feat(#2225): add renderer.hidden_display to show a summary of hidden files below the tree (#2856)

* feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

* feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

* feat(icon_placement): consolidate doc

* fix: extra namespace added to avoid colision between right_align and full_name features

* feat(hidden_display): Allow fine grained rendering of hidden files in
a folder

* feat(hidden_display): update defaults in Builder to allow rendering

* feat(hidden_display): Rename opts function name for the feature

* feat(#2349): add "right_align" option for renderer.icons.*_placement (#2846)

* feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

* feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

feat(icon_placement): Allow right_align icon_placemente for decorator using ext_marks nvim api

* feat(icon_placement): consolidate doc

* fix: extra namespace added to avoid colision between right_align and full_name features

* style: rename namespace_id

---------

Co-authored-by: Alexander Courtis <alex@courtis.org>

* docs: update docs

* feat(hidden_display): Simplification and better performance by not sorting and grouping virtual lines

* Update doc/nvim-tree-lua.txt

Co-authored-by: Alexander Courtis <alex@courtis.org>

* style: hidden_stats is better

* docs: change to hidden_stats

* add separate namespace for virtual lines

* help: add highlight group

---------

Co-authored-by: Alexander Courtis <alex@courtis.org>

lua/nvim-tree/explorer/explore.lua

@@ -5,6 +5,7 @@ local git = require "nvim-tree.git"
 local live_filter = require "nvim-tree.live-filter"
 local log = require "nvim-tree.log"
 
+local FILTER_REASON = require("nvim-tree.enum").FILTER_REASON
 local Watcher = require "nvim-tree.watcher"
 
 local M = {}
@@ -17,7 +18,17 @@ local M = {}
 local function populate_children(handle, cwd, node, git_status, parent)
   local node_ignored = explorer_node.is_git_ignored(node)
   local nodes_by_path = utils.bool_record(node.nodes, "absolute_path")
+
   local filter_status = parent.filters:prepare(git_status)
+
+  node.hidden_stats = vim.tbl_deep_extend("force", node.hidden_stats or {}, {
+    git = 0,
+    buf = 0,
+    dotfile = 0,
+    custom = 0,
+    bookmark = 0,
+  })
+
   while true do
     local name, t = vim.loop.fs_scandir_next(handle)
     if not name then
@@ -29,8 +40,8 @@ local function populate_children(handle, cwd, node, git_status, parent)
 
     ---@type uv.fs_stat.result|nil
     local stat = vim.loop.fs_stat(abs)
-
-    if not parent.filters:should_filter(abs, stat, filter_status) and not nodes_by_path[abs] and Watcher.is_fs_event_capable(abs) then
+    local filter_reason = parent.filters:should_filter_as_reason(abs, stat, filter_status)
+    if filter_reason == FILTER_REASON.none 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, stat)
@@ -47,6 +58,12 @@ local function populate_children(handle, cwd, node, git_status, parent)
         nodes_by_path[child.absolute_path] = true
         explorer_node.update_git_status(child, node_ignored, git_status)
       end
+    else
+      for reason, value in pairs(FILTER_REASON) do
+        if filter_reason == value then
+          node.hidden_stats[reason] = node.hidden_stats[reason] + 1
+        end
+      end
     end
 
     log.profile_end(profile)

lua/nvim-tree/explorer/filters.lua

@@ -1,4 +1,5 @@
 local utils = require "nvim-tree.utils"
+local FILTER_REASON = require("nvim-tree.enum").FILTER_REASON
 
 ---@class Filters to handle all opts.filters and related API
 ---@field config table hydrated user opts.filters
@@ -223,4 +224,33 @@ function Filters:should_filter(path, fs_stat, status)
     or bookmark(self, path, fs_stat and fs_stat.type, status.bookmarks)
 end
 
+--- Check if the given path should be filtered, and provide the reason why it was
+---@param path string Absolute path
+---@param fs_stat uv.fs_stat.result|nil fs_stat of file
+---@param status table from prepare
+---@return FILTER_REASON
+function Filters:should_filter_as_reason(path, fs_stat, status)
+  if not self.config.enable then
+    return FILTER_REASON.none
+  end
+
+  if is_excluded(self, path) then
+    return FILTER_REASON.none
+  end
+
+  if git(self, path, status.git_status) then
+    return FILTER_REASON.git
+  elseif buf(self, path, status.bufinfo) then
+    return FILTER_REASON.buf
+  elseif dotfile(self, path) then
+    return FILTER_REASON.dotfile
+  elseif custom(self, path) then
+    return FILTER_REASON.custom
+  elseif bookmark(self, path, fs_stat and fs_stat.type, status.bookmarks) then
+    return FILTER_REASON.bookmark
+  else
+    return FILTER_REASON.none
+  end
+end
+
 return Filters

lua/nvim-tree/explorer/reload.lua

@@ -5,6 +5,7 @@ local live_filter = require "nvim-tree.live-filter"
 local git = require "nvim-tree.git"
 local log = require "nvim-tree.log"
 
+local FILTER_REASON = require("nvim-tree.enum").FILTER_REASON
 local NodeIterator = require "nvim-tree.iterators.node-iterator"
 local Watcher = require "nvim-tree.watcher"
 
@@ -92,6 +93,16 @@ function M.reload(node, git_status)
   local node_ignored = explorer_node.is_git_ignored(node)
   ---@type table<string, Node>
   local nodes_by_path = utils.key_by(node.nodes, "absolute_path")
+
+  -- To reset we must 'zero' everything that we use
+  node.hidden_stats = vim.tbl_deep_extend("force", node.hidden_stats or {}, {
+    git = 0,
+    buf = 0,
+    dotfile = 0,
+    custom = 0,
+    bookmark = 0,
+  })
+
   while true do
     local name, t = vim.loop.fs_scandir_next(handle)
     if not name then
@@ -102,7 +113,8 @@ function M.reload(node, git_status)
     ---@type uv.fs_stat.result|nil
     local stat = vim.loop.fs_stat(abs)
 
-    if not explorer.filters:should_filter(abs, stat, filter_status) then
+    local filter_reason = explorer.filters:should_filter_as_reason(abs, stat, filter_status)
+    if filter_reason == FILTER_REASON.none then
       remain_childs[abs] = true
 
       -- Recreate node if type changes.
@@ -139,6 +151,12 @@ function M.reload(node, git_status)
           n.fs_stat = stat
         end
       end
+    else
+      for reason, value in pairs(FILTER_REASON) do
+        if filter_reason == value then
+          node.hidden_stats[reason] = node.hidden_stats[reason] + 1
+        end
+      end
     end
   end