Rust analyzer not fully functional in esp-rs/esp-idf projects?

[weiying-chen]

I generated an esp-rs/esp-idf project using the official template.

Then I modified it like this:

fn main() {
    use esp_idf_svc::{
        hal::prelude::Peripherals,
        sys::link_patches,
    };

    esp_idf_svc::log::EspLogger::initialize_default();

    let peripherals = Peripherals::take()?;
}

There were no warnings or errors in my text editor (Helix), which uses rust-analyzer. Is there something in a esp-rs/esp-if project that makes rust-analyzer not catch there common issues? The Rust compiler did catch the errors, though:

warning: unused import: `sys::link_patches`

error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)

Note: if I go to a non-esp-rs/esp-if project, I do see these warnings and errors in my text editor.

Update: I think this line in Cargo.toml is deactivating those warnings and errors. But I still don't know why.

[dependencies]
esp-idf-svc = { version = "0.48", default-features = false }

[Vollbrecht]

rust-analyzer works perfectly fine. Though the problem itself is more often that RA doesn't pick up the correct cargo configs. So it's more a matter of telling RA directly the same configs, that are included inside the .cargo/config.toml file, like target, feature flags etc. How you can configure RA is dependent on the integration in your editor/ide. Check how you can configure it on your env and look here for the possible settings. You can try out the extaArgs + extraEnv and the target ones. Note that there are settings for .cargo and for .check as they are for different RA invocations you may need to set both configs.

[weiying-chen]

This is my Helix log when I open a Rust project that has esp-idf-svc as a dependency:

2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "2024-02-17T11:37:28.907967Z ERROR rust_analyzer::main_loop: FetchBuildDataError:\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "error[E0531]: cannot find unit struct, unit variant or constant `SIGABRT` in crate `libc`\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "   --> /home/weiying-chen/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/test/src/test_result.rs:102:24\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "    |\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "102 |             Some(libc::SIGABRT) => TestResult::TrFailed,\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "    |                        ^^^^^^^ not found in `libc`\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "error: aborting due to 1 previous error\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "For more information about this error, try `rustc --explain E0531`.\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "error: could not compile `test` (lib) due to 2 previous errors\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "\n"
2024-02-17T19:37:28.908 helix_lsp::transport [ERROR] rust-analyzer err <- "\n"
2024-02-17T19:37:28.914 helix_term::application [WARN] unhandled window/showMessage: ShowMessageParams { typ: Warning, message: "Failed to run build scripts of some packages." }
2024-02-17T19:37:29.579 helix_term::application [WARN] unhandled window/showMessage: ShowMessageParams { typ: Warning, message: "Failed to run build scripts of some packages." }

I think the issue is Helix, not esp-idf-svc.

Note: I did rustup update (which also updated Rust nightly), but I'm getting the same error.

Update: Many people are having exactly the same issue. There's an issue with rust-analyzer and esp-idf projects.

[weiying-chen]

Thanks to this comment, I found out rust-analyzer works perfectly in esp-idf projects if you use rustc 1.77.0-nightly (2a3e63551 2023-12-30). The issue is rustc 1.78.0-nightly (ee9c7c940 2024-02-14).

[juliankrieger]

@weiying-chen I can't really confirm this. I've been having Problems with RA showing errors on exported crates which require ESP components, for example eventloop:

My toolchains are as following:

I am on rustc.177.0-nighty, my project however is using the esp toolchain:

[weiying-chen]

@juliankrieger So your point is that RA also has issues with rustc.177.0-nighty when analyzing ESP projects?

[julienvincent]

I have been running into the same issue. I upgraded my nightly to 1.79-0-nightly and now rust-analyzer is broken in all my esp projects.

[Vollbrecht]

@weiying-chen your issue comes from the fact that rust-analyzer by default try's to build cargo test with the rust "libtest" framework. This can be mitigated by adding

[[bin]]
name = "{{project-name}}"
harness = false # do not use the built in cargo test harness -> resolve rust-analyzer errors

to your Cargo.toml.

rust-analyzer should work fine with that option. I am closing this, feel free to reopen it if that doesn't solve this particular problem or create a new issue. Thanks!

[faulesocke]

Even with that, rust analyzer seems to not work correctly in my library crate. Running cargo clippy --all-targets now complains:

error[E0601]: `main` function not found in crate `esp_os`
   --> src/lib.rs:247:2
    |
247 | }
    |  ^ consider adding a `main` function to `src/lib.rs`

I added this to my Cargo.toml:

[lib]
harness = false

But whats more annoying is that I'm currently trying to write an example, so I added

[[example]]
name = "basic"
harness = false

But I still don't see error messages reliably in my examples/basic.rs file (maybe due to the bogus main function error?)

Can this be resolved on the esp-rs side or has this to be fixed in rustc itself?