std.array string.split("") bug

[Borislav Kosharov]

Something strange happens when I do this:

unittest {
     import std.array, std.string;
     string s = "test";
     //assert(s.toUpper.split("").join("-") == "T-E-S-T");
     //"Memory allocation failed"
     //[Finished in 26.5s]
     //CPU: 1% -> 50% | 2.7GHz dual core
     //RAM: 1.6GB -> 2.6GB | 1GB diff
     assert(s.split("") == ["t","e","s","t"]);
     //ditto
}

I just want to achieve what the commented assert's result should 
be. Is there a better way to do that? And if it is really a bug 
where should I report it?