diff --git a/lua/lib/fs.lua b/lua/lib/fs.lua
index 5df4f830..13146988 100644
--- a/lua/lib/fs.lua
+++ b/lua/lib/fs.lua
@@ -129,7 +129,7 @@ local function do_copy(source, destination)
   luv.fs_mkdir(destination, source_stats.mode)
 
   while true do
-    local name, t = luv.fs_scandir_next(handle)
+    local name, _ = luv.fs_scandir_next(handle)
     if not name then break end
 
     local new_name = source..'/'..name
@@ -173,15 +173,15 @@ local function do_paste(node, action_type, action_fn)
     local dest_stats = luv.fs_stat(dest)
     local should_process = true
     if dest_stats then
-      local ans = vim.fn.input(dest..' already exists, overwrite ? y/n: ')
+      ans = vim.fn.input(dest..' already exists, overwrite ? y/n: ')
       clear_prompt()
       should_process = ans:match('^y')
     end
 
     if should_process then
-      local success, msg = action_fn(entry.absolute_path, dest)
+      local success, errmsg = action_fn(entry.absolute_path, dest)
       if not success then
-        api.nvim_err_writeln('Could not '..action_type..' '..entry.absolute_path..' - '..msg)
+        api.nvim_err_writeln('Could not '..action_type..' '..entry.absolute_path..' - '..errmsg)
       end
     end
   end
diff --git a/lua/lib/lib.lua b/lua/lib/lib.lua
index eebf02c4..118e9c37 100644
--- a/lua/lib/lib.lua
+++ b/lua/lib/lib.lua
@@ -19,7 +19,13 @@ M.Tree = {
   win_width =  vim.g.lua_tree_width or 30,
   loaded = false,
   bufnr = nil,
-  winnr = nil,
+  winnr = function()
+    for _, i in ipairs(api.nvim_list_wins()) do
+      if api.nvim_buf_get_name(api.nvim_win_get_buf(i)):match('.*/'..M.Tree.buf_name..'$') then
+        return i
+      end
+    end
+  end,
   buf_options = {
     'noswapfile',
   },
@@ -71,7 +77,7 @@ local function get_node_at_line(line)
 end
 
 function M.get_node_at_cursor()
-  local cursor = api.nvim_win_get_cursor(M.Tree.winnr)
+  local cursor = api.nvim_win_get_cursor(M.Tree.winnr())
   local line = cursor[1]
   if line == 1 and M.Tree.cwd ~= "/" then
     return { name = ".." }
@@ -169,7 +175,7 @@ function M.set_index_and_redraw(fname)
   end
   renderer.draw(M.Tree, reload)
   if index then
-    api.nvim_win_set_cursor(M.Tree.winnr, {index, 0})
+    api.nvim_win_set_cursor(M.Tree.winnr(), {index, 0})
   end
 end
 
@@ -246,23 +252,25 @@ local function create_win()
   api.nvim_command("wincmd "..window_opts.side)
   api.nvim_command("vertical resize "..M.Tree.win_width)
 
-  M.Tree.winnr = api.nvim_get_current_win()
+  local winnr = api.nvim_get_current_win()
 
   for opt, val in pairs(M.Tree.win_options) do
-    api.nvim_win_set_option(M.Tree.winnr, opt, val)
+    api.nvim_win_set_option(winnr, opt, val)
   end
 end
 
 function M.close()
-  api.nvim_win_close(M.Tree.winnr, true)
-  M.Tree.winnr = nil
+  if #api.nvim_list_wins() == 1 then
+    return vim.cmd ':q!'
+  end
+  api.nvim_win_close(M.Tree.winnr(), true)
   M.Tree.bufnr = nil
 end
 
 function M.open()
   create_buf()
   create_win()
-  api.nvim_win_set_buf(M.Tree.winnr, M.Tree.bufnr)
+  api.nvim_win_set_buf(M.Tree.winnr(), M.Tree.bufnr)
 
   for _, opt in pairs(M.Tree.buf_options) do
     api.nvim_command('setlocal '..opt)
@@ -276,12 +284,7 @@ function M.open()
 end
 
 function M.win_open()
-  for _, win in pairs(api.nvim_list_wins()) do
-    if win == M.Tree.winnr then
-      return true
-    end
-  end
-  return false
+  return M.Tree.winnr() ~= nil
 end
 
 function M.toggle_ignored()
diff --git a/lua/lib/populate.lua b/lua/lib/populate.lua
index 81480e05..20c4904d 100644
--- a/lua/lib/populate.lua
+++ b/lua/lib/populate.lua
@@ -129,7 +129,7 @@ function M.refresh_entries(entries, cwd)
   local change_prev
   for _, e in ipairs(all) do
     for _, name in ipairs(e.entries) do
-      chang_prev = true
+      change_prev = true
       if not named_entries[name] then
         local n = e.fn(cwd, name)
         if e.check(n.link_to, n.absolute_path) then
@@ -141,10 +141,10 @@ function M.refresh_entries(entries, cwd)
           entries_idx[name] = idx
           cached_entries[idx] = name
         else
-          chang_prev = false
+          change_prev = false
         end
       end
-      if chang_prev then prev = name end
+      if change_prev then prev = name end
     end
   end
 end
diff --git a/lua/lib/renderer.lua b/lua/lib/renderer.lua
index 1eb1a27c..590d6a84 100644
--- a/lua/lib/renderer.lua
+++ b/lua/lib/renderer.lua
@@ -92,7 +92,7 @@ local get_padding = function(depth)
 end
 
 if vim.g.lua_tree_indent_markers == 1 then
-  get_padding = function(depth, idx, tree, node, markers)
+  get_padding = function(depth, idx, tree, _, markers)
     local padding = ""
     if depth ~= 0 then
       local rdepth = depth/2