typeck: suggest (x.field)(...) to call struct fields even when x is a reference

[birkenfeld]

Fixes: #33784

I also removed the unnecessary span for the note.

Reviewers: is this the right way to get at the deref'd type(s)? I tried expr_ty_adjusted, but it claimed "no type for node expr self"...

[rust-highfive]

r? @nikomatsakis

(rust_highfive has picked a reviewer for you, use r? to override)

[jonas-schievink]

Maybe using a full autoderef loop is a better idea, since that will work in more scenarios (it looks through explicit Deref impls, while builtin_deref doesn't)

[birkenfeld]

Can you point me to the right API to use for that?

[jonas-schievink]

That'd be FnCtxt::autoderef. You can see the usage in FnCtxt::is_fn_ty.

[birkenfeld]

Thanks! That was easier than I thought :)

[nikomatsakis]

Looks good to me, but note tidy failures:

https://travis-ci.org/rust-lang/rust/builds/132089654#L1231

[birkenfeld]

Damn, I have to get into the habit of running that locally. Fixed!

[nikomatsakis]

Note the failure here:

https://travis-ci.org/rust-lang/rust/builds/132746890#L5411

It seems like the easiest fix would be to add another instance of E055, but a better choice might be to suppress this lookup if we had an autoderef overflow already.

[nikomatsakis]

@birkenfeld given the tidy travis failure, I'm going to close this PR just to help manage the queue, but feel free to re-open when it's fixed.