+
+BOOST_AUTO_TEST_CASE (careful_string_filter_test)
+{
+ BOOST_CHECK_EQUAL ("hello_world", careful_string_filter("hello_world"));
+ BOOST_CHECK_EQUAL ("hello_world", careful_string_filter("héllo_world"));
+ BOOST_CHECK_EQUAL ("hello_world", careful_string_filter("héllo_wörld"));
+ BOOST_CHECK_EQUAL ("hello_world", careful_string_filter("héllo_wörld"));
+ BOOST_CHECK_EQUAL ("hello_world_a", careful_string_filter("héllo_wörld_à"));
+}