Why think unit tests should be in their own source code hierarchy instead of side-by-side

[Steven Schveighoffer]

On 3/22/18 6:59 AM, Atila Neves wrote:
> Blog post:
> 
> https://atilanevesoncode.wordpress.com/
> 
> Atila

It's simple. Unittests in imported modules should not be visible. They 
should be compiled as if -unittest was not passed.

Even Walter and Andrei are supportive: 
https://github.com/dlang/dmd/pull/6375#issuecomment-373487247

-Steve