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//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
// <string>
// template<class charT, class traits, class Allocator>
// basic_string<charT,traits,Allocator>
// operator+(const charT* lhs, const basic_string<charT,traits,Allocator>& rhs); // constexpr since C++20
// template<class charT, class traits, class Allocator>
// basic_string<charT,traits,Allocator>&&
// operator+(const charT* lhs, basic_string<charT,traits,Allocator>&& rhs); // constexpr since C++20
#include <cassert>
#include <string>
#include <utility>
#include "test_macros.h"
#include "min_allocator.h"
template <class S>
TEST_CONSTEXPR_CXX20 void test_string() {
const char* test_data[2][4] = {
{"", "abcde", "abcdefghij", "abcdefghijklmnopqrst"}, {"", "12345", "1234567890", "12345678901234567890"}};
const char* results[4][4] = {
{"", "12345", "1234567890", "12345678901234567890"},
{"abcde", "abcde12345", "abcde1234567890", "abcde12345678901234567890"},
{"abcdefghij", "abcdefghij12345", "abcdefghij1234567890", "abcdefghij12345678901234567890"},
{"abcdefghijklmnopqrst",
"abcdefghijklmnopqrst12345",
"abcdefghijklmnopqrst1234567890",
"abcdefghijklmnopqrst12345678901234567890"}};
for (size_t i = 0; i != 4; ++i) {
for (size_t k = 0; k != 4; ++k) {
{ // operator+(const value_type*, const string&);
const char* lhs = test_data[0][i];
const S rhs(test_data[1][k]);
assert(lhs + rhs == results[i][k]);
}
#if TEST_STD_VER >= 11
{ // operator+(const value_type*, string&&);
const char* lhs = test_data[0][i];
S rhs(test_data[1][k]);
assert(lhs + std::move(rhs) == results[i][k]);
}
#endif
}
}
}
TEST_CONSTEXPR_CXX20 bool test() {
test_string<std::string>();
#if TEST_STD_VER >= 11
test_string<std::basic_string<char, std::char_traits<char>, min_allocator<char>>>();
#endif
{ // check that growing to max_size() works
using string_type = std::basic_string<char, std::char_traits<char>, tiny_size_allocator<29, char> >;
string_type str;
str.resize(str.max_size() - 1);
string_type result = "a" + str;
assert(result.size() == result.max_size());
assert(result.front() == 'a');
assert(result.capacity() <= result.get_allocator().max_size());
}
return true;
}
int main(int, char**) {
test();
#if TEST_STD_VER >= 20
static_assert(test());
#endif
return 0;
}
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