Temporary Vi Mode in PowerShell

I miss the feature in readline (Bash/Zsh) where Ctrl+x, Ctrl+v switches to Vi command mode temporarily. In that workflow, entering Insert mode switches back to Emacs mode. PSReadLine has a command ViCommandMode, but binding it directly in Emacs mode will report errors on every key input.

The solution requires handling the mode change event to toggle the global EditMode between Emacs and Vi.

When entering “Insert” mode (the default for Emacs users), we force the mode to Emacs and set up the trigger for the temporary Vi mode. When that trigger (Ctrl+x, Ctrl+v) is fired, we switch the edit mode to Vi and jump to command mode.

Here is the configuration for your $PROFILE:

function OnViModeChange {
  if ($args[0] -eq 'Insert') {
    Set-PSReadLineOption -EditMode Emacs
    Set-PSReadlineKeyHandler -Chord "Ctrl+x,Ctrl+v" -ScriptBlock {
      Set-PSReadLineOption -EditMode Vi
      [Microsoft.PowerShell.PSConsoleReadLine]::ViCommandMode()
    }
    # Add other Emacs key bindings here.
    # Switching `EditMode` resets key bindings to their defaults.
    # Remember to reconfigure them.
    # Set-PSReadlineKeyHandler -Chord "Ctrl+w" -Function BackwardKillWord
  }
}
Set-PSReadLineOption -ViModeIndicator Script
Set-PSReadLineOption -ViModeChangeHandler $Function:OnViModeChange
Set-PSReadLineOption -EditMode Emacs
# Reuse the function to start Emacs mode
OnViModeChange Insert

Switching EditMode resets key bindings to their defaults. Remember to reconfigure them.