Support for `envFile` in `rust-analyzer.runnables.extraEnv`

[hofbi]

https://rust-analyzer.github.io/book/editor_features.html#setting-runnable-environment-variables allows a user to specify extra environment variables. However, this only works for static environment variables. If some environment variables are user or host specific this approach won't work.

Similar to docker compose which supports both environment variables and env files, it would be great if rust analyzer could also support env files and load all variables defined inside this file(s).

[ChayimFriedman2]

The setting can be handled by the editor which can have it from whatever source, I don't believe it's the job of rust-analyzer.

[hofbi]

Looking into vscode, I found https://code.visualstudio.com/remote/advancedcontainers/environment-variables#_option-2-use-an-env-file but this seems to be for devcontainer only.

FYI, we are already using direnv to load these env files and have them available. Running env in any terminal shows that these variables are available. However, rust analyzer does not seem to recognize them. After hardcoding these variables in https://rust-analyzer.github.io/book/editor_features.html#setting-runnable-environment-variables, rust analyzer worked as expected. But as mentioned, these variables are dynamic so we can't hardcode them.

[ChayimFriedman2]

You can put them in .vscode/settings.json, and not commit it - making it per-user.

[hofbi]

We already have this file in version control for common settings. I already though about generating this file or a .vscode/settings.json.local but this would require microsoft/vscode#40233 which is open for almost 9 year now 😢

[ChayimFriedman2]

You can have a script to generate the settings (this is what https://github.com/rust-lang/rust does). I still believe this feature has no place in r-a.

[ShoyuVanilla]

FYI, we are already using direnv to load these env files and have them available. Running env in any terminal shows that these variables are available. However, rust analyzer does not seem to recognize them.

This is because vs-code and its rust-analyzer plugin doesn't inherit them from your terminal, unless you execute them within it with the command such as code .