Destructuring query tuple types shown as {unknown} in Rust Analyzer

[yngwi]

Hi,

I'm starting to learn Rust and Bevy using Neovim with Rust Analyzer as language server. So far it works just fine. I have one question, though:

When I have the following function:

fn greet_people(query: Query<(&Name, &Position), (With<Person>, With<Position>)>) {
    for (name, pos) in query.iter() {
        println!("hello {} at {}/{}!", name.0, pos.x, pos.y);
    }
}

Rust analyzer shows the types of name and pos as {unknown}. Using this kind of destructuring on other things like let (x, y) = ("x", "y"); shows the correct types for x and y. Is there something I can do to also get the correct type hints for the query iterator?

Thanks,
Daniel

[bjorn3]

Either chalk is not able to resolve all types or you don't have proc macros enabled.

[yngwi]

Hi. Thank you for your reply. I think I have it enabled, this is my language server configuration:

settings = {
	["rust-analyzer"] = {
		checkOnSave = {
			features = "all",
			command = "clippy",
		},
		procMacro = {
			enable = true,
		},
	},
},

I am seeing the following error message in the LSP Logs:

[ERROR][2022-07-03 17:22:55] .../vim/lsp/rpc.lua:430 "rpc" "rust-analyzer" "stderr" "thread 'MacroExpander' panicked at 'assertion failed: (left != right)\n left: 0,\n right: 0', crates\\proc-macro-srv\\src\\abis\\abi_1_63\\proc_macro\\bridge\\handle.rs:22"

Unfortunately I have no Idea what that means or if it is indeed related to the problem.

[yngwi]

rust-lang/rust-analyzer#12600 This issue seems to be about this kind of crash, maybe it is indeed related...

[bjorn3]

That is probably the cause. You can switch to stable or beta rustc until we add support for the new proc macro abi the latest nightly versions use.

[yngwi]

ok thank you