Setting buffer.tempfile = 'prompt.md' pushed prompt_toolkit into its
complex-tempfile path, which creates a temp dir and then calls
os.makedirs() on that same path when no subdirectory is present. That
raises EEXIST before the editor can launch.
Keep prompt_toolkit on the simple tempfile path with .md suffix, and
make the editor fallback chain explicit on both surfaces:
$VISUAL -> $EDITOR -> nvim -> vim -> vi -> nano.
prompt_toolkit's default editor list is: $VISUAL, $EDITOR, /usr/bin/editor,
/usr/bin/nano, /usr/bin/pico, /usr/bin/vi, /usr/bin/emacs — so when
neither env var is set, the base CLI launched nano. The TUI fell back
to a literal 'vi'. Same Ctrl+G keystroke, two different editors.
Pick the same chain on both surfaces:
$VISUAL → $EDITOR → vim → vi → nano
CLI: override input_area.buffer._open_file_in_editor on the TextArea
once at app build time. Local to that buffer; doesn't touch
os.environ or affect other subprocesses.
TUI: extract resolveEditor() into ui-tui/src/lib/editor.ts. PATH walk
with accessSync(X_OK), no shelling out. Six-line unit test verifies
the priority order and the multi-entry PATH walk.
Brooklyn Nicholson