tests/ui: A New Order [10/N]

[Kivooeo]

Note

Intermediate commits are intended to help review, but will be squashed prior to merge.

Some tests/ui/ housekeeping, to trim down number of tests directly under tests/ui/. Part of #133895.

r? @jieyouxu

[rustbot]

jieyouxu is not on the review rotation at the moment.
They may take a while to respond.

[jieyouxu]

Thanks, some feedback

[jieyouxu]

Problem: I think this is actually a regression test for #13360, IOW it has nothing to do with this comment, but was rather testing that boxed (?) ZSTs don't get freed (?). This test also doesn't really have to do with allocator/. Maybe check if there's a similar test under tests/ui/box/, otherwise I'd move this test under tests/ui/box/ and repurpose this as a smoke test for checking that we can dereference a boxed ZST.

[Kivooeo]

something like?

//! Regression test for github.com/rust-lang/rust/issues/13360
//! dereferencing boxed zero-sized types should not cause improper deallocation

[jieyouxu]

Question: I'm slightly confused, where did this file come from?

[Kivooeo]

this is from tests/ui/auxiliary

[jieyouxu]

Question: do we not have a tests/ui/resolve/ test that checks undefined macros are rejected? 🤔

[Kivooeo]

suprisingly but no, we dont have anything like this in resolve

maximum that ive found is

//@ edition:2018

foo!(); //~ ERROR cannot find macro `foo` in this scope

pub(in ::bar) struct Baz {} //~ ERROR cannot determine resolution for the visibility

fn main() {}

[jieyouxu]

Discussion: this might be useful as a control-flow smoke test, but it would need to //@ check-run-results and uncomment out the printlns to be of any actual value.

[Kivooeo]

we can keep this if you think so, but in my opinion this is very simple test, and we already have more complex recursive tests