storage: add a test for unique key doesn't match mixed case

It is caused by a groonga bug. It was fixed in
groonga/groonga@8d8af5c

[groonga-dev,01187]

Reported by Kouhei Tanabe. Thanks!!!

test/sql/suite/mroonga/storage/index/unique/r/varchar.result

@@ -0,0 +1,15 @@
+DROP TABLE IF EXISTS users;
+CREATE TABLE users (
+name varchar(100) NOT NULL,
+UNIQUE KEY name (name)
+) DEFAULT CHARSET=utf8;
+INSERT INTO users VALUES ("Alice");
+INSERT INTO users VALUES ("Bob");
+SELECT * FROM users;
+name
+ALICE
+BOB
+SELECT * FROM users WHERE name = "aLiCe";
+name
+ALICE
+DROP TABLE users;

test/sql/suite/mroonga/storage/index/unique/t/varchar.test

@@ -0,0 +1,36 @@
+# Copyright(C) 2013 Kouhei Sutou  <kou@clear-code.com>
+#
+# This library 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 2.1 of the License, or (at your option) any later version.
+#
+# This library 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 library; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+--source include/have_mroonga.inc
+
+--disable_warnings
+DROP TABLE IF EXISTS users;
+--enable_warnings
+
+CREATE TABLE users (
+  name varchar(100) NOT NULL,
+  UNIQUE KEY name (name)
+) DEFAULT CHARSET=utf8;
+
+INSERT INTO users VALUES ("Alice");
+INSERT INTO users VALUES ("Bob");
+SELECT * FROM users;
+
+SELECT * FROM users WHERE name = "aLiCe";
+
+DROP TABLE users;
+
+--source include/have_mroonga_deinit.inc