
+  EXPECT_EQ(L"1,234,567", fmt::format(std::locale(), L"{:n}", 1234567));
+  EXPECT_EQ(L"1~234~567", fmt::format(loc, L"{:n}", 1234567));
+  fmt::format_arg_store<fmt::wformat_context, int> as{1234567};
+  EXPECT_EQ(L"1~234~567", fmt::vformat(loc, L"{:n}", fmt::wformat_args(as)));
 }