rust-analyzer: Regression: Proc macros not being expanded

It seems that proc macro support degraded heavily from the previous version of RA for me. In the last version, both web-sys autocomplete and proc macro inlay hints worked.

Now, it seems that RA is blind to any web-sys types (once again) and none of my proc macros are being expanded (proc macro not expanded rust-analyzerunresolved-proc-macro). My proc macro is fairly well behaved and, in the past, had significant IDE support for hovers/go-to/inlay hints.

For instance, my code

let g = rsx!(div {});

expands to

    let g = NodeFactory::annotate_lazy(move |__cx: NodeFactory| -> VNode {
        __cx.element(dioxus_elements::div, [], [], [], None)
    });

I would expect to see hints on div since I re-use the token literally, but the macro simply fails to expand.

Is there a different proc-macro server I can use that works?

rust-analyzer version: d9b2291f5 2021-11-29 stable

rustc version: rustc 1.56.1 (59eed8a2a 2021-11-01)

About this issue

Original URL
State: closed
Created 3 years ago
Reactions: 14
Comments: 28 (11 by maintainers)

Commits related to this issue

Merge #11002 11002: fix: Add support for v6 macro metadata format r=lnicola a=lnicola CC https://github.com/rust-analyzer/rust-analyzer/issues/10894#issuecomment-991993824 bors r+ Co-authored-by... — committed to rust-lang/rust-analyzer by bors[bot] 3 years ago

Most upvoted comments

Chiming in to say I had an issue with this when writing a fresh derive macro, and it went away when I reloaded rust-analyzer (rust-analyzer: Restart Server in VSCode).

My precise output from rust-analyzer was “Proc macro not expanded: no proc macro dynlib present”.

+26

isosphere on Oct 23, 2022

Digging a bit deeper it turns out that yes, I simply didn’t correctly enable proc-macros in the LSP config. For anyone else in my same situation, the answer was (setq-default lsp-rust-analyzer-proc-macro-enable t).

I agree that it’d be nice to have more informative errors. Something along the lines of proc-macro expansion disabled in configuration would help separate user configuration errors from legitimate rust-analyzer errors.

Palladinium on Feb 8, 2022

Let’s close this since the original issue is not reproducible, and the ticket risks becoming a dumping ground for proc macro expansion problems.

flodiebold on May 28, 2022

I also run into this problem on Doom Emacs, I use rust-analyzer ba3305480 2022-02-07 stable and rustc 1.56.1 (59eed8a2a 2021-11-01).

I’m sure my lsp-rust-analyzer-proc-macro-enable is set to t, in fact I have no problem expand locally declared macro, but failed to correctly expand foreign (imported) proc macro.

(btw, I also confirm the output of expanded code on vscode via “Rust Analyzer: Expand macro recursively” to perfectly matched that of my emacs, both have no issue with locally defined macro, but both failed with imported macro)

alxiong on Feb 12, 2022

I can confirm this is still an issue.

2022-02-04_12_23_745228021

rust-analyzer was installed with cargo install rust-analyzer --git https://github.com/rust-analyzer/rust-analyzer.git --locked Running in Spacemacs with the Rust layer.

$ rustc --version
rustc 1.60.0-nightly (27f5d830e 2022-02-02)
$ rust-analyzer --version
rust-analyzer 9597e55e9 2022-02-04 dev

I am positive this is the only version of rust-analyzer I have installed - Spacemacs does not install its own version.

Palladinium on Feb 4, 2022

@al2me6 can you try with the next RA nightly? This seems to work now for me.

@alexjg false alert 😃.

lnicola on Dec 13, 2021

for me, the issue turned out to be that I had a sub project in my repo that I decided to delete and remove…but the vscode/settings.json had this in it:

{ “rust-analyzer.linkedProjects”: [ “./Cargo.toml”, “./Deleted_Project/Cargo.toml” ] }

I deleted the “./Deleted_Project/Cargo.toml” line and the problem went away

i’td be awesome if rust-analyzer reported that I was asking for it to link to a project that no longer existed and stopped executing.

joelong01 on Jul 31, 2023

@al2me6 you need to try with the next nightly.

lnicola on Dec 13, 2021