Can a command be send to VSCode, directly from the integrated terminal (integrated terminal -> VSCode API)? - visual-studio-code

Question

Hi I would like to know whether one could call a VSCode command from the integrated terminal. So basically is the terminal aware of VSCode and can they communicate (at least from terminal => VSCode)
My Usecase: I would like to have H and L, to move to editor tab left / right of the terminal (I am using the terminal in an editor tab). Additionally, I would like that to happen when I am in vim normal mode in my zsh.
So I would like, when I am in normal mode and press H that the terminal sends an editor.tabNext (or whatever the command is) to VSCode.

Answer 1

I think I found a workaround at least. There is an extension called Remote Control (https://marketplace.visualstudio.com/items?itemName=eliostruyf.vscode-remote-control&ssr=false#review-details), with which I can send arbitrary commands to VSCode, so this seems to work. Proabably natively this is not possible, but maybe someone knows something.
EDIT1:
Here is my setup now:
if [ ! -z $VSCODE ]; then
_sendcmd() { echo "{ \"command\": \"workbench.action.$1\" }" | websocat ws://localhost:4242 }
# define commands and register them in zsh
editor_left() { _sendcmd previousEditor }; zle -N editor_left;
editor_right() { _sendcmd nextEditor }; zle -N editor_right;
bindkey -a H editor_left
bindkey -a L editor_right
fi
where $VSCODE is defined in VSCode through terminal.integrated.env = { "VSCODE": "1" }. May this make you as happy as it makes me happy.

Answer 2

Yes you can do this but it will require writing a simple extension and there is one flaw with it.
If you write a VSCode extension there is an API that will set environment variables in new terminals.
export function activate(context: ExtensionContext) {
...
context.environmentVariableCollection.replace("REMOTE_CONTROLL_EXTENSION_IPC_PATH", ipcPath);
What you do is create a Unix socket (or named pipe on Windows) and pass it into that environment variable. Then in your shell you can just send data to that socket.
This is much better than the approach used by the Remote Control extension that Dimfred mentioned - it's more secure and doesn't rely on known fixed ports, which means you're going to run into issues e.g. if they don't get closed properly or you run multiple copies of VSCode.
The only downside I've found with this approach is that if restart VSCode, then the socket will be closed but VSCode will try to restore shell sessions. Those shell sessions will be left with an old REMOTE_CONTROLL_EXTENSION_IPC_PATH value which points at a non-existent socket.
I'm not sure of a way around that yet.
Edit: Actually all you need to do is ensure your Unix socket path is tied to a workspace. At least this is what the built in Git extension does. See createIPCServer(). It uses storagePath which is specific to a workspace. It also unlinks the socket at that path (if any) when it starts.
I initially thought that might cause issues if you open the same workspace twice in two windows, but VSCode won't let you do that.