disallow typedesc in arrays & move existing checks to types.typeAllowedAux

[nc-x]

Closes #9932

[Araq]

But this is arbitrary, instead it should call types.typeAllowed or types.typeAllowed should be patched to disallow it.

[timotheecour]

can it still happen now?

[nc-x]

This was existing code, so i don't know anything about this.
While reviewing, use the settings icon to Hide Whitespace Changes in order to see which code this PR changes.

[nc-x]

All tests pass. Ready for review. @Araq

Edit: Why does [skip ci] not work?

[timotheecour]

Edit: Why does [skip ci] not work?

you can upvote the issue I filed: microsoft/azure-pipelines-agent#2944
the workaround is to implement something like #13556 allow [nimDocOnly] in commit msg althouhg there are other ways to implement it

[Araq]

Do not use [skip ci], it's better to wait for the CIs, they are getting faster over time.

[nc-x]

AFAICT, the currently used CI services azure, github actions as well as builds.sr.ht do not support [ci skip], so we cannot use it anyways.

[timotheecour]

Do not use [skip ci], it's better to wait for the CIs, they are getting faster over time.

it's still useful for in-progress work, but yes when it's getting finalized CI is almost always needed.
Another typical example (while still in development)is: your CI is almost finished completed, but a push (say to fix a typo) would restart all jobs. sad.

[Araq]

Superb work, many thanks!