libstdc++-v3/testsuite/23_containers/unordered_set/modifiers/swap-2.cc

   1 // { dg-do run { target c++11 } }
   2
   3 // Bug 117921 - containers do not use ADL swap for Compare, Pred or Hash types
   4
   5 #include <unordered_set>
   6 #include <testsuite_hooks.h>
   7
   8 namespace adl
   9 {
  10   struct Hash : std::hash<int>
  11   {
  12     static bool swapped;
  13     friend void swap(Hash&, Hash&) { swapped = true; }
  14   };
  15   bool Hash::swapped = false;
  16
  17   struct Eq : std::equal_to<int>
  18   {
  19     static bool swapped;
  20     friend void swap(Eq&, Eq&) { swapped = true; }
  21   };
  22   bool Eq::swapped = false;
  23
  24   struct Allocator_base
  25   {
  26     static bool swapped;
  27   };
  28   bool Allocator_base::swapped = false;
  29
  30   using std::size_t;
  31
  32   template<typename T>
  33     struct Allocator : Allocator_base
  34     {
  35       using value_type = T;
  36
  37       Allocator() { }
  38       template<typename U> Allocator(const Allocator<U>&) { }
  39
  40       T* allocate(size_t n) { return std::allocator<T>().allocate(n); }
  41       void deallocate(T* p, size_t n) { std::allocator<T>().deallocate(p, n); }
  42
  43       using propagate_on_container_swap = std::true_type;
  44
  45       friend void swap(Allocator&, Allocator&) { swapped = true; }
  46       friend bool operator==(Allocator, Allocator) { return true; }
  47     };
  48 }
  49
  50 void
  51 test_swap()
  52 {
  53   std::unordered_set<int, adl::Eq, adl::Hash, adl::Allocator<int>> s1, s2;
  54   s1.swap(s2);
  55   VERIFY( adl::Hash::swapped );
  56   VERIFY( adl::Eq::swapped );
  57   VERIFY( adl::Allocator_base::swapped );
  58 }
  59
  60 int main()
  61 {
  62   test_swap();
  63 }