1 files changed, 80 insertions, 0 deletions
diff --git a/tests/unigbrk/test-u8-grapheme-prev.c b/tests/unigbrk/test-u8-grapheme-prev.c
new file mode 100644
index 00000000..3f691800
--- /dev/null
+++ b/tests/unigbrk/test-u8-grapheme-prev.c
@@ -0,0 +1,80 @@
+/* Previous grapheme cluster test.
+   Copyright (C) 2010-2015 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Ben Pfaff <blp@cs.stanford.edu>, 2010. */
+
+#include <config.h>
+
+/* Specification. */
+#include <unigbrk.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "macros.h"
+
+static void
+test_u8_grapheme_prev (const char *input, size_t n, size_t len)
+{
+  const uint8_t *s = (const uint8_t *) input;
+  const uint8_t *end = s + n;
+  const uint8_t *prev = u8_grapheme_prev (end, s);
+  if (prev != end - len)
+    {
+      size_t i;
+
+      if (prev == NULL)
+        fputs ("u8_grapheme_prev returned NULL", stderr);
+      else
+        fprintf (stderr, "u8_grapheme_prev skipped %zu bytes", end - prev);
+      fprintf (stderr, ", expected %zu:\n", len);
+      for (i = 0; i < n; i++)
+        fprintf (stderr, " %02x", s[i]);
+      putc ('\n', stderr);
+      abort ();
+    }
+}
+
+int
+main (void)
+{
+  static const uint8_t s[] = "abc";
+
+  /* Empty string. */
+  ASSERT (u8_grapheme_prev (NULL, NULL) == NULL);
+  ASSERT (u8_grapheme_prev (s, s) == NULL);
+
+  /* Standalone 1-unit graphemes.  */
+  test_u8_grapheme_prev ("a", 1, 1);
+  test_u8_grapheme_prev ("ab", 2, 1);
+  test_u8_grapheme_prev ("abc", 3, 1);
+
+  /* Multi-unit, single code point graphemes. */
+#define HIRAGANA_A "\343\201\202" /* あ: Hiragana letter 'a'. */
+  test_u8_grapheme_prev (HIRAGANA_A, 3, 3);
+  test_u8_grapheme_prev (HIRAGANA_A"x", 4, 1);
+  test_u8_grapheme_prev (HIRAGANA_A HIRAGANA_A, 6, 3);
+
+  /* Combining accents. */
+#define GRAVE "\314\200"        /* Combining grave accent. */
+#define ACUTE "\314\201"        /* Combining acute accent. */
+  test_u8_grapheme_prev ("e"ACUTE, 3, 3);
+  test_u8_grapheme_prev ("e"ACUTE GRAVE, 5, 5);
+  test_u8_grapheme_prev ("e"ACUTE"x", 4, 1);
+  test_u8_grapheme_prev ("e"ACUTE "e"ACUTE, 6, 3);
+
+  return 0;
+}