unittests/ADT/FunctionRefTest.cpp

   1 //===- llvm/unittest/ADT/MakeUniqueTest.cpp - make_unique unit tests ------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "llvm/ADT/STLExtras.h"
  11 #include "gtest/gtest.h"
  12
  13 using namespace llvm;
  14
  15 namespace {
  16
  17 // Ensure that there is a default constructor and we can test for a null
  18 // function_ref.
  19 TEST(FunctionRefTest, Null) {
  20   function_ref<int()> F;
  21   EXPECT_FALSE(F);
  22
  23   auto L = [] { return 1; };
  24   F = L;
  25   EXPECT_TRUE(F);
  26
  27   F = {};
  28   EXPECT_FALSE(F);
  29 }
  30
  31 // Ensure that copies of a function_ref copy the underlying state rather than
  32 // causing one function_ref to chain to the next.
  33 TEST(FunctionRefTest, Copy) {
  34   auto A = [] { return 1; };
  35   auto B = [] { return 2; };
  36   function_ref<int()> X = A;
  37   function_ref<int()> Y = X;
  38   X = B;
  39   EXPECT_EQ(1, Y());
  40 }
  41
  42 }