Fix #5188: See through annotations and typevars when computing argume…

[odersky]

See through annotations (and typevars) when computing argument types.

[dottybot]

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[nicolasstucki]

The commit message has a typo, #5198 is not an issue.

[nicolasstucki]

I guess it was supposed to be #5188. Is that correct?

[nicolasstucki]

Change the commit message and add tests

[odersky]

Yes, #5188. I changed the commit message.

Changes where done

[odersky]

Now I get in -Ycheck:all:

Exception in thread "main" class dotty.tools.dotc.reporting.diagnostic.messages$Error at i5188.scala:3: right-hand side of inline value args must be a known value

The problem is that the varargs 1, 2, 3 are known values, but their translation SeqLiteral(1, 2, 3) is not. @nicolasstucki can you see what we should do about it? We could just disable the checkInlineConformant check in Retypers, but I am not sure that's the right thing to do here.

[nicolasstucki]

I will have a look.

[nicolasstucki]

The fix in TypeApplications.scala looks good to me. @liufengyun Could you review my additional commits. Thanks.

[liufengyun]

LGTM