How to "enter" the selected folder in the vertical wildmenu?

Question

When using the vertical file/folder wild menu (ex: pressing Tab after :e or :cd ) and focused on a folder, is there a way to map a key to "move" inside that folder, and pick one of it's children ? If I press Enter, that is considered the "final answer", and the wildmenu is dismissed.

Answer 1

So after some trial and error, this seems to do the trick:

set wildcharm=<C-z>
cnoremap <Right> <Space><BS><Right><C-z>
cnoremap <expr> <Up> pumvisible() ? "\<C-p>" : "\<Up>"
cnoremap <expr> <Down> pumvisible() ? "\<C-n>" : "\<Down>"

• <Up>/<Down> selects the item above/below the currently selected one, when there is a menu open. If there is no menu, cycles between commands starting with the currently entered command (default behaviour)
• pressing <Right>:
  • with a folder selected: closes current menu, opens a new one with files/folders inside the previously selected folder, and selects the first item - but you can still use <Up>/<Down>/<Tab> to change the selected item, and if on a folder, can press <Right> to enter it
  • with a file selected: will simply close the menu - but you'll still have to confirm the choice by pressing Enter
• to finalise selection, press Enter

Tested in neovim v0.8.0-dev (6613f58ce); doesn't seem to be working in vim (8.1.3741)

Answer 2

By default the same keys are used for both horizontal and vertical menu. That is, <Left> and <Right> to move selection and <Up> and <Down> to move between levels.

For this reason, I'd rather recommend to set wop-=pum and stick to horizontal menu layout.