From 683a74501ffb541ab8687eab6e1f03d94f542e3a Mon Sep 17 00:00:00 2001
From: Alexey Ochapov <alexez@alexez.com>
Date: Wed, 2 Dec 2020 18:14:57 +0300
Subject: [PATCH] fix formatting with empty compiled format string (#2042)

---
 include/fmt/compile.h | 2 +-
 test/compile-test.cc  | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/fmt/compile.h b/include/fmt/compile.h
index 0f7a9005..affd793e 100644
--- a/include/fmt/compile.h
+++ b/include/fmt/compile.h
@@ -643,7 +643,7 @@ FMT_INLINE std::basic_string<typename S::char_type> format(const S&,
 #ifdef __cpp_if_constexpr
   if constexpr (std::is_same<typename S::char_type, char>::value) {
     constexpr basic_string_view<typename S::char_type> str = S();
-    if (str.size() == 2 && str[0] == '{' && str[1] == '}')
+    if constexpr (str.size() == 2 && str[0] == '{' && str[1] == '}')
       return fmt::to_string(detail::first(args...));
   }
 #endif
diff --git a/test/compile-test.cc b/test/compile-test.cc
index 660f4fb1..7ae28772 100644
--- a/test/compile-test.cc
+++ b/test/compile-test.cc
@@ -173,6 +173,10 @@ TEST(CompileTest, TextAndArg) {
   EXPECT_EQ(">>>42<<<", fmt::format(FMT_COMPILE(">>>{}<<<"), 42));
   EXPECT_EQ("42!", fmt::format(FMT_COMPILE("{}!"), 42));
 }
+
+TEST(CompileTest, Empty) {
+  EXPECT_EQ("", fmt::format(FMT_COMPILE("")));
+}
 #endif
 
 #if __cplusplus >= 202002L