Plug 'preservim/nerdtree', { 'tag': '6.10.16' }

let g:NERDTreeDirArrowExpandable = '▸'
let g:NERDTreeDirArrowCollapsible = '▾'

let NERDTreeDirArrows=1

map <leader>nt :NERDTreeToggle<CR>

" Close nerdtree if it's the last buffer
autocmd BufEnter * if tabpagenr('$') == 1 && winnr('$') == 1 && exists('b:NERDTree') && b:NERDTree.isTabTree()
\ | quit
\ | endif

" Mirror nerdtree in each tab
autocmd BufWinEnter * silent NERDTreeMirror

" check if reading from stdin
autocmd StdinReadPre * let s:std_in=1

" open nerdtree if no args in passed to vim
autocmd VimEnter * if argc() == 0 && !exists('s:std_in') | NERDTree | wincmd p | endif

" open nerdtree if vim opens to a directory
autocmd VimEnter * if argc() == 1 && isdirectory(argv()[0]) && !exists('s:std_in')
\ | execute 'NERDTree' argv()[0]
\ | wincmd p
\ | enew
\ | execute 'cd '.argv()[0]
\ | endif