feat: add renderer.highlight_hidden, renderer.icons.show.hidden and renderer.icons.hidden_placement for dotfile icons/highlights (#2840)

* feat(hidden_decorator): Allow hidden (dotfiles) to be highlighted, both icon and name (this not related to git highlights).

Better defaults

squashed

docs(hidden)

docs(hidden)

docs(hidden)

* fix(typo): small typo on hl groups

* feat(hidden_dotfile_highlight): make a file that has a dotfile parent be also a dotfile

* docs: update docs on hidden highlight

---------

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

lua/nvim-tree/appearance/init.lua

@@ -76,6 +76,11 @@ M.HIGHLIGHT_GROUPS = {
   { group = "NvimTreeModifiedFileHL", link = "NvimTreeModifiedIcon" },
   { group = "NvimTreeModifiedFolderHL", link = "NvimTreeModifiedFileHL" },
 
+  -- Hidden
+  { group = "NvimTreeHiddenIcon", link = "Conceal" },
+  { group = "NvimTreeHiddenFileHL", link = "NvimTreeHiddenIcon" },
+  { group = "NvimTreeHiddenFolderHL", link = "NvimTreeHiddenFileHL" },
+
   -- Opened
   { group = "NvimTreeOpenedHL", link = "Special" },
 

lua/nvim-tree/explorer/node.lua

@@ -128,6 +128,19 @@ function M.is_git_ignored(node)
   return node and node.git_status ~= nil and node.git_status.file == "!!"
 end
 
+---@param node Node
+---@return boolean
+function M.is_dotfile(node)
+  if node == nil then
+    return false
+  end
+  if node.is_dot or (node.name and (node.name:sub(1, 1) == ".")) or M.is_dotfile(node.parent) then
+    node.is_dot = true
+    return true
+  end
+  return false
+end
+
 ---@param node Node
 function M.node_destroy(node)
   if not node then

lua/nvim-tree/node.lua

@@ -9,6 +9,7 @@
 ---@field fs_stat uv.fs_stat.result|nil
 ---@field git_status GitStatus|nil
 ---@field hidden boolean
+---@field is_dot boolean
 ---@field name string
 ---@field parent DirNode
 ---@field type string

lua/nvim-tree/renderer/builder.lua

@@ -10,6 +10,7 @@ local DecoratorCut = require "nvim-tree.renderer.decorator.cut"
 local DecoratorDiagnostics = require "nvim-tree.renderer.decorator.diagnostics"
 local DecoratorGit = require "nvim-tree.renderer.decorator.git"
 local DecoratorModified = require "nvim-tree.renderer.decorator.modified"
+local DecoratorHidden = require "nvim-tree.renderer.decorator.hidden"
 local DecoratorOpened = require "nvim-tree.renderer.decorator.opened"
 
 local pad = require "nvim-tree.renderer.components.padding"
@@ -442,6 +443,7 @@ function Builder.setup(opts)
     DecoratorDiagnostics:new(opts),
     DecoratorBookmarks:new(opts),
     DecoratorModified:new(opts),
+    DecoratorHidden:new(opts),
     DecoratorOpened:new(opts),
     DecoratorGit:new(opts),
   }

lua/nvim-tree/renderer/decorator/hidden.lua

@@ -0,0 +1,55 @@
+local HL_POSITION = require("nvim-tree.enum").HL_POSITION
+local ICON_PLACEMENT = require("nvim-tree.enum").ICON_PLACEMENT
+local explorer_node = require "nvim-tree.explorer.node"
+local Decorator = require "nvim-tree.renderer.decorator"
+
+---@class DecoratorHidden: Decorator
+---@field icon HighlightedString|nil
+local DecoratorHidden = Decorator:new()
+
+---@param opts table
+---@return DecoratorHidden
+function DecoratorHidden:new(opts)
+  local o = Decorator.new(self, {
+    enabled = true,
+    hl_pos = HL_POSITION[opts.renderer.highlight_hidden] or HL_POSITION.none,
+    icon_placement = ICON_PLACEMENT[opts.renderer.icons.hidden_placement] or ICON_PLACEMENT.none,
+  })
+  ---@cast o DecoratorHidden
+
+  if opts.renderer.icons.show.hidden then
+    o.icon = {
+      str = opts.renderer.icons.glyphs.hidden,
+      hl = { "NvimTreeHiddenIcon" },
+    }
+    o:define_sign(o.icon)
+  end
+
+  return o
+end
+
+---Hidden icon: hidden.enable, renderer.icons.show.hidden and node starts with `.` (dotfile).
+---@param node Node
+---@return HighlightedString[]|nil icons
+function DecoratorHidden:calculate_icons(node)
+  if self.enabled and explorer_node.is_dotfile(node) then
+    return { self.icon }
+  end
+end
+
+---Hidden highlight: hidden.enable, renderer.highlight_hidden and node starts with `.` (dotfile).
+---@param node Node
+---@return string|nil group
+function DecoratorHidden:calculate_highlight(node)
+  if not self.enabled or self.hl_pos == HL_POSITION.none or (not explorer_node.is_dotfile(node)) then
+    return nil
+  end
+
+  if node.nodes then
+    return "NvimTreeHiddenFolderHL"
+  else
+    return "NvimTreeHiddenFileHL"
+  end
+end
+
+return DecoratorHidden