libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <algorithm>
  10
  11 // template<InputIterator InIter, OutputIterator<auto, InIter::reference> OutIter>
  12 //   constexpr OutIter   // constexpr after C++17
  13 //   copy(InIter first, InIter last, OutIter result);
  14
  15 #include <algorithm>
  16 #include <cassert>
  17
  18 #include "test_macros.h"
  19 #include "test_iterators.h"
  20
  21 class PaddedBase {
  22 public:
  23   TEST_CONSTEXPR PaddedBase(std::int16_t a, std::int8_t b) : a_(a), b_(b) {}
  24
  25   std::int16_t a_;
  26   std::int8_t b_;
  27 };
  28
  29 class Derived : public PaddedBase {
  30 public:
  31   TEST_CONSTEXPR Derived(std::int16_t a, std::int8_t b, std::int8_t c) : PaddedBase(a, b), c_(c) {}
  32
  33   std::int8_t c_;
  34 };
  35
  36 template <class InIter>
  37 struct Test {
  38   template <class OutIter>
  39   TEST_CONSTEXPR_CXX20 void operator()() {
  40     const unsigned N = 1000;
  41     int ia[N]        = {};
  42     for (unsigned i = 0; i < N; ++i)
  43       ia[i] = i;
  44     int ib[N] = {0};
  45
  46     OutIter r = std::copy(InIter(ia), InIter(ia + N), OutIter(ib));
  47     assert(base(r) == ib + N);
  48     for (unsigned i = 0; i < N; ++i)
  49       assert(ia[i] == ib[i]);
  50   }
  51 };
  52
  53 struct TestInIters {
  54   template <class InIter>
  55   TEST_CONSTEXPR_CXX20 void operator()() {
  56     types::for_each(
  57         types::concatenate_t<types::cpp17_input_iterator_list<int*>, types::type_list<cpp17_output_iterator<int*> > >(),
  58         Test<InIter>());
  59   }
  60 };
  61
  62 TEST_CONSTEXPR_CXX20 bool test() {
  63   types::for_each(types::cpp17_input_iterator_list<int*>(), TestInIters());
  64
  65   { // Make sure that padding bits aren't copied
  66     Derived src(1, 2, 3);
  67     Derived dst(4, 5, 6);
  68     std::copy(static_cast<PaddedBase*>(&src), static_cast<PaddedBase*>(&src) + 1, static_cast<PaddedBase*>(&dst));
  69     assert(dst.a_ == 1);
  70     assert(dst.b_ == 2);
  71     assert(dst.c_ == 6);
  72   }
  73
  74   { // Make sure that overlapping ranges can be copied
  75     int a[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
  76     std::copy(a + 3, a + 10, a);
  77     int expected[] = {4, 5, 6, 7, 8, 9, 10, 8, 9, 10};
  78     assert(std::equal(a, a + 10, expected));
  79   }
  80
  81   return true;
  82 }
  83
  84 int main(int, char**) {
  85   test();
  86
  87 #if TEST_STD_VER > 17
  88   static_assert(test());
  89 #endif
  90
  91   return 0;
  92 }