From c16217bf9b4fa78df058e698611cfcf9e1f19fe9 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <victor.zverovich@gmail.com>
Date: Wed, 30 Apr 2014 07:38:43 -0700
Subject: [PATCH] Test UTF8ToUTF16 and UTF16ToUTF8.

---
 format-test.cc | 18 ++++++++++++++++++
 format.cc      |  2 +-
 format.h       |  4 ++--
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/format-test.cc b/format-test.cc
index 7c62ddbb..ecc2ff4f 100644
--- a/format-test.cc
+++ b/format-test.cc
@@ -230,6 +230,24 @@ TEST(UtilTest, CountDigits) {
   TestCountDigits(uint64_t());
 }
 
+#ifdef _WIN32
+TEST(UtilTest, UTF16ToUTF8) {
+  std::string s = "ёжик";
+  UTF16ToUTF8 u(L"\x0451\x0436\x0438\x043A");
+  EXPECT_EQ(s, str(u));
+  EXPECT_EQ(s.size(), u.size());
+}
+
+TEST(UtilTest, UTF8ToUTF16) {
+  std::string s = "лошадка";
+  UTF8ToUTF16 u(s.c_str());
+  EXPECT_EQ(L"\x043B\x043E\x0448\x0430\x0434\x043A\x0430", str(u));
+  EXPECT_EQ(7, u.size());
+}
+
+// TODO: test UTF16ToUTF8::Convert
+#endif  // _WIN32
+
 class TestString {
  private:
   std::string value_;
diff --git a/format.cc b/format.cc
index 3daa1674..007f235c 100644
--- a/format.cc
+++ b/format.cc
@@ -244,7 +244,7 @@ void fmt::internal::FormatSystemErrorMessage(
       reinterpret_cast<LPWSTR>(system_message.ptr()), 0, 0)) {
     UTF16ToUTF8 utf8_message;
     if (!utf8_message.Convert(system_message.c_str())) {
-      out << message << ": " << utf8_message;
+      out << message << ": " << c_str(utf8_message);
       return;
     }
   }
diff --git a/format.h b/format.h
index b269824f..82130656 100644
--- a/format.h
+++ b/format.h
@@ -467,7 +467,7 @@ class UTF8ToUTF16 {
 
  public:
   explicit UTF8ToUTF16(StringRef s);
-  operator const wchar_t*() const { return &buffer_[0]; }
+  operator WStringRef() const { return WStringRef(&buffer_[0], size()); }
   size_t size() const { return buffer_.size() - 1; }
 };
 
@@ -480,7 +480,7 @@ class UTF16ToUTF8 {
  public:
   UTF16ToUTF8() {}
   explicit UTF16ToUTF8(WStringRef s);
-  operator const char*() const { return &buffer_[0]; }
+  operator StringRef() const { return StringRef(&buffer_[0], size()); }
   size_t size() const { return buffer_.size() - 1; }
 
   // Performs conversion returning a system error code instead of