From ed2dfe512422c7473759618228f71f67019475b5 Mon Sep 17 00:00:00 2001
From: vitaut <victor.zverovich@gmail.com>
Date: Tue, 9 Jun 2015 08:20:44 -0700
Subject: [PATCH] Implement writing narrow strings into a wide writer

---
 format.h            | 12 ++++++++++--
 test/format-test.cc |  1 +
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/format.h b/format.h
index 2e558edc..bee4cf78 100644
--- a/format.h
+++ b/format.h
@@ -368,14 +368,16 @@ class Buffer {
   }
 
   /** Appends data to the end of the buffer. */
-  void append(const T *begin, const T *end);
+  template <typename U>
+  void append(const U *begin, const U *end);
 
   T &operator[](std::size_t index) { return ptr_[index]; }
   const T &operator[](std::size_t index) const { return ptr_[index]; }
 };
 
 template <typename T>
-void Buffer<T>::append(const T *begin, const T *end) {
+template <typename U>
+void Buffer<T>::append(const U *begin, const U *end) {
   std::ptrdiff_t num_elements = end - begin;
   if (size_ + num_elements > capacity_)
     grow(size_ + num_elements);
@@ -1923,6 +1925,12 @@ class BasicWriter {
     return *this;
   }
 
+  BasicWriter &operator<<(typename internal::WCharHelper<StringRef, Char>::Supported value) {
+    const char *str = value.c_str();
+    buffer_.append(str, str + value.size());
+    return *this;
+  }
+
   template <typename T, typename Spec, typename FillChar>
   BasicWriter &operator<<(IntFormatSpec<T, Spec, FillChar> spec) {
     internal::CharTraits<Char>::convert(FillChar());
diff --git a/test/format-test.cc b/test/format-test.cc
index 8660b945..11d5425b 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -325,6 +325,7 @@ TEST(WriterTest, WriteWideChar) {
 
 TEST(WriterTest, WriteString) {
   CHECK_WRITE_CHAR("abc");
+  CHECK_WRITE_WCHAR("abc");
   // The following line shouldn't compile:
   //MemoryWriter() << L"abc";
 }