mfbt/tests/TestFunctionTypeTraits.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/FunctionTypeTraits.h"
   8
   9 #include <functional>
  10
  11 using mozilla::FunctionTypeTraits;
  12
  13 void f0() {}
  14
  15 int f1(char) { return 0; }
  16
  17 #ifdef NS_HAVE_STDCALL
  18 void NS_STDCALL f0s() {}
  19
  20 int NS_STDCALL f1s(char) { return 0; }
  21 #endif  // NS_HAVE_STDCALL
  22
  23 struct S {
  24   void f0() {}
  25   void f0c() const {}
  26   int f1(char) { return 0; }
  27   int f1c(char) const { return 0; }
  28 #ifdef NS_HAVE_STDCALL
  29   void NS_STDCALL f0s() {}
  30   void NS_STDCALL f0cs() const {}
  31   int NS_STDCALL f1s(char) { return 0; }
  32   int NS_STDCALL f1cs(char) const { return 0; }
  33 #endif  // NS_HAVE_STDCALL
  34 };
  35
  36 static_assert(
  37     std::is_same<typename FunctionTypeTraits<decltype(f0)>::ReturnType,
  38                  void>::value,
  39     "f0 returns void");
  40 static_assert(FunctionTypeTraits<decltype(f0)>::arity == 0,
  41               "f0 takes no parameters");
  42 static_assert(
  43     std::is_same<
  44         typename FunctionTypeTraits<decltype(f0)>::template ParameterType<0>,
  45         void>::value,
  46     "f0 has no first parameter");
  47
  48 static_assert(
  49     std::is_same<typename FunctionTypeTraits<decltype(&S::f0)>::ReturnType,
  50                  void>::value,
  51     "S::f0 returns void");
  52 static_assert(FunctionTypeTraits<decltype(&S::f0)>::arity == 0,
  53               "S::f0 takes no parameters");
  54 static_assert(std::is_same<typename FunctionTypeTraits<
  55                                decltype(&S::f0)>::template ParameterType<0>,
  56                            void>::value,
  57               "S::f0 has no first parameter");
  58
  59 static_assert(
  60     std::is_same<typename FunctionTypeTraits<decltype(&S::f0c)>::ReturnType,
  61                  void>::value,
  62     "S::f0c returns void");
  63 static_assert(FunctionTypeTraits<decltype(&S::f0c)>::arity == 0,
  64               "S::f0c takes no parameters");
  65 static_assert(std::is_same<typename FunctionTypeTraits<
  66                                decltype(&S::f0c)>::template ParameterType<0>,
  67                            void>::value,
  68               "S::f0c has no first parameter");
  69
  70 static_assert(
  71     std::is_same<typename FunctionTypeTraits<decltype(f1)>::ReturnType,
  72                  int>::value,
  73     "f1 returns int");
  74 static_assert(FunctionTypeTraits<decltype(f1)>::arity == 1,
  75               "f1 takes one parameter");
  76 static_assert(
  77     std::is_same<
  78         typename FunctionTypeTraits<decltype(f1)>::template ParameterType<0>,
  79         char>::value,
  80     "f1 takes a char");
  81
  82 static_assert(
  83     std::is_same<typename FunctionTypeTraits<decltype(&S::f1)>::ReturnType,
  84                  int>::value,
  85     "S::f1 returns int");
  86 static_assert(FunctionTypeTraits<decltype(&S::f1)>::arity == 1,
  87               "S::f1 takes one parameter");
  88 static_assert(std::is_same<typename FunctionTypeTraits<
  89                                decltype(&S::f1)>::template ParameterType<0>,
  90                            char>::value,
  91               "S::f1 takes a char");
  92
  93 static_assert(
  94     std::is_same<typename FunctionTypeTraits<decltype(&S::f1c)>::ReturnType,
  95                  int>::value,
  96     "S::f1c returns int");
  97 static_assert(FunctionTypeTraits<decltype(&S::f1c)>::arity == 1,
  98               "S::f1c takes one parameter");
  99 static_assert(std::is_same<typename FunctionTypeTraits<
 100                                decltype(&S::f1c)>::template ParameterType<0>,
 101                            char>::value,
 102               "S::f1c takes a char");
 103
 104 #ifdef NS_HAVE_STDCALL
 105 static_assert(
 106     std::is_same<typename FunctionTypeTraits<decltype(f0s)>::ReturnType,
 107                  void>::value,
 108     "f0s returns void");
 109 static_assert(FunctionTypeTraits<decltype(f0s)>::arity == 0,
 110               "f0s takes no parameters");
 111 static_assert(
 112     std::is_same<
 113         typename FunctionTypeTraits<decltype(f0s)>::template ParameterType<0>,
 114         void>::value,
 115     "f0s has no first parameter");
 116
 117 static_assert(
 118     std::is_same<typename FunctionTypeTraits<decltype(&S::f0s)>::ReturnType,
 119                  void>::value,
 120     "S::f0s returns void");
 121 static_assert(FunctionTypeTraits<decltype(&S::f0s)>::arity == 0,
 122               "S::f0s takes no parameters");
 123 static_assert(std::is_same<typename FunctionTypeTraits<
 124                                decltype(&S::f0s)>::template ParameterType<0>,
 125                            void>::value,
 126               "S::f0s has no first parameter");
 127
 128 static_assert(
 129     std::is_same<typename FunctionTypeTraits<decltype(&S::f0cs)>::ReturnType,
 130                  void>::value,
 131     "S::f0cs returns void");
 132 static_assert(FunctionTypeTraits<decltype(&S::f0cs)>::arity == 0,
 133               "S::f0cs takes no parameters");
 134 static_assert(std::is_same<typename FunctionTypeTraits<
 135                                decltype(&S::f0cs)>::template ParameterType<0>,
 136                            void>::value,
 137               "S::f0cs has no first parameter");
 138
 139 static_assert(
 140     std::is_same<typename FunctionTypeTraits<decltype(f1s)>::ReturnType,
 141                  int>::value,
 142     "f1s returns int");
 143 static_assert(FunctionTypeTraits<decltype(f1s)>::arity == 1,
 144               "f1s takes one parameter");
 145 static_assert(
 146     std::is_same<
 147         typename FunctionTypeTraits<decltype(f1s)>::template ParameterType<0>,
 148         char>::value,
 149     "f1s takes a char");
 150
 151 static_assert(
 152     std::is_same<typename FunctionTypeTraits<decltype(&S::f1s)>::ReturnType,
 153                  int>::value,
 154     "S::f1s returns int");
 155 static_assert(FunctionTypeTraits<decltype(&S::f1s)>::arity == 1,
 156               "S::f1s takes one parameter");
 157 static_assert(std::is_same<typename FunctionTypeTraits<
 158                                decltype(&S::f1s)>::template ParameterType<0>,
 159                            char>::value,
 160               "S::f1s takes a char");
 161
 162 static_assert(
 163     std::is_same<typename FunctionTypeTraits<decltype(&S::f1cs)>::ReturnType,
 164                  int>::value,
 165     "S::f1cs returns int");
 166 static_assert(FunctionTypeTraits<decltype(&S::f1cs)>::arity == 1,
 167               "S::f1cs takes one parameter");
 168 static_assert(std::is_same<typename FunctionTypeTraits<
 169                                decltype(&S::f1cs)>::template ParameterType<0>,
 170                            char>::value,
 171               "S::f1cs takes a char");
 172 #endif  // NS_HAVE_STDCALL
 173
 174 template <typename F>
 175 void TestVoidVoid(F&&) {
 176   static_assert(
 177       std::is_same<typename FunctionTypeTraits<F>::ReturnType, void>::value,
 178       "Should return void");
 179   static_assert(FunctionTypeTraits<F>::arity == 0, "Should take no parameters");
 180   static_assert(
 181       std::is_same<typename FunctionTypeTraits<F>::template ParameterType<0>,
 182                    void>::value,
 183       "Should have no first parameter");
 184 }
 185
 186 template <typename F>
 187 void TestIntChar(F&&) {
 188   static_assert(
 189       std::is_same<typename FunctionTypeTraits<F>::ReturnType, int>::value,
 190       "Should return int");
 191   static_assert(FunctionTypeTraits<F>::arity == 1, "Should take one parameter");
 192   static_assert(
 193       std::is_same<typename FunctionTypeTraits<F>::template ParameterType<0>,
 194                    char>::value,
 195       "Should take a char");
 196 }
 197
 198 int main() {
 199   TestVoidVoid(f0);
 200   TestVoidVoid(&f0);
 201   TestVoidVoid(&S::f0);
 202   TestVoidVoid(&S::f0c);
 203   TestVoidVoid([]() {});
 204   std::function<void()> ff0 = f0;
 205   TestVoidVoid(ff0);
 206
 207   TestIntChar(f1);
 208   TestIntChar(&f1);
 209   TestIntChar(&S::f1);
 210   TestIntChar(&S::f1c);
 211   TestIntChar([](char) { return 0; });
 212   std::function<int(char)> ff1 = f1;
 213   TestIntChar(ff1);
 214
 215 #ifdef NS_HAVE_STDCALL
 216   TestVoidVoid(f0s);
 217   TestVoidVoid(&f0s);
 218   TestVoidVoid(&S::f0s);
 219   TestVoidVoid(&S::f0cs);
 220   std::function<void()> ff0s = f0s;
 221   TestVoidVoid(ff0s);
 222
 223   TestIntChar(f1s);
 224   TestIntChar(&f1s);
 225   TestIntChar(&S::f1s);
 226   TestIntChar(&S::f1cs);
 227   std::function<int(char)> ff1s = f1s;
 228   TestIntChar(ff1s);
 229 #endif  // NS_HAVE_STDCALL
 230
 231   return 0;
 232 }