string-buffer-reversed: Add tests.

* tests/test-string-buffer-reversed.c: New file, based on
tests/test-string-buffer.c.
* modules/string-buffer-reversed-tests: New file.

ChangeLog

@@ -1,5 +1,10 @@
 2025-02-05  Bruno Haible  <bruno@clisp.org>
 
+	string-buffer-reversed: Add tests.
+	* tests/test-string-buffer-reversed.c: New file, based on
+	tests/test-string-buffer.c.
+	* modules/string-buffer-reversed-tests: New file.
+
 	string-buffer-reversed: New module.
 	* lib/string-buffer-reversed.h: New file, based on lib/string-buffer.h.
 	* lib/string-buffer-reversed.c: New file, based on lib/string-buffer.c.

modules/string-buffer-reversed-tests

@@ -0,0 +1,11 @@
+Files:
+tests/test-string-buffer-reversed.c
+tests/macros.h
+
+Depends-on:
+
+configure.ac:
+
+Makefile.am:
+TESTS += test-string-buffer-reversed
+check_PROGRAMS += test-string-buffer-reversed

tests/test-string-buffer-reversed.c

@@ -0,0 +1,182 @@
+/* Test of buffer that accumulates a string by piecewise concatenation.
+   Copyright (C) 2021-2025 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 2, 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/>.  */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2021.  */
+
+#include <config.h>
+
+#include "string-buffer-reversed.h"
+
+#include <errno.h>
+#include <string.h>
+#include <wchar.h>
+
+#include "macros.h"
+
+static int
+my_prependf (struct string_buffer_reversed *buffer, const char *formatstring,
+             ...)
+{
+  va_list args;
+
+  va_start (args, formatstring);
+  int ret = sbr_prependvf (buffer, formatstring, args);
+  va_end (args);
+
+  return ret;
+}
+
+char invalid_format_string_1[] = "%&";
+char invalid_format_string_2[] = "%^";
+
+int
+main ()
+{
+  /* Test accumulation.  */
+  {
+    struct string_buffer_reversed buffer;
+
+    sbr_init (&buffer);
+    sbr_prepend1 (&buffer, '\377');
+    sbr_prepend1 (&buffer, 'x');
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s != NULL && strcmp (s, "x\377") == 0);
+    free (s);
+  }
+  {
+    struct string_buffer_reversed buffer;
+
+    sbr_init (&buffer);
+    sbr_prepend1 (&buffer, '\377');
+    sbr_prepend1 (&buffer, 'x');
+    {
+      string_desc_t sd = sbr_contents (&buffer);
+      ASSERT (sd_length (sd) == 2);
+      ASSERT (sd_char_at (sd, 0) == 'x');
+      ASSERT (sd_char_at (sd, 1) == '\377');
+    }
+    sbr_prepend1 (&buffer, '\0');
+    sbr_prepend1 (&buffer, 'z');
+    {
+      string_desc_t sd = sbr_contents (&buffer);
+      ASSERT (sd_length (sd) == 4);
+      ASSERT (sd_char_at (sd, 0) == 'z');
+      ASSERT (sd_char_at (sd, 1) == '\0');
+      ASSERT (sd_char_at (sd, 2) == 'x');
+      ASSERT (sd_char_at (sd, 3) == '\377');
+    }
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s != NULL && memcmp (s, "z\0x\377\0", 5) == 0);
+    free (s);
+  }
+
+  /* Test simple string concatenation.  */
+  {
+    struct string_buffer_reversed buffer;
+
+    sbr_init (&buffer);
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s != NULL && strcmp (s, "") == 0);
+    free (s);
+  }
+
+  {
+    struct string_buffer_reversed buffer;
+
+    sbr_init (&buffer);
+    sbr_prepend_c (&buffer, "efg");
+    sbr_prepend_c (&buffer, "");
+    sbr_prepend_c (&buffer, "abcd");
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s != NULL && strcmp (s, "abcdefg") == 0);
+    free (s);
+  }
+
+  {
+    struct string_buffer_reversed buffer;
+
+    sbr_init (&buffer);
+    sbr_prepend_c (&buffer, "hij");
+    sbr_prepend_desc (&buffer, sd_new_addr (5, "de\0fg"));
+    sbr_prepend_c (&buffer, "abc");
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s != NULL && memcmp (s, "abcde\0fghij", 12) == 0);
+    free (s);
+  }
+
+  /* Test printf-like formatting.  */
+  {
+    struct string_buffer_reversed buffer;
+
+    sbr_init (&buffer);
+    sbr_prepend_c (&buffer, ">");
+    sbr_prependf (&buffer, "%x", 3735928559U);
+    sbr_prepend_c (&buffer, "<");
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s != NULL && strcmp (s, "<deadbeef>") == 0);
+    free (s);
+  }
+
+  /* Test vprintf-like formatting.  */
+  {
+    struct string_buffer_reversed buffer;
+
+    sbr_init (&buffer);
+    sbr_prepend_c (&buffer, ">");
+    my_prependf (&buffer, "%x", 3735928559U);
+    sbr_prepend_c (&buffer, "<");
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s != NULL && strcmp (s, "<deadbeef>") == 0);
+    free (s);
+  }
+
+  /* Test printf-like formatting failure.
+     On all systems except AIX, trying to convert the wide-character 0x76543210
+     to a multibyte string (in the "C" locale) fails.
+     On all systems, invalid format directives make the vsnzprintf() call
+     fail.  */
+  {
+    struct string_buffer_reversed buffer;
+    int ret;
+
+    sbr_init (&buffer);
+    sbr_prepend_c (&buffer, ">");
+
+    ret = sbr_prependf (&buffer, "%lc", (wint_t) 0x76543210);
+    #if !(defined _AIX || (defined _WIN32 && !defined __CYGWIN__))
+    ASSERT (ret < 0);
+    ASSERT (errno == EILSEQ);
+    #endif
+
+    sbr_prepend_c (&buffer, "|");
+
+    ret = sbr_prependf (&buffer, invalid_format_string_1, 1);
+    ASSERT (ret < 0);
+    ASSERT (errno == EINVAL);
+
+    sbr_prepend_c (&buffer, "|");
+
+    ret = sbr_prependf (&buffer, invalid_format_string_2, 2);
+    ASSERT (ret < 0);
+    ASSERT (errno == EINVAL);
+
+    sbr_prepend_c (&buffer, "<");
+    char *s = sbr_dupfree_c (&buffer);
+    ASSERT (s == NULL);
+  }
+
+  return test_exit_status;
+}