1 // Copyright (C) 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-do run { target c++14 } }
19
20 #include <charconv>
21 #include <string>
22 #include <testsuite_hooks.h>
23
24 #ifdef DEBUG
25 #include <stdio.h>
26 #endif
27
28 long long
read(const char * first,const char * last,int base)29 read(const char* first, const char* last, int base)
30 {
31 long long val = 0;
32 unsigned long long place = 1;
33 while (last > first)
34 {
35 val += (*--last - '0') * place;
36 place *= base;
37 }
38 return val;
39 }
40
41 void
test01()42 test01()
43 {
44 std::from_chars_result res;
45 long long val;
46 for (auto s : { "10001", "10010", "10011", "10101", "10110", "10111",
47 "11001", "11010", "11011", "11101", "11110", "11111" })
48 {
49 std::string ss[2] = { s, std::string(64, '0') + s };
50 for (const auto& str : ss)
51 {
52 const char* first = str.data();
53 for (int base = 2; base < 37; ++base)
54 {
55 const char* last = str.data() + str.length();
56 for (size_t n = 0; n < ss[0].length(); ++n)
57 {
58 #ifdef DEBUG
59 printf("Parsing \"%.*s\" in base %d\n", int(last - first), first,
60 base);
61 #endif
62 res = std::from_chars(first, last, val, base);
63 VERIFY( res.ptr == last );
64 VERIFY( res.ec == std::errc{} );
65 VERIFY( val == read(first, last, base) );
66 // Test again with shorter string to check from_chars doesn't read
67 // the digits past the last pointer.
68 --last;
69 }
70 }
71 }
72 }
73 }
74
75 int
main()76 main()
77 {
78 test01();
79 }
80