From 8a4e7d22dea7d82ec5ab2d6cf10307e557944b8a Mon Sep 17 00:00:00 2001
From: Alexander Courtis <alex@courtis.org>
Date: Mon, 9 Jan 2023 13:56:35 +1100
Subject: [PATCH] fix(#1822): test directory capable of watching before
 presenting it

---
 lua/nvim-tree/explorer/explore.lua |  8 +++++++-
 lua/nvim-tree/explorer/reload.lua  |  3 ++-
 lua/nvim-tree/watcher.lua          | 25 +++++++++++++++++++++++++
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/lua/nvim-tree/explorer/explore.lua b/lua/nvim-tree/explorer/explore.lua
index a8aed702a54..9bacea3e187 100644
--- a/lua/nvim-tree/explorer/explore.lua
+++ b/lua/nvim-tree/explorer/explore.lua
@@ -6,6 +6,8 @@ local filters = require "nvim-tree.explorer.filters"
 local live_filter = require "nvim-tree.live-filter"
 local log = require "nvim-tree.log"
 
+local Watcher = require "nvim-tree.watcher"
+
 local M = {}
 
 local function get_type_from(type_, cwd)
@@ -28,7 +30,11 @@ local function populate_children(handle, cwd, node, git_status)
     local ps = log.profile_start(pn)
 
     t = get_type_from(t, abs)
-    if not filters.should_filter(abs, filter_status) and not nodes_by_path[abs] then
+    if
+      not filters.should_filter(abs, filter_status)
+      and not nodes_by_path[abs]
+      and Watcher.is_fs_event_capable(abs)
+    then
       local child = nil
       if t == "directory" and vim.loop.fs_access(abs, "R") then
         child = builders.folder(node, abs, name)
diff --git a/lua/nvim-tree/explorer/reload.lua b/lua/nvim-tree/explorer/reload.lua
index 5f6a6ce419b..e7a58049414 100644
--- a/lua/nvim-tree/explorer/reload.lua
+++ b/lua/nvim-tree/explorer/reload.lua
@@ -8,6 +8,7 @@ local git = require "nvim-tree.git"
 local log = require "nvim-tree.log"
 
 local NodeIterator = require "nvim-tree.iterators.node-iterator"
+local Watcher = require "nvim-tree.watcher"
 
 local M = {}
 
@@ -86,7 +87,7 @@ function M.reload(node, git_status, unloaded_bufnr)
       end
 
       if not nodes_by_path[abs] then
-        if t == "directory" and vim.loop.fs_access(abs, "R") then
+        if t == "directory" and vim.loop.fs_access(abs, "R") and Watcher.is_fs_event_capable(abs) then
           local folder = builders.folder(node, abs, name)
           nodes_by_path[abs] = folder
           table.insert(node.nodes, folder)
diff --git a/lua/nvim-tree/watcher.lua b/lua/nvim-tree/watcher.lua
index b5473ca62c3..97f3a52b5f1 100644
--- a/lua/nvim-tree/watcher.lua
+++ b/lua/nvim-tree/watcher.lua
@@ -159,4 +159,29 @@ function M.purge_watchers()
   end
 end
 
+--- Windows NT will present directories that cannot be enumerated.
+--- Detect these by attempting to start an event monitor.
+--- @param path string
+--- @return boolean
+function M.is_fs_event_capable(path)
+  if not utils.is_windows then
+    return true
+  end
+
+  local fs_event = vim.loop.new_fs_event()
+  if not fs_event then
+    return false
+  end
+
+  if fs_event:start(path, FS_EVENT_FLAGS, function() end) ~= 0 then
+    return false
+  end
+
+  if fs_event:stop() ~= 0 then
+    return false
+  end
+
+  return true
+end
+
 return M