From 1c08e96ddd4f387edb4ce9d305e528dec7695352 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Sun, 17 Jul 2022 14:50:50 +1000
Subject: [PATCH 1/4] feat(watcher): fs_poll -> fs_event

---
 lua/nvim-tree/git/init.lua |  6 +++---
 lua/nvim-tree/watcher.lua  | 32 ++++++++++++++++++++------------
 2 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/lua/nvim-tree/git/init.lua b/lua/nvim-tree/git/init.lua
index c1eb094835e..761677d042e 100644
--- a/lua/nvim-tree/git/init.lua
+++ b/lua/nvim-tree/git/init.lua
@@ -29,8 +29,8 @@ function M.reload_project(project_root, path)
     return
   end
 
-  if path and not path:match("^" .. project_root) then
-    path = nil
+  if path and path:find(project_root, 1, true) ~= 1 then
+    return
   end
 
   local git_status = Runner.run {
@@ -43,7 +43,7 @@ function M.reload_project(project_root, path)
 
   if path then
     for p in pairs(project.files) do
-      if p:match("^" .. path) then
+      if p:find(path, 1, true) == 1 then
         project.files[p] = nil
       end
     end
diff --git a/lua/nvim-tree/watcher.lua b/lua/nvim-tree/watcher.lua
index 15ebeb90296..79a95981a13 100644
--- a/lua/nvim-tree/watcher.lua
+++ b/lua/nvim-tree/watcher.lua
@@ -9,6 +9,13 @@ local M = {
 local Watcher = {}
 Watcher.__index = Watcher
 
+local FS_EVENT_FLAGS = {
+  -- inotify or equivalent will be used; fallback to stat has not yet been implemented
+  stat = false,
+  -- recursive is not functional in neovim's libuv implementation
+  recursive = false,
+}
+
 function Watcher.new(opts)
   for _, existing in ipairs(M._watchers) do
     if existing._opts.absolute_path == opts.absolute_path then
@@ -35,26 +42,27 @@ function Watcher:start()
 
   local rc, _, name
 
-  self._p, _, name = uv.new_fs_poll()
-  if not self._p then
-    self._p = nil
+  self._e, _, name = uv.new_fs_event()
+  if not self._e then
+    self._e = nil
     utils.warn(
-      string.format("Could not initialize an fs_poll watcher for path %s : %s", self._opts.absolute_path, name)
+      string.format("Could not initialize an fs_event watcher for path %s : %s", self._opts.absolute_path, name)
     )
     return nil
   end
 
-  local poll_cb = vim.schedule_wrap(function(err)
+  local event_cb = vim.schedule_wrap(function(err, filename, events)
     if err then
-      log.line("watcher", "poll_cb for %s fail : %s", self._opts.absolute_path, err)
+      log.line("watcher", "event_cb for %s fail : %s", self._opts.absolute_path, err)
     else
+      log.line("watcher", "event_cb '%s' '%s' %s", self._opts.absolute_path, filename, vim.inspect(events))
       self._opts.on_event(self._opts)
     end
   end)
 
-  rc, _, name = uv.fs_poll_start(self._p, self._opts.absolute_path, self._opts.interval, poll_cb)
+  rc, _, name = self._e:start(self._opts.absolute_path, FS_EVENT_FLAGS, event_cb)
   if rc ~= 0 then
-    utils.warn(string.format("Could not start the fs_poll watcher for path %s : %s", self._opts.absolute_path, name))
+    utils.warn(string.format("Could not start the fs_event watcher for path %s : %s", self._opts.absolute_path, name))
     return nil
   end
 
@@ -63,12 +71,12 @@ end
 
 function Watcher:stop()
   log.line("watcher", "Watcher:stop  '%s'", self._opts.absolute_path)
-  if self._p then
-    local rc, _, name = uv.fs_poll_stop(self._p)
+  if self._e then
+    local rc, _, name = self._e:stop()
     if rc ~= 0 then
-      utils.warn(string.format("Could not stop the fs_poll watcher for path %s : %s", self._opts.absolute_path, name))
+      utils.warn(string.format("Could not stop the fs_event watcher for path %s : %s", self._opts.absolute_path, name))
     end
-    self._p = nil
+    self._e = nil
   end
 end
 

From 054da049c72629f92b1a5f813a81f69caaf02b08 Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Sun, 17 Jul 2022 15:06:56 +1000
Subject: [PATCH 2/4] feat(watcher): stop destroyed node's watchers

---
 lua/nvim-tree/explorer/watch.lua | 3 ++-
 lua/nvim-tree/watcher.lua        | 6 ++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/lua/nvim-tree/explorer/watch.lua b/lua/nvim-tree/explorer/watch.lua
index 2243df2ada8..9864f0d9009 100644
--- a/lua/nvim-tree/explorer/watch.lua
+++ b/lua/nvim-tree/explorer/watch.lua
@@ -46,12 +46,13 @@ function M.create_watcher(absolute_path)
   end
 
   log.line("watcher", "node start '%s'", absolute_path)
-  Watcher.new {
+  return Watcher.new {
     absolute_path = absolute_path,
     interval = M.interval,
     on_event = function(opts)
       log.line("watcher", "node event scheduled '%s'", opts.absolute_path)
       utils.debounce("explorer:watch:" .. opts.absolute_path, M.debounce_delay, function()
+        log.line("watcher", "node refreshing '%s'", absolute_path)
         refresh_path(opts.absolute_path)
       end)
     end,
diff --git a/lua/nvim-tree/watcher.lua b/lua/nvim-tree/watcher.lua
index 79a95981a13..cc83de00d5a 100644
--- a/lua/nvim-tree/watcher.lua
+++ b/lua/nvim-tree/watcher.lua
@@ -78,6 +78,12 @@ function Watcher:stop()
     end
     self._e = nil
   end
+  for i, w in ipairs(M._watchers) do
+    if w == self then
+      table.remove(M._watchers, i)
+      break
+    end
+  end
 end
 
 M.Watcher = Watcher

From 263e3fe09977506efcc6a6d3e13f89853219aa5c Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Sun, 17 Jul 2022 16:00:24 +1000
Subject: [PATCH 3/4] feat(watcher): destroy nodes / watchers

---
 lua/nvim-tree/core.lua            |  2 +-
 lua/nvim-tree/explorer/common.lua | 10 ++++++++++
 lua/nvim-tree/explorer/init.lua   | 17 ++++++-----------
 lua/nvim-tree/explorer/reload.lua |  7 ++++++-
 lua/nvim-tree/watcher.lua         |  6 +++---
 5 files changed, 26 insertions(+), 16 deletions(-)

diff --git a/lua/nvim-tree/core.lua b/lua/nvim-tree/core.lua
index 83f3db92877..a61fea72743 100644
--- a/lua/nvim-tree/core.lua
+++ b/lua/nvim-tree/core.lua
@@ -10,7 +10,7 @@ local first_init_done = false
 
 function M.init(foldername)
   if TreeExplorer then
-    TreeExplorer:_clear_watchers()
+    TreeExplorer:destroy()
   end
   TreeExplorer = explorer.Explorer.new(foldername)
   if not first_init_done then
diff --git a/lua/nvim-tree/explorer/common.lua b/lua/nvim-tree/explorer/common.lua
index 14cef92b92a..e3c3e76d32a 100644
--- a/lua/nvim-tree/explorer/common.lua
+++ b/lua/nvim-tree/explorer/common.lua
@@ -43,6 +43,16 @@ function M.update_git_status(node, parent_ignored, status)
   end
 end
 
+function M.node_destroy(node)
+  if not node then
+    return
+  end
+
+  if node.watcher then
+    node.watcher:destroy()
+  end
+end
+
 function M.setup(opts)
   M.config = {
     git = opts.git,
diff --git a/lua/nvim-tree/explorer/init.lua b/lua/nvim-tree/explorer/init.lua
index 5578331f67c..6b9a8c9e5cc 100644
--- a/lua/nvim-tree/explorer/init.lua
+++ b/lua/nvim-tree/explorer/init.lua
@@ -2,6 +2,7 @@ local uv = vim.loop
 
 local git = require "nvim-tree.git"
 local watch = require "nvim-tree.explorer.watch"
+local common = require "nvim-tree.explorer.common"
 
 local M = {}
 
@@ -33,22 +34,16 @@ function Explorer:expand(node)
   self:_load(node)
 end
 
-function Explorer.clear_watchers_for(root_node)
+function Explorer:destroy()
   local function iterate(node)
-    if node.watcher then
-      node.watcher:stop()
+    common.node_destroy(node)
+    if node.nodes then
       for _, child in pairs(node.nodes) do
-        if child.watcher then
-          iterate(child)
-        end
+        iterate(child)
       end
     end
   end
-  iterate(root_node)
-end
-
-function Explorer:_clear_watchers()
-  Explorer.clear_watchers_for(self)
+  iterate(self)
 end
 
 function M.setup(opts)
diff --git a/lua/nvim-tree/explorer/reload.lua b/lua/nvim-tree/explorer/reload.lua
index e26a68b0a92..5d9299b7830 100644
--- a/lua/nvim-tree/explorer/reload.lua
+++ b/lua/nvim-tree/explorer/reload.lua
@@ -69,7 +69,12 @@ function M.reload(node, status)
   node.nodes = vim.tbl_map(
     update_status(nodes_by_path, node_ignored, status),
     vim.tbl_filter(function(n)
-      return child_names[n.absolute_path]
+      if child_names[n.absolute_path] then
+        return child_names[n.absolute_path]
+      else
+        common.node_destroy(n)
+        return nil
+      end
     end, node.nodes)
   )
 
diff --git a/lua/nvim-tree/watcher.lua b/lua/nvim-tree/watcher.lua
index cc83de00d5a..3ab7a42d8b2 100644
--- a/lua/nvim-tree/watcher.lua
+++ b/lua/nvim-tree/watcher.lua
@@ -69,8 +69,8 @@ function Watcher:start()
   return self
 end
 
-function Watcher:stop()
-  log.line("watcher", "Watcher:stop  '%s'", self._opts.absolute_path)
+function Watcher:destroy()
+  log.line("watcher", "Watcher:destroy '%s'", self._opts.absolute_path)
   if self._e then
     local rc, _, name = self._e:stop()
     if rc ~= 0 then
@@ -90,7 +90,7 @@ M.Watcher = Watcher
 
 function M.purge_watchers()
   for _, watcher in pairs(M._watchers) do
-    watcher:stop()
+    watcher:destroy()
   end
   M._watchers = {}
 end

From 4e7c5d7a832006b5524e711cac7f9922742f0bca Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Sun, 17 Jul 2022 16:07:25 +1000
Subject: [PATCH 4/4] feat(watcher): destroy nodes / watchers

---
 lua/nvim-tree/explorer/watch.lua | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lua/nvim-tree/explorer/watch.lua b/lua/nvim-tree/explorer/watch.lua
index 9864f0d9009..79b50fc57c0 100644
--- a/lua/nvim-tree/explorer/watch.lua
+++ b/lua/nvim-tree/explorer/watch.lua
@@ -52,7 +52,6 @@ function M.create_watcher(absolute_path)
     on_event = function(opts)
       log.line("watcher", "node event scheduled '%s'", opts.absolute_path)
       utils.debounce("explorer:watch:" .. opts.absolute_path, M.debounce_delay, function()
-        log.line("watcher", "node refreshing '%s'", absolute_path)
         refresh_path(opts.absolute_path)
       end)
     end,