From 6e7ce8771bc41ac90c4f1651cf0018aa2d524e30 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Thu, 19 Jun 2025 16:25:32 +1000
Subject: [PATCH 01/17] refactor(#2826): fuller error messages

---
 lua/nvim-tree/explorer/view.lua | 70 ++++++++++++++++-----------------
 1 file changed, 35 insertions(+), 35 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 627364a4e40..5afdbb90f87 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -638,45 +638,46 @@ end
 ---@param callsite string
 ---@return number|nil
 function View:get_winnr(tabpage, callsite)
-  if self.explorer.opts.experimental.multi_instance then
-    local msg = string.format("View:get_winnr(%3s, %-20.20s)", tabpage, callsite)
-
-    tabpage = tabpage or vim.api.nvim_get_current_tabpage()
-    local tabinfo = globals.TABPAGES[tabpage]
-
-    local ret = nil
+  local tabid = tabpage or vim.api.nvim_get_current_tabpage()
+  local tabinfo = globals.TABPAGES[tabid]
+  local tabinfo_winid = nil
 
+  if self.explorer.opts.experimental.multi_instance then
+    local msg_fault = ""
     if not tabinfo then
-      msg = string.format("%s t%d no tabinfo", msg, tabpage)
+      msg_fault = "no tabinfo"
     elseif not tabinfo.winnr then
-      msg = string.format("%s t%d no tabinfo.winnr", msg, tabpage)
+      msg_fault = "no tabinfo.winnr"
     elseif not vim.api.nvim_win_is_valid(tabinfo.winnr) then
-      msg = string.format("%s t%d invalid tabinfo.winnr %d", msg, tabpage, tabinfo.winnr)
+      msg_fault = string.format("invalid tabinfo.winnr %d", tabinfo.winnr)
     else
-      msg = string.format("%s t%d w%d", msg, tabpage, tabinfo.winnr)
-      ret = tabinfo.winnr
+      tabinfo_winid = tabinfo.winnr
     end
 
-    local winid = self:winid(tabpage, "View:get_winnr")
-    if ret ~= winid then
-      if ret then
-        msg = string.format("%s winid_from_bufnr w%s MISMATCH", msg, winid)
-      else
-        msg = string.format("%s winid_from_bufnr w%s STALE", msg, winid)
-      end
-      notify.error(string.format("View:get_winnr w%s View:winnr w%s MISMATCH", ret, winid))
+    local winid = self:winid(tabid, "View:get_winnr")
+
+    if winid ~= tabinfo_winid then
+      msg_fault = "MISMATCH"
     end
 
+    local msg = string.format("View:get_winnr(%3s, %-20.20s) globals.TABPAGES[%s].winnr=w%s view.winid(%s)=w%s %s",
+      tabpage,
+      callsite,
+      tabid, tabinfo_winid,
+      tabid, winid,
+      msg_fault
+    )
+
     log.line("dev", "%s", msg)
 
-    return ret
-  else
-    tabpage = tabpage or vim.api.nvim_get_current_tabpage()
-    local tabinfo = globals.TABPAGES[tabpage]
-    if tabinfo and tabinfo.winnr and vim.api.nvim_win_is_valid(tabinfo.winnr) then
-      return tabinfo.winnr
+    if winid ~= tabinfo_winid then
+      notify.error(msg)
     end
   end
+
+  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
@@ -685,19 +686,18 @@ end
 function View:get_bufnr(callsite)
   local tab = vim.api.nvim_get_current_tabpage()
   if self.explorer.opts.experimental.multi_instance then
-    log.line("dev", "View:get_bufnr(%-20.20s) t%d global b%s member b%s %s",
+    local msg = string.format("View:get_bufnr(%-20.20s) globals.BUFNR_PER_TAB[%s]=b%s view.bufnr_by_tab[%s]=b%s MISMATCH",
       callsite,
-      tab,
-      globals.BUFNR_PER_TAB[tab],
-      self.bufnr_by_tab[tab],
-      (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH")
+      tab, globals.BUFNR_PER_TAB[tab],
+      tab, self.bufnr_by_tab[tab],
+      (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH"
+    )
 
     if globals.BUFNR_PER_TAB[tab] ~= self.bufnr_by_tab[tab] then
-      notify.error(string.format("View:get_bufnr globals.BUFNR_PER_TAB[%s] b%s view.bufnr_by_tab[%s] b%s MISMATCH",
-        tab, globals.BUFNR_PER_TAB[tab],
-        tab, self.bufnr_by_tab[tab]
-      ))
+      notify.error(msg)
     end
+
+    log.line("dev", msg)
   end
   return globals.BUFNR_PER_TAB[tab]
 end

From b7e97898502c67839074443be4fe7b4e8cec8df2 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Thu, 19 Jun 2025 16:44:19 +1000
Subject: [PATCH 02/17] refactor(#2826): winnr->winid in view/globals, remove
 redundant get_winid and get_bufnr calls

---
 lua/nvim-tree/actions/node/open-file.lua |   2 +-
 lua/nvim-tree/explorer/init.lua          |   2 +-
 lua/nvim-tree/explorer/view.lua          | 101 ++++++++++++-----------
 lua/nvim-tree/lib.lua                    |   2 +-
 lua/nvim-tree/renderer/init.lua          |   7 +-
 5 files changed, 59 insertions(+), 55 deletions(-)

diff --git a/lua/nvim-tree/actions/node/open-file.lua b/lua/nvim-tree/actions/node/open-file.lua
index dedd61229e5..b3bcce75a5a 100644
--- a/lua/nvim-tree/actions/node/open-file.lua
+++ b/lua/nvim-tree/actions/node/open-file.lua
@@ -22,7 +22,7 @@ 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.view:get_winnr(tabpage, "open-file.usable_win_ids")
+  local tree_winid = explorer and explorer.view:get_winid(tabpage, "open-file.usable_win_ids")
 
   return vim.tbl_filter(function(id)
     local bufid = vim.api.nvim_win_get_buf(id)
diff --git a/lua/nvim-tree/explorer/init.lua b/lua/nvim-tree/explorer/init.lua
index ca8c6d39103..6625d5b0870 100644
--- a/lua/nvim-tree/explorer/init.lua
+++ b/lua/nvim-tree/explorer/init.lua
@@ -554,7 +554,7 @@ end
 ---nil on no explorer or invalid view win
 ---@return integer[]|nil
 function Explorer:get_cursor_position()
-  local winnr = self.view:get_winnr(nil, "Explorer:get_cursor_position")
+  local winnr = self.view:get_winid(nil, "Explorer:get_cursor_position")
   if not winnr or not vim.api.nvim_win_is_valid(winnr) then
     return
   end
diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 5afdbb90f87..f0465192322 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -88,7 +88,7 @@ local tabinitial = {
   -- The position of the cursor { line, column }
   cursor = { 0, 0 },
   -- The NvimTree window number
-  winnr = nil,
+  winid = nil,
 }
 
 ---@type { name: string, value: any }[]
@@ -134,16 +134,17 @@ function View:create_buffer(bufnr)
     self.bufnr_by_tab[tab] = globals.BUFNR_PER_TAB[tab]
   end
 
-  vim.api.nvim_buf_set_name(self:get_bufnr("View:create_buffer1"), "NvimTree_" .. tab)
+  bufnr = self:get_bufnr("View:create_buffer")
+
+  vim.api.nvim_buf_set_name(bufnr, "NvimTree_" .. tab)
 
-  bufnr = self:get_bufnr("View:create_buffer2")
   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("View:create_buffer3"))
+  require("nvim-tree.keymap").on_attach(bufnr)
 
-  events._dispatch_tree_attached_post(self:get_bufnr("View:create_buffer4"))
+  events._dispatch_tree_attached_post(bufnr)
 end
 
 ---@private
@@ -180,17 +181,17 @@ local move_tbl = {
 ---@param tabpage integer
 ---@param callsite string
 function View:setup_tabpage(tabpage, callsite)
-  local winnr = vim.api.nvim_get_current_win()
+  local winid = vim.api.nvim_get_current_win()
 
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:setup_tabpage(%3s, %-20.20s) w%d %s",
       tabpage,
       callsite,
-      winnr,
+      winid,
       globals.TABPAGES[tabpage] and vim.inspect(globals.TABPAGES[tabpage], { newline = "" }) or "tabinitial")
   end
 
-  globals.TABPAGES[tabpage] = vim.tbl_extend("force", globals.TABPAGES[tabpage] or tabinitial, { winnr = winnr })
+  globals.TABPAGES[tabpage] = vim.tbl_extend("force", globals.TABPAGES[tabpage] or tabinitial, { winid = winid })
 end
 
 ---@private
@@ -278,7 +279,7 @@ end
 ---@param tabnr integer
 function View:save_tab_state(tabnr)
   local tabpage = tabnr or vim.api.nvim_get_current_tabpage()
-  globals.CURSORS[tabpage] = vim.api.nvim_win_get_cursor(self:get_winnr(tabpage, "View:save_tab_state") or 0)
+  globals.CURSORS[tabpage] = vim.api.nvim_win_get_cursor(self:get_winid(tabpage, "View:save_tab_state") or 0)
 end
 
 ---@private
@@ -292,7 +293,7 @@ function View:close_internal(tabpage)
   end
   self:save_tab_state(tabpage)
   switch_buf_if_last_buf()
-  local tree_win = self:get_winnr(tabpage, "View:close_internal")
+  local tree_win = self:get_winid(tabpage, "View:close_internal")
   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
@@ -371,7 +372,7 @@ function View:grow()
   local padding = self:get_size(self.padding)
 
   -- account for sign/number columns etc.
-  local wininfo = vim.fn.getwininfo(self:get_winnr(nil, "View:grow"))
+  local wininfo = vim.fn.getwininfo(self:get_winid(nil, "View:grow"))
   if type(wininfo) == "table" and type(wininfo[1]) == "table" then
     padding = padding + wininfo[1].textoff
   end
@@ -440,12 +441,12 @@ function View:resize(size)
     return
   end
 
-  local winnr = self:get_winnr(nil, "View:resize") or 0
+  local winid = self:get_winid(nil, "View:resize") or 0
 
   local new_size = self:get_width()
 
-  if new_size ~= vim.api.nvim_win_get_width(winnr) then
-    vim.api.nvim_win_set_width(winnr, new_size)
+  if new_size ~= vim.api.nvim_win_get_width(winid) then
+    vim.api.nvim_win_set_width(winid, new_size)
     if not self.preserve_window_proportions then
       vim.cmd(":wincmd =")
     end
@@ -471,13 +472,13 @@ function View:set_current_win(callsite)
     log.line("dev", "View:set_current_win(%-20.20s) t%d w%3s->w%3s %s",
       callsite,
       current_tab,
-      globals.TABPAGES[current_tab].winnr,
+      globals.TABPAGES[current_tab].winid,
       current_win,
-      (globals.TABPAGES[current_tab].winnr == current_win) and "" or "MISMATCH"
+      (globals.TABPAGES[current_tab].winid == current_win) and "" or "MISMATCH"
     )
   end
 
-  globals.TABPAGES[current_tab].winnr = current_win
+  globals.TABPAGES[current_tab].winid = current_win
 end
 
 ---Open the tree in the a window
@@ -505,7 +506,7 @@ function View:abandon_current_window()
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:abandon_current_window() t%d w%s b%s member b%s %s",
       tab,
-      globals.TABPAGES[tab] and globals.TABPAGES[tab].winnr or nil,
+      globals.TABPAGES[tab] and globals.TABPAGES[tab].winid or nil,
       globals.BUFNR_PER_TAB[tab],
       self.bufnr_by_tab[tab],
       (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH")
@@ -517,7 +518,7 @@ function View:abandon_current_window()
 
   globals.BUFNR_PER_TAB[tab] = nil
   if globals.TABPAGES[tab] then
-    globals.TABPAGES[tab].winnr = nil
+    globals.TABPAGES[tab].winid = nil
   end
 end
 
@@ -528,7 +529,7 @@ function View:abandon_all_windows(callsite)
       log.line("dev", "View:abandon_all_windows(%-20.20s) t%d w%s b%s member b%s %s",
         callsite,
         tab,
-        globals.TABPAGES and globals.TABPAGES.winnr or nil,
+        globals.TABPAGES and globals.TABPAGES.winid or nil,
         globals.BUFNR_PER_TAB[tab],
         self.bufnr_by_tab[tab],
         (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH")
@@ -538,7 +539,7 @@ function View:abandon_all_windows(callsite)
 
     globals.BUFNR_PER_TAB[tab] = nil
     if globals.TABPAGES[tab] then
-      globals.TABPAGES[tab].winnr = nil
+      globals.TABPAGES[tab].winid = nil
     end
   end
 end
@@ -550,38 +551,39 @@ function View:is_visible(opts)
     if globals.TABPAGES[opts.tabpage] == nil then
       return false
     end
-    local winnr = globals.TABPAGES[opts.tabpage].winnr
-    return winnr and vim.api.nvim_win_is_valid(winnr)
+    local winid = globals.TABPAGES[opts.tabpage].winid
+    return winid and vim.api.nvim_win_is_valid(winid)
   end
 
   if opts and opts.any_tabpage then
     for _, v in pairs(globals.TABPAGES) do
-      if v.winnr and vim.api.nvim_win_is_valid(v.winnr) then
+      if v.winid and vim.api.nvim_win_is_valid(v.winid) then
         return true
       end
     end
     return false
   end
 
-  return self:get_winnr(nil, "View:is_visible1") ~= nil and vim.api.nvim_win_is_valid(self:get_winnr(nil, "View:is_visible2") or 0)
+  local winid = self:get_winid(nil, "View:is_visible")
+  return winid ~= nil and vim.api.nvim_win_is_valid(winid or 0)
 end
 
 ---@param opts table|nil
 function View:set_cursor(opts)
   if self:is_visible() then
-    pcall(vim.api.nvim_win_set_cursor, self:get_winnr(nil, "View:set_cursor"), opts)
+    pcall(vim.api.nvim_win_set_cursor, self:get_winid(nil, "View:set_cursor"), opts)
   end
 end
 
----@param winnr number|nil
+---@param winid number|nil
 ---@param open_if_closed boolean|nil
-function View:focus(winnr, open_if_closed)
-  local wnr = winnr or self:get_winnr(nil, "View:focus1")
+function View:focus(winid, open_if_closed)
+  local wnr = winid or self:get_winid(nil, "View:focus1")
 
   if vim.api.nvim_win_get_tabpage(wnr or 0) ~= vim.api.nvim_win_get_tabpage(0) then
     self:close(nil, "View:focus")
     self:open()
-    wnr = self:get_winnr(nil, "View:focus2")
+    wnr = self:get_winid(nil, "View:focus2")
   elseif open_if_closed and not self:is_visible() then
     self:open()
   end
@@ -593,14 +595,14 @@ 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
+---@return number|nil winid unlike get_winid(), this returns nil if the nvim-tree window is not visible
 function View:api_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, "View:winid")
+    return self:get_winid(tabpage, "View:winid")
   else
     return nil
   end
@@ -637,7 +639,7 @@ end
 ---@param tabpage number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
 ---@param callsite string
 ---@return number|nil
-function View:get_winnr(tabpage, callsite)
+function View:get_winid(tabpage, callsite)
   local tabid = tabpage or vim.api.nvim_get_current_tabpage()
   local tabinfo = globals.TABPAGES[tabid]
   local tabinfo_winid = nil
@@ -646,21 +648,21 @@ function View:get_winnr(tabpage, callsite)
     local msg_fault = ""
     if not tabinfo then
       msg_fault = "no tabinfo"
-    elseif not tabinfo.winnr then
-      msg_fault = "no tabinfo.winnr"
-    elseif not vim.api.nvim_win_is_valid(tabinfo.winnr) then
-      msg_fault = string.format("invalid tabinfo.winnr %d", tabinfo.winnr)
+    elseif not tabinfo.winid then
+      msg_fault = "no tabinfo.winid"
+    elseif not vim.api.nvim_win_is_valid(tabinfo.winid) then
+      msg_fault = string.format("invalid tabinfo.winid %d", tabinfo.winid)
     else
-      tabinfo_winid = tabinfo.winnr
+      tabinfo_winid = tabinfo.winid
     end
 
-    local winid = self:winid(tabid, "View:get_winnr")
+    local winid = self:winid(tabid, "View:get_winid")
 
     if winid ~= tabinfo_winid then
       msg_fault = "MISMATCH"
     end
 
-    local msg = string.format("View:get_winnr(%3s, %-20.20s) globals.TABPAGES[%s].winnr=w%s view.winid(%s)=w%s %s",
+    local msg = string.format("View:get_winid(%3s, %-20.20s) globals.TABPAGES[%s].winid=w%s view.winid(%s)=w%s %s",
       tabpage,
       callsite,
       tabid, tabinfo_winid,
@@ -675,8 +677,9 @@ function View:get_winnr(tabpage, callsite)
     end
   end
 
-  if tabinfo and tabinfo.winnr and vim.api.nvim_win_is_valid(tabinfo.winnr) then
-    return tabinfo.winnr
+  -- legacy codepath
+  if tabinfo and tabinfo.winid and vim.api.nvim_win_is_valid(tabinfo.winid) then
+    return tabinfo.winid
   end
 end
 
@@ -703,7 +706,7 @@ function View:get_bufnr(callsite)
 end
 
 function View:prevent_buffer_override()
-  local view_winnr = self:get_winnr(nil, "View:prevent_buffer_override")
+  local view_winid = self:get_winid(nil, "View:prevent_buffer_override")
   local view_bufnr = self:get_bufnr("View:prevent_buffer_override")
 
   -- need to schedule to let the new buffer populate the window
@@ -717,9 +720,9 @@ function View:prevent_buffer_override()
 
     if not bufname:match("NvimTree") then
       for i, tabpage in ipairs(globals.TABPAGES) do
-        if tabpage.winnr == view_winnr then
+        if tabpage.winid == view_winid then
           if self.explorer.opts.experimental.multi_instance then
-            log.line("dev", "View:prevent_buffer_override() t%d w%d clearing", i, view_winnr)
+            log.line("dev", "View:prevent_buffer_override() t%d w%d clearing", i, view_winid)
           end
 
           globals.TABPAGES[i] = nil
@@ -727,7 +730,7 @@ function View:prevent_buffer_override()
         end
       end
     end
-    if curwin ~= view_winnr or bufname == "" or curbuf == view_bufnr then
+    if curwin ~= view_winid or bufname == "" or curbuf == view_bufnr then
       return
     end
 
@@ -762,9 +765,9 @@ end
 
 -- used on ColorScheme event
 function View:reset_winhl()
-  local winnr = self:get_winnr(nil, "View:reset_winhl1")
-  if winnr and vim.api.nvim_win_is_valid(winnr) then
-    vim.wo[self:get_winnr(nil, "View:reset_winhl2")].winhl = appearance.WIN_HL
+  local winid = self:get_winid(nil, "View:reset_winhl1")
+  if winid and vim.api.nvim_win_is_valid(winid) then
+    vim.wo[winid].winhl = appearance.WIN_HL
   end
 end
 
diff --git a/lua/nvim-tree/lib.lua b/lua/nvim-tree/lib.lua
index 20fe23dbdd4..cd6442cc044 100644
--- a/lua/nvim-tree/lib.lua
+++ b/lua/nvim-tree/lib.lua
@@ -15,7 +15,7 @@ function M.set_target_win()
 
   local id = vim.api.nvim_get_current_win()
 
-  if explorer and id == explorer.view:get_winnr(nil, "lib.set_target_win") then
+  if explorer and id == explorer.view:get_winid(nil, "lib.set_target_win") then
     M.target_winid = 0
     return
   end
diff --git a/lua/nvim-tree/renderer/init.lua b/lua/nvim-tree/renderer/init.lua
index f782973726a..99ac61b508b 100644
--- a/lua/nvim-tree/renderer/init.lua
+++ b/lua/nvim-tree/renderer/init.lua
@@ -105,24 +105,25 @@ function Renderer:draw()
   if not bufnr or not vim.api.nvim_buf_is_loaded(bufnr) then
     return
   end
+  local winid = self.explorer.view:get_winid(nil, "Renderer:draw")
 
   local profile = log.profile_start("draw")
 
-  local cursor = vim.api.nvim_win_get_cursor(self.explorer.view:get_winnr(nil, "Renderer:draw1") or 0)
+  local cursor = vim.api.nvim_win_get_cursor(winid 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.view:get_winnr(nil, "Renderer:draw2") or 0, cursor)
+    vim.api.nvim_win_set_cursor(winid or 0, cursor)
   end
 
   self.explorer.view:grow_from_content()
 
   log.profile_end(profile)
 
-  events._dispatch_on_tree_rendered(bufnr, self.explorer.view:get_winnr(nil, "Renderer:draw3"))
+  events._dispatch_on_tree_rendered(bufnr, winid)
 end
 
 return Renderer

From d6cd465462890e473e8ace7cce5f9bcc14cdbe8b Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Thu, 19 Jun 2025 16:46:27 +1000
Subject: [PATCH 03/17] refactor(#2826): winnr->winid consistently

---
 lua/nvim-tree/explorer/view.lua        | 10 +++++-----
 lua/nvim-tree/multi-instance-debug.lua | 14 +++++++-------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index f0465192322..896a5b666ec 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -578,18 +578,18 @@ end
 ---@param winid number|nil
 ---@param open_if_closed boolean|nil
 function View:focus(winid, open_if_closed)
-  local wnr = winid or self:get_winid(nil, "View:focus1")
+  local wid = winid or self:get_winid(nil, "View:focus1")
 
-  if vim.api.nvim_win_get_tabpage(wnr or 0) ~= vim.api.nvim_win_get_tabpage(0) then
+  if vim.api.nvim_win_get_tabpage(wid or 0) ~= vim.api.nvim_win_get_tabpage(0) then
     self:close(nil, "View:focus")
     self:open()
-    wnr = self:get_winid(nil, "View:focus2")
+    wid = self:get_winid(nil, "View:focus2")
   elseif open_if_closed and not self:is_visible() then
     self:open()
   end
 
-  if wnr then
-    vim.api.nvim_set_current_win(wnr)
+  if wid then
+    vim.api.nvim_set_current_win(wid)
   end
 end
 
diff --git a/lua/nvim-tree/multi-instance-debug.lua b/lua/nvim-tree/multi-instance-debug.lua
index 5b4604837cd..d33f34a1313 100644
--- a/lua/nvim-tree/multi-instance-debug.lua
+++ b/lua/nvim-tree/multi-instance-debug.lua
@@ -3,7 +3,7 @@ local globals = require("nvim-tree.globals")
 local M = {}
 
 --- Debugging only.
---- Tabs show TABPAGES winnr and BUFNR_PER_TAB bufnr for the tab.
+--- Tabs show TABPAGES winid and BUFNR_PER_TAB bufnr for the tab.
 --- Orphans for inexistent tab_ids are shown at the right.
 --- lib.target_winid is always shown at the right next to a close button.
 --- Enable with:
@@ -33,10 +33,10 @@ function M.tab_line()
     -- tab_id itself
     tl = tl .. " t" .. tab_id
 
-    -- winnr, if present
+    -- winid, if present
     local tp = globals.TABPAGES[tab_id]
     if tp then
-      tl = tl .. " w" .. (tp.winnr or "nil")
+      tl = tl .. " w" .. (tp.winid or "nil")
     else
       tl = tl .. "      "
     end
@@ -67,7 +67,7 @@ function M.tab_line()
   end
   for tab_id, tp in pairs(tabpages) do
     orphans[tab_id] = orphans[tab_id] or {}
-    orphans[tab_id].winnr = tp.winnr
+    orphans[tab_id].winid = tp.winid
   end
 
   -- right-align
@@ -78,9 +78,9 @@ function M.tab_line()
     -- inexistent tab
     tl = tl .. "%#error#| t" .. tab_id
 
-    -- maybe winnr
-    if orphan.winnr then
-      tl = tl .. " w" .. (orphan.winnr or "nil")
+    -- maybe winid
+    if orphan.winid then
+      tl = tl .. " w" .. (orphan.winid or "nil")
     else
       tl = tl .. "      "
     end

From de2ae0b06f447d75e8c1d6434a40b404dc394090 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 08:32:40 +1000
Subject: [PATCH 04/17] refactor(#2826): consistent use of buffer registry,
 tidy, add todos

---
 lua/nvim-tree/explorer/init.lua |  3 +++
 lua/nvim-tree/explorer/view.lua | 43 ++++++++++++++++++---------------
 2 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/lua/nvim-tree/explorer/init.lua b/lua/nvim-tree/explorer/init.lua
index 6625d5b0870..54b30c60057 100644
--- a/lua/nvim-tree/explorer/init.lua
+++ b/lua/nvim-tree/explorer/init.lua
@@ -85,6 +85,9 @@ function Explorer:destroy()
   self.sorters:destroy()
   self.view:destroy()
 
+  -- TODO existing buffer is retained by global and re-used. Delete it or retain it.
+  -- see wipe_rogue_buffer
+
   vim.api.nvim_del_augroup_by_id(self.augroup_id)
 
   RootNode.destroy(self)
diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 896a5b666ec..6653fd242fc 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -7,15 +7,7 @@ local globals = require("nvim-tree.globals")
 
 local Class = require("nvim-tree.classic")
 
----@class OpenInWinOpts
----@field hijack_current_buf boolean|nil default true
----@field resize boolean|nil default true
----@field winid number|nil 0 or nil for current
-
-local DEFAULT_MIN_WIDTH = 30
-local DEFAULT_MAX_WIDTH = -1
-local DEFAULT_PADDING = 1
-
+---Window and buffer related settings and operations
 ---@class (exact) View: Class
 ---@field live_filter table
 ---@field side string
@@ -101,6 +93,7 @@ local BUFFER_OPTIONS = {
   { name = "swapfile",   value = false },
 }
 
+-- TODO multi-instance remove this; delete buffers rather than retaining them
 ---@private
 ---@param bufnr integer
 ---@return boolean
@@ -113,6 +106,7 @@ function View:matches_bufnr(bufnr)
   return false
 end
 
+-- TODO multi-instance remove this; delete buffers rather than retaining them
 ---@private
 function View:wipe_rogue_buffer()
   for _, bufnr in ipairs(vim.api.nvim_list_bufs()) do
@@ -128,13 +122,12 @@ function View:create_buffer(bufnr)
   self:wipe_rogue_buffer()
 
   local tab = vim.api.nvim_get_current_tabpage()
-  globals.BUFNR_PER_TAB[tab] = bufnr or vim.api.nvim_create_buf(false, false)
 
-  if self.explorer.opts.experimental.multi_instance then
-    self.bufnr_by_tab[tab] = globals.BUFNR_PER_TAB[tab]
-  end
+  bufnr = bufnr or vim.api.nvim_create_buf(false, false)
 
-  bufnr = self:get_bufnr("View:create_buffer")
+  -- set both bufnr registries
+  globals.BUFNR_PER_TAB[tab] = bufnr
+  self.bufnr_by_tab[tab] = bufnr
 
   vim.api.nvim_buf_set_name(bufnr, "NvimTree_" .. tab)
 
@@ -481,6 +474,11 @@ function View:set_current_win(callsite)
   globals.TABPAGES[current_tab].winid = current_win
 end
 
+---@class OpenInWinOpts
+---@field hijack_current_buf boolean|nil default true
+---@field resize boolean|nil default true
+---@field winid number|nil 0 or nil for current
+
 ---Open the tree in the a window
 ---@param opts OpenInWinOpts|nil
 function View:open_in_win(opts)
@@ -510,13 +508,14 @@ function View:abandon_current_window()
       globals.BUFNR_PER_TAB[tab],
       self.bufnr_by_tab[tab],
       (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH")
-
-    self.bufnr_by_tab[tab] = nil
   end
 
-  -- TODO multi-instance kill the buffer instead of retaining
+  -- TODO multi-instance maybe kill the buffer instead of retaining
 
+  -- reset both bufnr registries
   globals.BUFNR_PER_TAB[tab] = nil
+  self.bufnr_by_tab[tab] = nil
+
   if globals.TABPAGES[tab] then
     globals.TABPAGES[tab].winid = nil
   end
@@ -614,6 +613,8 @@ function View:restore_tab_state()
   self:set_cursor(globals.CURSORS[tabpage])
 end
 
+--- TODO multi-instance remove comment
+--- not legacy codepath
 --- winid containing the buffer
 ---@param tabpage number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
 ---@param callsite string
@@ -689,7 +690,7 @@ end
 function View:get_bufnr(callsite)
   local tab = vim.api.nvim_get_current_tabpage()
   if self.explorer.opts.experimental.multi_instance then
-    local msg = string.format("View:get_bufnr(%-20.20s) globals.BUFNR_PER_TAB[%s]=b%s view.bufnr_by_tab[%s]=b%s MISMATCH",
+    local msg = string.format("View:get_bufnr(%-20.20s) globals.BUFNR_PER_TAB[%s]=b%s view.bufnr_by_tab[%s]=b%s %s",
       callsite,
       tab, globals.BUFNR_PER_TAB[tab],
       tab, self.bufnr_by_tab[tab],
@@ -765,7 +766,7 @@ end
 
 -- used on ColorScheme event
 function View:reset_winhl()
-  local winid = self:get_winid(nil, "View:reset_winhl1")
+  local winid = self:get_winid(nil, "View:reset_winhl")
   if winid and vim.api.nvim_win_is_valid(winid) then
     vim.wo[winid].winhl = appearance.WIN_HL
   end
@@ -777,6 +778,10 @@ function View:is_width_determined()
   return type(self.width) ~= "function"
 end
 
+local DEFAULT_MIN_WIDTH = 30
+local DEFAULT_MAX_WIDTH = -1
+local DEFAULT_PADDING = 1
+
 ---Configure width-related config
 ---@param width string|function|number|table|nil
 function View:configure_width(width)

From 414e576bc2c710729a2751bfc4c38bf2ac15b8f6 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 09:03:19 +1000
Subject: [PATCH 05/17] refactor(#2826): remove unnecessary view members float,
 hide_root_folder; use explorer opts

---
 lua/nvim-tree/actions/fs/remove-file.lua |  6 +++---
 lua/nvim-tree/actions/node/open-file.lua |  2 +-
 lua/nvim-tree/explorer/live-filter.lua   |  4 ++--
 lua/nvim-tree/explorer/view.lua          | 18 +++++++-----------
 4 files changed, 13 insertions(+), 17 deletions(-)

diff --git a/lua/nvim-tree/actions/fs/remove-file.lua b/lua/nvim-tree/actions/fs/remove-file.lua
index fd71ae6a376..ba1325f74ef 100644
--- a/lua/nvim-tree/actions/fs/remove-file.lua
+++ b/lua/nvim-tree/actions/fs/remove-file.lua
@@ -18,7 +18,7 @@ local function close_windows(windows)
   -- Prevent from closing when the win count equals 1 or 2,
   -- where the win to remove could be the last opened.
   -- For details see #2503.
-  if explorer and explorer.view.float.enable and #vim.api.nvim_list_wins() < 3 then
+  if explorer and explorer.opts.view.float.enable and #vim.api.nvim_list_wins() < 3 then
     return
   end
 
@@ -36,12 +36,12 @@ local function clear_buffer(absolute_path)
   for _, buf in pairs(bufs) do
     if buf.name == absolute_path then
       local tree_winnr = vim.api.nvim_get_current_win()
-      if buf.hidden == 0 and (#bufs > 1 or explorer and explorer.view.float.enable) then
+      if buf.hidden == 0 and (#bufs > 1 or explorer and explorer.opts.view.float.enable) then
         vim.api.nvim_set_current_win(buf.windows[1])
         vim.cmd(":bn")
       end
       vim.api.nvim_buf_delete(buf.bufnr, { force = true })
-      if explorer and not explorer.view.float.quit_on_focus_loss then
+      if explorer and not explorer.opts.view.float.quit_on_focus_loss then
         vim.api.nvim_set_current_win(tree_winnr)
       end
       if M.config.actions.remove_file.close_window then
diff --git a/lua/nvim-tree/actions/node/open-file.lua b/lua/nvim-tree/actions/node/open-file.lua
index b3bcce75a5a..b44870946d6 100644
--- a/lua/nvim-tree/actions/node/open-file.lua
+++ b/lua/nvim-tree/actions/node/open-file.lua
@@ -346,7 +346,7 @@ local function open_in_new_window(filename, mode)
     end
   end
 
-  if (mode == "preview" or mode == "preview_no_picker") and explorer and explorer.view.float.enable then
+  if (mode == "preview" or mode == "preview_no_picker") and explorer and explorer.opts.view.float.enable then
     -- ignore "WinLeave" autocmd on preview
     -- because the registered "WinLeave"
     -- will kill the floating window immediately
diff --git a/lua/nvim-tree/explorer/live-filter.lua b/lua/nvim-tree/explorer/live-filter.lua
index 9bd24406964..fbc643311e7 100644
--- a/lua/nvim-tree/explorer/live-filter.lua
+++ b/lua/nvim-tree/explorer/live-filter.lua
@@ -61,7 +61,7 @@ local overlay_bufnr = 0
 local overlay_winnr = 0
 
 local function remove_overlay(self)
-  if self.explorer.view.float.enable and self.explorer.view.float.quit_on_focus_loss then
+  if self.explorer.opts.view.float.enable and self.explorer.opts.view.float.quit_on_focus_loss then
     -- return to normal nvim-tree float behaviour when filter window is closed
     vim.api.nvim_create_autocmd("WinLeave", {
       pattern = "NvimTree_*",
@@ -171,7 +171,7 @@ local function calculate_overlay_win_width(self)
 end
 
 local function create_overlay(self)
-  if self.explorer.view.float.enable then
+  if self.explorer.opts.view.float.enable then
     -- don't close nvim-tree float when focus is changed to filter window
     vim.api.nvim_clear_autocmds({
       event   = "WinLeave",
diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 6653fd242fc..658deb8bf55 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -11,11 +11,9 @@ local Class = require("nvim-tree.classic")
 ---@class (exact) View: Class
 ---@field live_filter table
 ---@field side string
----@field float table
 ---@field private explorer Explorer
 ---@field private adaptive_size boolean
 ---@field private centralize_selection boolean
----@field private hide_root_folder boolean
 ---@field private winopts table
 ---@field private height integer
 ---@field private preserve_window_proportions boolean
@@ -40,9 +38,7 @@ function View:new(args)
   self.explorer                    = args.explorer
   self.adaptive_size               = false
   self.centralize_selection        = self.explorer.opts.view.centralize_selection
-  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
   self.preserve_window_proportions = self.explorer.opts.view.preserve_window_proportions
   self.side                        = (self.explorer.opts.view.side == "right") and "right" or "left"
   self.live_filter                 = { prev_focused_node = nil, }
@@ -217,16 +213,16 @@ end
 ---@private
 ---@return table
 function View:open_win_config()
-  if type(self.float.open_win_config) == "function" then
-    return self.float.open_win_config()
+  if type(self.explorer.opts.view.float.open_win_config) == "function" then
+    return self.explorer.opts.view.float.open_win_config()
   else
-    return self.float.open_win_config
+    return self.explorer.opts.view.float.open_win_config
   end
 end
 
 ---@private
 function View:open_window()
-  if self.float.enable then
+  if self.explorer.opts.view.float.enable then
     vim.api.nvim_open_win(0, true, self:open_win_config())
   else
     vim.api.nvim_command("vsp")
@@ -405,9 +401,9 @@ end
 
 ---@param size string|number|nil
 function View:resize(size)
-  if self.float.enable and not self.adaptive_size then
+  if self.explorer.opts.view.float.enable and not self.adaptive_size then
     -- if the floating windows's adaptive size is not desired, then the
-    -- float size should be defined in view.float.open_win_config
+    -- float size should be defined in self.explorer.opts.view.float.open_win_config
     return
   end
 
@@ -761,7 +757,7 @@ end
 ---@param cwd string|nil
 ---@return boolean
 function View:is_root_folder_visible(cwd)
-  return cwd ~= "/" and not self.hide_root_folder
+  return cwd ~= "/" and self.explorer.opts.renderer.root_folder_label ~= false
 end
 
 -- used on ColorScheme event

From f1e9d5165cfabfaa98553f3c19eff7a6851a0972 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 09:12:29 +1000
Subject: [PATCH 06/17] refactor(#2826): remove unused view members
 centralize_selection and preserve_window_proportions

---
 lua/nvim-tree/explorer/view.lua | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 658deb8bf55..305aead7786 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -13,10 +13,8 @@ local Class = require("nvim-tree.classic")
 ---@field side string
 ---@field private explorer Explorer
 ---@field private adaptive_size boolean
----@field private centralize_selection boolean
 ---@field private winopts table
 ---@field private height integer
----@field private preserve_window_proportions boolean
 ---@field private initial_width integer
 ---@field private width (fun():integer)|integer|string
 ---@field private max_width integer
@@ -37,9 +35,7 @@ function View:new(args)
 
   self.explorer                    = args.explorer
   self.adaptive_size               = false
-  self.centralize_selection        = self.explorer.opts.view.centralize_selection
   self.height                      = self.explorer.opts.view.height
-  self.preserve_window_proportions = self.explorer.opts.view.preserve_window_proportions
   self.side                        = (self.explorer.opts.view.side == "right") and "right" or "left"
   self.live_filter                 = { prev_focused_node = nil, }
   self.bufnr_by_tab                = {}
@@ -436,7 +432,7 @@ function View:resize(size)
 
   if new_size ~= vim.api.nvim_win_get_width(winid) then
     vim.api.nvim_win_set_width(winid, new_size)
-    if not self.preserve_window_proportions then
+    if not self.explorer.opts.view.preserve_window_proportions then
       vim.cmd(":wincmd =")
     end
   end

From 5fbd6745ebecc5cb7d649488009108bfa2c5d3ab Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 09:19:33 +1000
Subject: [PATCH 07/17] refactor(#2826): remove unused view member height

---
 lua/nvim-tree/explorer/view.lua | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 305aead7786..bbc43894460 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -14,7 +14,6 @@ local Class = require("nvim-tree.classic")
 ---@field private explorer Explorer
 ---@field private adaptive_size boolean
 ---@field private winopts table
----@field private height integer
 ---@field private initial_width integer
 ---@field private width (fun():integer)|integer|string
 ---@field private max_width integer
@@ -35,7 +34,6 @@ function View:new(args)
 
   self.explorer                    = args.explorer
   self.adaptive_size               = false
-  self.height                      = self.explorer.opts.view.height
   self.side                        = (self.explorer.opts.view.side == "right") and "right" or "left"
   self.live_filter                 = { prev_focused_node = nil, }
   self.bufnr_by_tab                = {}
@@ -419,7 +417,6 @@ function View:resize(size)
 
   if size then
     self.width = size
-    self.height = size
   end
 
   if not self:is_visible() then
@@ -770,6 +767,7 @@ function View:is_width_determined()
   return type(self.width) ~= "function"
 end
 
+-- These are needed as they are populated only by the user, not configuration
 local DEFAULT_MIN_WIDTH = 30
 local DEFAULT_MAX_WIDTH = -1
 local DEFAULT_PADDING = 1

From 3615c7dffe88116ef19071eafe36b5cd8a38621e Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 09:33:07 +1000
Subject: [PATCH 08/17] refactor(#2826): temporarily reuse BUFNR_PER_TAB in
 view constructor

---
 lua/nvim-tree/explorer/view.lua | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index bbc43894460..ae6cbe08f94 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -32,13 +32,13 @@ local View = Class:extend()
 function View:new(args)
   args.explorer:log_new("View")
 
-  self.explorer                    = args.explorer
-  self.adaptive_size               = false
-  self.side                        = (self.explorer.opts.view.side == "right") and "right" or "left"
-  self.live_filter                 = { prev_focused_node = nil, }
-  self.bufnr_by_tab                = {}
+  self.explorer      = args.explorer
+  self.adaptive_size = false
+  self.side          = (self.explorer.opts.view.side == "right") and "right" or "left"
+  self.live_filter   = { prev_focused_node = nil, }
+  self.bufnr_by_tab  = {}
 
-  self.winopts                     = {
+  self.winopts       = {
     relativenumber = self.explorer.opts.view.relativenumber,
     number         = self.explorer.opts.view.number,
     list           = false,
@@ -59,6 +59,10 @@ function View:new(args)
 
   self:configure_width(self.explorer.opts.view.width)
   self.initial_width = self:get_width()
+
+  -- TODO multi-instance remove this; delete buffers rather than retaining them
+  local tabid = vim.api.nvim_get_current_tabpage()
+  self.bufnr_by_tab[tabid] = globals.BUFNR_PER_TAB[tabid]
 end
 
 function View:destroy()

From 09ec00c085fac6da36f44a997ead03394e9e97c2 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 10:01:12 +1000
Subject: [PATCH 09/17] refactor(#2826): get_winid returns new after
 consistency check

---
 lua/nvim-tree/explorer/view.lua | 12 ++++++++----
 lua/nvim-tree/lib.lua           |  1 +
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index ae6cbe08f94..8f1ce3d39b7 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -539,6 +539,7 @@ end
 ---@param opts table|nil
 ---@return boolean
 function View:is_visible(opts)
+  -- TODO multi-instance rewrite and consistency check
   if opts and opts.tabpage then
     if globals.TABPAGES[opts.tabpage] == nil then
       return false
@@ -618,10 +619,10 @@ function View:winid(tabpage, callsite)
   local msg = string.format("View:winid(%3s, %-20.20s)", tabpage, callsite)
 
   if bufnr then
-    for _, w in pairs(vim.api.nvim_tabpage_list_wins(tabpage or 0)) do
-      if vim.api.nvim_win_get_buf(w) == bufnr then
-        log.line("dev", "%s b%d : w%s", msg, bufnr, w)
-        return w
+    for _, winid in pairs(vim.api.nvim_tabpage_list_wins(tabpage or 0)) do
+      if vim.api.nvim_win_get_buf(winid) == bufnr then
+        log.line("dev", "%s b%d : w%s", msg, bufnr, winid)
+        return winid
       end
     end
   else
@@ -669,6 +670,8 @@ function View:get_winid(tabpage, callsite)
     if winid ~= tabinfo_winid then
       notify.error(msg)
     end
+
+    return winid
   end
 
   -- legacy codepath
@@ -712,6 +715,7 @@ function View:prevent_buffer_override()
     local curbuf = vim.api.nvim_win_get_buf(curwin)
     local bufname = vim.api.nvim_buf_get_name(curbuf)
 
+    --- TODO multi-instance this can be removed as winid() will handle it
     if not bufname:match("NvimTree") then
       for i, tabpage in ipairs(globals.TABPAGES) do
         if tabpage.winid == view_winid then
diff --git a/lua/nvim-tree/lib.lua b/lua/nvim-tree/lib.lua
index cd6442cc044..854e33bfd09 100644
--- a/lua/nvim-tree/lib.lua
+++ b/lua/nvim-tree/lib.lua
@@ -135,6 +135,7 @@ function M.open(opts)
     open_view_and_draw()
   end
 
+  -- TODO multi-instance is this actually necessary?
   if explorer then
     explorer.view:restore_tab_state()
   end

From 83fdff7c4a84950d6f3ec3cdcbbeb57e51b9bd0a Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 11:18:38 +1000
Subject: [PATCH 10/17] refactor(#2826): globals.TABPAGES -> WINID_PER_TAB

---
 lua/nvim-tree.lua                      |   2 +-
 lua/nvim-tree/explorer/view.lua        | 127 ++++++-------------------
 lua/nvim-tree/globals.lua              |   2 +-
 lua/nvim-tree/multi-instance-debug.lua |  10 +-
 4 files changed, 36 insertions(+), 105 deletions(-)

diff --git a/lua/nvim-tree.lua b/lua/nvim-tree.lua
index 45087633f9f..78a27a7a696 100644
--- a/lua/nvim-tree.lua
+++ b/lua/nvim-tree.lua
@@ -668,7 +668,7 @@ function M.purge_all_state()
   local explorer = core.get_explorer()
   if explorer then
     explorer.view:close_all_tabs()
-    explorer.view:abandon_all_windows("purge_all_state")
+    explorer.view:abandon_all_windows()
     require("nvim-tree.git").purge_state()
     explorer:destroy()
     core.reset_explorer()
diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 8f1ce3d39b7..a54b4f2e4c0 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -69,14 +69,6 @@ function View:destroy()
   self.explorer:log_destroy("View")
 end
 
--- The initial state of a tab
-local tabinitial = {
-  -- The position of the cursor { line, column }
-  cursor = { 0, 0 },
-  -- The NvimTree window number
-  winid = nil,
-}
-
 ---@type { name: string, value: any }[]
 local BUFFER_OPTIONS = {
   { name = "bufhidden",  value = "wipe" },
@@ -163,24 +155,6 @@ local move_tbl = {
   right = "L",
 }
 
--- setup_tabpage sets up the initial state of a tab
----@private
----@param tabpage integer
----@param callsite string
-function View:setup_tabpage(tabpage, callsite)
-  local winid = vim.api.nvim_get_current_win()
-
-  if self.explorer.opts.experimental.multi_instance then
-    log.line("dev", "View:setup_tabpage(%3s, %-20.20s) w%d %s",
-      tabpage,
-      callsite,
-      winid,
-      globals.TABPAGES[tabpage] and vim.inspect(globals.TABPAGES[tabpage], { newline = "" }) or "tabinitial")
-  end
-
-  globals.TABPAGES[tabpage] = vim.tbl_extend("force", globals.TABPAGES[tabpage] or tabinitial, { winid = winid })
-end
-
 ---@private
 function View:set_window_options_and_buffer()
   pcall(vim.api.nvim_command, "buffer " .. self:get_bufnr("View:set_window_options_and_buffer"))
@@ -226,7 +200,7 @@ function View:open_window()
     vim.api.nvim_command("vsp")
     self:reposition_window()
   end
-  self:setup_tabpage(vim.api.nvim_get_current_tabpage(), "View:open_window")
+  globals.WINID_PER_TAB[vim.api.nvim_get_current_tabpage()] = vim.api.nvim_get_current_win()
   self:set_window_options_and_buffer()
 end
 
@@ -308,7 +282,7 @@ function View:close_this_tab_only()
 end
 
 function View:close_all_tabs()
-  for tabpage, _ in pairs(globals.TABPAGES) do
+  for tabpage, _ in pairs(globals.WINID_PER_TAB) do
     self:close_internal(tabpage)
   end
 end
@@ -449,22 +423,9 @@ function View:reposition_window()
 end
 
 ---@private
----@param callsite string
-function View:set_current_win(callsite)
+function View:set_current_win()
   local current_tab = vim.api.nvim_get_current_tabpage()
-  local current_win = vim.api.nvim_get_current_win()
-
-  if self.explorer.opts.experimental.multi_instance then
-    log.line("dev", "View:set_current_win(%-20.20s) t%d w%3s->w%3s %s",
-      callsite,
-      current_tab,
-      globals.TABPAGES[current_tab].winid,
-      current_win,
-      (globals.TABPAGES[current_tab].winid == current_win) and "" or "MISMATCH"
-    )
-  end
-
-  globals.TABPAGES[current_tab].winid = current_win
+  globals.WINID_PER_TAB[current_tab] = vim.api.nvim_get_current_win()
 end
 
 ---@class OpenInWinOpts
@@ -481,8 +442,8 @@ function View: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:open_in_win")
-  self:set_current_win("View:open_in_win")
+  globals.WINID_PER_TAB[vim.api.nvim_get_current_tabpage()] = vim.api.nvim_get_current_win()
+  self:set_current_win()
   self:set_window_options_and_buffer()
   if opts.resize then
     self:reposition_window()
@@ -497,7 +458,7 @@ function View:abandon_current_window()
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:abandon_current_window() t%d w%s b%s member b%s %s",
       tab,
-      globals.TABPAGES[tab] and globals.TABPAGES[tab].winid or nil,
+      globals.WINID_PER_TAB[tab],
       globals.BUFNR_PER_TAB[tab],
       self.bufnr_by_tab[tab],
       (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH")
@@ -509,30 +470,14 @@ function View:abandon_current_window()
   globals.BUFNR_PER_TAB[tab] = nil
   self.bufnr_by_tab[tab] = nil
 
-  if globals.TABPAGES[tab] then
-    globals.TABPAGES[tab].winid = nil
-  end
+  globals.WINID_PER_TAB[tab] = nil
 end
 
----@param callsite string
-function View:abandon_all_windows(callsite)
+function View:abandon_all_windows()
+  -- TODO multi-instance kill the buffer instead of retaining
   for tab, _ in pairs(vim.api.nvim_list_tabpages()) do
-    if self.explorer.opts.experimental.multi_instance then
-      log.line("dev", "View:abandon_all_windows(%-20.20s) t%d w%s b%s member b%s %s",
-        callsite,
-        tab,
-        globals.TABPAGES and globals.TABPAGES.winid or nil,
-        globals.BUFNR_PER_TAB[tab],
-        self.bufnr_by_tab[tab],
-        (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH")
-    end
-
-    -- TODO multi-instance kill the buffer instead of retaining
-
     globals.BUFNR_PER_TAB[tab] = nil
-    if globals.TABPAGES[tab] then
-      globals.TABPAGES[tab].winid = nil
-    end
+    globals.WINID_PER_TAB[tab] = nil
   end
 end
 
@@ -541,16 +486,16 @@ end
 function View:is_visible(opts)
   -- TODO multi-instance rewrite and consistency check
   if opts and opts.tabpage then
-    if globals.TABPAGES[opts.tabpage] == nil then
+    if not globals.WINID_PER_TAB[opts.tabpage] then
       return false
     end
-    local winid = globals.TABPAGES[opts.tabpage].winid
+    local winid = globals.WINID_PER_TAB[opts.tabpage]
     return winid and vim.api.nvim_win_is_valid(winid)
   end
 
   if opts and opts.any_tabpage then
-    for _, v in pairs(globals.TABPAGES) do
-      if v.winid and vim.api.nvim_win_is_valid(v.winid) then
+    for _, winid in pairs(globals.WINID_PER_TAB) do
+      if winid and vim.api.nvim_win_is_valid(winid) then
         return true
       end
     end
@@ -611,22 +556,16 @@ end
 --- not legacy codepath
 --- winid containing the buffer
 ---@param tabpage number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
----@param callsite string
 ---@return integer? winid
-function View:winid(tabpage, callsite)
+function View:winid(tabpage)
   local bufnr = self.bufnr_by_tab[tabpage]
 
-  local msg = string.format("View:winid(%3s, %-20.20s)", tabpage, callsite)
-
   if bufnr then
     for _, winid in pairs(vim.api.nvim_tabpage_list_wins(tabpage or 0)) do
       if vim.api.nvim_win_get_buf(winid) == bufnr then
-        log.line("dev", "%s b%d : w%s", msg, bufnr, winid)
         return winid
       end
     end
-  else
-    log.line("dev", "%s no bufnr", msg)
   end
 end
 
@@ -636,28 +575,26 @@ end
 ---@return number|nil
 function View:get_winid(tabpage, callsite)
   local tabid = tabpage or vim.api.nvim_get_current_tabpage()
-  local tabinfo = globals.TABPAGES[tabid]
   local tabinfo_winid = nil
 
   if self.explorer.opts.experimental.multi_instance then
+
     local msg_fault = ""
-    if not tabinfo then
-      msg_fault = "no tabinfo"
-    elseif not tabinfo.winid then
-      msg_fault = "no tabinfo.winid"
-    elseif not vim.api.nvim_win_is_valid(tabinfo.winid) then
-      msg_fault = string.format("invalid tabinfo.winid %d", tabinfo.winid)
+    if not globals.WINID_PER_TAB[tabid] then
+      msg_fault = "no WINID_PER_TAB"
+    elseif not vim.api.nvim_win_is_valid(globals.WINID_PER_TAB[tabid]) then
+      msg_fault = string.format("invalid globals.WINID_PER_TAB[tabid] %d", globals.WINID_PER_TAB[tabid])
     else
-      tabinfo_winid = tabinfo.winid
+      tabinfo_winid = globals.WINID_PER_TAB[tabid]
     end
 
-    local winid = self:winid(tabid, "View:get_winid")
+    local winid = self:winid(tabid)
 
     if winid ~= tabinfo_winid then
       msg_fault = "MISMATCH"
     end
 
-    local msg = string.format("View:get_winid(%3s, %-20.20s) globals.TABPAGES[%s].winid=w%s view.winid(%s)=w%s %s",
+    local msg = string.format("View:get_winid(%3s, %-20.20s) globals.TABPAGES[%s]=w%s view.winid(%s)=w%s %s",
       tabpage,
       callsite,
       tabid, tabinfo_winid,
@@ -670,13 +607,11 @@ function View:get_winid(tabpage, callsite)
     if winid ~= tabinfo_winid then
       notify.error(msg)
     end
-
-    return winid
   end
 
   -- legacy codepath
-  if tabinfo and tabinfo.winid and vim.api.nvim_win_is_valid(tabinfo.winid) then
-    return tabinfo.winid
+  if tabinfo_winid and vim.api.nvim_win_is_valid(tabinfo_winid) then
+    return tabinfo_winid
   end
 end
 
@@ -717,13 +652,9 @@ function View:prevent_buffer_override()
 
     --- TODO multi-instance this can be removed as winid() will handle it
     if not bufname:match("NvimTree") then
-      for i, tabpage in ipairs(globals.TABPAGES) do
-        if tabpage.winid == view_winid then
-          if self.explorer.opts.experimental.multi_instance then
-            log.line("dev", "View:prevent_buffer_override() t%d w%d clearing", i, view_winid)
-          end
-
-          globals.TABPAGES[i] = nil
+      for i, winid in ipairs(globals.WINID_PER_TAB) do
+        if winid == view_winid then
+          globals.WINID_PER_TAB[i] = nil
           break
         end
       end
diff --git a/lua/nvim-tree/globals.lua b/lua/nvim-tree/globals.lua
index 58e3452f7ee..00c857767b3 100644
--- a/lua/nvim-tree/globals.lua
+++ b/lua/nvim-tree/globals.lua
@@ -2,7 +2,7 @@
 
 local M = {
   -- from View
-  TABPAGES = {},
+  WINID_PER_TAB = {},
   BUFNR_PER_TAB = {},
   CURSORS = {},
 }
diff --git a/lua/nvim-tree/multi-instance-debug.lua b/lua/nvim-tree/multi-instance-debug.lua
index d33f34a1313..d76c0b565ea 100644
--- a/lua/nvim-tree/multi-instance-debug.lua
+++ b/lua/nvim-tree/multi-instance-debug.lua
@@ -3,7 +3,7 @@ local globals = require("nvim-tree.globals")
 local M = {}
 
 --- Debugging only.
---- Tabs show TABPAGES winid and BUFNR_PER_TAB bufnr for the tab.
+--- Tabs show WINID_PER_TAB winid and BUFNR_PER_TAB bufnr for the tab.
 --- Orphans for inexistent tab_ids are shown at the right.
 --- lib.target_winid is always shown at the right next to a close button.
 --- Enable with:
@@ -15,7 +15,7 @@ function M.tab_line()
   local cur_tab_id = vim.api.nvim_get_current_tabpage()
 
   local bufnr_per_tab = vim.deepcopy(globals.BUFNR_PER_TAB)
-  local tabpages = vim.deepcopy(globals.TABPAGES)
+  local tabpages = vim.deepcopy(globals.WINID_PER_TAB)
 
   local tl = "%#TabLine#"
 
@@ -34,9 +34,9 @@ function M.tab_line()
     tl = tl .. " t" .. tab_id
 
     -- winid, if present
-    local tp = globals.TABPAGES[tab_id]
+    local tp = globals.WINID_PER_TAB[tab_id]
     if tp then
-      tl = tl .. " w" .. (tp.winid or "nil")
+      tl = tl .. " w" .. (tp or "nil")
     else
       tl = tl .. "      "
     end
@@ -67,7 +67,7 @@ function M.tab_line()
   end
   for tab_id, tp in pairs(tabpages) do
     orphans[tab_id] = orphans[tab_id] or {}
-    orphans[tab_id].winid = tp.winid
+    orphans[tab_id].winid = tp
   end
 
   -- right-align

From e875f15b327a9a63f9b37fb12e177d403be8c14b Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 12:01:24 +1000
Subject: [PATCH 11/17] refactor(#2826): consistent naming of tabid

---
 lua/nvim-tree/explorer/view.lua        | 139 +++++++++++++------------
 lua/nvim-tree/globals.lua              |   4 +-
 lua/nvim-tree/multi-instance-debug.lua |  28 ++---
 3 files changed, 89 insertions(+), 82 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index a54b4f2e4c0..e879b594c5a 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -18,7 +18,7 @@ local Class = require("nvim-tree.classic")
 ---@field private width (fun():integer)|integer|string
 ---@field private max_width integer
 ---@field private padding integer
----@field private bufnr_by_tab table<integer, integer> stored per tab until multi-instance is complete
+---@field private bufnr_by_tabid table<integer, integer> stored per tab until multi-instance is complete
 local View = Class:extend()
 
 ---@class View
@@ -36,7 +36,7 @@ function View:new(args)
   self.adaptive_size = false
   self.side          = (self.explorer.opts.view.side == "right") and "right" or "left"
   self.live_filter   = { prev_focused_node = nil, }
-  self.bufnr_by_tab  = {}
+  self.bufnr_by_tabid  = {}
 
   self.winopts       = {
     relativenumber = self.explorer.opts.view.relativenumber,
@@ -62,7 +62,7 @@ function View:new(args)
 
   -- TODO multi-instance remove this; delete buffers rather than retaining them
   local tabid = vim.api.nvim_get_current_tabpage()
-  self.bufnr_by_tab[tabid] = globals.BUFNR_PER_TAB[tabid]
+  self.bufnr_by_tabid[tabid] = globals.BUFNR_BY_TABID[tabid]
 end
 
 function View:destroy()
@@ -84,7 +84,7 @@ local BUFFER_OPTIONS = {
 ---@param bufnr integer
 ---@return boolean
 function View:matches_bufnr(bufnr)
-  for _, b in pairs(globals.BUFNR_PER_TAB) do
+  for _, b in pairs(globals.BUFNR_BY_TABID) do
     if b == bufnr then
       return true
     end
@@ -107,15 +107,15 @@ end
 function View:create_buffer(bufnr)
   self:wipe_rogue_buffer()
 
-  local tab = vim.api.nvim_get_current_tabpage()
+  local tabid = vim.api.nvim_get_current_tabpage()
 
   bufnr = bufnr or vim.api.nvim_create_buf(false, false)
 
   -- set both bufnr registries
-  globals.BUFNR_PER_TAB[tab] = bufnr
-  self.bufnr_by_tab[tab] = bufnr
+  globals.BUFNR_BY_TABID[tabid] = bufnr
+  self.bufnr_by_tabid[tabid] = bufnr
 
-  vim.api.nvim_buf_set_name(bufnr, "NvimTree_" .. tab)
+  vim.api.nvim_buf_set_name(bufnr, "NvimTree_" .. tabid)
 
   for _, option in ipairs(BUFFER_OPTIONS) do
     vim.api.nvim_set_option_value(option.name, option.value, { buf = bufnr })
@@ -200,7 +200,7 @@ function View:open_window()
     vim.api.nvim_command("vsp")
     self:reposition_window()
   end
-  globals.WINID_PER_TAB[vim.api.nvim_get_current_tabpage()] = vim.api.nvim_get_current_win()
+  globals.WINID_BY_TABID[vim.api.nvim_get_current_tabpage()] = vim.api.nvim_get_current_win()
   self:set_window_options_and_buffer()
 end
 
@@ -237,26 +237,26 @@ end
 
 ---save_tab_state saves any state that should be preserved across redraws.
 ---@private
----@param tabnr integer
-function View:save_tab_state(tabnr)
-  local tabpage = tabnr or vim.api.nvim_get_current_tabpage()
-  globals.CURSORS[tabpage] = vim.api.nvim_win_get_cursor(self:get_winid(tabpage, "View:save_tab_state") or 0)
+---@param tabid integer
+function View:save_tab_state(tabid)
+  tabid = tabid or vim.api.nvim_get_current_tabpage()
+  globals.CURSORS[tabid] = vim.api.nvim_win_get_cursor(self:get_winid(tabid, "View:save_tab_state") or 0)
 end
 
 ---@private
----@param tabpage integer
-function View:close_internal(tabpage)
+---@param tabid integer
+function View:close_internal(tabid)
   if self.explorer.opts.experimental.multi_instance then
-    log.line("dev", "View:close_internal(t%s)", tabpage)
+    log.line("dev", "View:close_internal(t%s)", tabid)
   end
-  if not self:is_visible({ tabpage = tabpage }) then
+  if not self:is_visible({ tabpage = tabid }) then
     return
   end
-  self:save_tab_state(tabpage)
+  self:save_tab_state(tabid)
   switch_buf_if_last_buf()
-  local tree_win = self:get_winid(tabpage, "View:close_internal")
+  local tree_win = self:get_winid(tabid, "View:close_internal")
   local current_win = vim.api.nvim_get_current_win()
-  for _, win in pairs(vim.api.nvim_tabpage_list_wins(tabpage)) do
+  for _, win in pairs(vim.api.nvim_tabpage_list_wins(tabid)) do
     if vim.api.nvim_win_get_config(win).relative == "" then
       local prev_win = vim.fn.winnr("#") -- this tab only
       if tree_win == current_win and prev_win > 0 then
@@ -264,7 +264,7 @@ function View:close_internal(tabpage)
       end
       if vim.api.nvim_win_is_valid(tree_win or 0) then
         if self.explorer.opts.experimental.multi_instance then
-          log.line("dev", "View:close_internal(t%s) w%s", tabpage, tree_win)
+          log.line("dev", "View:close_internal(t%s) w%s", tabid, tree_win)
         end
         local success, error = pcall(vim.api.nvim_win_close, tree_win or 0, true)
         if not success then
@@ -278,26 +278,34 @@ function View:close_internal(tabpage)
 end
 
 function View:close_this_tab_only()
+  if self.explorer.opts.experimental.multi_instance then
+    log.line("dev", "View:close_this_tab_only()")
+  end
   self:close_internal(vim.api.nvim_get_current_tabpage())
 end
 
+-- TODO this is broken at 1.13.0 - current tab does not close when tab.sync.close is set
 function View:close_all_tabs()
-  for tabpage, _ in pairs(globals.WINID_PER_TAB) do
-    self:close_internal(tabpage)
+  log.line("dev", "View:close_all_tabs() globals.WINID_BY_TABID=%s", vim.inspect(globals.WINID_BY_TABID))
+  for tabid, _ in pairs(globals.WINID_BY_TABID) do
+    if self.explorer.opts.experimental.multi_instance then
+      log.line("dev", "View:close_all_tabs()")
+    end
+    self:close_internal(tabid)
   end
 end
 
----@param tabpage integer|nil
+---@param tabid integer|nil
 ---@param callsite string
-function View:close(tabpage, callsite)
+function View:close(tabid, callsite)
   if self.explorer.opts.experimental.multi_instance then
-    log.line("dev", "View:close(t%s, %s)", tabpage, callsite)
+    log.line("dev", "View:close(t%s, %s)", tabid, callsite)
   end
 
   if self.explorer.opts.tab.sync.close then
     self:close_all_tabs()
-  elseif tabpage then
-    self:close_internal(tabpage)
+  elseif tabid then
+    self:close_internal(tabid)
   else
     self:close_this_tab_only()
   end
@@ -425,7 +433,7 @@ end
 ---@private
 function View:set_current_win()
   local current_tab = vim.api.nvim_get_current_tabpage()
-  globals.WINID_PER_TAB[current_tab] = vim.api.nvim_get_current_win()
+  globals.WINID_BY_TABID[current_tab] = vim.api.nvim_get_current_win()
 end
 
 ---@class OpenInWinOpts
@@ -442,7 +450,7 @@ function View: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())
-  globals.WINID_PER_TAB[vim.api.nvim_get_current_tabpage()] = vim.api.nvim_get_current_win()
+  globals.WINID_BY_TABID[vim.api.nvim_get_current_tabpage()] = vim.api.nvim_get_current_win()
   self:set_current_win()
   self:set_window_options_and_buffer()
   if opts.resize then
@@ -458,26 +466,26 @@ function View:abandon_current_window()
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:abandon_current_window() t%d w%s b%s member b%s %s",
       tab,
-      globals.WINID_PER_TAB[tab],
-      globals.BUFNR_PER_TAB[tab],
-      self.bufnr_by_tab[tab],
-      (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH")
+      globals.WINID_BY_TABID[tab],
+      globals.BUFNR_BY_TABID[tab],
+      self.bufnr_by_tabid[tab],
+      (globals.BUFNR_BY_TABID[tab] == self.bufnr_by_tabid[tab]) and "" or "MISMATCH")
   end
 
   -- TODO multi-instance maybe kill the buffer instead of retaining
 
   -- reset both bufnr registries
-  globals.BUFNR_PER_TAB[tab] = nil
-  self.bufnr_by_tab[tab] = nil
+  globals.BUFNR_BY_TABID[tab] = nil
+  self.bufnr_by_tabid[tab] = nil
 
-  globals.WINID_PER_TAB[tab] = nil
+  globals.WINID_BY_TABID[tab] = nil
 end
 
 function View:abandon_all_windows()
   -- TODO multi-instance kill the buffer instead of retaining
   for tab, _ in pairs(vim.api.nvim_list_tabpages()) do
-    globals.BUFNR_PER_TAB[tab] = nil
-    globals.WINID_PER_TAB[tab] = nil
+    globals.BUFNR_BY_TABID[tab] = nil
+    globals.WINID_BY_TABID[tab] = nil
   end
 end
 
@@ -486,15 +494,15 @@ end
 function View:is_visible(opts)
   -- TODO multi-instance rewrite and consistency check
   if opts and opts.tabpage then
-    if not globals.WINID_PER_TAB[opts.tabpage] then
+    if not globals.WINID_BY_TABID[opts.tabpage] then
       return false
     end
-    local winid = globals.WINID_PER_TAB[opts.tabpage]
+    local winid = globals.WINID_BY_TABID[opts.tabpage]
     return winid and vim.api.nvim_win_is_valid(winid)
   end
 
   if opts and opts.any_tabpage then
-    for _, winid in pairs(globals.WINID_PER_TAB) do
+    for _, winid in pairs(globals.WINID_BY_TABID) do
       if winid and vim.api.nvim_win_is_valid(winid) then
         return true
       end
@@ -548,20 +556,19 @@ end
 
 --- Restores the state of a NvimTree window if it was initialized before.
 function View:restore_tab_state()
-  local tabpage = vim.api.nvim_get_current_tabpage()
-  self:set_cursor(globals.CURSORS[tabpage])
+  self:set_cursor(globals.CURSORS[vim.api.nvim_get_current_tabpage()])
 end
 
 --- TODO multi-instance remove comment
 --- not legacy codepath
 --- winid containing the buffer
----@param tabpage number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
+---@param tabid number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
 ---@return integer? winid
-function View:winid(tabpage)
-  local bufnr = self.bufnr_by_tab[tabpage]
+function View:winid(tabid)
+  local bufnr = self.bufnr_by_tabid[tabid]
 
   if bufnr then
-    for _, winid in pairs(vim.api.nvim_tabpage_list_wins(tabpage or 0)) do
+    for _, winid in pairs(vim.api.nvim_tabpage_list_wins(tabid or 0)) do
       if vim.api.nvim_win_get_buf(winid) == bufnr then
         return winid
       end
@@ -570,22 +577,22 @@ function View:winid(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.
+---@param tabid number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
 ---@param callsite string
 ---@return number|nil
-function View:get_winid(tabpage, callsite)
-  local tabid = tabpage or vim.api.nvim_get_current_tabpage()
+function View:get_winid(tabid, callsite)
+  local tabid_param = tabid
+  tabid = tabid or vim.api.nvim_get_current_tabpage()
   local tabinfo_winid = nil
 
   if self.explorer.opts.experimental.multi_instance then
-
     local msg_fault = ""
-    if not globals.WINID_PER_TAB[tabid] then
-      msg_fault = "no WINID_PER_TAB"
-    elseif not vim.api.nvim_win_is_valid(globals.WINID_PER_TAB[tabid]) then
-      msg_fault = string.format("invalid globals.WINID_PER_TAB[tabid] %d", globals.WINID_PER_TAB[tabid])
+    if not globals.WINID_BY_TABID[tabid] then
+      msg_fault = "no WINID_BY_TABID"
+    elseif not vim.api.nvim_win_is_valid(globals.WINID_BY_TABID[tabid]) then
+      msg_fault = string.format("invalid globals.WINID_BY_TABID[tabid] %d", globals.WINID_BY_TABID[tabid])
     else
-      tabinfo_winid = globals.WINID_PER_TAB[tabid]
+      tabinfo_winid = globals.WINID_BY_TABID[tabid]
     end
 
     local winid = self:winid(tabid)
@@ -595,7 +602,7 @@ function View:get_winid(tabpage, callsite)
     end
 
     local msg = string.format("View:get_winid(%3s, %-20.20s) globals.TABPAGES[%s]=w%s view.winid(%s)=w%s %s",
-      tabpage,
+      tabid_param,
       callsite,
       tabid, tabinfo_winid,
       tabid, winid,
@@ -621,20 +628,20 @@ end
 function View:get_bufnr(callsite)
   local tab = vim.api.nvim_get_current_tabpage()
   if self.explorer.opts.experimental.multi_instance then
-    local msg = string.format("View:get_bufnr(%-20.20s) globals.BUFNR_PER_TAB[%s]=b%s view.bufnr_by_tab[%s]=b%s %s",
+    local msg = string.format("View:get_bufnr(%-20.20s) globals.BUFNR_BY_TABID[%s]=b%s view.bufnr_by_tab[%s]=b%s %s",
       callsite,
-      tab, globals.BUFNR_PER_TAB[tab],
-      tab, self.bufnr_by_tab[tab],
-      (globals.BUFNR_PER_TAB[tab] == self.bufnr_by_tab[tab]) and "" or "MISMATCH"
+      tab, globals.BUFNR_BY_TABID[tab],
+      tab, self.bufnr_by_tabid[tab],
+      (globals.BUFNR_BY_TABID[tab] == self.bufnr_by_tabid[tab]) and "" or "MISMATCH"
     )
 
-    if globals.BUFNR_PER_TAB[tab] ~= self.bufnr_by_tab[tab] then
+    if globals.BUFNR_BY_TABID[tab] ~= self.bufnr_by_tabid[tab] then
       notify.error(msg)
     end
 
     log.line("dev", msg)
   end
-  return globals.BUFNR_PER_TAB[tab]
+  return globals.BUFNR_BY_TABID[tab]
 end
 
 function View:prevent_buffer_override()
@@ -652,9 +659,9 @@ function View:prevent_buffer_override()
 
     --- TODO multi-instance this can be removed as winid() will handle it
     if not bufname:match("NvimTree") then
-      for i, winid in ipairs(globals.WINID_PER_TAB) do
+      for i, winid in ipairs(globals.WINID_BY_TABID) do
         if winid == view_winid then
-          globals.WINID_PER_TAB[i] = nil
+          globals.WINID_BY_TABID[i] = nil
           break
         end
       end
diff --git a/lua/nvim-tree/globals.lua b/lua/nvim-tree/globals.lua
index 00c857767b3..66211260bc6 100644
--- a/lua/nvim-tree/globals.lua
+++ b/lua/nvim-tree/globals.lua
@@ -2,8 +2,8 @@
 
 local M = {
   -- from View
-  WINID_PER_TAB = {},
-  BUFNR_PER_TAB = {},
+  WINID_BY_TABID = {},
+  BUFNR_BY_TABID = {},
   CURSORS = {},
 }
 
diff --git a/lua/nvim-tree/multi-instance-debug.lua b/lua/nvim-tree/multi-instance-debug.lua
index d76c0b565ea..0482d62f673 100644
--- a/lua/nvim-tree/multi-instance-debug.lua
+++ b/lua/nvim-tree/multi-instance-debug.lua
@@ -3,7 +3,7 @@ local globals = require("nvim-tree.globals")
 local M = {}
 
 --- Debugging only.
---- Tabs show WINID_PER_TAB winid and BUFNR_PER_TAB bufnr for the tab.
+--- Tabs show WINID_BY_TABID winid and BUFNR_BY_TABID bufnr for the tab.
 --- Orphans for inexistent tab_ids are shown at the right.
 --- lib.target_winid is always shown at the right next to a close button.
 --- Enable with:
@@ -11,30 +11,30 @@ local M = {}
 ---   vim.opt.showtabline = 2
 ---@return string
 function M.tab_line()
-  local tab_ids = vim.api.nvim_list_tabpages()
-  local cur_tab_id = vim.api.nvim_get_current_tabpage()
+  local tabids = vim.api.nvim_list_tabpages()
+  local tabid_cur = vim.api.nvim_get_current_tabpage()
 
-  local bufnr_per_tab = vim.deepcopy(globals.BUFNR_PER_TAB)
-  local tabpages = vim.deepcopy(globals.WINID_PER_TAB)
+  local bufnr_by_tabid = vim.deepcopy(globals.BUFNR_BY_TABID)
+  local winid_by_tabid = vim.deepcopy(globals.WINID_BY_TABID)
 
   local tl = "%#TabLine#"
 
-  for i, tab_id in ipairs(tab_ids) do
+  for i, tabid in ipairs(tabids) do
     -- click to select
     tl = tl .. "%" .. i .. "T"
 
     -- style
-    if tab_id == cur_tab_id then
+    if tabid == tabid_cur then
       tl = tl .. "%#StatusLine#|"
     else
       tl = tl .. "|%#TabLine#"
     end
 
     -- tab_id itself
-    tl = tl .. " t" .. tab_id
+    tl = tl .. " t" .. tabid
 
     -- winid, if present
-    local tp = globals.WINID_PER_TAB[tab_id]
+    local tp = globals.WINID_BY_TABID[tabid]
     if tp then
       tl = tl .. " w" .. (tp or "nil")
     else
@@ -42,7 +42,7 @@ function M.tab_line()
     end
 
     -- bufnr, if present
-    local bpt = globals.BUFNR_PER_TAB[tab_id]
+    local bpt = globals.BUFNR_BY_TABID[tabid]
     if bpt then
       tl = tl .. " b" .. bpt
     else
@@ -52,8 +52,8 @@ function M.tab_line()
     tl = tl .. " "
 
     -- remove actively mapped
-    bufnr_per_tab[tab_id] = nil
-    tabpages[tab_id] = nil
+    bufnr_by_tabid[tabid] = nil
+    winid_by_tabid[tabid] = nil
   end
 
   -- close last and reset
@@ -61,11 +61,11 @@ function M.tab_line()
 
   -- collect orphans
   local orphans = {}
-  for tab_id, bufnr in pairs(bufnr_per_tab) do
+  for tab_id, bufnr in pairs(bufnr_by_tabid) do
     orphans[tab_id] = orphans[tab_id] or {}
     orphans[tab_id].bufnr = bufnr
   end
-  for tab_id, tp in pairs(tabpages) do
+  for tab_id, tp in pairs(winid_by_tabid) do
     orphans[tab_id] = orphans[tab_id] or {}
     orphans[tab_id].winid = tp
   end

From d72f85f5244dc111d2a09edd329ef28b9a56d0ef Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 12:33:16 +1000
Subject: [PATCH 12/17] refactor(#2826): more consistency checking

---
 lua/nvim-tree/explorer/init.lua |   3 -
 lua/nvim-tree/explorer/view.lua | 117 ++++++++++++++++++++++++--------
 2 files changed, 87 insertions(+), 33 deletions(-)

diff --git a/lua/nvim-tree/explorer/init.lua b/lua/nvim-tree/explorer/init.lua
index 54b30c60057..6625d5b0870 100644
--- a/lua/nvim-tree/explorer/init.lua
+++ b/lua/nvim-tree/explorer/init.lua
@@ -85,9 +85,6 @@ function Explorer:destroy()
   self.sorters:destroy()
   self.view:destroy()
 
-  -- TODO existing buffer is retained by global and re-used. Delete it or retain it.
-  -- see wipe_rogue_buffer
-
   vim.api.nvim_del_augroup_by_id(self.augroup_id)
 
   RootNode.destroy(self)
diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index e879b594c5a..0cbdb899241 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -32,13 +32,13 @@ local View = Class:extend()
 function View:new(args)
   args.explorer:log_new("View")
 
-  self.explorer      = args.explorer
-  self.adaptive_size = false
-  self.side          = (self.explorer.opts.view.side == "right") and "right" or "left"
-  self.live_filter   = { prev_focused_node = nil, }
-  self.bufnr_by_tabid  = {}
+  self.explorer       = args.explorer
+  self.adaptive_size  = false
+  self.side           = (self.explorer.opts.view.side == "right") and "right" or "left"
+  self.live_filter    = { prev_focused_node = nil, }
+  self.bufnr_by_tabid = {}
 
-  self.winopts       = {
+  self.winopts        = {
     relativenumber = self.explorer.opts.view.relativenumber,
     number         = self.explorer.opts.view.number,
     list           = false,
@@ -246,10 +246,13 @@ end
 ---@private
 ---@param tabid integer
 function View:close_internal(tabid)
+  --- BEGIN multi-instance FF
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:close_internal(t%s)", tabid)
   end
-  if not self:is_visible({ tabpage = tabid }) then
+  --- END multi-instance FF
+
+  if not self:is_visible({ tabpage = tabid }, "View:close_internal") then
     return
   end
   self:save_tab_state(tabid)
@@ -263,9 +266,12 @@ function View:close_internal(tabid)
         vim.api.nvim_set_current_win(vim.fn.win_getid(prev_win))
       end
       if vim.api.nvim_win_is_valid(tree_win or 0) then
+        --- BEGIN multi-instance FF
         if self.explorer.opts.experimental.multi_instance then
           log.line("dev", "View:close_internal(t%s) w%s", tabid, tree_win)
         end
+        --- END multi-instance FF
+        ---
         local success, error = pcall(vim.api.nvim_win_close, tree_win or 0, true)
         if not success then
           notify.debug("Failed to close window: " .. error)
@@ -278,9 +284,12 @@ function View:close_internal(tabid)
 end
 
 function View:close_this_tab_only()
+  --- BEGIN multi-instance FF
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:close_this_tab_only()")
   end
+  --- END multi-instance FF
+
   self:close_internal(vim.api.nvim_get_current_tabpage())
 end
 
@@ -288,9 +297,12 @@ end
 function View:close_all_tabs()
   log.line("dev", "View:close_all_tabs() globals.WINID_BY_TABID=%s", vim.inspect(globals.WINID_BY_TABID))
   for tabid, _ in pairs(globals.WINID_BY_TABID) do
+    --- BEGIN multi-instance FF
     if self.explorer.opts.experimental.multi_instance then
       log.line("dev", "View:close_all_tabs()")
     end
+    --- END multi-instance FF
+
     self:close_internal(tabid)
   end
 end
@@ -298,9 +310,11 @@ end
 ---@param tabid integer|nil
 ---@param callsite string
 function View:close(tabid, callsite)
+  --- BEGIN multi-instance FF
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:close(t%s, %s)", tabid, callsite)
   end
+  --- END multi-instance FF
 
   if self.explorer.opts.tab.sync.close then
     self:close_all_tabs()
@@ -313,7 +327,7 @@ end
 
 ---@param options table|nil
 function View:open(options)
-  if self:is_visible() then
+  if self:is_visible(nil, "View:open") then
     return
   end
 
@@ -405,7 +419,7 @@ function View:resize(size)
     self.width = size
   end
 
-  if not self:is_visible() then
+  if not self:is_visible(nil, "View:resize") then
     return
   end
 
@@ -463,6 +477,7 @@ end
 function View:abandon_current_window()
   local tab = vim.api.nvim_get_current_tabpage()
 
+  --- BEGIN multi-instance FF
   if self.explorer.opts.experimental.multi_instance then
     log.line("dev", "View:abandon_current_window() t%d w%s b%s member b%s %s",
       tab,
@@ -471,8 +486,7 @@ function View:abandon_current_window()
       self.bufnr_by_tabid[tab],
       (globals.BUFNR_BY_TABID[tab] == self.bufnr_by_tabid[tab]) and "" or "MISMATCH")
   end
-
-  -- TODO multi-instance maybe kill the buffer instead of retaining
+  --- END multi-instance FF
 
   -- reset both bufnr registries
   globals.BUFNR_BY_TABID[tab] = nil
@@ -482,7 +496,6 @@ function View:abandon_current_window()
 end
 
 function View:abandon_all_windows()
-  -- TODO multi-instance kill the buffer instead of retaining
   for tab, _ in pairs(vim.api.nvim_list_tabpages()) do
     globals.BUFNR_BY_TABID[tab] = nil
     globals.WINID_BY_TABID[tab] = nil
@@ -490,10 +503,35 @@ function View:abandon_all_windows()
 end
 
 ---@param opts table|nil
+---@param callsite string
 ---@return boolean
-function View:is_visible(opts)
-  -- TODO multi-instance rewrite and consistency check
+function View:is_visible(opts, callsite)
+  local msg
+
+  --- BEGIN multi-instance FF
+  if self.explorer.opts.experimental.multi_instance then
+    msg = string.format("View:is_visible(%s, %-20.20s)", vim.inspect(opts, { newline = "" }), callsite)
+  end
+  --- END multi-instance FF
+
   if opts and opts.tabpage then
+    --- BEGIN multi-instance FF
+    if self.explorer.opts.experimental.multi_instance then
+      local winid = self:winid(opts.tabpage)
+      local winid_by_tabid = opts.tabpage and globals.WINID_BY_TABID[opts.tabpage] or nil
+      msg = string.format("%s globals.WINID_BY_TABID[%s]=w%s view.winid(%s)=w%s",
+        msg,
+        opts.tabpage, winid_by_tabid,
+        opts.tabpage, winid
+      )
+      if winid ~= winid_by_tabid then
+        msg = string.format("%s MISMATCH", msg)
+        notify.error(msg)
+      end
+      log.line("dev", "%s", msg)
+    end
+    --- END multi-instance FF
+
     if not globals.WINID_BY_TABID[opts.tabpage] then
       return false
     end
@@ -502,8 +540,24 @@ function View:is_visible(opts)
   end
 
   if opts and opts.any_tabpage then
-    for _, winid in pairs(globals.WINID_BY_TABID) do
-      if winid and vim.api.nvim_win_is_valid(winid) then
+    for tabid, winid_by_tabid in pairs(globals.WINID_BY_TABID) do
+      --- BEGIN multi-instance FF
+      if self.explorer.opts.experimental.multi_instance then
+        local winid = self:winid(tabid)
+        msg = string.format("%s globals.WINID_BY_TABID[%s]=w%s view.winid(%s)=w%s",
+          msg,
+          tabid, winid_by_tabid,
+          tabid, winid
+        )
+        if winid ~= winid_by_tabid then
+          msg = string.format("%s MISMATCH", msg)
+          notify.error(msg)
+        end
+        log.line("dev", "%s", msg)
+      end
+      --- END multi-instance FF
+
+      if winid_by_tabid and vim.api.nvim_win_is_valid(winid_by_tabid) then
         return true
       end
     end
@@ -516,7 +570,7 @@ end
 
 ---@param opts table|nil
 function View:set_cursor(opts)
-  if self:is_visible() then
+  if self:is_visible(nil, "View:set_cursor") then
     pcall(vim.api.nvim_win_set_cursor, self:get_winid(nil, "View:set_cursor"), opts)
   end
 end
@@ -530,7 +584,7 @@ function View:focus(winid, open_if_closed)
     self:close(nil, "View:focus")
     self:open()
     wid = self:get_winid(nil, "View:focus2")
-  elseif open_if_closed and not self:is_visible() then
+  elseif open_if_closed and not self:is_visible(nil, "View:focus") then
     self:open()
   end
 
@@ -547,7 +601,7 @@ function View:api_winid(opts)
   if tabpage == 0 then
     tabpage = vim.api.nvim_get_current_tabpage()
   end
-  if self:is_visible({ tabpage = tabpage }) then
+  if self:is_visible({ tabpage = tabpage }, "View:api_winid") then
     return self:get_winid(tabpage, "View:winid")
   else
     return nil
@@ -559,8 +613,6 @@ function View:restore_tab_state()
   self:set_cursor(globals.CURSORS[vim.api.nvim_get_current_tabpage()])
 end
 
---- TODO multi-instance remove comment
---- not legacy codepath
 --- winid containing the buffer
 ---@param tabid number|nil (optional) the number of the chosen tabpage. Defaults to current tabpage.
 ---@return integer? winid
@@ -583,8 +635,9 @@ end
 function View:get_winid(tabid, callsite)
   local tabid_param = tabid
   tabid = tabid or vim.api.nvim_get_current_tabpage()
-  local tabinfo_winid = nil
+  local global_winid = nil
 
+  --- BEGIN multi-instance FF
   if self.explorer.opts.experimental.multi_instance then
     local msg_fault = ""
     if not globals.WINID_BY_TABID[tabid] then
@@ -592,33 +645,34 @@ function View:get_winid(tabid, callsite)
     elseif not vim.api.nvim_win_is_valid(globals.WINID_BY_TABID[tabid]) then
       msg_fault = string.format("invalid globals.WINID_BY_TABID[tabid] %d", globals.WINID_BY_TABID[tabid])
     else
-      tabinfo_winid = globals.WINID_BY_TABID[tabid]
+      global_winid = globals.WINID_BY_TABID[tabid]
     end
 
     local winid = self:winid(tabid)
 
-    if winid ~= tabinfo_winid then
+    if winid ~= global_winid then
       msg_fault = "MISMATCH"
     end
 
-    local msg = string.format("View:get_winid(%3s, %-20.20s) globals.TABPAGES[%s]=w%s view.winid(%s)=w%s %s",
+    local msg = string.format("View:get_winid(%3s, %-20.20s) globals.WINID_BY_TABID[%s]=w%s view.winid(%s)=w%s %s",
       tabid_param,
       callsite,
-      tabid, tabinfo_winid,
+      tabid, global_winid,
       tabid, winid,
       msg_fault
     )
 
     log.line("dev", "%s", msg)
 
-    if winid ~= tabinfo_winid then
+    if winid ~= global_winid then
       notify.error(msg)
     end
   end
+  --- END multi-instance FF
 
   -- legacy codepath
-  if tabinfo_winid and vim.api.nvim_win_is_valid(tabinfo_winid) then
-    return tabinfo_winid
+  if global_winid and vim.api.nvim_win_is_valid(global_winid) then
+    return global_winid
   end
 end
 
@@ -627,6 +681,8 @@ end
 ---@return number
 function View:get_bufnr(callsite)
   local tab = vim.api.nvim_get_current_tabpage()
+
+  --- BEGIN multi-instance FF
   if self.explorer.opts.experimental.multi_instance then
     local msg = string.format("View:get_bufnr(%-20.20s) globals.BUFNR_BY_TABID[%s]=b%s view.bufnr_by_tab[%s]=b%s %s",
       callsite,
@@ -641,6 +697,8 @@ function View:get_bufnr(callsite)
 
     log.line("dev", msg)
   end
+  --- END multi-instance FF
+
   return globals.BUFNR_BY_TABID[tab]
 end
 
@@ -657,7 +715,6 @@ function View:prevent_buffer_override()
     local curbuf = vim.api.nvim_win_get_buf(curwin)
     local bufname = vim.api.nvim_buf_get_name(curbuf)
 
-    --- TODO multi-instance this can be removed as winid() will handle it
     if not bufname:match("NvimTree") then
       for i, winid in ipairs(globals.WINID_BY_TABID) do
         if winid == view_winid then

From 4d6c42356a421ec34435743137246becd8c9c201 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 12:36:09 +1000
Subject: [PATCH 13/17] refactor(#2826): more consistency checking

---
 lua/nvim-tree.lua                           | 4 ++--
 lua/nvim-tree/actions/finders/find-file.lua | 4 ++--
 lua/nvim-tree/actions/tree/find-file.lua    | 2 +-
 lua/nvim-tree/actions/tree/open.lua         | 2 +-
 lua/nvim-tree/actions/tree/toggle.lua       | 2 +-
 lua/nvim-tree/explorer/init.lua             | 2 +-
 6 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/lua/nvim-tree.lua b/lua/nvim-tree.lua
index 78a27a7a696..41335c2fb23 100644
--- a/lua/nvim-tree.lua
+++ b/lua/nvim-tree.lua
@@ -74,7 +74,7 @@ end
 
 function M.tab_enter()
   local explorer = core.get_explorer()
-  if explorer and explorer.view:is_visible({ any_tabpage = true }) then
+  if explorer and explorer.view:is_visible({ any_tabpage = true }, "nvim-tree.tab_enter") then
     local bufname = vim.api.nvim_buf_get_name(0)
 
     local ft
@@ -97,7 +97,7 @@ end
 
 function M.open_on_directory()
   local explorer = core.get_explorer()
-  local should_proceed = _config.hijack_directories.auto_open or explorer and explorer.view:is_visible()
+  local should_proceed = _config.hijack_directories.auto_open or explorer and explorer.view:is_visible(nil, "nvim-tree.open_on_directory")
   if not should_proceed then
     return
   end
diff --git a/lua/nvim-tree/actions/finders/find-file.lua b/lua/nvim-tree/actions/finders/find-file.lua
index 2ea494fd85c..2a56b92dbf2 100644
--- a/lua/nvim-tree/actions/finders/find-file.lua
+++ b/lua/nvim-tree/actions/finders/find-file.lua
@@ -13,7 +13,7 @@ local running = {}
 ---@param path string relative or absolute
 function M.fn(path)
   local explorer = core.get_explorer()
-  if not explorer or not explorer.view:is_visible() then
+  if not explorer or not explorer.view:is_visible(nil, "finders/find-file.fn1") then
     return
   end
 
@@ -83,7 +83,7 @@ function M.fn(path)
     end)
     :iterate()
 
-  if found and explorer.view:is_visible() then
+  if found and explorer.view:is_visible(nil, "finders/find-file.fn2") then
     explorer.renderer:draw()
     explorer.view:set_cursor({ line, 0 })
   end
diff --git a/lua/nvim-tree/actions/tree/find-file.lua b/lua/nvim-tree/actions/tree/find-file.lua
index 73d1df3c75e..0694183fd70 100644
--- a/lua/nvim-tree/actions/tree/find-file.lua
+++ b/lua/nvim-tree/actions/tree/find-file.lua
@@ -41,7 +41,7 @@ function M.fn(opts)
   end
 
   local explorer = core.get_explorer()
-  if explorer and explorer.view:is_visible() then
+  if explorer and explorer.view:is_visible(nil, "tree/find-file.fn") then
     -- focus
     if opts.focus then
       lib.set_target_win()
diff --git a/lua/nvim-tree/actions/tree/open.lua b/lua/nvim-tree/actions/tree/open.lua
index 17e2c581a7b..6ee4adf137e 100644
--- a/lua/nvim-tree/actions/tree/open.lua
+++ b/lua/nvim-tree/actions/tree/open.lua
@@ -25,7 +25,7 @@ function M.fn(opts)
 
   local explorer = core.get_explorer()
 
-  if explorer and explorer.view:is_visible() then
+  if explorer and explorer.view:is_visible(nil, "open.fn") then
     -- focus
     lib.set_target_win()
     explorer.view:focus()
diff --git a/lua/nvim-tree/actions/tree/toggle.lua b/lua/nvim-tree/actions/tree/toggle.lua
index d2ba0262a30..d92630361ff 100644
--- a/lua/nvim-tree/actions/tree/toggle.lua
+++ b/lua/nvim-tree/actions/tree/toggle.lua
@@ -42,7 +42,7 @@ function M.fn(opts, no_focus, cwd, bang)
     opts.path = nil
   end
 
-  if explorer and explorer.view:is_visible() then
+  if explorer and explorer.view:is_visible(nil, "toggle.fn") then
     -- close
     explorer.view:close(nil, "toggle.fn")
   else
diff --git a/lua/nvim-tree/explorer/init.lua b/lua/nvim-tree/explorer/init.lua
index 6625d5b0870..947403a6fda 100644
--- a/lua/nvim-tree/explorer/init.lua
+++ b/lua/nvim-tree/explorer/init.lua
@@ -532,7 +532,7 @@ function Explorer:reload_explorer()
 
   local projects = git.reload_all_projects()
   self:refresh_nodes(projects)
-  if self.view:is_visible() then
+  if self.view:is_visible(nil, "Explorer:reload_explorer") then
     self.renderer:draw()
   end
   event_running = false

From d84dfad1c368a44767044f20cc35f0c41c17a2b2 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 12:46:30 +1000
Subject: [PATCH 14/17] refactor(#2826): move global CURSORS to view member

---
 lua/nvim-tree/explorer/view.lua | 11 ++++++-----
 lua/nvim-tree/globals.lua       |  1 -
 lua/nvim-tree/lib.lua           |  3 +--
 3 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 0cbdb899241..a3e6d90000d 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -19,6 +19,7 @@ local Class = require("nvim-tree.classic")
 ---@field private max_width integer
 ---@field private padding integer
 ---@field private bufnr_by_tabid table<integer, integer> stored per tab until multi-instance is complete
+---@field private cursor integer[] as per vim.api.nvim_win_get_cursor
 local View = Class:extend()
 
 ---@class View
@@ -235,12 +236,12 @@ local function switch_buf_if_last_buf()
   end
 end
 
----save_tab_state saves any state that should be preserved across redraws.
+---save any state that should be preserved on reopening
 ---@private
 ---@param tabid integer
 function View:save_tab_state(tabid)
   tabid = tabid or vim.api.nvim_get_current_tabpage()
-  globals.CURSORS[tabid] = vim.api.nvim_win_get_cursor(self:get_winid(tabid, "View:save_tab_state") or 0)
+  self.cursor = vim.api.nvim_win_get_cursor(self:get_winid(tabid, "View:save_tab_state") or 0)
 end
 
 ---@private
@@ -608,9 +609,9 @@ function View:api_winid(opts)
   end
 end
 
---- Restores the state of a NvimTree window if it was initialized before.
-function View:restore_tab_state()
-  self:set_cursor(globals.CURSORS[vim.api.nvim_get_current_tabpage()])
+--- restore any state from last close
+function View:restore_state()
+  self:set_cursor(self.cursor)
 end
 
 --- winid containing the buffer
diff --git a/lua/nvim-tree/globals.lua b/lua/nvim-tree/globals.lua
index 66211260bc6..a2ab7527960 100644
--- a/lua/nvim-tree/globals.lua
+++ b/lua/nvim-tree/globals.lua
@@ -4,7 +4,6 @@ local M = {
   -- from View
   WINID_BY_TABID = {},
   BUFNR_BY_TABID = {},
-  CURSORS = {},
 }
 
 return M
diff --git a/lua/nvim-tree/lib.lua b/lua/nvim-tree/lib.lua
index 854e33bfd09..6c1ef1ef2d1 100644
--- a/lua/nvim-tree/lib.lua
+++ b/lua/nvim-tree/lib.lua
@@ -135,9 +135,8 @@ function M.open(opts)
     open_view_and_draw()
   end
 
-  -- TODO multi-instance is this actually necessary?
   if explorer then
-    explorer.view:restore_tab_state()
+    explorer.view:restore_state()
   end
 end
 

From 82cc80ffa435c9f47c0244007e3af139cc915ae0 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 12:47:04 +1000
Subject: [PATCH 15/17] Revert "refactor(#2826): move global CURSORS to view
 member"

This reverts commit d84dfad1c368a44767044f20cc35f0c41c17a2b2.
---
 lua/nvim-tree/explorer/view.lua | 11 +++++------
 lua/nvim-tree/globals.lua       |  1 +
 lua/nvim-tree/lib.lua           |  3 ++-
 3 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index a3e6d90000d..0cbdb899241 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -19,7 +19,6 @@ local Class = require("nvim-tree.classic")
 ---@field private max_width integer
 ---@field private padding integer
 ---@field private bufnr_by_tabid table<integer, integer> stored per tab until multi-instance is complete
----@field private cursor integer[] as per vim.api.nvim_win_get_cursor
 local View = Class:extend()
 
 ---@class View
@@ -236,12 +235,12 @@ local function switch_buf_if_last_buf()
   end
 end
 
----save any state that should be preserved on reopening
+---save_tab_state saves any state that should be preserved across redraws.
 ---@private
 ---@param tabid integer
 function View:save_tab_state(tabid)
   tabid = tabid or vim.api.nvim_get_current_tabpage()
-  self.cursor = vim.api.nvim_win_get_cursor(self:get_winid(tabid, "View:save_tab_state") or 0)
+  globals.CURSORS[tabid] = vim.api.nvim_win_get_cursor(self:get_winid(tabid, "View:save_tab_state") or 0)
 end
 
 ---@private
@@ -609,9 +608,9 @@ function View:api_winid(opts)
   end
 end
 
---- restore any state from last close
-function View:restore_state()
-  self:set_cursor(self.cursor)
+--- Restores the state of a NvimTree window if it was initialized before.
+function View:restore_tab_state()
+  self:set_cursor(globals.CURSORS[vim.api.nvim_get_current_tabpage()])
 end
 
 --- winid containing the buffer
diff --git a/lua/nvim-tree/globals.lua b/lua/nvim-tree/globals.lua
index a2ab7527960..66211260bc6 100644
--- a/lua/nvim-tree/globals.lua
+++ b/lua/nvim-tree/globals.lua
@@ -4,6 +4,7 @@ local M = {
   -- from View
   WINID_BY_TABID = {},
   BUFNR_BY_TABID = {},
+  CURSORS = {},
 }
 
 return M
diff --git a/lua/nvim-tree/lib.lua b/lua/nvim-tree/lib.lua
index 6c1ef1ef2d1..854e33bfd09 100644
--- a/lua/nvim-tree/lib.lua
+++ b/lua/nvim-tree/lib.lua
@@ -135,8 +135,9 @@ function M.open(opts)
     open_view_and_draw()
   end
 
+  -- TODO multi-instance is this actually necessary?
   if explorer then
-    explorer.view:restore_state()
+    explorer.view:restore_tab_state()
   end
 end
 

From 51b269dc7197829acb8b36bacaa1581f00f17c9b Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 12:52:58 +1000
Subject: [PATCH 16/17] refactor(#2826): move global CURSORS to view member

---
 lua/nvim-tree/explorer/view.lua | 32 ++++++++++++++++++--------------
 lua/nvim-tree/lib.lua           |  3 +--
 2 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 0cbdb899241..802530597b7 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -18,7 +18,10 @@ local Class = require("nvim-tree.classic")
 ---@field private width (fun():integer)|integer|string
 ---@field private max_width integer
 ---@field private padding integer
----@field private bufnr_by_tabid table<integer, integer> stored per tab until multi-instance is complete
+-- TODO multi-instance remove or replace with single member
+---@field private bufnr_by_tabid table<integer, integer>
+-- TODO multi-instance change to single member
+---@field private cursors_by_tabid table<integer, integer[]> as per vim.api.nvim_win_get_cursor
 local View = Class:extend()
 
 ---@class View
@@ -32,13 +35,14 @@ local View = Class:extend()
 function View:new(args)
   args.explorer:log_new("View")
 
-  self.explorer       = args.explorer
-  self.adaptive_size  = false
-  self.side           = (self.explorer.opts.view.side == "right") and "right" or "left"
-  self.live_filter    = { prev_focused_node = nil, }
-  self.bufnr_by_tabid = {}
+  self.explorer         = args.explorer
+  self.adaptive_size    = false
+  self.side             = (self.explorer.opts.view.side == "right") and "right" or "left"
+  self.live_filter      = { prev_focused_node = nil, }
+  self.bufnr_by_tabid   = {}
+  self.cursors_by_tabid = {}
 
-  self.winopts        = {
+  self.winopts          = {
     relativenumber = self.explorer.opts.view.relativenumber,
     number         = self.explorer.opts.view.number,
     list           = false,
@@ -235,12 +239,12 @@ local function switch_buf_if_last_buf()
   end
 end
 
----save_tab_state saves any state that should be preserved across redraws.
+---save any state that should be preserved on reopening
 ---@private
 ---@param tabid integer
-function View:save_tab_state(tabid)
+function View:save_state(tabid)
   tabid = tabid or vim.api.nvim_get_current_tabpage()
-  globals.CURSORS[tabid] = vim.api.nvim_win_get_cursor(self:get_winid(tabid, "View:save_tab_state") or 0)
+  self.cursors_by_tabid[tabid] = vim.api.nvim_win_get_cursor(self:get_winid(tabid, "View:save_tab_state") or 0)
 end
 
 ---@private
@@ -255,7 +259,7 @@ function View:close_internal(tabid)
   if not self:is_visible({ tabpage = tabid }, "View:close_internal") then
     return
   end
-  self:save_tab_state(tabid)
+  self:save_state(tabid)
   switch_buf_if_last_buf()
   local tree_win = self:get_winid(tabid, "View:close_internal")
   local current_win = vim.api.nvim_get_current_win()
@@ -608,9 +612,9 @@ function View:api_winid(opts)
   end
 end
 
---- Restores the state of a NvimTree window if it was initialized before.
-function View:restore_tab_state()
-  self:set_cursor(globals.CURSORS[vim.api.nvim_get_current_tabpage()])
+---restore any state from last close
+function View:restore_state()
+  self:set_cursor(self.cursors_by_tabid[vim.api.nvim_get_current_tabpage()])
 end
 
 --- winid containing the buffer
diff --git a/lua/nvim-tree/lib.lua b/lua/nvim-tree/lib.lua
index 854e33bfd09..6c1ef1ef2d1 100644
--- a/lua/nvim-tree/lib.lua
+++ b/lua/nvim-tree/lib.lua
@@ -135,9 +135,8 @@ function M.open(opts)
     open_view_and_draw()
   end
 
-  -- TODO multi-instance is this actually necessary?
   if explorer then
-    explorer.view:restore_tab_state()
+    explorer.view:restore_state()
   end
 end
 

From 0830436cca6cf00dcd709e76bc4a3476f1c9704e Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Fri, 20 Jun 2025 13:11:21 +1000
Subject: [PATCH 17/17] refactor(#2826): consistency check returns new

---
 lua/nvim-tree/explorer/view.lua | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/lua/nvim-tree/explorer/view.lua b/lua/nvim-tree/explorer/view.lua
index 802530597b7..7fa651e8b8b 100644
--- a/lua/nvim-tree/explorer/view.lua
+++ b/lua/nvim-tree/explorer/view.lua
@@ -533,14 +533,13 @@ function View:is_visible(opts, callsite)
         notify.error(msg)
       end
       log.line("dev", "%s", msg)
-    end
-    --- END multi-instance FF
 
-    if not globals.WINID_BY_TABID[opts.tabpage] then
-      return false
+      return winid and vim.api.nvim_win_is_valid(winid) or false
+      --- END multi-instance FF
+    else
+      local winid = globals.WINID_BY_TABID[opts.tabpage]
+      return winid and vim.api.nvim_win_is_valid(winid)
     end
-    local winid = globals.WINID_BY_TABID[opts.tabpage]
-    return winid and vim.api.nvim_win_is_valid(winid)
   end
 
   if opts and opts.any_tabpage then
@@ -558,11 +557,15 @@ function View:is_visible(opts, callsite)
           notify.error(msg)
         end
         log.line("dev", "%s", msg)
-      end
-      --- END multi-instance FF
 
-      if winid_by_tabid and vim.api.nvim_win_is_valid(winid_by_tabid) then
-        return true
+        if winid and vim.api.nvim_win_is_valid(winid) then
+          return true
+        end
+        --- END multi-instance FF
+      else
+        if winid_by_tabid and vim.api.nvim_win_is_valid(winid_by_tabid) then
+          return true
+        end
       end
     end
     return false
@@ -671,6 +674,8 @@ function View:get_winid(tabid, callsite)
     if winid ~= global_winid then
       notify.error(msg)
     end
+
+    return winid
   end
   --- END multi-instance FF
 
@@ -700,6 +705,8 @@ function View:get_bufnr(callsite)
     end
 
     log.line("dev", msg)
+
+    return self.bufnr_by_tabid[tab]
   end
   --- END multi-instance FF