text: //===----------------------------------------------------------------------===//
  //
  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  // See https://llvm.org/LICENSE.txt for license information.
  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  //
  //===----------------------------------------------------------------------===//
  
  // <unordered_map>
  
  // template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
  //           class Alloc = allocator<pair<const Key, T>>>
  // class unordered_map
  
  // unordered_map(unordered_map&& u);
  
  // UNSUPPORTED: c++98, c++03
  
  #include <unordered_map>
  #include <string>
  #include <cassert>
  #include <cfloat>
  #include <cmath>
  #include <cstddef>
  
  #include "test_macros.h"
  #include "../../../test_compare.h"
  #include "../../../test_hash.h"
  #include "test_allocator.h"
  #include "min_allocator.h"
  
  int main(int, char**)
  {
      {
          typedef std::unordered_map<int, std::string,
                                     test_hash<std::hash<int> >,
                                     test_compare<std::equal_to<int> >,
                                     test_allocator<std::pair<const int, std::string> >
                                     > C;
          C c0(7,
              test_hash<std::hash<int> >(8),
              test_compare<std::equal_to<int> >(9),
              test_allocator<std::pair<const int, std::string> >(10)
             );
          C c = std::move(c0);
          LIBCPP_ASSERT(c.bucket_count() == 7);
          assert(c.size() == 0);
          assert(c.hash_function() == test_hash<std::hash<int> >(8));
          assert(c.key_eq() == test_compare<std::equal_to<int> >(9));
          assert(c.get_allocator() ==
                 (test_allocator<std::pair<const int, std::string> >(10)));
          assert(c.empty());
          assert(static_cast<std::size_t>(std::distance(c.begin(), c.end())) == c.size());
          assert(static_cast<std::size_t>(std::distance(c.cbegin(), c.cend())) == c.size());
          assert(c.load_factor() == 0);
          assert(c.max_load_factor() == 1);
  
          assert(c0.empty());
      }
      {
          typedef std::unordered_map<int, std::string,
                                     test_hash<std::hash<int> >,
                                     test_compare<std::equal_to<int> >,
                                     test_allocator<std::pair<const int, std::string> >
                                     > C;
          typedef std::pair<int, std::string> P;
          P a[] =
          {
              P(1, "one"),
              P(2, "two"),
              P(3, "three"),
              P(4, "four"),
              P(1, "four"),
              P(2, "four"),
          };
          C c0(a, a + sizeof(a)/sizeof(a[0]),
              7,
              test_hash<std::hash<int> >(8),
              test_compare<std::equal_to<int> >(9),
              test_allocator<std::pair<const int, std::string> >(10)
             );
          C c = std::move(c0);
          LIBCPP_ASSERT(c.bucket_count() == 7);
          assert(c.size() == 4);
          assert(c.at(1) == "one");
          assert(c.at(2) == "two");
          assert(c.at(3) == "three");
          assert(c.at(4) == "four");
          assert(c.hash_function() == test_hash<std::hash<int> >(8));
          assert(c.key_eq() == test_compare<std::equal_to<int> >(9));
          assert(c.get_allocator() ==
                 (test_allocator<std::pair<const int, std::string> >(10)));
          assert(!c.empty());
          assert(static_cast<std::size_t>(std::distance(c.begin(), c.end())) == c.size());
          assert(static_cast<std::size_t>(std::distance(c.cbegin(), c.cend())) == c.size());
          assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
          assert(c.max_load_factor() == 1);
  
          assert(c0.empty());
      }
      {
          typedef std::unordered_map<int, std::string,
                                     test_hash<std::hash<int> >,
                                     test_compare<std::equal_to<int> >,
                                     min_allocator<std::pair<const int, std::string> >
                                     > C;
          C c0(7,
              test_hash<std::hash<int> >(8),
              test_compare<std::equal_to<int> >(9),
              min_allocator<std::pair<const int, std::string> >()
             );
          C c = std::move(c0);
          LIBCPP_ASSERT(c.bucket_count() == 7);
          assert(c.size() == 0);
          assert(c.hash_function() == test_hash<std::hash<int> >(8));
          assert(c.key_eq() == test_compare<std::equal_to<int> >(9));
          assert(c.get_allocator() ==
                 (min_allocator<std::pair<const int, std::string> >()));
          assert(c.empty());
          assert(static_cast<std::size_t>(std::distance(c.begin(), c.end())) == c.size());
          assert(static_cast<std::size_t>(std::distance(c.cbegin(), c.cend())) == c.size());
          assert(c.load_factor() == 0);
          assert(c.max_load_factor() == 1);
  
          assert(c0.empty());
      }
      {
          typedef std::unordered_map<int, std::string,
                                     test_hash<std::hash<int> >,
                                     test_compare<std::equal_to<int> >,
                                     min_allocator<std::pair<const int, std::string> >
                                     > C;
          typedef std::pair<int, std::string> P;
          P a[] =
          {
              P(1, "one"),
              P(2, "two"),
              P(3, "three"),
              P(4, "four"),
              P(1, "four"),
              P(2, "four"),
          };
          C c0(a, a + sizeof(a)/sizeof(a[0]),
              7,
              test_hash<std::hash<int> >(8),
              test_compare<std::equal_to<int> >(9),
              min_allocator<std::pair<const int, std::string> >()
             );
          C c = std::move(c0);
          LIBCPP_ASSERT(c.bucket_count() == 7);
          assert(c.size() == 4);
          assert(c.at(1) == "one");
          assert(c.at(2) == "two");
          assert(c.at(3) == "three");
          assert(c.at(4) == "four");
          assert(c.hash_function() == test_hash<std::hash<int> >(8));
          assert(c.key_eq() == test_compare<std::equal_to<int> >(9));
          assert(c.get_allocator() ==
                 (min_allocator<std::pair<const int, std::string> >()));
          assert(!c.empty());
          assert(static_cast<std::size_t>(std::distance(c.begin(), c.end())) == c.size());
          assert(static_cast<std::size_t>(std::distance(c.cbegin(), c.cend())) == c.size());
          assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
          assert(c.max_load_factor() == 1);
  
          assert(c0.empty());
      }
  #if _LIBCPP_DEBUG >= 1
      {
          std::unordered_map<int, int> s1 = {{1, 1}, {2, 2}, {3, 3}};
          std::unordered_map<int, int>::iterator i = s1.begin();
          std::pair<const int, int> k = *i;
          std::unordered_map<int, int> s2 = std::move(s1);
          assert(*i == k);
          s2.erase(i);
          assert(s2.size() == 2);
      }
  #endif
  
    return 0;
  }
  