Rust-analyzer ignores "--locked" modifier and keeps changing the lockfile

[Pzixel]

I have Cargo.toml file that doesn't match Cargo.lock file and following .vscode config file:

{
    "rust-analyzer.check.extraArgs": [
        "--locked"
    ],
    "rust-analyzer.cargo.buildScripts.overrideCommand": [
      "cargo",
      "check",
      "--quiet",
      "--workspace",
      "--message-format=json",
      "--all-targets",
      "--keep-going",
      "--locked"
    ],
    "rust-analyzer.cargo.extraArgs": [
      "--locked"
    ]
}

When starting rust-analyzer I expect it to type check the project but not change the lock file. Currently when starting rust-analyzer still changes the lock file even when given the config to not:

rust-analyzer version: rust-analyzer version: 0.3.2273-standalone (248bd51 2025-01-18)

rustc version: rustc 1.85.0-nightly (6d9f6ae36 2024-12-16)

editor or extension: VSCode

[Veykril]

rust-analyzer invokes cargo metadata on start (which you can't overwrite the behavior of), so that likely changes your lockfile. Either way even if you could it still wouldn't work as cargo metadata --locked will error when the lockfile needs to be changed meaning we can't analyze your project.

[Pzixel]

Do you think it's not worth it to add support to cargo metadata to allow this behavior and expose this as a config? Because currently it can lead to situation where you just open the project and it already pollutes the git state which disables some command (like git checkout).

Also thank you for such a quick answer, it's indeed the cargo metadata's issue

[Veykril]

I believe --locked asserting is deliberate (and likely couldn't be changed even if not anymore), but that is something the cargo folks would know. This issue is somewhat related to rust-lang/cargo#10096

[Pzixel]

Thank you, this is extremely helpful

[Veykril]

Fyi #20018 will fix this for you here