How to config RUSTUP_TOOLCHAIN environment variable using config?

[yanshay]

In https://rust-analyzer.github.io/manual.html#toolchain it's explained that to override rust-analyzer toolchain, in vscode need to configure using:
{ "rust-analyzer.server.extraEnv": { "RUSTUP_TOOLCHAIN": "stable" } }".

I'm using LazyVim with rustaceanvim so tried the following, but it doesn't have any effect:

return {
  "mrcjkb/rustaceanvim",
  ft = { "rust" },
  opts = {
    server = {
      default_settings = {
        -- rust-analyzer language server configuration
        ["rust-analyzer"] = {
          server = {
            extraEnv = { ["RUSTUP_TOOLCHAIN"] = "stable" // <--------- added this
            },
          }
        },
      },
    },
  },
}

If I set the environment variable globally in the system it does work, but not through this configuration.

How can I make it work using a configuration like the above?

[mrcjkb]

Hey 👋

rustaceanvim doesn't have a setup function, so you can't use lazy.nvim's opts table to configure it.

In LazyVim, you should be able to use opts to configure rustaceanvim if you have the rust extras enabled.

[yanshay]

I have the rust extras enabled, and then in order to configure the opts in lazyvim I add a file that includes the above config with the opts inside. Isn't that the right way to do it? (I'm doing it with many other plugins)

[mrcjkb]

I don't use LazyVim and don't have the capacity to provide support for Neovim distributions.
You're probably better off asking in the LazyVim discussions.