Terminal API: debounce onData()?

[bpasero]

Refs: #48434

It looks like every single character I type produces a onData event in the terminal. Should this maybe be debounced? What is the scenario for having this API that it needs to fire on each keystroke?

[Tyriar]

I was actually introducing this at a lower level than this, but it would probably not be enabled for standard vscode terminals microsoft/node-pty#189, it may actually slow things down unless things are going over the wire.

Some debouncing would be a good idea between the renderer and extension host.

[JacksonKearl]

Is this user-facing? How can I verify?

[Tyriar]

@eamodio can you put some steps in please?

[eamodio]

To test this you need to create an extension:

1. Run npx -p yo -p generator-code -c 'yo code --extensionType=command-ts' to scaffold an extension
2. Add "enableProposedApi": true to the package.json
3. Change "activationEvents" in the package.json to "activationEvents": ["*"]
4. Replace the activate function in extension.ts with the following

export function activate(context: vscode.ExtensionContext) {
    context.subscriptions.push(
        (vscode.window as any).onDidWriteTerminalData(
            (e: { readonly terminal: vscode.Terminal; readonly data: string }) => {
                console.log(`${e.terminal.name}\n${e.data}`);
            }
        )
    );
}

1. Run the extension and switch to the Debug Console
2. In the newly launched vscode extension host window, open a terminal and run an ls command or a command that will output a bunch of data
3. Back in the original vscode window, in the Debug Console ensure you see the output from the terminal with multiple lines for each event (prior to these changes it would have only be 1 line per event at most)