Can we get unitests to not run with program start ?

[Sönke Ludwig via Digitalmars-d]

Am 26.10.2016 um 15:25 schrieb Adam D. Ruppe:
> On Wednesday, 26 October 2016 at 08:15:44 UTC, Basile B. wrote:
>> What would be possible is a "-fdmain" switch (force dummy main).
>
> It should just be implied by -unittest!
>
> The only cast I'd be worried about is an explicit version(unittest)
> main() {}... then maybe the user wanted something special. And even
> then, meh, 99% of those cases are just fixing the broken default anyway.
>
> Otherwise, let's make the default sane.

How would a custom unit test runner such as "unit-threaded" or "tested" 
work in that case?