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+++ b/tests/unistr/test-u16-strmblen.c
@@ -0,0 +1,78 @@
+/* Test of u16_strmblen() function.
+   Copyright (C) 2010 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 <http://www.gnu.org/licenses/>.  */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2010.  */
+
+#include <config.h>
+
+#include "unistr.h"
+
+#include "macros.h"
+
+int
+main ()
+{
+  int ret;
+
+  /* Test NUL unit input.  */
+  {
+    static const uint16_t input[] = { 0 };
+    ret = u16_strmblen (input);
+    ASSERT (ret == 0);
+  }
+
+  /* Test ISO 646 unit input.  */
+  {
+    ucs4_t c;
+    uint16_t buf[2];
+
+    for (c = 1; c < 0x80; c++)
+      {
+        buf[0] = c;
+        buf[1] = 0;
+        ret = u16_strmblen (buf);
+        ASSERT (ret == 1);
+      }
+  }
+
+  /* Test BMP unit input.  */
+  {
+    static const uint16_t input[] = { 0x20AC, 0 };
+    ret = u16_strmblen (input);
+    ASSERT (ret == 1);
+  }
+
+  /* Test 2-units character input.  */
+  {
+    static const uint16_t input[] = { 0xD835, 0xDD1F, 0 };
+    ret = u16_strmblen (input);
+    ASSERT (ret == 2);
+  }
+
+  /* Test incomplete/invalid 1-unit input.  */
+  {
+    static const uint16_t input[] = { 0xD835, 0 };
+    ret = u16_strmblen (input);
+    ASSERT (ret == -1);
+  }
+  {
+    static const uint16_t input[] = { 0xDD1F, 0 };
+    ret = u16_strmblen (input);
+    ASSERT (ret == -1);
+  }
+
+  return 0;
+}