How to debug Rust in Helix?

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How to debug Rust in Helix?

2023-08-10

Helix supports debugging Rust by default using lldb-vscode. However, there is an issue where string variables are displayed as memory addresses instead of their actual values:

lldb-vscode - string variables memory addresses

Noticing that CodeLLDB natively supports visualization of most common Rust data types, I would like to give it a try.

Here’s the step-by-step process:

Download the CodeLLDB extension:

1$ cd ~/Downloads/
2$ wget https://github.com/vadimcn/codelldb/releases/download/v1.9.2/codelldb-aarch64-darwin.vsix

Setup the extension:

1$ mkdir -p ~/.local
2$ set fish_user_paths /Users/quantong/.local/extension/adapter $fish_user_paths
3$ codelldb

If you encountered this error:

1$ codelldb
2Error: "\"dlopen(/Users/quantong/.local/extension/lldb/lib/liblldb.dylib, 0x0009): 
3tried: \\'/Users/quantong/.local/extension/lldb/lib/liblldb.dylib\\' (code signature in <71492E0A-B915-3776-BCB8-266C07A85228> 
4\\'/Users/quantong/.local/extension/lldb/lib/liblldb.dylib\\' not valid for use in process: library load disallowed by system policy)\""

Remove attributes using xattr:

1$ xattr -cr ~/.local/extension/

Retry launching:

1$ codelldb --port 13000

Switch to use codelldb by adding the following to ~/.config/helix/languages.toml:

 1[[language]]
 2name = "rust"
 3
 4[language.debugger]
 5command = "codelldb"
 6name = "codelldb"
 7port-arg = "--port {}"
 8transport = "tcp"
 9
10[[language.debugger.templates]]
11name = "binary"
12request = "launch"
13
14[[language.debugger.templates.completion]]
15completion = "filename"
16name = "binary"
17
18[language.debugger.templates.args]
19program = "{0}"
20runInTerminal = false

1$ hx --health rust
2Configured language server: rust-analyzer
3Binary for language server: /opt/homebrew/bin/rust-analyzer
4Configured debug adapter: codelldb
5Binary for debug adapter: /Users/quantong/.local/extension/adapter/codelldb
6Highlight queries: ✓
7Textobject queries: ✓
8Indent queries: ✓

Create a new cargo package:

1$ cargo new hello_cargo

Open src/main.rs and add the following code:

1fn main() {
2    let s = "world";
3    let x = 2;
4    let b = true;
5    println!("Hello, {} {} {}!", s, x, b);
6}

Build your code by running:

1$ cargo build

The executable will be places in the target/debug directory.

In the Helix editor, use the following steps for debugging:

Press <Space> and then g to go to Debug.
Press b to toggle breakpoint.
Press l to launch debug target.
Enther the binary path target/debug/hello_cargo and press Enter.

After a few seconds, you’ll see the actual value of string variables:

codelldb - string variables values

Tags: helix dap lldb-vscode codelldb

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