From 21f209898954d32fc63d52143bd9481a6d64c274 Mon Sep 17 00:00:00 2001
From: Soren Lassen <soren@fb.com>
Date: Sat, 28 Sep 2013 17:53:52 -0700
Subject: [PATCH] Support constexpr StringPiece.

Test Plan: fbconfig folly/test --platform=gcc-4.8.1-glibc-2.17 && fbmake dbg _bin/folly/test/range_test && _bin/folly/test/range_test

Reviewed By: tudorb@fb.com

FB internal diff: D989142
---
 folly/Range.h            |  4 ++--
 folly/test/RangeTest.cpp | 10 ++++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/folly/Range.h b/folly/Range.h
index 107bdb00..cabd9078 100644
--- a/folly/Range.h
+++ b/folly/Range.h
@@ -152,8 +152,8 @@ public:
       : b_(start), e_(start + size) { }
 
   // Works only for Range<const char*>
-  /* implicit */ Range(Iter str)
-      : b_(str), e_(b_ + strlen(str)) {}
+  /* implicit */ constexpr Range(Iter str)
+      : b_(str), e_(str + strlen(str)) {}
   // Works only for Range<const char*>
   /* implicit */ Range(const std::string& str)
       : b_(str.data()), e_(b_ + str.size()) {}
diff --git a/folly/test/RangeTest.cpp b/folly/test/RangeTest.cpp
index 1ed678c8..445df424 100644
--- a/folly/test/RangeTest.cpp
+++ b/folly/test/RangeTest.cpp
@@ -290,6 +290,16 @@ TEST(StringPiece, InvalidRange) {
   EXPECT_THROW(a.subpiece(6), std::out_of_range);
 }
 
+constexpr char helloArray[] = "hello";
+
+TEST(StringPiece, Constexpr) {
+  constexpr StringPiece hello1("hello");
+  EXPECT_EQ("hello", hello1);
+
+  constexpr StringPiece hello2(helloArray);
+  EXPECT_EQ("hello", hello2);
+}
+
 TEST(qfind, UInt32_Ranges) {
   vector<uint32_t> a({1, 2, 3, 260, 5});
   vector<uint32_t> b({2, 3, 4});
-- 
2.34.1