libcxx/test/std/strings/strings.erasure/erase.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 // UNSUPPORTED: c++03, c++11, c++14, c++17
   9
  10 // <string>
  11
  12 // template <class charT, class traits, class Allocator, class U>
  13 //   typename basic_string<charT, traits, Allocator>::size_type
  14 //   erase(basic_string<charT, traits, Allocator>& c, const U& value);
  15
  16 #include <string>
  17 #include <optional>
  18
  19 #include "test_macros.h"
  20 #include "test_allocator.h"
  21 #include "min_allocator.h"
  22
  23 template <class S, class U>
  24 void test0(S s, U val, S expected, size_t expected_erased_count) {
  25   ASSERT_SAME_TYPE(typename S::size_type, decltype(std::erase(s, val)));
  26   assert(expected_erased_count == std::erase(s, val));
  27   LIBCPP_ASSERT(s.__invariants());
  28   assert(s == expected);
  29 }
  30
  31 template <class S>
  32 void test()
  33 {
  34
  35   test0(S(""), 'a', S(""), 0);
  36
  37   test0(S("a"), 'a', S(""), 1);
  38   test0(S("a"), 'b', S("a"), 0);
  39
  40   test0(S("ab"), 'a', S("b"), 1);
  41   test0(S("ab"), 'b', S("a"), 1);
  42   test0(S("ab"), 'c', S("ab"), 0);
  43   test0(S("aa"), 'a', S(""), 2);
  44   test0(S("aa"), 'c', S("aa"), 0);
  45
  46   test0(S("abc"), 'a', S("bc"), 1);
  47   test0(S("abc"), 'b', S("ac"), 1);
  48   test0(S("abc"), 'c', S("ab"), 1);
  49   test0(S("abc"), 'd', S("abc"), 0);
  50
  51   test0(S("aab"), 'a', S("b"), 2);
  52   test0(S("aab"), 'b', S("aa"), 1);
  53   test0(S("aab"), 'c', S("aab"), 0);
  54   test0(S("abb"), 'a', S("bb"), 1);
  55   test0(S("abb"), 'b', S("a"), 2);
  56   test0(S("abb"), 'c', S("abb"), 0);
  57   test0(S("aaa"), 'a', S(""), 3);
  58   test0(S("aaa"), 'b', S("aaa"), 0);
  59
  60   //  Test cross-type erasure
  61   using opt = std::optional<typename S::value_type>;
  62   test0(S("aba"), opt(), S("aba"), 0);
  63   test0(S("aba"), opt('a'), S("b"), 2);
  64   test0(S("aba"), opt('b'), S("aa"), 1);
  65   test0(S("aba"), opt('c'), S("aba"), 0);
  66 }
  67
  68 int main(int, char**)
  69 {
  70     test<std::string>();
  71     test<std::basic_string<char, std::char_traits<char>, min_allocator<char>>> ();
  72     test<std::basic_string<char, std::char_traits<char>, test_allocator<char>>> ();
  73
  74   return 0;
  75 }