[Issue 18235] Group logically similar tests into the same module in the D2 testsuite

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=18235

--- Comment #1 from Seb <greensunny12 at gmail.com> ---
Not saying anything about the logical grouping, but this is a bit exaggerated
imho:

> Each new file added to the testsuite may as well be adding 5 seconds onto the overall runtime.  

_All_ 1283 fail_compilation tests compile in ~11s on my machine.
The 774 compilable tests are slightly slower with ~25s ... and you don't want
to know how long runnable takes :/
(of course the numbers are taken with full parallelism on an i7 4th Gen)

Anyhow, if someone wants to make the testsuite faster, the runnable tests are
the real bad boys and should be focussed on first.

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