Show pseudo-pending text for `ms`/`mr`/`md` commands

[AceofSpades5757]

Describe your feature request

Add contextual pop-ups, just like when the Match box pops up after pressing m for when Helix is waiting for the input to the next command, like Surround delete.

So, after a user presses m and then d to do a surround delete, it would be nice to have another box either show their available options, or at least give some instructions on what to do next. This could also help with more advanced subcontexts, such as if there was a regex surround delete.

[the-mikedavis]

Surround-delete works on the character pressed after md. There isn't any need to add future expressive power to surround-delete; you can use sub-selections (s) to achieve anything you would want with a regex or special characters.

[AceofSpades5757]

@the-mikedavis Thanks. Instead of a pop-up, some sort of indicator would be nice to show that Helix is waiting for additional input to finish the command.

[AceofSpades5757]

What about the keys, on the bottom-right of the window, staying until either an input, or canceling?

This is what it looks like after hitting m to open the Match context menu.

This character(s) is removed when pressing things like d for surround delete, or r for replace. It would be nice to leave these keys there to indicate that the user is still in the middle of a key sequence.

[the-mikedavis]

Pseudo-pending seems appropriate for this, especially since we use it elsewhere with m commands 👍

If you'd like to take a shot at this, the field is pseudo_pending: Option<String> and you can find an example usage in helix_term::commands::select_textobject.

[AceofSpades5757]

I'll take a crack at it.