From 78890b3f9ceac28d74c3382767f9c7bdf16b4542 Mon Sep 17 00:00:00 2001
From: Tavian Barnes <tavianator@tavianator.com>
Date: Thu, 14 Jul 2016 11:11:22 -0700
Subject: [PATCH] fbstring: Fix std::hash specializations for non-char types

Summary: Closes https://github.com/facebook/folly/pull/407

Reviewed By: ot

Differential Revision: D3428571

Pulled By: Orvid

fbshipit-source-id: 0b82afae2df24803250e8d6005e2e59bbc8348c9
---
 folly/FBString.h            |  2 +-
 folly/test/FBStringTest.cpp | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/folly/FBString.h b/folly/FBString.h
index 0c8273e5..9a50e299 100644
--- a/folly/FBString.h
+++ b/folly/FBString.h
@@ -2441,7 +2441,7 @@ _GLIBCXX_END_NAMESPACE_VERSION
 #define FOLLY_FBSTRING_HASH1(T) \
   template <> \
   struct hash< ::folly::basic_fbstring<T> > { \
-    size_t operator()(const ::folly::fbstring& s) const { \
+    size_t operator()(const ::folly::basic_fbstring<T>& s) const { \
       return ::folly::hash::fnv32_buf(s.data(), s.size()); \
     } \
   };
diff --git a/folly/test/FBStringTest.cpp b/folly/test/FBStringTest.cpp
index e8644482..1bc36391 100644
--- a/folly/test/FBStringTest.cpp
+++ b/folly/test/FBStringTest.cpp
@@ -1287,6 +1287,18 @@ TEST(FBString, testHash) {
   EXPECT_NE(hashfunc(a), hashfunc(b));
 }
 
+TEST(FBString, testHashChar16) {
+  using u16fbstring = basic_fbstring<char16_t>;
+  u16fbstring a;
+  u16fbstring b;
+  a.push_back(0);
+  a.push_back(1);
+  b.push_back(0);
+  b.push_back(2);
+  std::hash<u16fbstring> hashfunc;
+  EXPECT_NE(hashfunc(a), hashfunc(b));
+}
+
 TEST(FBString, testFrontBack) {
   fbstring str("hello");
   EXPECT_EQ(str.front(), 'h');
-- 
2.34.1