feat(watcher): fs_poll -> fs_event, destroy nodes/watchers (#1431)

Author: alex-courtis

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

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,

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)

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)
   )
 

lua/nvim-tree/explorer/watch.lua

@@ -46,7 +46,7 @@ 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)

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

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
@@ -35,48 +42,55 @@ 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
 
   return self
 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)
+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
-      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._e = nil
+  end
+  for i, w in ipairs(M._watchers) do
+    if w == self then
+      table.remove(M._watchers, i)
+      break
     end
-    self._p = nil
   end
 end
 
 M.Watcher = Watcher
 
 function M.purge_watchers()
   for _, watcher in pairs(M._watchers) do
-    watcher:stop()
+    watcher:destroy()
   end
   M._watchers = {}
 end