No auto-completion inside fn (& attribute proc-macro)

[cynecx]

use tracing::instrument;

#[instrument]
fn testy() {
    let x = Vec::new();
    x.<|> // no auto completions here
}

[dependencies]
tracing = { version = "0.1.29", features = ["attributes"] }

rust-analyzer: 1e9ecb9 (master)

rust-analyzer should be able to trigger auto-completions at that position even with an attribute proc-macro at fn level (hover information works though).

[Veykril]

This is due to tracing::instrument using syn to parse the item which replaces the entire item with a compile_error invocation on parsing failure(which happens in this case because x. is not a valid expressions), https:/tokio-rs/tracing/blob/2f6fcb0fabff541d14b0fe3a5211b8f472fec4cb/tracing-attributes/src/lib.rs#L265-L266
See #10468

[cynecx]

See #10468

I see, that's unfortunate. Thought/Idea: Perhaps we could "catch" a compile_error invocation and just don't expand the attribute proc-macro at all as a recovery mechanism?

[Veykril]

We need to expand it to see the compile_error though, so I don't think that is easily doable but maybe someone can prove me wrong.

For the meantime I opened tokio-rs/tracing#1633

[Veykril]

Note you can get aroun this for the time being by disabling attribute expansion for your project again(we enabled it by default last week).

[lnicola]

@cynecx's tracing fix in tokio-rs/tracing#1634 just got merged.

[cynecx]

Thanks for all your input :)