libstdc++-v3/testsuite/25_algorithms/lower_bound/partitioned.cc

   1 // Copyright (C) 2016-2020 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-D_GLIBCXX_DEBUG" }
  19 // { dg-do run { target c++11 } }
  20 // { dg-skip-if "" { *-*-* } { "-D_GLIBCXX_PARALLEL" } }
  21
  22 #include <algorithm>
  23 #include <functional>
  24 #include <testsuite_iterators.h>
  25 #include <testsuite_hooks.h>
  26
  27 using __gnu_test::test_container;
  28 using __gnu_test::forward_iterator_wrapper;
  29
  30 struct X
  31 {
  32   int val;
  33
  34   bool odd() const { return val % 2; }
  35
  36   // Partitioned so that all odd values come before even values:
  37   bool operator<(const X& x) const { return this->odd() && !x.odd(); }
  38 };
  39
  40 void
  41 test01()
  42 {
  43   // Test with range that is partitioned, but not sorted.
  44   X seq[] = { 1, 3, 5, 7, 1, 6, 4, 2 };
  45   test_container<X, forward_iterator_wrapper> c(seq);
  46
  47   auto part1 = std::lower_bound(c.begin(), c.end(), X{2});
  48   VERIFY( part1 != c.end() );
  49   VERIFY( part1->val == 6 );
  50   auto part2 = std::lower_bound(c.begin(), c.end(), X{2}, std::less<X>{});
  51   VERIFY( part2 != c.end() );
  52   VERIFY( part2->val == 6 );
  53
  54   auto part3 = std::lower_bound(c.begin(), c.end(), X{9});
  55   VERIFY( part3 != c.end() );
  56   VERIFY( part3->val == 1 );
  57   auto part4 = std::lower_bound(c.begin(), c.end(), X{9}, std::less<X>{});
  58   VERIFY( part4 != c.end() );
  59   VERIFY( part4->val == 1 );
  60 }
  61
  62 struct Y
  63 {
  64   double val;
  65
  66   // Not irreflexive, so not a strict weak order.
  67   bool operator<(const Y& y) const { return val < int(y.val); }
  68 };
  69
  70 void
  71 test02()
  72 {
  73   // Test that Debug Mode checks don't fire (libstdc++/71545)
  74
  75   Y seq[] = { -0.1, 1.2, 5.0, 5.2, 5.1, 5.9, 5.5, 6.0 };
  76   test_container<Y, forward_iterator_wrapper> c(seq);
  77
  78   auto part1 = std::lower_bound(c.begin(), c.end(), Y{5.5});
  79   VERIFY( part1 != c.end() );
  80   VERIFY( part1->val == 5.0 );
  81   auto part2 = std::lower_bound(c.begin(), c.end(), Y{5.5}, std::less<Y>{});
  82   VERIFY( part2 != c.end() );
  83   VERIFY( part2->val == 5.0 );
  84
  85   auto part3 = std::lower_bound(c.begin(), c.end(), Y{1.0});
  86   VERIFY( part3 != c.end() );
  87   VERIFY( part3->val == 1.2 );
  88   auto part4 = std::lower_bound(c.begin(), c.end(), Y{1.0}, std::less<Y>{});
  89   VERIFY( part4 != c.end() );
  90   VERIFY( part4->val == 1.2 );
  91 }
  92
  93 int
  94 main()
  95 {
  96   test01();
  97   test02();
  98 }