mfbt/tests/TestMacroForEach.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
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/Assertions.h"
   8 #include "mozilla/MacroForEach.h"
   9
  10 #define HELPER_IDENTITY(x) x
  11 #define HELPER_IDENTITY_PLUS(x) x +
  12 static_assert(MOZ_FOR_EACH(HELPER_IDENTITY_PLUS, (), (10)) 0 == 10, "");
  13 static_assert(MOZ_FOR_EACH(HELPER_IDENTITY_PLUS, (), (1, 1, 1)) 0 == 3, "");
  14 static_assert(MOZ_FOR_EACH_SEPARATED(HELPER_IDENTITY, (+), (), (10)) == 10, "");
  15 static_assert(MOZ_FOR_EACH_SEPARATED(HELPER_IDENTITY, (+), (), (1, 1, 1)) == 3,
  16               "");
  17
  18 #define HELPER_ONE_PLUS(x) HELPER_IDENTITY_PLUS(1)
  19 static_assert(MOZ_FOR_EACH(HELPER_ONE_PLUS, (), ()) 0 == 0, "");
  20
  21 #define HELPER_DEFINE_VAR(x) const int test1_##x = x;
  22 MOZ_FOR_EACH(HELPER_DEFINE_VAR, (), (10, 20))
  23 static_assert(test1_10 == 10 && test1_20 == 20, "");
  24
  25 #define HELPER_DEFINE_VAR2(k, x) const int test2_##x = k + x;
  26 MOZ_FOR_EACH(HELPER_DEFINE_VAR2, (5, ), (10, 20))
  27 static_assert(test2_10 == 15 && test2_20 == 25, "");
  28
  29 #define HELPER_DEFINE_PARAM(t, n) t n
  30 constexpr int test(MOZ_FOR_EACH_SEPARATED(HELPER_DEFINE_PARAM, (, ), (int, ),
  31                                           (a, b, c))) {
  32   return a + b + c;
  33 }
  34 static_assert(test(1, 2, 3) == 6, "");
  35
  36 int main() {
  37 #define HELPER_IDENTITY_COMMA(k1, k2, x) k1, k2, x,
  38   const int a[] = {MOZ_FOR_EACH(HELPER_IDENTITY_COMMA, (1, 2, ), (10, 20, 30))};
  39   MOZ_RELEASE_ASSERT(a[0] == 1 && a[1] == 2 && a[2] == 10 && a[3] == 1 &&
  40                          a[4] == 2 && a[5] == 20 && a[6] == 1 && a[7] == 2 &&
  41                          a[8] == 30,
  42                      "MOZ_FOR_EACH args enumerated in incorrect order");
  43   return 0;
  44 }