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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_view>
// constexpr basic_string_view substr(size_type pos = 0, size_type n = npos) const;
// Throws: out_of_range if pos > size().
// Effects: Determines the effective length rlen of the string to reference as the smaller of n and size() - pos.
// Returns: basic_string_view(data()+pos, rlen).
#include <string_view>
#include <algorithm>
#include <stdexcept>
#include <cassert>
#include "test_macros.h"
template<typename CharT>
void test1(std::basic_string_view<CharT> sv, size_t n, size_t pos) {
std::basic_string_view<CharT> sv1;
#ifdef TEST_HAS_NO_EXCEPTIONS
if (pos > sv.size())
return ; // would throw if exceptions were enabled
sv1 = sv.substr(pos, n);
#else
try {
sv1 = sv.substr(pos, n);
assert(pos <= sv.size());
}
catch (const std::out_of_range&) {
assert(pos > sv.size());
return ;
}
#endif
const size_t rlen = std::min(n, sv.size() - pos);
assert (sv1.size() == rlen);
for (size_t i = 0; i < rlen; ++i)
assert(sv[pos+i] == sv1[i]);
}
template<typename CharT>
void test ( const CharT *s ) {
typedef std::basic_string_view<CharT> string_view_t;
string_view_t sv1 ( s );
test1(sv1, 0, 0);
test1(sv1, 1, 0);
test1(sv1, 20, 0);
test1(sv1, sv1.size(), 0);
test1(sv1, 0, 3);
test1(sv1, 2, 3);
test1(sv1, 100, 3);
test1(sv1, 0, string_view_t::npos);
test1(sv1, 2, string_view_t::npos);
test1(sv1, sv1.size(), string_view_t::npos);
test1(sv1, sv1.size() + 1, 0);
test1(sv1, sv1.size() + 1, 1);
test1(sv1, sv1.size() + 1, string_view_t::npos);
}
int main(int, char**) {
test ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
test ( "ABCDE");
test ( "a" );
test ( "" );
test ( L"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
test ( L"ABCDE" );
test ( L"a" );
test ( L"" );
#if TEST_STD_VER >= 11
test ( u"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
test ( u"ABCDE" );
test ( u"a" );
test ( u"" );
test ( U"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE" );
test ( U"ABCDE" );
test ( U"a" );
test ( U"" );
#endif
#if TEST_STD_VER > 11
{
constexpr std::string_view sv1 { "ABCDE", 5 };
{
constexpr std::string_view sv2 = sv1.substr ( 0, 3 );
static_assert ( sv2.size() == 3, "" );
static_assert ( sv2[0] == 'A', "" );
static_assert ( sv2[1] == 'B', "" );
static_assert ( sv2[2] == 'C', "" );
}
{
constexpr std::string_view sv2 = sv1.substr ( 3, 0 );
static_assert ( sv2.size() == 0, "" );
}
{
constexpr std::string_view sv2 = sv1.substr ( 3, 3 );
static_assert ( sv2.size() == 2, "" );
static_assert ( sv2[0] == 'D', "" );
static_assert ( sv2[1] == 'E', "" );
}
}
#endif
return 0;
}
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