libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/partition_point.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<class ForwardIterator, class Predicate>
  12 //     constexpr ForwardIterator       // constexpr after C++17
  13 //     partition_point(ForwardIterator first, ForwardIterator last, Predicate pred);
  14
  15 #include <algorithm>
  16 #include <cassert>
  17
  18 #include "test_macros.h"
  19 #include "test_iterators.h"
  20
  21 struct is_odd
  22 {
  23     TEST_CONSTEXPR bool operator()(const int& i) const {return i & 1;}
  24 };
  25
  26
  27 #if TEST_STD_VER > 17
  28 TEST_CONSTEXPR bool test_constexpr() {
  29     int ia[] = {1, 3, 5, 2, 4, 6};
  30     int ib[] = {1, 2, 3, 4, 5, 6};
  31     return    (std::partition_point(std::begin(ia), std::end(ia), is_odd()) == ia+3)
  32            && (std::partition_point(std::begin(ib), std::end(ib), is_odd()) == ib+1)
  33            ;
  34     }
  35 #endif
  36
  37
  38 int main(int, char**)
  39 {
  40     {
  41         const int ia[] = {2, 4, 6, 8, 10};
  42         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  43                                     forward_iterator<const int*>(std::end(ia)),
  44                                     is_odd()) == forward_iterator<const int*>(ia));
  45     }
  46     {
  47         const int ia[] = {1, 2, 4, 6, 8};
  48         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  49                                     forward_iterator<const int*>(std::end(ia)),
  50                                     is_odd()) == forward_iterator<const int*>(ia + 1));
  51     }
  52     {
  53         const int ia[] = {1, 3, 2, 4, 6};
  54         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  55                                     forward_iterator<const int*>(std::end(ia)),
  56                                     is_odd()) == forward_iterator<const int*>(ia + 2));
  57     }
  58     {
  59         const int ia[] = {1, 3, 5, 2, 4, 6};
  60         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  61                                     forward_iterator<const int*>(std::end(ia)),
  62                                     is_odd()) == forward_iterator<const int*>(ia + 3));
  63     }
  64     {
  65         const int ia[] = {1, 3, 5, 7, 2, 4};
  66         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  67                                     forward_iterator<const int*>(std::end(ia)),
  68                                     is_odd()) == forward_iterator<const int*>(ia + 4));
  69     }
  70     {
  71         const int ia[] = {1, 3, 5, 7, 9, 2};
  72         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  73                                     forward_iterator<const int*>(std::end(ia)),
  74                                     is_odd()) == forward_iterator<const int*>(ia + 5));
  75     }
  76     {
  77         const int ia[] = {1, 3, 5, 7, 9, 11};
  78         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  79                                     forward_iterator<const int*>(std::end(ia)),
  80                                     is_odd()) == forward_iterator<const int*>(ia + 6));
  81     }
  82     {
  83         const int ia[] = {1, 3, 5, 2, 4, 6, 7};
  84         assert(std::partition_point(forward_iterator<const int*>(std::begin(ia)),
  85                                     forward_iterator<const int*>(std::begin(ia)),
  86                                     is_odd()) == forward_iterator<const int*>(ia));
  87     }
  88
  89 #if TEST_STD_VER > 17
  90     static_assert(test_constexpr());
  91 #endif
  92
  93   return 0;
  94 }