From 32ec13f1490f14876d52e72b5047eaac2e335008 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <victor.zverovich@gmail.com>
Date: Sat, 25 Mar 2017 08:20:06 -0700
Subject: [PATCH] Switch to C++ locale

---
 fmt/format.h        | 36 ++++++++++++++----------------------
 test/format-test.cc | 25 ++-----------------------
 test/util-test.cc   | 14 --------------
 3 files changed, 16 insertions(+), 59 deletions(-)

diff --git a/fmt/format.h b/fmt/format.h
index 502a6ab8..1e96513b 100644
--- a/fmt/format.h
+++ b/fmt/format.h
@@ -30,11 +30,11 @@
 
 #include <array>
 #include <cassert>
-#include <clocale>
 #include <cmath>
 #include <cstdio>
 #include <cstring>
 #include <limits>
+#include <locale>
 #include <memory>
 #include <stdexcept>
 #include <string>
@@ -645,6 +645,8 @@ class basic_buffer {
 
   T &operator[](std::size_t index) { return ptr_[index]; }
   const T &operator[](std::size_t index) const { return ptr_[index]; }
+
+  virtual const std::locale* locale() const { return 0; }
 };
 
 template <typename T>
@@ -962,18 +964,18 @@ struct no_thousands_sep {
 };
 
 // A functor that adds a thousands separator.
+template <typename Char>
 class add_thousands_sep {
  private:
-  fmt::string_view sep_;
+  fmt::basic_string_view<Char> sep_;
 
   // Index of a decimal digit with the least significant digit having index 0.
   unsigned digit_index_;
 
  public:
-  explicit add_thousands_sep(fmt::string_view sep)
+  explicit add_thousands_sep(fmt::basic_string_view<Char> sep)
     : sep_(sep), digit_index_(0) {}
 
-  template <typename Char>
   void operator()(Char *&buffer) {
     if (++digit_index_ % 3 != 0)
       return;
@@ -1483,21 +1485,6 @@ basic_arg<Context> make_arg(const T &value) {
   return arg;
 }
 
-template <typename T, T> struct lconv_check {
-  lconv_check(int) {}
-};
-
-// Returns the thousands separator for the current locale.
-// We check if ``lconv`` contains ``thousands_sep`` because on Android
-// ``lconv`` is stubbed as an empty struct.
-template <typename LConv>
-inline string_view thousands_sep(
-    LConv *lc, lconv_check<char *LConv::*, &LConv::thousands_sep> = 0) {
-  return lc->thousands_sep;
-}
-
-inline fmt::string_view thousands_sep(...) { return ""; }
-
 #define FMT_CONCAT(a, b) a##b
 
 #if FMT_GCC_VERSION >= 407
@@ -2323,7 +2310,7 @@ class basic_writer {
 
   /**
     \rst
-    Destroys a ``basic_writer`` object.
+    Destroys the ``basic_writer`` object.
     \endrst
    */
   virtual ~basic_writer() {}
@@ -2629,12 +2616,17 @@ void basic_writer<Char>::write_int(T value, Spec spec) {
   }
   case 'n': {
     unsigned num_digits = internal::count_digits(abs_value);
-    fmt::string_view sep = internal::thousands_sep(std::localeconv());
+    const std::locale *loc = buffer_.locale();
+    if (!loc)
+      loc = &std::locale::classic();
+    Char thousands_sep =
+        std::use_facet<std::numpunct<Char>>(*loc).thousands_sep();
+    fmt::basic_string_view<Char> sep(&thousands_sep, 1);
     unsigned size = static_cast<unsigned>(
           num_digits + sep.size() * ((num_digits - 1) / 3));
     CharPtr p = prepare_int_buffer(size, spec, prefix, prefix_size) + 1;
     internal::format_decimal(get(p), abs_value, 0,
-                             internal::add_thousands_sep(sep));
+                             internal::add_thousands_sep<Char>(sep));
     break;
   }
   default:
diff --git a/test/format-test.cc b/test/format-test.cc
index 66397856..b5414d81 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -43,22 +43,6 @@
 // Test that the library compiles if None is defined to 0 as done by xlib.h.
 #define None 0
 
-struct LocaleMock {
-  static LocaleMock *instance;
-
-  MOCK_METHOD0(localeconv, lconv *());
-} *LocaleMock::instance;
-
-namespace fmt {
-namespace std {
-using namespace ::std;
-lconv *localeconv() {
-  return LocaleMock::instance ?
-        LocaleMock::instance->localeconv() : ::std::localeconv();
-}
-}
-}
-
 #include "fmt/format.h"
 
 #include "util.h"
@@ -1115,14 +1099,9 @@ TEST(FormatterTest, FormatOct) {
 }
 
 TEST(FormatterTest, FormatIntLocale) {
-  ScopedMock<LocaleMock> mock;
-  lconv lc = {};
-  char sep[] = "--";
-  lc.thousands_sep = sep;
-  EXPECT_CALL(mock, localeconv()).Times(3).WillRepeatedly(testing::Return(&lc));
   EXPECT_EQ("123", format("{:n}", 123));
-  EXPECT_EQ("1--234", format("{:n}", 1234));
-  EXPECT_EQ("1--234--567", format("{:n}", 1234567));
+  EXPECT_EQ("1,234", format("{:n}", 1234));
+  EXPECT_EQ("1,234,567", format("{:n}", 1234567));
 }
 
 TEST(FormatterTest, FormatFloat) {
diff --git a/test/util-test.cc b/test/util-test.cc
index fc805b8f..1ca29817 100644
--- a/test/util-test.cc
+++ b/test/util-test.cc
@@ -845,17 +845,3 @@ TEST(UtilTest, Conditional) {
   fmt::internal::conditional<false, int, char>::type *pc = &c;
   (void)pc;
 }
-
-struct TestLConv {
-  char *thousands_sep;
-};
-
-struct EmptyLConv {};
-
-TEST(UtilTest, ThousandsSep) {
-  char foo[] = "foo";
-  TestLConv lc = {foo};
-  EXPECT_EQ("foo", fmt::internal::thousands_sep(&lc).to_string());
-  EmptyLConv empty_lc;
-  EXPECT_EQ("", fmt::internal::thousands_sep(&empty_lc));
-}