Problem

I'd like to replicate the full state of a terminal buffer so that the terminal can be restored from a Vim Session.vim file via nvim -S Session.vim later on.

Expected behavior

The types of data to consider for this are

• environment variables
• cd (which is often simply a function of $PWD)
• sub-shells
• virtual environments (sub-shell or not). e.g. Python virtualenv.
• terminal buffer variables. It seems plugins like toggleterm.nvim don't fully restore, though that might be my user error

Regarding sub-shells and virtual environments, I'd imagine both would require plugins to manage the specific details. But some sort of API to store list-of-commands so that interested plugins can add what they need that write to Session.vim and a means to load that data back would prevent needing to build one monolithic command that every plugin / tool has to play nice under.

In general it'd be a great improvement to get even one of these things though I have a feeling though most of this won't be possible because (if I remember correctly) Neovim isn't able to query that much from a started terminal such as environment variables. Is this request a pie in the sky? What do you think?