base/template_util_unittest.cc

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/template_util.h"
   6 #include "testing/gtest/include/gtest/gtest.h"
   7
   8 namespace base {
   9 namespace {
  10
  11 struct AStruct {};
  12 class AClass {};
  13 enum AnEnum {};
  14
  15 class Parent {};
  16 class Child : public Parent {};
  17
  18 TEST(TemplateUtilTest, IsPointer) {
  19   EXPECT_FALSE(is_pointer<int>::value);
  20   EXPECT_FALSE(is_pointer<int&>::value);
  21   EXPECT_TRUE(is_pointer<int*>::value);
  22   EXPECT_TRUE(is_pointer<const int*>::value);
  23 }
  24
  25 TEST(TemplateUtilTest, IsArray) {
  26   EXPECT_FALSE(is_array<int>::value);
  27   EXPECT_FALSE(is_array<int*>::value);
  28   EXPECT_FALSE(is_array<int(*)[3]>::value);
  29   EXPECT_TRUE(is_array<int[]>::value);
  30   EXPECT_TRUE(is_array<const int[]>::value);
  31   EXPECT_TRUE(is_array<int[3]>::value);
  32 }
  33
  34 TEST(TemplateUtilTest, IsNonConstReference) {
  35   EXPECT_FALSE(is_non_const_reference<int>::value);
  36   EXPECT_FALSE(is_non_const_reference<const int&>::value);
  37   EXPECT_TRUE(is_non_const_reference<int&>::value);
  38 }
  39
  40 TEST(TemplateUtilTest, IsConvertible) {
  41   // Extra parens needed to make EXPECT_*'s parsing happy. Otherwise,
  42   // it sees the equivalent of
  43   //
  44   //  EXPECT_TRUE( (is_convertible < Child), (Parent > ::value));
  45   //
  46   // Silly C++.
  47   EXPECT_TRUE( (is_convertible<Child, Parent>::value) );
  48   EXPECT_FALSE( (is_convertible<Parent, Child>::value) );
  49   EXPECT_FALSE( (is_convertible<Parent, AStruct>::value) );
  50
  51   EXPECT_TRUE( (is_convertible<int, double>::value) );
  52   EXPECT_TRUE( (is_convertible<int*, void*>::value) );
  53   EXPECT_FALSE( (is_convertible<void*, int*>::value) );
  54
  55   // Array types are an easy corner case.  Make sure to test that
  56   // it does indeed compile.
  57   EXPECT_FALSE( (is_convertible<int[10], double>::value) );
  58   EXPECT_FALSE( (is_convertible<double, int[10]>::value) );
  59   EXPECT_TRUE( (is_convertible<int[10], int*>::value) );
  60 }
  61
  62 TEST(TemplateUtilTest, IsSame) {
  63   EXPECT_FALSE( (is_same<Child, Parent>::value) );
  64   EXPECT_FALSE( (is_same<Parent, Child>::value) );
  65   EXPECT_TRUE( (is_same<Parent, Parent>::value) );
  66
  67   EXPECT_TRUE( (is_same<int*, int*>::value) );
  68   EXPECT_TRUE( (is_same<int, int>::value) );
  69   EXPECT_TRUE( (is_same<void, void>::value) );
  70   EXPECT_FALSE( (is_same<int, double>::value) );
  71 }
  72
  73 TEST(TemplateUtilTest, IsClass) {
  74   EXPECT_TRUE(is_class<AStruct>::value);
  75   EXPECT_TRUE(is_class<AClass>::value);
  76
  77   EXPECT_FALSE(is_class<AnEnum>::value);
  78   EXPECT_FALSE(is_class<int>::value);
  79   EXPECT_FALSE(is_class<char*>::value);
  80   EXPECT_FALSE(is_class<int&>::value);
  81   EXPECT_FALSE(is_class<char[3]>::value);
  82 }
  83
  84 }  // namespace
  85 }  // namespace base