Opens nerdtree to the root of your current project if not looking at a file

vim/settings/yadr-keymap.vim

@@ -75,7 +75,15 @@ imap <C-a> <esc>wa
 
 " ==== NERD tree
 " Open the project tree and expose current file in the nerdtree with Ctrl-\
-nnoremap <silent> <C-\> :NERDTreeFind<CR>:vertical<CR>
+" " calls NERDTreeFind iff NERDTree is active, current window contains a modifiable file, and we're not in vimdiff
+function! OpenNerdTree()
+  if &modifiable && strlen(expand('%')) > 0 && !&diff
+    NERDTreeFind
+  else
+    NERDTreeToggle
+  endif
+endfunction
+nnoremap <silent> <C-\> :call OpenNerdTree()<CR>
 
 " ,q to toggle quickfix window (where you have stuff like Ag)
 " ,oq to open it back up (rare)