nushell: Cursor shape is stuck in vim when opening vim from a nushell

Describe the bug

When opening vim (or zsh or bash) from nushell, the cursor stays stuck to whatever it was in the nushell session (block or line cursor). Inside vim, switching between edit- and insert-mode doesn’t change the cursor either, which is very disorienting.

I even temporarily removed my ~/.vimrc file to make sure it’s not related to that.

How to reproduce

1. Open Apple Terminal app (I’m on macOS 13.5.1)
2. nu (if you’re not already in it)
3. vim (I used the macOS-supplied one at /usr/bin/vim)

Observe that cursor is a vertical line (or whatever it was you had nu’s cursor configured to). Pressing i puts me into insert mode but the cursor doesn’t change.

Expected behavior

I expect a block curstor in vim edit mode. More generally, I expect a program (like zsh or bash) when its opened from inside nu to be able to set its own cursor.

Screenshots

Configuration

key	value
version	0.84.0
branch
commit_hash
build_os	macos-aarch64
build_target	aarch64-apple-darwin
rust_version	rustc 1.71.1 (eb26296b5 2023-08-03) (built from a source tarball)
cargo_version	cargo 1.71.2 (1a737af0c 2023-08-07)
build_time	2023-08-22 21:09:23 +00:00
build_rust_channel	release
allocator	standard
features	dataframe, default, sqlite, trash, which, zip
installed_plugins

Additional context

Interestingly if I enter zsh from inside a nu shell, and then enter vim, the cursor is still broken. But if I enter vim directly from zsh (without going through nu) the cursor is correctly a block cursor.

This seems related to https://github.com/nushell/nushell/issues/8452, as I can get it fixed inside a zsh shell inside nu by resetting the cursor with echo -e "\033[2 q"

> nu
> zsh # cursor is still a line cursor here although usually it's a block cursor for me in zsh
> vim # line cursor
> echo -e "\033[2 q"
>
> vim # cursor is block now (both in insert mode and edit mode though)

---

Finally, If I put the following into my config.nu, the cursor is always a block cursor inside vim as well (in both insert and edit mode):

  edit_mode: vi,
  cursor_shape: {
    vi_insert: block,
    vi_normal: block,
  },

So definitely seems to have something to do with how nu shell sets the cursor. Seems whatever it’s doing should be undone before entering vim and before exiting nushell?