From 065889a5937e01157eb5278c5865340d55a0b6c6 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <viz@fb.com>
Date: Sat, 8 Aug 2020 07:01:21 -0700
Subject: [PATCH] Use correct capacity in iterator_buffer (#1807)

---
 include/fmt/core.h  | 2 +-
 test/format-test.cc | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/fmt/core.h b/include/fmt/core.h
index 359deb25..f8b2c709 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -771,7 +771,7 @@ class iterator_buffer : public Traits, public buffer<T> {
   void flush();
 
  public:
-  explicit iterator_buffer(OutputIt out, size_t n = 0)
+  explicit iterator_buffer(OutputIt out, size_t n = buffer_size)
       : Traits(n),
         buffer<T>(data_, 0, n < size_t(buffer_size) ? n : size_t(buffer_size)),
         out_(out) {}
diff --git a/test/format-test.cc b/test/format-test.cc
index b48fd6be..bd3dcfdb 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -1946,6 +1946,12 @@ TEST(FormatTest, FormattedSize) {
   EXPECT_EQ(2u, fmt::formatted_size("{}", 42));
 }
 
+TEST(FormatTest, FormatTo) {
+  std::vector<char> v;
+  fmt::format_to(std::back_inserter(v), "{}", "foo");
+  EXPECT_EQ(string_view(v.data(), v.size()), "foo");
+}
+
 TEST(FormatTest, FormatToN) {
   char buffer[4];
   buffer[3] = 'x';