feat: Improve editor detection with auto-discovery and better error messages

[affaan-m]

Summary

Improves the /editor command UX by automatically detecting available editors and providing helpful error messages when none are found.

Changes

• Add GetEditor() utility function in packages/tui/internal/util/util.go:

  • Checks VISUAL environment variable first (standard for full-screen editors)
  • Falls back to EDITOR environment variable
  • Auto-detects common modern editors: VSCode (code), Cursor, Zed, Neovim (nvim), Vim, nano, vi
  • Platform-specific support (e.g., .cmd extensions and notepad.exe on Windows)

• Update /editor command (EditorOpenCommand) to use new detection

• Update /export command (SessionExportCommand) to use new detection

• Provide helpful error message: "No editor found. Set EDITOR environment variable (e.g., export EDITOR=vim)"

Testing

Tested scenarios:

• ✅ EDITOR set: uses specified editor
• ✅ VISUAL set: prefers VISUAL over EDITOR
• ✅ Neither set but common editor available: auto-detects (VSCode, Cursor, Neovim, Vim, Zed, etc.)
• ✅ No editor available: shows helpful error with instructions

Related Issues

Resolves the issue where users get unhelpful "No EDITOR set" message without guidance on how to fix it.

[rekram1-node]

/oc adjust GetEditor so there is never an error returned because it never returns an error so it doesnt need (string, error). Also for the commonEditors array lets reorder a bit, start with: vim, nvim, zed, then put everything else as is but flip the order between nano and vi (so nano should be last).

[opencode-agent]

Excellent! The changes have been successfully implemented. Here's a summary of what was done:

Changes Made

1. Modified GetEditor() function in packages/tui/internal/util/util.go:

   • Changed return type from (string, error) to just string
   • Removed all nil error returns since the function never returns an error
   • Reordered the commonEditors array to start with: vim, nvim, zed, then the rest
   • Flipped the order between nano and vi so nano is last
   • Updated Windows-specific editor list with the same reordering

2. Updated function calls in packages/tui/internal/tui/tui.go:

   • Removed error handling from both calls to GetEditor() (lines 1155 and 1401)
   • Changed from editor, err := util.GetEditor() to editor := util.GetEditor()
   • Kept the same empty string check logic since that still applies

The function now returns a simple string and never returns an error, making it cleaner to use while maintaining the same functionality for editor detection.

opencode session  |  github run

[rekram1-node]

thanks @affaan-m!