tests/test-wcwidth.c

   1 /* Test of wcwidth() function.
   2    Copyright (C) 2007-2024 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2007.  */
  18
  19 #include <config.h>
  20
  21 #include <wchar.h>
  22
  23 #include "signature.h"
  24 SIGNATURE_CHECK (wcwidth, int, (wchar_t));
  25
  26 #include <locale.h>
  27 #include <string.h>
  28
  29 #include "c-ctype.h"
  30 #include "localcharset.h"
  31 #include "macros.h"
  32
  33 int
  34 main ()
  35 {
  36   wchar_t wc;
  37
  38 #if !GNULIB_WCHAR_SINGLE_LOCALE
  39 # ifdef C_CTYPE_ASCII
  40   /* Test width of ASCII characters.  */
  41   for (wc = 0x20; wc < 0x7F; wc++)
  42     ASSERT (wcwidth (wc) == 1);
  43 # endif
  44 #endif
  45
  46   /* Switch to an UTF-8 locale.  */
  47   if (setlocale (LC_ALL, "fr_FR.UTF-8") != NULL
  48       /* Check whether it's really an UTF-8 locale.
  49          On OpenBSD 4.0, the setlocale call succeeds only for the LC_CTYPE
  50          category and therefore returns "C/fr_FR.UTF-8/C/C/C/C", but the
  51          LC_CTYPE category is effectively set to an ASCII LC_CTYPE category;
  52          in particular, locale_charset() returns "ASCII".  */
  53       && strcmp (locale_charset (), "UTF-8") == 0)
  54     {
  55       /* Test width of ASCII characters.  */
  56       for (wc = 0x20; wc < 0x7F; wc++)
  57         ASSERT (wcwidth (wc) == 1);
  58
  59       /* Test width of some non-spacing characters.  */
  60       ASSERT (wcwidth (0x0301) == 0);
  61       ASSERT (wcwidth (0x05B0) == 0);
  62
  63       /* Test width of some format control characters.  */
  64       ASSERT (wcwidth (0x200E) <= 0);
  65       ASSERT (wcwidth (0x2060) <= 0);
  66 #if 0  /* wchar_t may be only 16 bits.  */
  67       ASSERT (wcwidth (0xE0001) <= 0);
  68       ASSERT (wcwidth (0xE0044) <= 0);
  69 #endif
  70
  71       /* Test width of some zero width characters.  */
  72       /* While it is desirable that U+200B, U+200C, U+200D have width 0,
  73          because this makes wcswidth work better on strings that contain these
  74          characters, it is acceptable if an implementation treats these
  75          characters like control characters.  */
  76       ASSERT (wcwidth (0x200B) <= 0);
  77       ASSERT (wcwidth (0xFEFF) <= 0);
  78
  79       /* Test width of some math symbols.
  80          U+2202 is marked as having ambiguous width (A) in EastAsianWidth.txt
  81          (see <https://www.unicode.org/Public/12.0.0/ucd/EastAsianWidth.txt>).
  82          The Unicode Standard Annex 11
  83          <https://www.unicode.org/reports/tr11/tr11-36.html>
  84          says
  85            "Ambiguous characters behave like wide or narrow characters
  86             depending on the context (language tag, script identification,
  87             associated font, source of data, or explicit markup; all can
  88             provide the context). If the context cannot be established
  89             reliably, they should be treated as narrow characters by default."
  90          For wcwidth(), the only available context information is the locale.
  91          "fr_FR.UTF-8" is a Western locale, not an East Asian locale, therefore
  92          U+2202 should be treated like a narrow character.  */
  93       ASSERT (wcwidth (0x2202) == 1);
  94
  95       /* Test width of some CJK characters.  */
  96       ASSERT (wcwidth (0x3000) == 2);
  97       ASSERT (wcwidth (0xB250) == 2);
  98       ASSERT (wcwidth (0xFF1A) == 2);
  99 #if 0  /* wchar_t may be only 16 bits.  */
 100       ASSERT (wcwidth (0x20369) == 2);
 101       ASSERT (wcwidth (0x2F876) == 2);
 102 #endif
 103     }
 104
 105   return test_exit_status;
 106 }