--- /dev/null
+/* Test <mcel.h>
+ Copyright 2023 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include <mcel.h>
+
+#include <locale.h>
+
+#include "macros.h"
+
+static wint_t
+to_ascii (wint_t c)
+{
+ return c & 0x7f;
+}
+
+static int
+sgn (int i)
+{
+ return (i > 0) - (i < 0);
+}
+
+static void
+test_mcel_vs_mbrtoc32 (unsigned char uc, mcel_t c, size_t n, char32_t ch)
+{
+ ASSERT (!c.err == (n <= MB_LEN_MAX));
+ ASSERT (c.err
+ ? c.err == uc && c.ch == 0 && c.len == 1
+ : c.ch == ch && c.len == (n ? n : 1));
+}
+
+int
+main (void)
+{
+ /* configure should already have checked that the locale is supported. */
+ if (setlocale (LC_ALL, "") == NULL)
+ return 1;
+
+ mcel_t prev;
+ for (int ch = 0; ch < 0x80; ch++)
+ {
+ mcel_t c = mcel_ch (ch, 1);
+ ASSERT (c.ch == ch);
+ ASSERT (c.len == 1);
+ ASSERT (!c.err);
+ ASSERT (mcel_cmp (c, c) == 0);
+ ASSERT (mcel_tocmp (to_ascii, c, c) == 0);
+ if (ch)
+ {
+ ASSERT (mcel_cmp (prev, c) < 0);
+ ASSERT (mcel_cmp (c, prev) > 0);
+ ASSERT (mcel_tocmp (to_ascii, prev, c) < 0);
+ ASSERT (mcel_tocmp (to_ascii, c, prev) > 0);
+ }
+ ASSERT (mcel_isbasic (ch));
+ prev = c;
+ }
+ for (char ch = CHAR_MIN; ; ch++)
+ {
+ ASSERT (mcel_isbasic (ch) == (0 <= ch && ch <= 0x7f));
+ if (ch == CHAR_MAX)
+ break;
+ }
+ for (int ch = 0x80; ch < 0x200; ch++)
+ {
+ mcel_t c = mcel_ch (ch, 2);
+ ASSERT (c.ch == ch);
+ ASSERT (c.len == 2);
+ ASSERT (!c.err);
+ ASSERT (mcel_cmp (c, c) == 0);
+ ASSERT (mcel_tocmp (to_ascii, c, c) == 0);
+ ASSERT (mcel_cmp (prev, c) < 0);
+ ASSERT (mcel_cmp (c, prev) > 0);
+ ASSERT (mcel_tocmp (to_ascii, c, c) == 0);
+ int cmp = to_ascii (c.ch) ? -1 : 1;
+ ASSERT (sgn (mcel_tocmp (to_ascii, prev, c)) == cmp);
+ ASSERT (sgn (mcel_tocmp (to_ascii, c, prev)) == -cmp);
+ prev = c;
+ }
+ for (unsigned char err = 0x80; ; err++)
+ {
+ mcel_t c = mcel_err (err);
+ ASSERT (!c.ch);
+ ASSERT (c.len == 1);
+ ASSERT (c.err == err);
+ ASSERT (mcel_cmp (c, c) == 0);
+ ASSERT (mcel_cmp (prev, c) < 0);
+ ASSERT (mcel_cmp (c, prev) > 0);
+ ASSERT (mcel_tocmp (to_ascii, c, c) == 0);
+ ASSERT (mcel_tocmp (to_ascii, prev, c) < 0);
+ ASSERT (mcel_tocmp (to_ascii, c, prev) > 0);
+ prev = c;
+ if (err == (unsigned char) -1)
+ break;
+ }
+
+ for (int i = CHAR_MIN; i <= CHAR_MAX; i++)
+ for (int j = CHAR_MIN; i <= CHAR_MAX; i++)
+ for (int k = CHAR_MIN; k <= CHAR_MAX; k++)
+ {
+ char const ijk[] = {i, j, k};
+ mbstate_t mbs = {0};
+ char32_t ch;
+ size_t n = mbrtoc32 (&ch, ijk, sizeof ijk, &mbs);
+ mcel_t c = mcel_scan (ijk, ijk + sizeof ijk);
+ test_mcel_vs_mbrtoc32 (i, c, n, ch);
+
+ static char const terminator[] = "\r\n./";
+ for (int ti = 0; ti < sizeof terminator; ti++)
+ {
+ char t = terminator[ti];
+ if (i == t)
+ continue;
+ mcel_t d = mcel_scant (ijk, t);
+ ASSERT (c.ch == d.ch && c.err == d.err && c.len == d.len);
+ if (!t)
+ {
+ mcel_t z = mcel_scanz (ijk);
+ ASSERT (d.ch == z.ch && d.err == z.err && d.len == z.len);
+ }
+ }
+ }
+}