refactor(#2826): split global View and instance Window

lua/nvim-tree.lua

@@ -1,4 +1,5 @@
 local log = require("nvim-tree.log")
+local view = require("nvim-tree.view")
 local utils = require("nvim-tree.utils")
 local actions = require("nvim-tree.actions")
 local core = require("nvim-tree.core")
@@ -73,8 +74,7 @@ function M.change_root(path, bufnr)
 end
 
 function M.tab_enter()
-  local explorer = core.get_explorer()
+  if view.is_visible({ any_tabpage = true }) then
-  if explorer and explorer.window:is_visible({ any_tabpage = true }) then
     local bufname = vim.api.nvim_buf_get_name(0)
 
     local ft
@@ -89,15 +89,17 @@ function M.tab_enter()
         return
       end
     end
-    explorer.window:open({ focus_tree = false })
 
+    local explorer = core.get_explorer()
+    if explorer then
+      explorer.window:open({ focus_tree = false })
       explorer.renderer:draw()
     end
   end
+end
 
 function M.open_on_directory()
-  local explorer = core.get_explorer()
+  local should_proceed = _config.hijack_directories.auto_open or view.is_visible()
-  local should_proceed = _config.hijack_directories.auto_open or explorer and explorer.window:is_visible()
   if not should_proceed then
     return
   end
@@ -668,7 +670,9 @@ function M.purge_all_state()
   local explorer = core.get_explorer()
   if explorer then
     explorer.window:close_all_tabs()
-    explorer.window:abandon_all_windows()
+  end
+  view.abandon_all_windows()
+  if explorer then
     require("nvim-tree.git").purge_state()
     explorer:destroy()
     core.reset_explorer()

lua/nvim-tree/actions/finders/find-file.lua

@@ -1,4 +1,5 @@
 local log = require("nvim-tree.log")
+local view = require("nvim-tree.view")
 local utils = require("nvim-tree.utils")
 local core = require("nvim-tree.core")
 
@@ -13,7 +14,7 @@ local running = {}
 ---@param path string relative or absolute
 function M.fn(path)
   local explorer = core.get_explorer()
-  if not explorer or not explorer.window:is_visible() then
+  if not explorer or not view.is_visible() then
     return
   end
 
@@ -83,9 +84,9 @@ function M.fn(path)
     end)
     :iterate()
 
-  if found and explorer.window:is_visible() then
+  if found and view.is_visible() then
     explorer.renderer:draw()
-    explorer.window:set_cursor({ line, 0 })
+    view.set_cursor({ line, 0 })
   end
 
   running[path_real] = false

lua/nvim-tree/actions/moves/item.lua

@@ -1,4 +1,5 @@
 local utils = require("nvim-tree.utils")
+local view = require("nvim-tree.view")
 local core = require("nvim-tree.core")
 local diagnostics = require("nvim-tree.diagnostics")
 
@@ -66,9 +67,9 @@ local function move(explorer, where, what, skip_gitignored)
   end
 
   if nex then
-    explorer.window:set_cursor({ nex, 0 })
+    view.set_cursor({ nex, 0 })
   elseif vim.o.wrapscan and first then
-    explorer.window:set_cursor({ first, 0 })
+    view.set_cursor({ first, 0 })
   end
 end
 
@@ -188,13 +189,13 @@ local function move_prev_recursive(explorer, what, skip_gitignored)
 
       -- 4.3)
       if node_init.name == ".." then -- root node
-        explorer.window:set_cursor({ 1, 0 })    -- move to root node (position 1)
+        view.set_cursor({ 1, 0 })    -- move to root node (position 1)
       else
         local node_init_line = utils.find_node_line(node_init)
         if node_init_line < 0 then
           return
         end
-        explorer.window:set_cursor({ node_init_line, 0 })
+        view.set_cursor({ node_init_line, 0 })
       end
 
       -- 4.4)

lua/nvim-tree/actions/moves/parent.lua

@@ -1,3 +1,4 @@
+local view = require("nvim-tree.view")
 local utils = require("nvim-tree.utils")
 
 local DirectoryNode = require("nvim-tree.node.directory")
@@ -24,7 +25,7 @@ function M.fn(should_close)
     local parent = (node:get_parent_of_group() or node).parent
 
     if not parent or not parent.parent then
-      node.explorer.window:set_cursor({ 1, 0 })
+      view.set_cursor({ 1, 0 })
       return
     end
 
@@ -32,7 +33,7 @@ function M.fn(should_close)
       return n.absolute_path == parent.absolute_path
     end)
 
-    node.explorer.window:set_cursor({ line + 1, 0 })
+    view.set_cursor({ line + 1, 0 })
     if should_close then
       parent.open = false
       parent.explorer.renderer:draw()

lua/nvim-tree/actions/node/open-file.lua

@@ -3,6 +3,7 @@ local lib = require("nvim-tree.lib")
 local notify = require("nvim-tree.notify")
 local utils = require("nvim-tree.utils")
 local core = require("nvim-tree.core")
+local view = require("nvim-tree.view")
 
 local M = {}
 
@@ -19,10 +20,9 @@ end
 ---Get all windows in the current tabpage that aren't NvimTree.
 ---@return table with valid win_ids
 local function usable_win_ids()
-  local explorer = core.get_explorer()
   local tabpage = vim.api.nvim_get_current_tabpage()
   local win_ids = vim.api.nvim_tabpage_list_wins(tabpage)
-  local tree_winid = explorer and explorer.window:get_winnr(tabpage)
+  local tree_winid = view.get_winnr(tabpage)
 
   return vim.tbl_filter(function(id)
     local bufid = vim.api.nvim_win_get_buf(id)
@@ -386,12 +386,7 @@ local function is_already_loaded(filename)
 end
 
 local function edit_in_current_buf(filename)
-  local explorer = core.get_explorer()
+  require("nvim-tree.view").abandon_current_window()
-
-  if explorer then
-    explorer.window:abandon_current_window()
-  end
-
   if M.relative_path then
     filename = utils.path_relative(filename, vim.fn.getcwd())
   end

lua/nvim-tree/actions/tree/find-file.lua

@@ -1,5 +1,6 @@
 local core = require("nvim-tree.core")
 local lib = require("nvim-tree.lib")
+local view = require("nvim-tree.view")
 local finders_find_file = require("nvim-tree.actions.finders.find-file")
 
 local M = {}
@@ -41,7 +42,7 @@ function M.fn(opts)
   end
 
   local explorer = core.get_explorer()
-  if explorer and explorer.window:is_visible() then
+  if explorer and view.is_visible() then
     -- focus
     if opts.focus then
       lib.set_target_win()

lua/nvim-tree/actions/tree/open.lua

@@ -1,5 +1,6 @@
 local core = require("nvim-tree.core")
 local lib = require("nvim-tree.lib")
+local view = require("nvim-tree.view")
 local finders_find_file = require("nvim-tree.actions.finders.find-file")
 
 local M = {}
@@ -25,7 +26,7 @@ function M.fn(opts)
 
   local explorer = core.get_explorer()
 
-  if explorer and explorer.window:is_visible() then
+  if explorer and view.is_visible() then
     -- focus
     lib.set_target_win()
     explorer.window:focus()

lua/nvim-tree/actions/tree/toggle.lua

@@ -1,5 +1,6 @@
 local core = require("nvim-tree.core")
 local lib = require("nvim-tree.lib")
+local view = require("nvim-tree.view")
 local finders_find_file = require("nvim-tree.actions.finders.find-file")
 
 local M = {}
@@ -42,7 +43,7 @@ function M.fn(opts, no_focus, cwd, bang)
     opts.path = nil
   end
 
-  if explorer and explorer.window:is_visible() then
+  if explorer and view.is_visible() then
     -- close
     explorer.window:close()
   else

lua/nvim-tree/api.lua

@@ -1,4 +1,5 @@
 local core = require("nvim-tree.core")
+local view = require("nvim-tree.view")
 local utils = require("nvim-tree.utils")
 local actions = require("nvim-tree.actions")
 local appearance_hi_test = require("nvim-tree.appearance.hi-test")
@@ -140,9 +141,9 @@ Api.tree.focus = Api.tree.open
 ---@field focus boolean|nil default true
 
 Api.tree.toggle = wrap(actions.tree.toggle.fn)
-Api.tree.close = wrap_explorer_member("view", "close")
+Api.tree.close = wrap_explorer_member("window", "close")
-Api.tree.close_in_this_tab = wrap_explorer_member("view", "close_this_tab_only")
+Api.tree.close_in_this_tab = wrap_explorer_member("window", "close_this_tab_only")
-Api.tree.close_in_all_tabs = wrap_explorer_member("view", "close_all_tabs")
+Api.tree.close_in_all_tabs = wrap_explorer_member("window", "close_all_tabs")
 Api.tree.reload = wrap_explorer("reload_explorer")
 
 ---@class ApiTreeResizeOpts
@@ -201,12 +202,12 @@ Api.tree.is_tree_buf = wrap(utils.is_nvim_tree_buf)
 ---@field tabpage number|nil
 ---@field any_tabpage boolean|nil default false
 
-Api.tree.is_visible = wrap_explorer_member("view", "is_visible")
+Api.tree.is_visible = wrap(view.is_visible)
 
 ---@class ApiTreeWinIdOpts
 ---@field tabpage number|nil default nil
 
-Api.tree.winid = wrap_explorer_member("view", "winid")
+Api.tree.winid = wrap(view.winid)
 
 Api.fs.create = wrap_node_or_nil(actions.fs.create_file.fn)
 Api.fs.remove = wrap_node(actions.fs.remove_file.fn)

lua/nvim-tree/diagnostics.lua

@@ -1,5 +1,6 @@
 local core = require("nvim-tree.core")
 local utils = require("nvim-tree.utils")
+local view = require("nvim-tree.view")
 local log = require("nvim-tree.log")
 
 local DirectoryNode = require("nvim-tree.node.directory")
@@ -181,15 +182,10 @@ function M.update_coc()
     end
     log.profile_end(profile)
 
-    local explorer = core.get_explorer()
+    local bufnr = view.get_bufnr()
-
-    local bufnr
-    if explorer then
-      bufnr = explorer.window:get_bufnr()
-    end
-
     local should_draw = bufnr and vim.api.nvim_buf_is_valid(bufnr) and vim.api.nvim_buf_is_loaded(bufnr)
     if should_draw then
+      local explorer = core.get_explorer()
       if explorer then
         explorer.renderer:draw()
       end

lua/nvim-tree/explorer/init.lua

@@ -4,6 +4,7 @@ local core = require("nvim-tree.core")
 local git = require("nvim-tree.git")
 local log = require("nvim-tree.log")
 local utils = require("nvim-tree.utils")
+local view = require("nvim-tree.view")
 local node_factory = require("nvim-tree.node.factory")
 
 local DirectoryNode = require("nvim-tree.node.directory")
@@ -176,7 +177,7 @@ function Explorer:create_autocmds()
       if self.opts.actions.open_file.eject then
         self.window:prevent_buffer_override()
       else
-        self.window:abandon_current_window()
+        view.abandon_current_window()
       end
     end,
   })
@@ -526,7 +527,7 @@ function Explorer:reload_explorer()
 
   local projects = git.reload_all_projects()
   self:refresh_nodes(projects)
-  if self.window:is_visible() then
+  if view.is_visible() then
     self.renderer:draw()
   end
   event_running = false
@@ -548,7 +549,7 @@ end
 ---nil on no explorer or invalid view win
 ---@return integer[]|nil
 function Explorer:get_cursor_position()
-  local winnr = self.window:get_winnr()
+  local winnr = view.get_winnr()
   if not winnr or not vim.api.nvim_win_is_valid(winnr) then
     return
   end

lua/nvim-tree/explorer/live-filter.lua

@@ -1,3 +1,4 @@
+local view = require("nvim-tree.view")
 local utils = require("nvim-tree.utils")
 
 local Class = require("nvim-tree.classic")
@@ -209,7 +210,7 @@ function LiveFilter:start_filtering()
   self.explorer.renderer:draw()
   local row = require("nvim-tree.core").get_nodes_starting_line() - 1
   local col = #self.prefix > 0 and #self.prefix - 1 or 1
-  self.explorer.window:set_cursor({ row, col })
+  view.set_cursor({ row, col })
   -- needs scheduling to let the cursor move before initializing the window
   vim.schedule(function()
     return create_overlay(self)

lua/nvim-tree/explorer/window.lua

@@ -3,6 +3,7 @@ local events = require("nvim-tree.events")
 local utils = require("nvim-tree.utils")
 local log = require("nvim-tree.log")
 local notify = require("nvim-tree.notify")
+local view = require("nvim-tree.view")
 
 local Class = require("nvim-tree.classic")
 
@@ -11,18 +12,10 @@ local Class = require("nvim-tree.classic")
 ---@field resize boolean|nil default true
 ---@field winid number|nil 0 or nil for current
 
-local M = {}
-
 local DEFAULT_MIN_WIDTH = 30
 local DEFAULT_MAX_WIDTH = -1
 local DEFAULT_PADDING = 1
 
--- TODO global, rework for multiinstance explorer
--- M.View retained for simpler change history
-M.View = {
-  tabpages = {}
-}
-
 ---@class (exact) Window: Class
 ---@field live_filter table
 ---@field side string
@@ -30,7 +23,6 @@ M.View = {
 ---@field private explorer Explorer
 ---@field private adaptive_size boolean
 ---@field private centralize_selection boolean
----@field private cursors table<integer, integer[]> as per vim.api.nvim_win_get_cursor
 ---@field private hide_root_folder boolean
 ---@field private winopts table
 ---@field private height integer
@@ -55,7 +47,6 @@ function Window:new(args)
   self.explorer                    = args.explorer
   self.adaptive_size               = false
   self.centralize_selection        = self.explorer.opts.view.centralize_selection
-  self.cursors                     = {}
   self.float                       = self.explorer.opts.view.float
   self.height                      = self.explorer.opts.view.height
   self.hide_root_folder            = self.explorer.opts.renderer.root_folder_label == false
@@ -90,18 +81,6 @@ function Window:destroy()
   self.explorer:log_destroy("Window")
 end
 
--- The initial state of a tab
-local tabinitial = {
-  -- The position of the cursor { line, column }
-  cursor = { 0, 0 },
-  -- The NvimTree window number
-  winnr = nil,
-}
-
--- TODO global, rework for multiinstance explorer
----@type table<integer, integer>
-local BUFNR_PER_TAB = {}
-
 ---@type { name: string, value: any }[]
 local BUFFER_OPTIONS = {
   { name = "bufhidden",  value = "wipe" },
@@ -112,44 +91,23 @@ local BUFFER_OPTIONS = {
   { name = "swapfile",   value = false },
 }
 
----@private
----@param bufnr integer
----@return boolean
-function Window:matches_bufnr(bufnr)
-  for _, b in pairs(BUFNR_PER_TAB) do
-    if b == bufnr then
-      return true
-    end
-  end
-  return false
-end
-
----@private
-function Window:wipe_rogue_buffer()
-  for _, bufnr in ipairs(vim.api.nvim_list_bufs()) do
-    if not self:matches_bufnr(bufnr) and utils.is_nvim_tree_buf(bufnr) then
-      pcall(vim.api.nvim_buf_delete, bufnr, { force = true })
-    end
-  end
-end
-
 ---@private
 ---@param bufnr integer|false|nil
 function Window:create_buffer(bufnr)
-  self:wipe_rogue_buffer()
+  view.wipe_rogue_buffer()
 
-  local tab = vim.api.nvim_get_current_tabpage()
+  local tab = view.create_buffer(bufnr)
-  BUFNR_PER_TAB[tab] = bufnr or vim.api.nvim_create_buf(false, false)
-  vim.api.nvim_buf_set_name(self:get_bufnr(), "NvimTree_" .. tab)
 
-  bufnr = self:get_bufnr()
+  vim.api.nvim_buf_set_name(view.get_bufnr(), "NvimTree_" .. tab)
+
+  bufnr = view.get_bufnr()
   for _, option in ipairs(BUFFER_OPTIONS) do
     vim.api.nvim_set_option_value(option.name, option.value, { buf = bufnr })
   end
 
-  require("nvim-tree.keymap").on_attach(self:get_bufnr())
+  require("nvim-tree.keymap").on_attach(view.get_bufnr())
 
-  events._dispatch_tree_attached_post(self:get_bufnr())
+  events._dispatch_tree_attached_post(view.get_bufnr())
 end
 
 ---@private
@@ -166,6 +124,7 @@ function Window:get_size(size)
   return math.floor(vim.o.columns * percent_as_decimal)
 end
 
+---@private
 ---@param size (fun():integer)|integer|nil
 ---@return integer
 function Window:get_width(size)
@@ -176,22 +135,9 @@ function Window:get_width(size)
   end
 end
 
-local move_tbl = {
-  left = "H",
-  right = "L",
-}
-
--- setup_tabpage sets up the initial state of a tab
----@private
----@param tabpage integer
-function Window:setup_tabpage(tabpage)
-  local winnr = vim.api.nvim_get_current_win()
-  M.View.tabpages[tabpage] = vim.tbl_extend("force", M.View.tabpages[tabpage] or tabinitial, { winnr = winnr })
-end
-
 ---@private
 function Window:set_window_options_and_buffer()
-  pcall(vim.api.nvim_command, "buffer " .. self:get_bufnr())
+  pcall(vim.api.nvim_command, "buffer " .. view.get_bufnr())
 
   if vim.fn.has("nvim-0.10") == 1 then
     local eventignore = vim.api.nvim_get_option_value("eventignore", {})
@@ -234,7 +180,7 @@ function Window:open_window()
     vim.api.nvim_command("vsp")
     self:reposition_window()
   end
-  self:setup_tabpage(vim.api.nvim_get_current_tabpage())
+  view.setup_tabpage(vim.api.nvim_get_current_tabpage())
   self:set_window_options_and_buffer()
 end
 
@@ -269,23 +215,14 @@ local function switch_buf_if_last_buf()
   end
 end
 
----save_tab_state saves any state that should be preserved across redraws.
----@private
----@param tabnr integer
-function Window:save_tab_state(tabnr)
-  local tabpage = tabnr or vim.api.nvim_get_current_tabpage()
-  self.cursors[tabpage] = vim.api.nvim_win_get_cursor(self:get_winnr(tabpage) or 0)
-end
-
----@private
 ---@param tabpage integer
-function Window:close_internal(tabpage)
+local function close(tabpage)
-  if not self:is_visible({ tabpage = tabpage }) then
+  if not view.is_visible({ tabpage = tabpage }) then
     return
   end
-  self:save_tab_state(tabpage)
+  view.save_tab_state(tabpage)
   switch_buf_if_last_buf()
-  local tree_win = self:get_winnr(tabpage)
+  local tree_win = view.get_winnr(tabpage)
   local current_win = vim.api.nvim_get_current_win()
   for _, win in pairs(vim.api.nvim_tabpage_list_wins(tabpage)) do
     if vim.api.nvim_win_get_config(win).relative == "" then
@@ -306,13 +243,13 @@ function Window:close_internal(tabpage)
 end
 
 function Window:close_this_tab_only()
-  self:close_internal(vim.api.nvim_get_current_tabpage())
+  close(vim.api.nvim_get_current_tabpage())
 end
 
 function Window:close_all_tabs()
-  for tabpage, _ in pairs(M.View.tabpages) do
+  view.all_tabs_callback(function(t)
-    self:close_internal(tabpage)
+    close(t)
-  end
+  end)
 end
 
 ---@param tabpage integer|nil
@@ -320,7 +257,7 @@ function Window:close(tabpage)
   if self.explorer.opts.tab.sync.close then
     self:close_all_tabs()
   elseif tabpage then
-    self:close_internal(tabpage)
+    close(tabpage)
   else
     self:close_this_tab_only()
   end
@@ -328,7 +265,7 @@ end
 
 ---@param options table|nil
 function Window:open(options)
-  if self:is_visible() then
+  if view.is_visible() then
     return
   end
 
@@ -351,12 +288,12 @@ end
 ---@private
 function Window:grow()
   local starts_at = self:is_root_folder_visible(require("nvim-tree.core").get_cwd()) and 1 or 0
-  local lines = vim.api.nvim_buf_get_lines(self:get_bufnr(), starts_at, -1, false)
+  local lines = vim.api.nvim_buf_get_lines(view.get_bufnr(), starts_at, -1, false)
   -- number of columns of right-padding to indicate end of path
   local padding = self:get_size(self.padding)
 
   -- account for sign/number columns etc.
-  local wininfo = vim.fn.getwininfo(self:get_winnr())
+  local wininfo = vim.fn.getwininfo(view.get_winnr())
   if type(wininfo) == "table" and type(wininfo[1]) == "table" then
     padding = padding + wininfo[1].textoff
   end
@@ -375,7 +312,7 @@ function Window:grow()
   for line_nr, l in pairs(lines) do
     local count = vim.fn.strchars(l)
     -- also add space for right-aligned icons
-    local extmarks = vim.api.nvim_buf_get_extmarks(self:get_bufnr(), ns_id, { line_nr, 0 }, { line_nr, -1 }, { details = true })
+    local extmarks = vim.api.nvim_buf_get_extmarks(view.get_bufnr(), ns_id, { line_nr, 0 }, { line_nr, -1 }, { details = true })
     count = count + utils.extmarks_length(extmarks)
     if resizing_width < count then
       resizing_width = count
@@ -421,11 +358,11 @@ function Window:resize(size)
     self.height = size
   end
 
-  if not self:is_visible() then
+  if not view.is_visible() then
     return
   end
 
-  local winnr = self:get_winnr() or 0
+  local winnr = view.get_winnr() or 0
 
   local new_size = self:get_width()
 
@@ -441,17 +378,10 @@ end
 
 ---@private
 function Window:reposition_window()
-  local move_to = move_tbl[self.side]
+  vim.api.nvim_command("wincmd " .. (self.side == "left" and "H" or "L"))
-  vim.api.nvim_command("wincmd " .. move_to)
   self:resize()
 end
 
----@private
-function Window:set_current_win()
-  local current_tab = vim.api.nvim_get_current_tabpage()
-  M.View.tabpages[current_tab].winnr = vim.api.nvim_get_current_win()
-end
-
 ---Open the tree in the a window
 ---@param opts OpenInWinOpts|nil
 function Window:open_in_win(opts)
@@ -461,8 +391,8 @@ function Window:open_in_win(opts)
     vim.api.nvim_set_current_win(opts.winid)
   end
   self:create_buffer(opts.hijack_current_buf and vim.api.nvim_get_current_buf())
-  self:setup_tabpage(vim.api.nvim_get_current_tabpage())
+  view.setup_tabpage(vim.api.nvim_get_current_tabpage())
-  self:set_current_win()
+  view.set_current_win()
   self:set_window_options_and_buffer()
   if opts.resize then
     self:reposition_window()
@@ -471,63 +401,16 @@ function Window:open_in_win(opts)
   events._dispatch_on_tree_open()
 end
 
-function Window:abandon_current_window()
-  local tab = vim.api.nvim_get_current_tabpage()
-  BUFNR_PER_TAB[tab] = nil
-  if M.View.tabpages[tab] then
-    M.View.tabpages[tab].winnr = nil
-  end
-end
-
-function Window:abandon_all_windows()
-  for tab, _ in pairs(vim.api.nvim_list_tabpages()) do
-    BUFNR_PER_TAB[tab] = nil
-    if M.View.tabpages[tab] then
-      M.View.tabpages[tab].winnr = nil
-    end
-  end
-end
-
----@param opts table|nil
----@return boolean
-function Window:is_visible(opts)
-  if opts and opts.tabpage then
-    if M.View.tabpages[opts.tabpage] == nil then
-      return false
-    end
-    local winnr = M.View.tabpages[opts.tabpage].winnr
-    return winnr and vim.api.nvim_win_is_valid(winnr)
-  end
-
-  if opts and opts.any_tabpage then
-    for _, v in pairs(M.View.tabpages) do
-      if v.winnr and vim.api.nvim_win_is_valid(v.winnr) then
-        return true
-      end
-    end
-    return false
-  end
-
-  return self:get_winnr() ~= nil and vim.api.nvim_win_is_valid(self:get_winnr() or 0)
-end
-
----@param opts table|nil
-function Window:set_cursor(opts)
-  if self:is_visible() then
-    pcall(vim.api.nvim_win_set_cursor, self:get_winnr(), opts)
-  end
-end
-
 ---@param winnr number|nil
 ---@param open_if_closed boolean|nil
 function Window:focus(winnr, open_if_closed)
-  local wnr = winnr or self:get_winnr()
+  local wnr = winnr or view.get_winnr()
 
   if vim.api.nvim_win_get_tabpage(wnr or 0) ~= vim.api.nvim_win_get_tabpage(0) then
     self:close()
     self:open()
-    wnr = self:get_winnr()
+    wnr = view.get_winnr()
-  elseif open_if_closed and not self:is_visible() then
+  elseif open_if_closed and not view.is_visible() then
     self:open()
   end
 
@@ -536,47 +419,9 @@ function Window:focus(winnr, open_if_closed)
   end
 end
 
---- Retrieve the winid of the open tree.
----@param opts ApiTreeWinIdOpts|nil
----@return number|nil winid unlike get_winnr(), this returns nil if the nvim-tree window is not visible
-function Window:winid(opts)
-  local tabpage = opts and opts.tabpage
-  if tabpage == 0 then
-    tabpage = vim.api.nvim_get_current_tabpage()
-  end
-  if self:is_visible({ tabpage = tabpage }) then
-    return self:get_winnr(tabpage)
-  else
-    return nil
-  end
-end
-
---- Restores the state of a NvimTree window if it was initialized before.
-function Window:restore_tab_state()
-  local tabpage = vim.api.nvim_get_current_tabpage()
-  self:set_cursor(self.cursors[tabpage])
-end
-
---- Returns the window number for nvim-tree within the tabpage specified
----@param tabpage number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
----@return number|nil
-function Window:get_winnr(tabpage)
-  tabpage = tabpage or vim.api.nvim_get_current_tabpage()
-  local tabinfo = M.View.tabpages[tabpage]
-  if tabinfo and tabinfo.winnr and vim.api.nvim_win_is_valid(tabinfo.winnr) then
-    return tabinfo.winnr
-  end
-end
-
---- Returns the current nvim tree bufnr
----@return number
-function Window:get_bufnr()
-  return BUFNR_PER_TAB[vim.api.nvim_get_current_tabpage()]
-end
-
 function Window:prevent_buffer_override()
-  local view_winnr = self:get_winnr()
+  local view_winnr = view.get_winnr()
-  local view_bufnr = self:get_bufnr()
+  local view_bufnr = view.get_bufnr()
 
   -- need to schedule to let the new buffer populate the window
   -- because this event needs to be run on bufWipeout.
@@ -588,12 +433,7 @@ function Window:prevent_buffer_override()
     local bufname = vim.api.nvim_buf_get_name(curbuf)
 
     if not bufname:match("NvimTree") then
-      for i, tabpage in ipairs(M.View.tabpages) do
+      view.clear_tabpage(view_winnr)
-        if tabpage.winnr == view_winnr then
-          M.View.tabpages[i] = nil
-          break
-        end
-      end
     end
     if curwin ~= view_winnr or bufname == "" or curbuf == view_bufnr then
       return
@@ -605,10 +445,7 @@ function Window:prevent_buffer_override()
     vim.cmd("setlocal nowinfixheight")
     self:open({ focus_tree = false })
 
-    local explorer = require("nvim-tree.core").get_explorer()
+    self.explorer.renderer:draw()
-    if explorer then
-      explorer.renderer:draw()
-    end
 
     pcall(vim.api.nvim_win_close, curwin, { force = true })
 
@@ -630,9 +467,9 @@ end
 
 -- used on ColorScheme event
 function Window:reset_winhl()
-  local winnr = self:get_winnr()
+  local winnr = view.get_winnr()
   if winnr and vim.api.nvim_win_is_valid(winnr) then
-    vim.wo[self:get_winnr()].winhl = appearance.WIN_HL
+    vim.wo[view.get_winnr()].winhl = appearance.WIN_HL
   end
 end
 

lua/nvim-tree/lib.lua

@@ -1,3 +1,4 @@
+local view = require("nvim-tree.view")
 local core = require("nvim-tree.core")
 local notify = require("nvim-tree.notify")
 
@@ -11,11 +12,9 @@ local M = {
 }
 
 function M.set_target_win()
-  local explorer = core.get_explorer()
-
   local id = vim.api.nvim_get_current_win()
-
+  local tree_id = view.get_winnr()
-  if explorer and id == explorer.window:get_winnr() then
+  if tree_id and id == tree_id then
     M.target_winid = 0
     return
   end
@@ -134,10 +133,7 @@ function M.open(opts)
   else
     open_view_and_draw()
   end
-
+  view.restore_tab_state()
-  if explorer then
-    explorer.window:restore_tab_state()
-  end
 end
 
 function M.setup(opts)

lua/nvim-tree/renderer/init.lua

@@ -1,4 +1,5 @@
 local log = require("nvim-tree.log")
+local view = require("nvim-tree.view")
 local events = require("nvim-tree.events")
 
 local Class = require("nvim-tree.classic")
@@ -101,28 +102,28 @@ function Renderer:render_hl(bufnr, hl_range_args)
 end
 
 function Renderer:draw()
-  local bufnr = self.explorer.window:get_bufnr()
+  local bufnr = view.get_bufnr()
   if not bufnr or not vim.api.nvim_buf_is_loaded(bufnr) then
     return
   end
 
   local profile = log.profile_start("draw")
 
-  local cursor = vim.api.nvim_win_get_cursor(self.explorer.window:get_winnr() or 0)
+  local cursor = vim.api.nvim_win_get_cursor(view.get_winnr() or 0)
 
   local builder = Builder(self.explorer):build()
 
   self:_draw(bufnr, builder.lines, builder.hl_range_args, builder.signs, builder.extmarks, builder.virtual_lines)
 
   if cursor and #builder.lines >= cursor[1] then
-    vim.api.nvim_win_set_cursor(self.explorer.window:get_winnr() or 0, cursor)
+    vim.api.nvim_win_set_cursor(view.get_winnr() or 0, cursor)
   end
 
   self.explorer.window:grow_from_content()
 
   log.profile_end(profile)
 
-  events._dispatch_on_tree_rendered(bufnr, self.explorer.window:get_winnr())
+  events._dispatch_on_tree_rendered(bufnr, view.get_winnr())
 end
 
 return Renderer

lua/nvim-tree/utils.lua

@@ -543,10 +543,7 @@ function M.focus_file(path)
   local _, i = M.find_node(require("nvim-tree.core").get_explorer().nodes, function(node)
     return node.absolute_path == path
   end)
-  local explorer = require("nvim-tree.core").get_explorer()
+  require("nvim-tree.view").set_cursor({ i + 1, 1 })
-  if explorer then
-    explorer.window:set_cursor({ i + 1, 1 })
-  end
 end
 
 ---Focus node passed as parameter if visible, otherwise focus first visible parent.
@@ -566,7 +563,7 @@ function M.focus_node_or_parent(node)
     end)
 
     if found_node or node.parent == nil then
-      explorer.window:set_cursor({ i + 1, 1 })
+      require("nvim-tree.view").set_cursor({ i + 1, 1 })
       break
     end
 

lua/nvim-tree/view.lua

@@ -0,0 +1,186 @@
+local utils = require("nvim-tree.utils")
+
+local M = {}
+
+M.View = {
+  tabpages             = {},
+  cursors              = {},
+}
+
+-- The initial state of a tab
+local tabinitial = {
+  -- The position of the cursor { line, column }
+  cursor = { 0, 0 },
+  -- The NvimTree window number
+  winnr = nil,
+}
+
+local BUFNR_PER_TAB = {}
+
+---@param bufnr integer
+---@return boolean
+local function matches_bufnr(bufnr)
+  for _, b in pairs(BUFNR_PER_TAB) do
+    if b == bufnr then
+      return true
+    end
+  end
+  return false
+end
+
+function M.wipe_rogue_buffer()
+  for _, bufnr in ipairs(vim.api.nvim_list_bufs()) do
+    if not matches_bufnr(bufnr) and utils.is_nvim_tree_buf(bufnr) then
+      pcall(vim.api.nvim_buf_delete, bufnr, { force = true })
+    end
+  end
+end
+
+---@param bufnr integer|boolean|nil
+---@return integer tab
+function M.create_buffer(bufnr)
+  local tab = vim.api.nvim_get_current_tabpage()
+  BUFNR_PER_TAB[tab] = bufnr or vim.api.nvim_create_buf(false, false)
+  return tab
+end
+
+-- setup_tabpage sets up the initial state of a tab
+---@param tabpage integer
+function M.setup_tabpage(tabpage)
+  local winnr = vim.api.nvim_get_current_win()
+  M.View.tabpages[tabpage] = vim.tbl_extend("force", M.View.tabpages[tabpage] or tabinitial, { winnr = winnr })
+end
+
+-- save_tab_state saves any state that should be preserved across redraws.
+---@param tabnr integer
+function M.save_tab_state(tabnr)
+  local tabpage = tabnr or vim.api.nvim_get_current_tabpage()
+  M.View.cursors[tabpage] = vim.api.nvim_win_get_cursor(M.get_winnr(tabpage) or 0)
+end
+
+---@param fn fun(tabpage: integer)
+function M.all_tabs_callback(fn)
+  for tabpage, _ in pairs(M.View.tabpages) do
+    fn(tabpage)
+  end
+end
+
+function M.set_current_win()
+  local current_tab = vim.api.nvim_get_current_tabpage()
+  M.View.tabpages[current_tab].winnr = vim.api.nvim_get_current_win()
+end
+
+function M.abandon_current_window()
+  local tab = vim.api.nvim_get_current_tabpage()
+  BUFNR_PER_TAB[tab] = nil
+  if M.View.tabpages[tab] then
+    M.View.tabpages[tab].winnr = nil
+  end
+end
+
+function M.abandon_all_windows()
+  for tab, _ in pairs(vim.api.nvim_list_tabpages()) do
+    BUFNR_PER_TAB[tab] = nil
+    if M.View.tabpages[tab] then
+      M.View.tabpages[tab].winnr = nil
+    end
+  end
+end
+
+---@param opts table|nil
+---@return boolean
+function M.is_visible(opts)
+  if opts and opts.tabpage then
+    if M.View.tabpages[opts.tabpage] == nil then
+      return false
+    end
+    local winnr = M.View.tabpages[opts.tabpage].winnr
+    return winnr and vim.api.nvim_win_is_valid(winnr)
+  end
+
+  if opts and opts.any_tabpage then
+    for _, v in pairs(M.View.tabpages) do
+      if v.winnr and vim.api.nvim_win_is_valid(v.winnr) then
+        return true
+      end
+    end
+    return false
+  end
+
+  return M.get_winnr() ~= nil and vim.api.nvim_win_is_valid(M.get_winnr() or 0)
+end
+
+---@param opts table|nil
+function M.set_cursor(opts)
+  if M.is_visible() then
+    pcall(vim.api.nvim_win_set_cursor, M.get_winnr(), opts)
+  end
+end
+
+--- Retrieve the winid of the open tree.
+---@param opts ApiTreeWinIdOpts|nil
+---@return number|nil winid unlike get_winnr(), this returns nil if the nvim-tree window is not visible
+function M.winid(opts)
+  local tabpage = opts and opts.tabpage
+  if tabpage == 0 then
+    tabpage = vim.api.nvim_get_current_tabpage()
+  end
+  if M.is_visible({ tabpage = tabpage }) then
+    return M.get_winnr(tabpage)
+  else
+    return nil
+  end
+end
+
+--- Restores the state of a NvimTree window if it was initialized before.
+function M.restore_tab_state()
+  local tabpage = vim.api.nvim_get_current_tabpage()
+  M.set_cursor(M.View.cursors[tabpage])
+end
+
+--- Returns the window number for nvim-tree within the tabpage specified
+---@param tabpage number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
+---@return number|nil
+function M.get_winnr(tabpage)
+  tabpage = tabpage or vim.api.nvim_get_current_tabpage()
+  local tabinfo = M.View.tabpages[tabpage]
+  if tabinfo and tabinfo.winnr and vim.api.nvim_win_is_valid(tabinfo.winnr) then
+    return tabinfo.winnr
+  end
+end
+
+--- Returns the current nvim tree bufnr
+---@return number
+function M.get_bufnr()
+  return BUFNR_PER_TAB[vim.api.nvim_get_current_tabpage()]
+end
+
+---@param winnr number|nil
+function M.clear_tabpage(winnr)
+  for i, tabpage in ipairs(M.View.tabpages) do
+    if tabpage.winnr == winnr then
+      M.View.tabpages[i] = nil
+      break
+    end
+  end
+end
+
+function M.setup(opts)
+  local options = opts.view or {}
+  M.View.centralize_selection = options.centralize_selection
+  M.View.side = (options.side == "right") and "right" or "left"
+  M.View.height = options.height
+  M.View.hide_root_folder = opts.renderer.root_folder_label == false
+  M.View.tab = opts.tab
+  M.View.preserve_window_proportions = options.preserve_window_proportions
+  M.View.winopts.cursorline = options.cursorline
+  M.View.winopts.number = options.number
+  M.View.winopts.relativenumber = options.relativenumber
+  M.View.winopts.signcolumn = options.signcolumn
+  M.View.float = options.float
+  M.on_attach = opts.on_attach
+
+  M.config = options
+end
+
+return M