Unittest hangs on completion

[David Zhang via Digitalmars-d-learn]

On Saturday, 31 December 2016 at 02:03:07 UTC, rikki cattermole 
wrote:
> As it should, current is never reassigned.
> You only need one var, next. Of course I didn't read the entire 
> thread chain so, I'm probably missing something.
>
> import std.experimental.allocator;
>
> void main() {
>         struct S { S* next; }
>         S* _foo;
>         foreach (e; 0 .. 10)
>                 _foo = theAllocator.make!S(_foo);
>         S* next;
>
>         next = _foo;
>         while(next !is null) {
>                 auto nextT = next.next;
>                 theAllocator.dispose(next);
>                 next = nextT;
>         }
> }

Thanks for your response. So next is never null, and thus there 
is an infinite loop, correct? If so, why does dub indicate that 
all tests are complete?