Debug functionalilty broken in VS code on MacOS

[git-luke]

rust-analyzer version: 0.3.1885-standalone (b6d1887 2024-03-17)
Issue also occurs on 0.3.1877-standalone (574e23e 2024-03-09)
Does not occur on previous versions.

rustc version: rustc 1.73.0 (cc66ad468 2023-10-03)

relevant settings: (eg. client settings, or environment variables like CARGO, RUSTC, RUSTUP_HOME or CARGO_HOME)

• MacOS 14.3.1 with Apple M1 Pro
• VS Code Version: 1.87.1 (Universal)
• CodeLLDB v1.10.0
• No configurations in launch.json:

{
    "version": "0.2.0",
    "configurations": []
}

Running any #[test] > Debug results in popup:
"Unable to start debugging. Launch options string provided by the project system is invalid. Unable to determine path to debugger. Please specify the "MIDebuggerPath" option."

• No change in any setting other than updating the rust-analyzer extension to one of the two versions above triggers this issue.
• No problems on rust-analyzer version: 0.3.1868-standalone (037924c 2024-03-03) or lower.

repository link (if public, optional): -

code snippet to reproduce:

#[test]
// any test

Thank you for investigating!

[trueb2]

This was confusing since there was no setting change and the error message is misleading. Downgrading the VS Code extension allowed debugging again.

• MacOS 14.4
• VS Code 1.87.1 (Universal)
• CodeLLDB v1.10.0.

I can confirm as well that 0.3.1868 and earlier are working. All debugging is broken on and after v0.3.1877

[yayanyang]

The same thing happened to me.

[pmq20]

The same thing happened to me.

[roife]

This issue cannot be reproduced on my machine (M3 Max, macOS 14.3.1). If the problem was introduced by v0.3.1877, could it be related to commit a01e4f8 (#16719)?

[akrylysov]

Seeing same issue and I can confirm that downgrading to v0.3.1868 solves it.

[NateAGeek]

Agree, somehow downgrading to v0.3.1868 resolved it.

[roife]

Oh, I'm able to reproduce this issue now. This problem only occurs when users have the C++ plugin installed. (This explains why I couldn't reproduce it before.)

@rustbot claim

[lnicola]

This might be #16719. The C/C++ extension seems to work for me on Linux, but indeed, I get an empty launch.json.

[lnicola]

Actually no: I reverted #16719 and get the same behavior:

• F5: doesn't work: "program 'enter program name, ...'" does not exist
• Debug lens on main: works, doesn't create launch.json
• rust-analyzer: Debug command: takes a couple of tries ("looking for runnables"), then works, still doesn't create launch.json

[roife]

In #16719, the order of the debugger changed, prioritizing "ms-vscode.cpptools", which resulted in the error. However, debugging with codelldb still works fine even without generating a launch.json file.

[lnicola]

Oh 🤦. I didn't expect anyone to have multiple debugging extensions, but it makes sense with the C++ one.