feat: open tree on directory (#288)

lua/nvim-tree.lua

@@ -175,6 +175,21 @@ function M.print_clipboard()
   fs.print_clipboard()
 end
 
+function M.hijack_current_window()
+  local View = require'nvim-tree.view'.View
+  if not View.bufnr then
+    View.bufnr = api.nvim_get_current_buf()
+  end
+  local current_tab = api.nvim_get_current_tabpage()
+  if not View.tabpages then
+    View.tabpages = {
+      [current_tab] = { winnr = api.nvim_get_current_win() }
+    }
+  else
+    View.tabpages[current_tab] = { winnr = api.nvim_get_current_win() }
+  end
+end
+
 function M.on_enter()
   local bufnr = api.nvim_get_current_buf()
   local bufname = api.nvim_buf_get_name(bufnr)
@@ -195,6 +210,9 @@ function M.on_enter()
   local should_open = vim.g.nvim_tree_auto_open == 1
     and ((is_dir and netrw_disabled) or (bufname == "" and not buf_has_content))
     and not vim.tbl_contains(ft_ignore, buftype)
+  if bufname == '' or is_dir then
+    M.hijack_current_window()
+  end
   lib.init(should_open, should_open)
 end
 
@@ -260,6 +278,23 @@ local function update_root_dir()
   lib.change_dir(new_cwd)
 end
 
+function M.open_on_directory()
+  local buf = api.nvim_get_current_buf()
+  local bufname = api.nvim_buf_get_name(buf)
+  if vim.fn.isdirectory(bufname) ~= 1 or bufname == lib.Tree.cwd then
+    return
+  end
+
+  if view.win_open() and #api.nvim_list_wins() > 1 then
+    view.close()
+  end
+  M.hijack_current_window()
+  lib.change_dir(bufname)
+  lib.set_index_and_redraw(bufname)
+  view.focus()
+  view.replace_window()
+end
+
 function M.buf_enter()
   update_root_dir()
   if vim.g.nvim_tree_follow == 1 then