diff --git a/llvm/unittests/ADT/SmallStringTest.cpp b/llvm/unittests/ADT/SmallStringTest.cpp
index 9398e99..ff04f5b 100644
--- a/llvm/unittests/ADT/SmallStringTest.cpp
+++ b/llvm/unittests/ADT/SmallStringTest.cpp
@@ -50,13 +50,6 @@
   EXPECT_STREQ("aaa", theString.c_str());
 }
 
-TEST_F(SmallStringTest, AssignIterPair) {
-  StringRef abc = "abc";
-  theString.assign(abc.begin(), abc.end());
-  EXPECT_EQ(3u, theString.size());
-  EXPECT_STREQ("abc", theString.c_str());
-}
-
 TEST_F(SmallStringTest, AssignStringRef) {
   StringRef abc = "abc";
   theString.assign(abc);
@@ -88,6 +81,23 @@
   EXPECT_STREQ("abcabc", theString.c_str());
 }
 
+TEST_F(SmallStringTest, PlusEqualsStringRef) {
+  StringRef abc = "abc";
+  theString += abc;
+  theString += abc;
+  EXPECT_EQ(6u, theString.size());
+  EXPECT_STREQ("abcabc", theString.c_str());
+}
+
+TEST_F(SmallStringTest, PlusEqualsSmallVector) {
+  StringRef abc = "abc";
+  SmallVector<char, 10> abcVec(abc.begin(), abc.end());
+  theString += abcVec;
+  theString += abcVec;
+  EXPECT_EQ(6u, theString.size());
+  EXPECT_STREQ("abcabc", theString.c_str());
+}
+
 TEST_F(SmallStringTest, AppendSmallVector) {
   StringRef abc = "abc";
   SmallVector<char, 10> abcVec(abc.begin(), abc.end());