tests/test-wcscmp.c

   1 /* Test of wcscmp() function.
   2    Copyright (C) 2010-2024 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>, 2023.  */
  18
  19 #include <config.h>
  20
  21 #include <wchar.h>
  22
  23 #include "signature.h"
  24 SIGNATURE_CHECK (wcscmp, int, (const wchar_t *, const wchar_t *));
  25
  26 #include "macros.h"
  27
  28 int
  29 main (int argc, char *argv[])
  30 {
  31   /* Test simple cases.  */
  32   {
  33     static const wchar_t input1[] = { 0 };
  34     static const wchar_t input2[] = { 0 };
  35     ASSERT (wcscmp (input1, input2) == 0);
  36   }
  37   {
  38     static const wchar_t input1[] = { 0 };
  39     static const wchar_t input2[] = { 'f', 'o', 'o', 0 };
  40     ASSERT (wcscmp (input1, input2) < 0);
  41     ASSERT (wcscmp (input2, input1) > 0);
  42   }
  43   {
  44     static const wchar_t input1[] = { 'f', 'o', 'o', 0 };
  45     static const wchar_t input2[] = { 'f', 'o', 'o', 0 };
  46     ASSERT (wcscmp (input1, input2) == 0);
  47   }
  48   {
  49     static const wchar_t input1[] = { 'f', 'o', 'o', 0 };
  50     static const wchar_t input2[] = { 'b', 'a', 'r', 0 };
  51     ASSERT (wcscmp (input1, input2) > 0);
  52     ASSERT (wcscmp (input2, input1) < 0);
  53   }
  54   {
  55     static const wchar_t input1[] = { 'f', 'o', 'o', 0 };
  56     static const wchar_t input2[] = { 'f', 'o', 'o', 'b', 'a', 'r', 0 };
  57     ASSERT (wcscmp (input1, input2) < 0);
  58     ASSERT (wcscmp (input2, input1) > 0);
  59   }
  60   {
  61     static const wchar_t input1[] = { 'o', 'o', 'm', 'p', 'h', 0 };
  62     static const wchar_t input2[] = { 'o', 'o', 'p', 's', 0 };
  63     ASSERT (wcscmp (input1, input2) < 0);
  64     ASSERT (wcscmp (input2, input1) > 0);
  65   }
  66
  67   /* ISO C requires wcscmp to work with all wchar_t values.
  68      ISO C 17 § 7.29.4.4 says:
  69        "Unless explicitly stated otherwise, the functions described in this
  70         subclause order two wide characters the same way as two integers of
  71         the underlying integer type designated by wchar_t."  */
  72   {
  73     static const wchar_t input1[] = { (wchar_t) 0x76547654, 0 };
  74     static const wchar_t input2[] = { (wchar_t) 0x9abc9abc, 0 };
  75     if ((wchar_t)-1 < 0)
  76       {
  77         /* wchar_t is signed.  */
  78         ASSERT (wcscmp (input1, input2) > 0);
  79         ASSERT (wcscmp (input2, input1) < 0);
  80       }
  81     else
  82       {
  83         /* wchar_t is unsigned.  */
  84         ASSERT (wcscmp (input1, input2) < 0);
  85         ASSERT (wcscmp (input2, input1) > 0);
  86       }
  87   }
  88   {
  89     static const wchar_t input1[] = { (wchar_t) 0x9abc9abc, 0 };
  90     static const wchar_t input2[] = { (wchar_t) 0x9bdf9bdf, 0 };
  91     ASSERT (wcscmp (input1, input2) < 0);
  92     ASSERT (wcscmp (input2, input1) > 0);
  93   }
  94
  95   /* Comparing a negative wchar_t value against a null wchar_t.
  96      ISO C 17 § 7.29.4.4.1 says:
  97        "The wcscmp function compares the wide string pointed to by s1 to
  98         the wide string pointed to by s2."
  99      ISO C 17 § 7.1.1 defines the term "wide string":
 100        "A wide string is a contiguous sequence of wide characters terminated
 101         by and including the first null wide character."
 102      This means that the comparison extends up to and *including* the first
 103      null wchar_t.  */
 104   {
 105     static const wchar_t input1[] = { (wchar_t) 'x', 0 };
 106     static const wchar_t input2[] = { (wchar_t) 'x', (wchar_t) 0x9abc9abc, 0 };
 107     if ((wchar_t)-1 < 0)
 108       {
 109         /* wchar_t is signed.  */
 110         ASSERT (wcscmp (input1, input2) > 0);
 111         ASSERT (wcscmp (input2, input1) < 0);
 112       }
 113     else
 114       {
 115         /* wchar_t is unsigned.  */
 116         ASSERT (wcscmp (input1, input2) < 0);
 117         ASSERT (wcscmp (input2, input1) > 0);
 118       }
 119   }
 120
 121   return test_exit_status;
 122 }