fix issue 20324 - Calling __traits(getUnitTests) on a template causes compiler segfault

[ghost]

The idea is that you cannot get the tests of a partially specialized type. unittest blocks inside a partially specialized type may use or not the template parameters so allowing them would require a complex analysis.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20324	minor	Calling __traits(getUnitTests) on a template causes compiler segfault

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "stable + dmd#10533"

[Geod24]

It would be better to say what the type passed is.

[ghost]

I have doubts anyway. I used a tester based on the trait but my own code doesn't contain any inner unittest block so I need to verify one or two things. TLDR; don't merge fast... there's two or three weeks before next bug fix release anyway.

[Geod24]

Applied a label, feel free to ping to have it removed.

[ghost]

I've changed the approach and decided not to issue an error.

[ghost]

ping for the removal of the blocked "label", checks done.

[Geod24]

I've changed the approach and decided not to issue an error.

That might be a surprising behavior. Can you expand on why you went with this approach ? Adding the explanation in the commit message would be great too.

[ghost]

1. This makes writing a generic tester more friendly, with less static if.
2. On the principle of least astonishment, I'm less astonished by no error than by an error. It's pretty obvious that templates that are not instances are not usable. For example when I made the fix I didn't even tried to see where the AV happened, I directly opened traits.d because the place to fix the crash was obvious.

[RazvanN7]

Hmm, I wanted to close and reopen to restart the autotester, but it seems like the branch was deleted and I cannot reopen. It seems like the github account was deleted.