From 0ee55d0077c972da1678829fed3468539dd2878d Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Mon, 12 Jun 2023 16:50:24 +1000
Subject: [PATCH 1/2] fix(#2240): disable watchers following EMFILE

---
 lua/nvim-tree.lua                        | 60 ++++++++++++++----------
 lua/nvim-tree/actions/fs/copy-paste.lua  | 12 +++--
 lua/nvim-tree/actions/fs/create-file.lua |  4 --
 lua/nvim-tree/actions/fs/remove-file.lua | 15 +++---
 lua/nvim-tree/actions/fs/rename-file.lua |  8 ++--
 lua/nvim-tree/actions/fs/trash.lua       | 15 +++---
 lua/nvim-tree/actions/init.lua           |  1 -
 lua/nvim-tree/explorer/watch.lua         | 15 +++---
 lua/nvim-tree/marks/bulk-move.lua        |  8 ++--
 lua/nvim-tree/watcher.lua                | 25 ++++++++--
 10 files changed, 98 insertions(+), 65 deletions(-)

diff --git a/lua/nvim-tree.lua b/lua/nvim-tree.lua
index ae02eba0a44..78827835762 100644
--- a/lua/nvim-tree.lua
+++ b/lua/nvim-tree.lua
@@ -201,11 +201,14 @@ local function setup_autocommands(opts)
     end,
   })
 
-  local has_watchers = opts.filesystem_watchers.enable
-
-  if opts.auto_reload_on_write and not has_watchers then
-    create_nvim_tree_autocmd("BufWritePost", { callback = reloaders.reload_explorer })
-  end
+  create_nvim_tree_autocmd("BufWritePost", {
+    callback = function()
+      if opts.auto_reload_on_write and not opts.filesystem_watchers.enable then
+        log.line("dev", "BufWritePost reloading")
+        reloaders.reload_explorer()
+      end
+    end,
+  })
 
   create_nvim_tree_autocmd("BufReadPost", {
     callback = function(data)
@@ -235,12 +238,14 @@ local function setup_autocommands(opts)
     end,
   })
 
-  if not has_watchers and opts.git.enable then
-    create_nvim_tree_autocmd("User", {
-      pattern = { "FugitiveChanged", "NeogitStatusRefreshed" },
-      callback = reloaders.reload_git,
-    })
-  end
+  create_nvim_tree_autocmd("User", {
+    pattern = { "FugitiveChanged", "NeogitStatusRefreshed" },
+    callback = function()
+      if not opts.filesystem_watchers.enable and opts.git.enable then
+        reloaders.reload_git()
+      end
+    end,
+  })
 
   if opts.tab.sync.open then
     create_nvim_tree_autocmd("TabEnter", { callback = vim.schedule_wrap(M.tab_enter) })
@@ -276,16 +281,16 @@ local function setup_autocommands(opts)
     create_nvim_tree_autocmd({ "BufEnter", "BufNewFile" }, { callback = M.open_on_directory })
   end
 
-  if opts.reload_on_bufenter and not has_watchers then
-    create_nvim_tree_autocmd("BufEnter", {
-      pattern = "NvimTree_*",
-      callback = function()
+  create_nvim_tree_autocmd("BufEnter", {
+    pattern = "NvimTree_*",
+    callback = function()
+      if opts.reload_on_bufenter and not opts.filesystem_watchers.enable then
         if utils.is_nvim_tree_buf(0) then
           reloaders.reload_explorer()
         end
-      end,
-    })
-  end
+      end
+    end,
+  })
 
   if opts.view.centralize_selection then
     create_nvim_tree_autocmd("BufEnter", {
@@ -639,6 +644,16 @@ local function validate_options(conf)
   end
 end
 
+function M.purge_all_state()
+  require("nvim-tree.watcher").purge_watchers()
+  view.close_all_tabs()
+  view.abandon_all_windows()
+  if core.get_explorer() ~= nil then
+    git.purge_state()
+    TreeExplorer = nil
+  end
+end
+
 function M.setup(conf)
   if vim.fn.has "nvim-0.8" == 0 then
     vim.notify_once("nvim-tree.lua requires Neovim 0.8 or higher", vim.log.levels.WARN)
@@ -687,6 +702,7 @@ function M.setup(conf)
   require("nvim-tree.marks").setup(opts)
   require("nvim-tree.modified").setup(opts)
   require("nvim-tree.help").setup(opts)
+  require("nvim-tree.watcher").setup(opts)
   if M.config.renderer.icons.show.file and pcall(require, "nvim-web-devicons") then
     require("nvim-web-devicons").setup()
   end
@@ -698,13 +714,7 @@ function M.setup(conf)
     commands.setup()
   else
     -- subsequent calls to setup
-    require("nvim-tree.watcher").purge_watchers()
-    view.close_all_tabs()
-    view.abandon_all_windows()
-    if core.get_explorer() ~= nil then
-      git.purge_state()
-      TreeExplorer = nil
-    end
+    M.purge_all_state()
   end
 
   vim.g.NvimTreeSetup = 1
diff --git a/lua/nvim-tree/actions/fs/copy-paste.lua b/lua/nvim-tree/actions/fs/copy-paste.lua
index 79a8f7fa4a9..c59114f80a1 100644
--- a/lua/nvim-tree/actions/fs/copy-paste.lua
+++ b/lua/nvim-tree/actions/fs/copy-paste.lua
@@ -7,7 +7,9 @@ local notify = require "nvim-tree.notify"
 
 local find_file = require("nvim-tree.actions.finders.find-file").fn
 
-local M = {}
+local M = {
+  config = {}
+}
 
 local clipboard = {
   move = {},
@@ -175,7 +177,7 @@ local function do_paste(node, action_type, action_fn)
   end
 
   clipboard[action_type] = {}
-  if M.enable_reload then
+  if not M.config.filesystem_watchers.enable then
     return require("nvim-tree.actions.reloaders.reloaders").reload_explorer()
   end
 end
@@ -226,7 +228,7 @@ function M.print_clipboard()
 end
 
 local function copy_to_clipboard(content)
-  if M.use_system_clipboard == true then
+  if M.config.actions.use_system_clipboard == true then
     vim.fn.setreg("+", content)
     vim.fn.setreg('"', content)
     return notify.info(string.format("Copied %s to system clipboard!", content))
@@ -255,8 +257,8 @@ function M.copy_absolute_path(node)
 end
 
 function M.setup(opts)
-  M.use_system_clipboard = opts.actions.use_system_clipboard
-  M.enable_reload = not opts.filesystem_watchers.enable
+  M.config.filesystem_watchers = opts.filesystem_watchers
+  M.config.actions = opts.actions
 end
 
 return M
diff --git a/lua/nvim-tree/actions/fs/create-file.lua b/lua/nvim-tree/actions/fs/create-file.lua
index cd0a83800f1..74f4ff37565 100644
--- a/lua/nvim-tree/actions/fs/create-file.lua
+++ b/lua/nvim-tree/actions/fs/create-file.lua
@@ -96,8 +96,4 @@ function M.fn(node)
   end)
 end
 
-function M.setup(opts)
-  M.enable_reload = not opts.filesystem_watchers.enable
-end
-
 return M
diff --git a/lua/nvim-tree/actions/fs/remove-file.lua b/lua/nvim-tree/actions/fs/remove-file.lua
index 9acf6c516b0..5cf8d1c447e 100644
--- a/lua/nvim-tree/actions/fs/remove-file.lua
+++ b/lua/nvim-tree/actions/fs/remove-file.lua
@@ -4,7 +4,9 @@ local view = require "nvim-tree.view"
 local lib = require "nvim-tree.lib"
 local notify = require "nvim-tree.notify"
 
-local M = {}
+local M = {
+  config = {}
+}
 
 local function close_windows(windows)
   if view.View.float.enable and #vim.api.nvim_list_wins() == 1 then
@@ -31,7 +33,7 @@ local function clear_buffer(absolute_path)
         end
       end
       vim.api.nvim_buf_delete(buf.bufnr, { force = true })
-      if M.close_window then
+      if M.config.actions.remove_file.close_window then
         close_windows(buf.windows)
       end
       return
@@ -90,7 +92,7 @@ function M.fn(node)
       clear_buffer(node.absolute_path)
     end
     notify.info(node.absolute_path .. " was properly removed.")
-    if M.enable_reload then
+    if not M.config.filesystem_watchers.enable then
       require("nvim-tree.actions.reloaders.reloaders").reload_explorer()
     end
   end
@@ -110,10 +112,9 @@ function M.fn(node)
 end
 
 function M.setup(opts)
-  M.config = {}
-  M.config.ui = opts.ui or {}
-  M.enable_reload = not opts.filesystem_watchers.enable
-  M.close_window = opts.actions.remove_file.close_window
+  M.config.ui = opts.ui
+  M.config.actions = opts.actions
+  M.config.filesystem_watchers = opts.filesystem_watchers
 end
 
 return M
diff --git a/lua/nvim-tree/actions/fs/rename-file.lua b/lua/nvim-tree/actions/fs/rename-file.lua
index fd6ad85b13a..11fbe2ce50b 100644
--- a/lua/nvim-tree/actions/fs/rename-file.lua
+++ b/lua/nvim-tree/actions/fs/rename-file.lua
@@ -5,7 +5,9 @@ local notify = require "nvim-tree.notify"
 
 local find_file = require("nvim-tree.actions.finders.find-file").fn
 
-local M = {}
+local M = {
+  config = {}
+}
 
 local ALLOWED_MODIFIERS = {
   [":p:h"] = true,
@@ -83,7 +85,7 @@ function M.fn(default_modifier)
       end
 
       M.rename(node, prepend .. new_file_path .. append)
-      if M.enable_reload then
+      if not M.config.filesystem_watchers.enable then
         require("nvim-tree.actions.reloaders.reloaders").reload_explorer()
       end
 
@@ -93,7 +95,7 @@ function M.fn(default_modifier)
 end
 
 function M.setup(opts)
-  M.enable_reload = not opts.filesystem_watchers.enable
+  M.config.filesystem_watchers = opts.filesystem_watchers
 end
 
 return M
diff --git a/lua/nvim-tree/actions/fs/trash.lua b/lua/nvim-tree/actions/fs/trash.lua
index ea38511a843..b208e2d7aab 100644
--- a/lua/nvim-tree/actions/fs/trash.lua
+++ b/lua/nvim-tree/actions/fs/trash.lua
@@ -1,7 +1,9 @@
 local lib = require "nvim-tree.lib"
 local notify = require "nvim-tree.notify"
 
-local M = {}
+local M = {
+  config = {}
+}
 
 local utils = require "nvim-tree.utils"
 local events = require "nvim-tree.events"
@@ -68,7 +70,7 @@ function M.fn(node)
           return
         end
         events._dispatch_folder_removed(node.absolute_path)
-        if M.enable_reload then
+        if not M.config.filesystem_watchers.enable then
           require("nvim-tree.actions.reloaders.reloaders").reload_explorer()
         end
       end)
@@ -80,7 +82,7 @@ function M.fn(node)
         end
         events._dispatch_file_removed(node.absolute_path)
         clear_buffer(node.absolute_path)
-        if M.enable_reload then
+        if not M.config.filesystem_watchers.enable then
           require("nvim-tree.actions.reloaders.reloaders").reload_explorer()
         end
       end)
@@ -102,10 +104,9 @@ function M.fn(node)
 end
 
 function M.setup(opts)
-  M.config = {}
-  M.config.ui = opts.ui or {}
-  M.config.trash = opts.trash or {}
-  M.enable_reload = not opts.filesystem_watchers.enable
+  M.config.ui = opts.ui
+  M.config.trash = opts.trash
+  M.config.filesystem_watchers = opts.filesystem_watchers
 end
 
 return M
diff --git a/lua/nvim-tree/actions/init.lua b/lua/nvim-tree/actions/init.lua
index a2798b5aec3..d845296a9d4 100644
--- a/lua/nvim-tree/actions/init.lua
+++ b/lua/nvim-tree/actions/init.lua
@@ -6,7 +6,6 @@ function M.setup(opts)
   require("nvim-tree.actions.node.file-popup").setup(opts)
   require("nvim-tree.actions.node.open-file").setup(opts)
   require("nvim-tree.actions.root.change-dir").setup(opts)
-  require("nvim-tree.actions.fs.create-file").setup(opts)
   require("nvim-tree.actions.fs.rename-file").setup(opts)
   require("nvim-tree.actions.fs.remove-file").setup(opts)
   require("nvim-tree.actions.fs.copy-paste").setup(opts)
diff --git a/lua/nvim-tree/explorer/watch.lua b/lua/nvim-tree/explorer/watch.lua
index 50afb5a3da8..dad1738c4f5 100644
--- a/lua/nvim-tree/explorer/watch.lua
+++ b/lua/nvim-tree/explorer/watch.lua
@@ -2,7 +2,10 @@ local log = require "nvim-tree.log"
 local utils = require "nvim-tree.utils"
 local Watcher = require("nvim-tree.watcher").Watcher
 
-local M = {}
+local M = {
+  config = {},
+  uid = 0,
+}
 
 local function is_git(path)
   return vim.fn.fnamemodify(path, ":t") == ".git"
@@ -23,7 +26,7 @@ local function is_folder_ignored(path)
     end
   end
 
-  for _, ignore_dir in ipairs(M.ignore_dirs) do
+  for _, ignore_dir in ipairs(M.config.filesystem_watchers.ignore_dirs) do
     if vim.fn.match(path, ignore_dir) ~= -1 then
       return true
     end
@@ -33,7 +36,7 @@ local function is_folder_ignored(path)
 end
 
 function M.create_watcher(node)
-  if not M.enabled or type(node) ~= "table" then
+  if not M.config.filesystem_watchers.enable or type(node) ~= "table" then
     return nil
   end
 
@@ -50,7 +53,7 @@ function M.create_watcher(node)
 
   local function callback(watcher)
     log.line("watcher", "node event scheduled refresh %s", watcher.context)
-    utils.debounce(watcher.context, M.debounce_delay, function()
+    utils.debounce(watcher.context, M.config.filesystem_watchers.debounce_delay, function()
       if watcher.destroyed then
         return
       end
@@ -72,9 +75,7 @@ function M.create_watcher(node)
 end
 
 function M.setup(opts)
-  M.enabled = opts.filesystem_watchers.enable
-  M.debounce_delay = opts.filesystem_watchers.debounce_delay
-  M.ignore_dirs = opts.filesystem_watchers.ignore_dirs
+  M.config.filesystem_watchers = opts.filesystem_watchers
   M.uid = 0
 end
 
diff --git a/lua/nvim-tree/marks/bulk-move.lua b/lua/nvim-tree/marks/bulk-move.lua
index ee0e2e8b2ac..9384c21f7f6 100644
--- a/lua/nvim-tree/marks/bulk-move.lua
+++ b/lua/nvim-tree/marks/bulk-move.lua
@@ -4,7 +4,9 @@ local utils = require "nvim-tree.utils"
 local FsRename = require "nvim-tree.actions.fs.rename-file"
 local notify = require "nvim-tree.notify"
 
-local M = {}
+local M = {
+  config = {},
+}
 
 function M.bulk_move()
   if #Marks.get_marks() == 0 then
@@ -29,14 +31,14 @@ function M.bulk_move()
       FsRename.rename(node, to)
     end
 
-    if M.enable_reload then
+    if not M.config.filesystem_watchers.enable then
       require("nvim-tree.actions.reloaders.reloaders").reload_explorer()
     end
   end)
 end
 
 function M.setup(opts)
-  M.enable_reload = not opts.filesystem_watchers.enable
+  M.config.filesystem_watchers = opts.filesystem_watchers
 end
 
 return M
diff --git a/lua/nvim-tree/watcher.lua b/lua/nvim-tree/watcher.lua
index 26f463eb955..7dd00529aac 100644
--- a/lua/nvim-tree/watcher.lua
+++ b/lua/nvim-tree/watcher.lua
@@ -1,9 +1,10 @@
 local notify = require "nvim-tree.notify"
-
 local log = require "nvim-tree.log"
 local utils = require "nvim-tree.utils"
 
-local M = {}
+local M = {
+  config = {}
+}
 
 local Event = {
   _events = {},
@@ -72,7 +73,12 @@ function Event:start()
 
   rc, _, name = self._fs_event:start(self._path, FS_EVENT_FLAGS, event_cb)
   if rc ~= 0 then
-    notify.warn(string.format("Could not start the fs_event watcher for path %s : %s", self._path, name))
+    local warning = string.format("Could not start the fs_event watcher for path %s : %s", self._path, name)
+    if name == "EMFILE" then
+      M.disable_watchers(warning, "Please see https://github.com/nvim-tree/nvim-tree.lua/wiki/Troubleshooting#could-not-start-fs_event-for-path--emfile")
+    else
+      notify.warn(warning)
+    end
     return false
   end
 
@@ -154,6 +160,15 @@ end
 
 M.Watcher = Watcher
 
+--- Permanently disable watchers and purge all state following a catastrophic error.
+--- @param warning string
+--- @param detail string
+function M.disable_watchers(warning, detail)
+  notify.warn(string.format("%s Disabling watchers: %s", warning, detail))
+  M.config.filesystem_watchers.enable = false
+  require("nvim-tree").purge_all_state()
+end
+
 function M.purge_watchers()
   log.line("watcher", "purge_watchers")
 
@@ -191,4 +206,8 @@ function M.is_fs_event_capable(path)
   return true
 end
 
+function M.setup(opts)
+  M.config.filesystem_watchers = opts.filesystem_watchers
+end
+
 return M

From 03d5c01956a2d9e12d50d73a2de5fc85da7c79cc Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Mon, 12 Jun 2023 16:53:51 +1000
Subject: [PATCH 2/2] fix(#2240): disable watchers following EMFILE

---
 lua/nvim-tree/actions/fs/copy-paste.lua  | 2 +-
 lua/nvim-tree/actions/fs/remove-file.lua | 2 +-
 lua/nvim-tree/actions/fs/rename-file.lua | 2 +-
 lua/nvim-tree/actions/fs/trash.lua       | 2 +-
 lua/nvim-tree/watcher.lua                | 7 +++++--
 5 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/lua/nvim-tree/actions/fs/copy-paste.lua b/lua/nvim-tree/actions/fs/copy-paste.lua
index c59114f80a1..406272913d9 100644
--- a/lua/nvim-tree/actions/fs/copy-paste.lua
+++ b/lua/nvim-tree/actions/fs/copy-paste.lua
@@ -8,7 +8,7 @@ local notify = require "nvim-tree.notify"
 local find_file = require("nvim-tree.actions.finders.find-file").fn
 
 local M = {
-  config = {}
+  config = {},
 }
 
 local clipboard = {
diff --git a/lua/nvim-tree/actions/fs/remove-file.lua b/lua/nvim-tree/actions/fs/remove-file.lua
index 5cf8d1c447e..6b91b1df0a2 100644
--- a/lua/nvim-tree/actions/fs/remove-file.lua
+++ b/lua/nvim-tree/actions/fs/remove-file.lua
@@ -5,7 +5,7 @@ local lib = require "nvim-tree.lib"
 local notify = require "nvim-tree.notify"
 
 local M = {
-  config = {}
+  config = {},
 }
 
 local function close_windows(windows)
diff --git a/lua/nvim-tree/actions/fs/rename-file.lua b/lua/nvim-tree/actions/fs/rename-file.lua
index 11fbe2ce50b..9e686e41dab 100644
--- a/lua/nvim-tree/actions/fs/rename-file.lua
+++ b/lua/nvim-tree/actions/fs/rename-file.lua
@@ -6,7 +6,7 @@ local notify = require "nvim-tree.notify"
 local find_file = require("nvim-tree.actions.finders.find-file").fn
 
 local M = {
-  config = {}
+  config = {},
 }
 
 local ALLOWED_MODIFIERS = {
diff --git a/lua/nvim-tree/actions/fs/trash.lua b/lua/nvim-tree/actions/fs/trash.lua
index b208e2d7aab..137468ce8e7 100644
--- a/lua/nvim-tree/actions/fs/trash.lua
+++ b/lua/nvim-tree/actions/fs/trash.lua
@@ -2,7 +2,7 @@ local lib = require "nvim-tree.lib"
 local notify = require "nvim-tree.notify"
 
 local M = {
-  config = {}
+  config = {},
 }
 
 local utils = require "nvim-tree.utils"
diff --git a/lua/nvim-tree/watcher.lua b/lua/nvim-tree/watcher.lua
index 7dd00529aac..efa5246963e 100644
--- a/lua/nvim-tree/watcher.lua
+++ b/lua/nvim-tree/watcher.lua
@@ -3,7 +3,7 @@ local log = require "nvim-tree.log"
 local utils = require "nvim-tree.utils"
 
 local M = {
-  config = {}
+  config = {},
 }
 
 local Event = {
@@ -75,7 +75,10 @@ function Event:start()
   if rc ~= 0 then
     local warning = string.format("Could not start the fs_event watcher for path %s : %s", self._path, name)
     if name == "EMFILE" then
-      M.disable_watchers(warning, "Please see https://github.com/nvim-tree/nvim-tree.lua/wiki/Troubleshooting#could-not-start-fs_event-for-path--emfile")
+      M.disable_watchers(
+        warning,
+        "Please see https://github.com/nvim-tree/nvim-tree.lua/wiki/Troubleshooting#could-not-start-fs_event-for-path--emfile"
+      )
     else
       notify.warn(warning)
     end