libstdc++-v3/testsuite/20_util/from_chars/1.cc

   1 // Copyright (C) 2017-2020 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 "-std=gnu++17" }
  19 // { dg-do run { target c++17 } }
  20
  21 #include <charconv>
  22 #include <string_view>
  23
  24 template<typename I>
  25 bool
  26 check_from_chars(I expected, std::string_view s, int base = 0, char term = '\0')
  27 {
  28   I val;
  29   std::from_chars_result r = base == 0
  30     ? std::from_chars(s.begin(), s.end(), val)
  31     : std::from_chars(s.begin(), s.end(), val, base);
  32   return r.ec == std::errc{} && (r.ptr == s.end() || *r.ptr == term) && val == expected;
  33 }
  34
  35 #include <climits>
  36 #include <testsuite_hooks.h>
  37
  38 void
  39 test01()
  40 {
  41   // Using base 10
  42   VERIFY( check_from_chars(123, "123") );
  43   VERIFY( check_from_chars(-123, "-123") );
  44   VERIFY( check_from_chars(123, "123a", 10, 'a') );
  45   VERIFY( check_from_chars(123, "0000000000000000000000000000123") );
  46   VERIFY( check_from_chars(123, "0000000000000000000000000000123a", 10, 'a') );
  47 }
  48
  49 void
  50 test02()
  51 {
  52   // "0x" parsed as "0" not as hex prefix:
  53   VERIFY( check_from_chars(0, "0x1", 10, 'x') );
  54   VERIFY( check_from_chars(0, "0X1", 10, 'X') );
  55   VERIFY( check_from_chars(0, "0x1", 16, 'x') );
  56   VERIFY( check_from_chars(0, "0X1", 16, 'X') );
  57
  58   VERIFY( check_from_chars(1155, "xx", 34) );
  59   VERIFY( check_from_chars(1155, "XX", 34) );
  60   VERIFY( check_from_chars(1155, "Xx", 34) );
  61   VERIFY( check_from_chars(1224, "yy", 35) );
  62   VERIFY( check_from_chars(1224, "YY", 35) );
  63   VERIFY( check_from_chars(1224, "yY", 35) );
  64   VERIFY( check_from_chars(1295, "zz", 36) );
  65   VERIFY( check_from_chars(1295, "ZZ", 36) );
  66   VERIFY( check_from_chars(1295, "Zz", 36) );
  67
  68   // Parsing stops at first invalid digit for the given base:
  69   VERIFY( check_from_chars(1, "01234", 2, '2') );
  70   VERIFY( check_from_chars(27, "1234", 4, '4') );
  71   VERIFY( check_from_chars(1155, "xxy", 34, 'y') );
  72   VERIFY( check_from_chars(1224, "yyz", 35, 'z') );
  73 }
  74
  75 int
  76 main()
  77 {
  78   test01();
  79   test02();
  80 }