Conditional features limit with rust-analyzer?

[raycoe]

Hi,

Is there any limit in the number of features supported by rust-analyzer?
We have a project with about 25 features enabling us to (de)activate functionalities depending on the context, however we are a bit stuck using VSCode/rust-analyzer on Linux (Debian 13/Gnome) and MacOS Sequoia.

Thanks in advance
Ray

rust-analyzer version: 0.3.2660

rustc version: 1.90.0

editor or extension: VSCode 1.105.1

cargo.toml features def:

...
[features]
default = [ "all_features" ]
...

utils/mod.rs conditional cfg:

#[cfg(any(feature = "all_features", feature = "encoding"))]
pub mod iencoding;

Error raised by rust-analyzer:

utils/src/datasources/xml_reader.rs:237:54
    |
237 | ...                   Ok(s) => swappables::iencoding::HtmlEntity::get_decoded_str(&s.to_string()),
    |                                            ^^^^^^^^^ could not find `iencoding` in `swappables`
    |
note: found an item that was configured out
   --> utils/src/swappables/mod.rs:63:9
    |
 62 | #[cfg(any(feature = "all_features", feature = "encoding"))]
    |          ------------------------------------------------ the item is gated here
 63 | pub mod iencoding;

Wheras running cargo check/test doesn't raise any issue:

cargo test flib_utils_xml_reader_10
   Compiling utils v2.0.0 
    Finished `test` profile [unoptimized + debuginfo] target(s) in 1.00s
     Running unittests src/lib.rs (target/debug/deps/utils-ec548358a71e13e2)

running 1 test
test datasources::unit_tests::unit_test::flib_utils_xml_reader_10 ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 75 filtered out; finished in 0.00s

[ShoyuVanilla]

Error raised by rust-analyzer:

Where does it appear? Output panel on vs-code?

[raycoe]

Currently working at customer's site, which is a bank, I unfortunately won't be authorized to provide you with the project directory structure nor files. I'm even not able to post any zip or other files via attachment etc. as security systems will definitely block my requests - I can only copy/paste.

What is weird is that when issuing a cargo check command, there is no error raised. It's true that the error looks to be limited to the flycheck, however red indicators in VSCode are disturbing since I finally don't know if it is a real error or not until I compile.

When you mention your crate is affected by cargo's workspace feature unification, do you mean the root cause would be circular references?
If yes, I might be wrong but I would be amazed since the project is a single global lib source to which programs link using conditional features (via path = ... and features = ...). Everything was fine until we added some features end of last week; we went from 5 features to more than 20.

Would it be useful that I paste the toml content?

[ChayimFriedman2]

Can you try cargo check -p <package_you're_saving>?

[ShoyuVanilla]

I think given the restrictions the best way to find out the cause would be diagnosing with modified rust-analyzer by your own.

I'd suggest inserting tracing::error!(?cmd); below the following line

rust-analyzer/crates/rust-analyzer/src/flycheck.rs

Line 676 in 00ace81

cmd.args(&options.extra_args);

then build the rust-analyzer from your machine.
Then set rust-analyzer.server.path to your custom built rust analyzer and select rust-analyzer Language Server from your output panel.
It will show cmd=... things then you can try those commands manually to find out which one emits the error

[raycoe]

I made the requested modification, compiled the rust-analyzer and changed the rust-analyzer.server.path to point to the compiled binary.

Unable to activate rust-analyzer:

[Error - 5:57:48 PM] Rust Analyzer Language Server client: couldn't create connection to server.
Launching server using command /home/dev/Documents/_Tests_Validations/rust-analyzer-master/target/debug/ failed. Error: spawn /home/dev/Documents/_Tests_Validations/rust-analyzer-master/target/debug/ EACCES

[ShoyuVanilla]

You have to set it to the path to the rust-analyzer binary rather than its parent dir. And I'd recommend building as a release profile since the debug profile is slow

[ChayimFriedman2]

Does running cargo check --workspace also work?

[raycoe]

Yes, without problem

cargo check --workspace
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.48s

[ChayimFriedman2]

What are your rust-analyzer settings?

[raycoe]

Sorry if it is a silly question: do you want the 199 settings relating to rust-analyzer? Can I export them?

[ChayimFriedman2]

I want the settings you changed.