--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/unittests/ADT/VariadicFunctionTest.cpp	Thu Dec 12 13:56:28 2013 +0900
@@ -0,0 +1,110 @@
+//===----------- VariadicFunctionTest.cpp - VariadicFunction unit tests ---===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "gtest/gtest.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/VariadicFunction.h"
+
+using namespace llvm;
+namespace {
+
+// Defines a variadic function StringCat() to join strings.
+// StringCat()'s arguments and return value have class types.
+std::string StringCatImpl(ArrayRef<const std::string *> Args) {
+  std::string S;
+  for (unsigned i = 0, e = Args.size(); i < e; ++i)
+    S += *Args[i];
+  return S;
+}
+const VariadicFunction<std::string, std::string, StringCatImpl> StringCat = {};
+
+TEST(VariadicFunctionTest, WorksForClassTypes) {
+  EXPECT_EQ("", StringCat());
+  EXPECT_EQ("a", StringCat("a"));
+  EXPECT_EQ("abc", StringCat("a", "bc"));
+  EXPECT_EQ("0123456789abcdefghijklmnopqrstuv",
+            StringCat("0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
+                      "a", "b", "c", "d", "e", "f", "g", "h", "i", "j",
+                      "k", "l", "m", "n", "o", "p", "q", "r", "s", "t",
+                      "u", "v"));
+}
+
+// Defines a variadic function Sum(), whose arguments and return value
+// have primitive types.
+// The return type of SumImp() is deliberately different from its
+// argument type, as we want to test that this works.
+long SumImpl(ArrayRef<const int *> Args) {
+  long Result = 0;
+  for (unsigned i = 0, e = Args.size(); i < e; ++i)
+    Result += *Args[i];
+  return Result;
+}
+const VariadicFunction<long, int, SumImpl> Sum = {};
+
+TEST(VariadicFunctionTest, WorksForPrimitiveTypes) {
+  EXPECT_EQ(0, Sum());
+  EXPECT_EQ(1, Sum(1));
+  EXPECT_EQ(12, Sum(10, 2));
+  EXPECT_EQ(1234567, Sum(1000000, 200000, 30000, 4000, 500, 60, 7));
+}
+
+// Appends an array of strings to dest and returns the number of
+// characters appended.
+int StringAppendImpl(std::string *Dest, ArrayRef<const std::string *> Args) {
+  int Chars = 0;
+  for (unsigned i = 0, e = Args.size(); i < e; ++i) {
+    Chars += Args[i]->size();
+    *Dest += *Args[i];
+  }
+  return Chars;
+}
+const VariadicFunction1<int, std::string *, std::string,
+                        StringAppendImpl> StringAppend = {};
+
+TEST(VariadicFunction1Test, Works) {
+  std::string S0("hi");
+  EXPECT_EQ(0, StringAppend(&S0));
+  EXPECT_EQ("hi", S0);
+
+  std::string S1("bin");
+  EXPECT_EQ(2, StringAppend(&S1, "go"));
+  EXPECT_EQ("bingo", S1);
+
+  std::string S4("Fab4");
+  EXPECT_EQ(4 + 4 + 6 + 5,
+            StringAppend(&S4, "John", "Paul", "George", "Ringo"));
+  EXPECT_EQ("Fab4JohnPaulGeorgeRingo", S4);
+}
+
+// Counts how many optional arguments fall in the given range.
+// Returns the result in *num_in_range.  We make the return type void
+// as we want to test that VariadicFunction* can handle it.
+void CountInRangeImpl(int *NumInRange, int Low, int High,
+                      ArrayRef<const int *> Args) {
+  *NumInRange = 0;
+  for (unsigned i = 0, e = Args.size(); i < e; ++i)
+    if (Low <= *Args[i] && *Args[i] <= High)
+      ++(*NumInRange);
+}
+const VariadicFunction3<void, int *, int, int, int,
+                        CountInRangeImpl> CountInRange = {};
+
+TEST(VariadicFunction3Test, Works) {
+  int N = -1;
+  CountInRange(&N, -100, 100);
+  EXPECT_EQ(0, N);
+
+  CountInRange(&N, -100, 100, 42);
+  EXPECT_EQ(1, N);
+
+  CountInRange(&N, -100, 100, 1, 999, -200, 42);
+  EXPECT_EQ(2, N);
+}
+
+}  // namespace