feat(#2415): add :NvimTreeHiTest (#2664)

* feat(#2415): add :NvimTreeHiTest

* feat(#2415): split out appearance diagnostics

doc/nvim-tree-lua.txt

@@ -10,6 +10,7 @@ CONTENTS                                                           *nvim-tree*
   2.1  Quickstart: Setup                        |nvim-tree-quickstart-setup|
   2.2  Quickstart: Help                         |nvim-tree-quickstart-help|
   2.3  Quickstart: Custom Mappings              |nvim-tree-quickstart-custom-mappings|
+  2.4  Quickstart: Highlight                    |nvim-tree-quickstart-highlight|
   3. Commands                                 |nvim-tree-commands|
   4. Setup                                    |nvim-tree-setup|
   5. Opts                                     |nvim-tree-opts|
@@ -43,6 +44,7 @@ CONTENTS                                                           *nvim-tree*
   6.7  API Marks                                |nvim-tree-api.marks|
   6.8  API Config                               |nvim-tree-api.config|
   6.9  API Commands                             |nvim-tree-api.commands|
+  6.10 API Diagnostics                          |nvim-tree-api.diagnostics|
   7. Mappings                                 |nvim-tree-mappings|
   7.1  Mappings: Default                        |nvim-tree-mappings-default|
   8. Highlight                                |nvim-tree-highlight|
@@ -230,6 +232,16 @@ via |nvim-tree.on_attach| e.g. >
     ---
   }
 <
+==============================================================================
+ 2.4 QUICKSTART: HIGHLIGHT                    *nvim-tree-quickstart-highlight*
+
+Run |:NvimTreeHiTest| to show all the highlights that nvim-tree uses.
+
+They can be customised before or after setup is called and will be immediately
+applied at runtime.
+
+See |nvim-tree-highlight| for details.
+
 ==============================================================================
  3. COMMANDS                                              *nvim-tree-commands*
 
@@ -324,6 +336,14 @@ via |nvim-tree.on_attach| e.g. >
 
     Calls: `api.tree.collapse_all(true)`
 
+*:NvimTreeHiTest*
+
+    Show nvim-tree highlight groups similar to `:so $VIMRUNTIME/syntax/hitest.vim`
+
+    See |nvim-tree-api.diagnostics.hi_test()|
+
+    Calls: `api.diagnostics.hi_test()`
+
 ==============================================================================
  4. SETUP                                                    *nvim-tree-setup*
 
@@ -2077,7 +2097,7 @@ config.mappings.get_keymap_default()
         (table) as per |nvim_buf_get_keymap()|
 
 ==============================================================================
- 6.8 API COMMANDS                                     *nvim-tree-api.commands*
+ 6.9 API COMMANDS                                     *nvim-tree-api.commands*
 
 commands.get()                                  *nvim-tree-api.commands.get()*
     Retrieve all commands, see |nvim-tree-commands|
@@ -2088,6 +2108,15 @@ commands.get()                                  *nvim-tree-api.commands.get()*
         • {command} (function)
         • {opts}    (table)
 
+==============================================================================
+ 6.10 DIAGNOSTICS                                  *nvim-tree-api.diagnostics*
+
+diagnostics.hi_test()                    *nvim-tree-api.diagnostics.hi_test()*
+    Open a new buffer displaying all nvim-tree highlight groups, their link
+    chain and concrete definition.
+
+    Similar to `:so $VIMRUNTIME/syntax/hitest.vim` as per |:highlight|
+
 ==============================================================================
  7. MAPPINGS                                              *nvim-tree-mappings*
 
@@ -2253,7 +2282,9 @@ Example |:highlight| >
 It is recommended to enable 'termguicolors' for the more pleasant 24-bit
 colours.
 
-To view the active highlight groups run `:so $VIMRUNTIME/syntax/hitest.vim`
+To view the nvim-tree highlight groups run |:NvimTreeHiTest|
+
+To view all active highlight groups run `:so $VIMRUNTIME/syntax/hitest.vim`
 as per |:highlight|
 
 The `*HL` groups are additive as per |nvim-tree-opts-renderer| precedence.

lua/nvim-tree/api.lua

@@ -2,6 +2,7 @@ local lib = require "nvim-tree.lib"
 local view = require "nvim-tree.view"
 local utils = require "nvim-tree.utils"
 local actions = require "nvim-tree.actions"
+local appearance_diagnostics = require "nvim-tree.appearance.diagnostics"
 local events = require "nvim-tree.events"
 local help = require "nvim-tree.help"
 local live_filter = require "nvim-tree.live-filter"
@@ -39,6 +40,7 @@ local Api = {
     mappings = {},
   },
   commands = {},
+  diagnostics = {},
 }
 
 --- Do nothing when setup not called.
@@ -245,6 +247,8 @@ Api.config.mappings.get_keymap = wrap(keymap.get_keymap)
 Api.config.mappings.get_keymap_default = wrap(keymap.get_keymap_default)
 Api.config.mappings.default_on_attach = keymap.default_on_attach
 
+Api.diagnostics.hi_test = wrap(appearance_diagnostics.hi_test)
+
 Api.commands.get = wrap(function()
   return require("nvim-tree.commands").get()
 end)

lua/nvim-tree/appearance.lua

@@ -1,199 +0,0 @@
-local M = {}
-
--- directly defined groups, please keep these to an absolute minimum
-local DEFAULT_DEFS = {
-
-  NvimTreeFolderIcon = "guifg=#8094b4 ctermfg=Blue",
-  NvimTreeWindowPicker = "guifg=#ededed guibg=#4493c8 gui=bold ctermfg=White ctermbg=Cyan",
-}
-
--- nvim-tree default highlight group links, please attempt to keep in order with help
-local DEFAULT_LINKS = {
-
-  -- Standard
-  NvimTreeNormal = "Normal",
-  NvimTreeNormalFloat = "NormalFloat",
-  NvimTreeNormalNC = "NvimTreeNormal",
-
-  NvimTreeLineNr = "LineNr",
-  NvimTreeWinSeparator = "WinSeparator",
-  NvimTreeEndOfBuffer = "EndOfBuffer",
-  NvimTreePopup = "Normal",
-  NvimTreeSignColumn = "NvimTreeNormal",
-
-  NvimTreeCursorColumn = "CursorColumn",
-  NvimTreeCursorLine = "CursorLine",
-  NvimTreeCursorLineNr = "CursorLineNr",
-
-  NvimTreeStatusLine = "StatusLine",
-  NvimTreeStatusLineNC = "StatusLineNC",
-
-  -- File Text
-  NvimTreeExecFile = "SpellCap",
-  NvimTreeImageFile = "SpellCap",
-  NvimTreeSpecialFile = "SpellCap",
-  NvimTreeSymlink = "SpellCap",
-
-  -- Folder Text
-  NvimTreeRootFolder = "Title",
-  NvimTreeFolderName = "Directory",
-  NvimTreeEmptyFolderName = "Directory",
-  NvimTreeOpenedFolderName = "Directory",
-  NvimTreeSymlinkFolderName = "Directory",
-
-  -- File Icons
-  NvimTreeFileIcon = "NvimTreeNormal",
-  NvimTreeSymlinkIcon = "NvimTreeNormal",
-
-  -- Folder Icons
-  NvimTreeOpenedFolderIcon = "NvimTreeFolderIcon",
-  NvimTreeClosedFolderIcon = "NvimTreeFolderIcon",
-  NvimTreeFolderArrowClosed = "NvimTreeIndentMarker",
-  NvimTreeFolderArrowOpen = "NvimTreeIndentMarker",
-
-  -- Indent
-  NvimTreeIndentMarker = "NvimTreeFolderIcon",
-
-  -- LiveFilter
-  NvimTreeLiveFilterPrefix = "PreProc",
-  NvimTreeLiveFilterValue = "ModeMsg",
-
-  -- Clipboard
-  NvimTreeCutHL = "SpellBad",
-  NvimTreeCopiedHL = "SpellRare",
-
-  -- Bookmark
-  NvimTreeBookmarkIcon = "NvimTreeFolderIcon",
-  NvimTreeBookmarkHL = "SpellLocal",
-
-  -- Modified
-  NvimTreeModifiedIcon = "Type",
-  NvimTreeModifiedFileHL = "NvimTreeModifiedIcon",
-  NvimTreeModifiedFolderHL = "NvimTreeModifiedFileHL",
-
-  -- Opened
-  NvimTreeOpenedHL = "Special",
-
-  -- Git Icon
-  NvimTreeGitDeletedIcon = "Statement",
-  NvimTreeGitDirtyIcon = "Statement",
-  NvimTreeGitIgnoredIcon = "Comment",
-  NvimTreeGitMergeIcon = "Constant",
-  NvimTreeGitNewIcon = "PreProc",
-  NvimTreeGitRenamedIcon = "PreProc",
-  NvimTreeGitStagedIcon = "Constant",
-
-  -- Git File Highlight
-  NvimTreeGitFileDeletedHL = "NvimTreeGitDeletedIcon",
-  NvimTreeGitFileDirtyHL = "NvimTreeGitDirtyIcon",
-  NvimTreeGitFileIgnoredHL = "NvimTreeGitIgnoredIcon",
-  NvimTreeGitFileMergeHL = "NvimTreeGitMergeIcon",
-  NvimTreeGitFileNewHL = "NvimTreeGitNewIcon",
-  NvimTreeGitFileRenamedHL = "NvimTreeGitRenamedIcon",
-  NvimTreeGitFileStagedHL = "NvimTreeGitStagedIcon",
-
-  -- Git Folder Highlight
-  NvimTreeGitFolderDeletedHL = "NvimTreeGitFileDeletedHL",
-  NvimTreeGitFolderDirtyHL = "NvimTreeGitFileDirtyHL",
-  NvimTreeGitFolderIgnoredHL = "NvimTreeGitFileIgnoredHL",
-  NvimTreeGitFolderMergeHL = "NvimTreeGitFileMergeHL",
-  NvimTreeGitFolderNewHL = "NvimTreeGitFileNewHL",
-  NvimTreeGitFolderRenamedHL = "NvimTreeGitFileRenamedHL",
-  NvimTreeGitFolderStagedHL = "NvimTreeGitFileStagedHL",
-
-  -- Diagnostics Icon
-  NvimTreeDiagnosticErrorIcon = "DiagnosticError",
-  NvimTreeDiagnosticWarnIcon = "DiagnosticWarn",
-  NvimTreeDiagnosticInfoIcon = "DiagnosticInfo",
-  NvimTreeDiagnosticHintIcon = "DiagnosticHint",
-
-  -- Diagnostics File Highlight
-  NvimTreeDiagnosticErrorFileHL = "DiagnosticUnderlineError",
-  NvimTreeDiagnosticWarnFileHL = "DiagnosticUnderlineWarn",
-  NvimTreeDiagnosticInfoFileHL = "DiagnosticUnderlineInfo",
-  NvimTreeDiagnosticHintFileHL = "DiagnosticUnderlineHint",
-
-  -- Diagnostics Folder Highlight
-  NvimTreeDiagnosticErrorFolderHL = "NvimTreeDiagnosticErrorFileHL",
-  NvimTreeDiagnosticWarnFolderHL = "NvimTreeDiagnosticWarnFileHL",
-  NvimTreeDiagnosticInfoFolderHL = "NvimTreeDiagnosticInfoFileHL",
-  NvimTreeDiagnosticHintFolderHL = "NvimTreeDiagnosticHintFileHL",
-}
-
--- nvim-tree highlight groups to legacy
-local LEGACY_LINKS = {
-  NvimTreeModifiedIcon = "NvimTreeModifiedFile",
-
-  NvimTreeOpenedHL = "NvimTreeOpenedFile",
-
-  NvimTreeBookmarkIcon = "NvimTreeBookmark",
-
-  NvimTreeGitDeletedIcon = "NvimTreeGitDeleted",
-  NvimTreeGitDirtyIcon = "NvimTreeGitDirty",
-  NvimTreeGitIgnoredIcon = "NvimTreeGitIgnored",
-  NvimTreeGitMergeIcon = "NvimTreeGitMerge",
-  NvimTreeGitNewIcon = "NvimTreeGitNew",
-  NvimTreeGitRenamedIcon = "NvimTreeGitRenamed",
-  NvimTreeGitStagedIcon = "NvimTreeGitStaged",
-
-  NvimTreeGitFileDeletedHL = "NvimTreeFileDeleted",
-  NvimTreeGitFileDirtyHL = "NvimTreeFileDirty",
-  NvimTreeGitFileIgnoredHL = "NvimTreeFileIgnored",
-  NvimTreeGitFileMergeHL = "NvimTreeFileMerge",
-  NvimTreeGitFileNewHL = "NvimTreeFileNew",
-  NvimTreeGitFileRenamedHL = "NvimTreeFileRenamed",
-  NvimTreeGitFileStagedHL = "NvimTreeFileStaged",
-
-  NvimTreeGitFolderDeletedHL = "NvimTreeFolderDeleted",
-  NvimTreeGitFolderDirtyHL = "NvimTreeFolderDirty",
-  NvimTreeGitFolderIgnoredHL = "NvimTreeFolderIgnored",
-  NvimTreeGitFolderMergeHL = "NvimTreeFolderMerge",
-  NvimTreeGitFolderNewHL = "NvimTreeFolderNew",
-  NvimTreeGitFolderRenamedHL = "NvimTreeFolderRenamed",
-  NvimTreeGitFolderStagedHL = "NvimTreeFolderStaged",
-
-  NvimTreeDiagnosticErrorIcon = "NvimTreeLspDiagnosticsError",
-  NvimTreeDiagnosticWarnIcon = "NvimTreeLspDiagnosticsWarning",
-  NvimTreeDiagnosticInfoIcon = "NvimTreeLspDiagnosticsInformation",
-  NvimTreeDiagnosticHintIcon = "NvimTreeLspDiagnosticsHint",
-
-  NvimTreeDiagnosticErrorFileHL = "NvimTreeLspDiagnosticsErrorText",
-  NvimTreeDiagnosticWarnFileHL = "NvimTreeLspDiagnosticsWarningText",
-  NvimTreeDiagnosticInfoFileHL = "NvimTreeLspDiagnosticsInformationText",
-  NvimTreeDiagnosticHintFileHL = "NvimTreeLspDiagnosticsHintText",
-
-  NvimTreeDiagnosticErrorFolderHL = "NvimTreeLspDiagnosticsErrorFolderText",
-  NvimTreeDiagnosticWarnFolderHL = "NvimTreeLspDiagnosticsWarningFolderText",
-  NvimTreeDiagnosticInfoFolderHL = "NvimTreeLspDiagnosticsInformationFolderText",
-  NvimTreeDiagnosticHintFolderHL = "NvimTreeLspDiagnosticsHintFolderText",
-}
-
-function M.setup()
-  -- non-linked
-  for k, d in pairs(DEFAULT_DEFS) do
-    vim.api.nvim_command("hi def " .. k .. " " .. d)
-  end
-
-  -- hard link override when legacy only is present
-  for from, to in pairs(LEGACY_LINKS) do
-    local hl_from
-    local hl_to
-    if vim.fn.has "nvim-0.9" == 1 then
-      hl_from = vim.api.nvim_get_hl(0, { name = from })
-      hl_to = vim.api.nvim_get_hl(0, { name = to })
-    else
-      hl_from = vim.api.nvim__get_hl_defs(0)[from] or {}
-      hl_to = vim.api.nvim__get_hl_defs(0)[to] or {}
-    end
-    if vim.tbl_isempty(hl_from) and not vim.tbl_isempty(hl_to) then
-      vim.api.nvim_command("hi link " .. from .. " " .. to)
-    end
-  end
-
-  -- default links
-  for from, to in pairs(DEFAULT_LINKS) do
-    vim.api.nvim_command("hi def link " .. from .. " " .. to)
-  end
-end
-
-return M

lua/nvim-tree/appearance/diagnostics.lua

@@ -0,0 +1,80 @@
+local appearance = require "nvim-tree.appearance"
+
+local M = {}
+
+---@class HighlightDisplay for :NvimTreeHiTest
+---@field group string nvim-tree highlight group name
+---@field links string link chain to a concretely defined group
+---@field def string :hi concrete definition after following any links
+local HighlightDisplay = {}
+
+---@param group string nvim-tree highlight group
+---@return HighlightDisplay
+function HighlightDisplay:new(group)
+  local o = {}
+  setmetatable(o, self)
+  self.__index = self
+
+  o.group = group
+  local concrete = o.group
+
+  -- maybe follow links
+  local links = {}
+  local link = vim.api.nvim_get_hl(0, { name = o.group }).link
+  while link do
+    table.insert(links, link)
+    concrete = link
+    link = vim.api.nvim_get_hl(0, { name = link }).link
+  end
+  o.links = table.concat(links, " ")
+
+  -- concrete definition
+  local ok, res = pcall(vim.api.nvim_cmd, { cmd = "highlight", args = { concrete } }, { output = true })
+  if ok and type(res) == "string" then
+    o.def = res:gsub(".*xxx *", "")
+  else
+    o.def = ""
+  end
+
+  return o
+end
+
+function HighlightDisplay:render(bufnr, fmt, l)
+  local text = string.format(fmt, self.group, self.links, self.def)
+
+  vim.api.nvim_buf_set_lines(bufnr, l, -1, true, { text })
+  vim.api.nvim_buf_add_highlight(bufnr, -1, self.group, l, 0, #self.group)
+end
+
+---Run a test similar to :so $VIMRUNTIME/syntax/hitest.vim
+---Display all nvim-tree highlight groups, their link chain and actual definition
+function M.hi_test()
+  local displays = {}
+  local max_group_len = 0
+  local max_links_len = 0
+
+  -- build all highlight groups, name only
+  for _, highlight_group in ipairs(appearance.HIGHLIGHT_GROUPS) do
+    local display = HighlightDisplay:new(highlight_group.group)
+    table.insert(displays, display)
+    max_group_len = math.max(max_group_len, #display.group)
+    max_links_len = math.max(max_links_len, #display.links)
+  end
+
+  -- create a buffer
+  local bufnr = vim.api.nvim_create_buf(false, true)
+
+  -- render and highlight
+  local l = 0
+  local fmt = string.format("%%-%d.%ds %%-%d.%ds %%s", max_group_len, max_group_len, max_links_len, max_links_len)
+  for _, display in ipairs(displays) do
+    display:render(bufnr, fmt, l)
+    l = l + 1
+  end
+
+  -- finalise and focus the buffer
+  vim.api.nvim_buf_set_option(bufnr, "modifiable", false)
+  vim.cmd.buffer(bufnr)
+end
+
+return M

lua/nvim-tree/appearance/init.lua

@@ -0,0 +1,202 @@
+local M = {}
+
+-- All highlight groups: linked or directly defined.
+-- Please add new groups to help and preserve order.
+-- Please avoid directly defined groups to preserve accessibility for TUI.
+M.HIGHLIGHT_GROUPS = {
+
+  -- Standard
+  { group = "NvimTreeNormal", link = "Normal" },
+  { group = "NvimTreeNormalFloat", link = "NormalFloat" },
+  { group = "NvimTreeNormalNC", link = "NvimTreeNormal" },
+
+  { group = "NvimTreeLineNr", link = "LineNr" },
+  { group = "NvimTreeWinSeparator", link = "WinSeparator" },
+  { group = "NvimTreeEndOfBuffer", link = "EndOfBuffer" },
+  { group = "NvimTreePopup", link = "Normal" },
+  { group = "NvimTreeSignColumn", link = "NvimTreeNormal" },
+
+  { group = "NvimTreeCursorColumn", link = "CursorColumn" },
+  { group = "NvimTreeCursorLine", link = "CursorLine" },
+  { group = "NvimTreeCursorLineNr", link = "CursorLineNr" },
+
+  { group = "NvimTreeStatusLine", link = "StatusLine" },
+  { group = "NvimTreeStatusLineNC", link = "StatusLineNC" },
+
+  -- File Text
+  { group = "NvimTreeExecFile", link = "SpellCap" },
+  { group = "NvimTreeImageFile", link = "SpellCap" },
+  { group = "NvimTreeSpecialFile", link = "SpellCap" },
+  { group = "NvimTreeSymlink", link = "SpellCap" },
+
+  -- Folder Text
+  { group = "NvimTreeRootFolder", link = "Title" },
+  { group = "NvimTreeFolderName", link = "Directory" },
+  { group = "NvimTreeEmptyFolderName", link = "Directory" },
+  { group = "NvimTreeOpenedFolderName", link = "Directory" },
+  { group = "NvimTreeSymlinkFolderName", link = "Directory" },
+
+  -- File Icons
+  { group = "NvimTreeFileIcon", link = "NvimTreeNormal" },
+  { group = "NvimTreeSymlinkIcon", link = "NvimTreeNormal" },
+
+  -- Folder Icons
+  { group = "NvimTreeFolderIcon", def = "guifg=#8094b4 ctermfg=Blue" },
+  { group = "NvimTreeOpenedFolderIcon", link = "NvimTreeFolderIcon" },
+  { group = "NvimTreeClosedFolderIcon", link = "NvimTreeFolderIcon" },
+  { group = "NvimTreeFolderArrowClosed", link = "NvimTreeIndentMarker" },
+  { group = "NvimTreeFolderArrowOpen", link = "NvimTreeIndentMarker" },
+
+  -- Indent
+  { group = "NvimTreeIndentMarker", link = "NvimTreeFolderIcon" },
+
+  -- Picker
+  { group = "NvimTreeWindowPicker", def = "guifg=#ededed guibg=#4493c8 gui=bold ctermfg=White ctermbg=Cyan" },
+
+  -- LiveFilter
+  { group = "NvimTreeLiveFilterPrefix", link = "PreProc" },
+  { group = "NvimTreeLiveFilterValue", link = "ModeMsg" },
+
+  -- Clipboard
+  { group = "NvimTreeCutHL", link = "SpellBad" },
+  { group = "NvimTreeCopiedHL", link = "SpellRare" },
+
+  -- Bookmark
+  { group = "NvimTreeBookmarkIcon", link = "NvimTreeFolderIcon" },
+  { group = "NvimTreeBookmarkHL", link = "SpellLocal" },
+
+  -- Modified
+  { group = "NvimTreeModifiedIcon", link = "Type" },
+  { group = "NvimTreeModifiedFileHL", link = "NvimTreeModifiedIcon" },
+  { group = "NvimTreeModifiedFolderHL", link = "NvimTreeModifiedFileHL" },
+
+  -- Opened
+  { group = "NvimTreeOpenedHL", link = "Special" },
+
+  -- Git Icon
+  { group = "NvimTreeGitDeletedIcon", link = "Statement" },
+  { group = "NvimTreeGitDirtyIcon", link = "Statement" },
+  { group = "NvimTreeGitIgnoredIcon", link = "Comment" },
+  { group = "NvimTreeGitMergeIcon", link = "Constant" },
+  { group = "NvimTreeGitNewIcon", link = "PreProc" },
+  { group = "NvimTreeGitRenamedIcon", link = "PreProc" },
+  { group = "NvimTreeGitStagedIcon", link = "Constant" },
+
+  -- Git File Highlight
+  { group = "NvimTreeGitFileDeletedHL", link = "NvimTreeGitDeletedIcon" },
+  { group = "NvimTreeGitFileDirtyHL", link = "NvimTreeGitDirtyIcon" },
+  { group = "NvimTreeGitFileIgnoredHL", link = "NvimTreeGitIgnoredIcon" },
+  { group = "NvimTreeGitFileMergeHL", link = "NvimTreeGitMergeIcon" },
+  { group = "NvimTreeGitFileNewHL", link = "NvimTreeGitNewIcon" },
+  { group = "NvimTreeGitFileRenamedHL", link = "NvimTreeGitRenamedIcon" },
+  { group = "NvimTreeGitFileStagedHL", link = "NvimTreeGitStagedIcon" },
+
+  -- Git Folder Highlight
+  { group = "NvimTreeGitFolderDeletedHL", link = "NvimTreeGitFileDeletedHL" },
+  { group = "NvimTreeGitFolderDirtyHL", link = "NvimTreeGitFileDirtyHL" },
+  { group = "NvimTreeGitFolderIgnoredHL", link = "NvimTreeGitFileIgnoredHL" },
+  { group = "NvimTreeGitFolderMergeHL", link = "NvimTreeGitFileMergeHL" },
+  { group = "NvimTreeGitFolderNewHL", link = "NvimTreeGitFileNewHL" },
+  { group = "NvimTreeGitFolderRenamedHL", link = "NvimTreeGitFileRenamedHL" },
+  { group = "NvimTreeGitFolderStagedHL", link = "NvimTreeGitFileStagedHL" },
+
+  -- Diagnostics Icon
+  { group = "NvimTreeDiagnosticErrorIcon", link = "DiagnosticError" },
+  { group = "NvimTreeDiagnosticWarnIcon", link = "DiagnosticWarn" },
+  { group = "NvimTreeDiagnosticInfoIcon", link = "DiagnosticInfo" },
+  { group = "NvimTreeDiagnosticHintIcon", link = "DiagnosticHint" },
+
+  -- Diagnostics File Highlight
+  { group = "NvimTreeDiagnosticErrorFileHL", link = "DiagnosticUnderlineError" },
+  { group = "NvimTreeDiagnosticWarnFileHL", link = "DiagnosticUnderlineWarn" },
+  { group = "NvimTreeDiagnosticInfoFileHL", link = "DiagnosticUnderlineInfo" },
+  { group = "NvimTreeDiagnosticHintFileHL", link = "DiagnosticUnderlineHint" },
+
+  -- Diagnostics Folder Highlight
+  { group = "NvimTreeDiagnosticErrorFolderHL", link = "NvimTreeDiagnosticErrorFileHL" },
+  { group = "NvimTreeDiagnosticWarnFolderHL", link = "NvimTreeDiagnosticWarnFileHL" },
+  { group = "NvimTreeDiagnosticInfoFolderHL", link = "NvimTreeDiagnosticInfoFileHL" },
+  { group = "NvimTreeDiagnosticHintFolderHL", link = "NvimTreeDiagnosticHintFileHL" },
+}
+
+-- nvim-tree highlight groups to legacy
+M.LEGACY_LINKS = {
+  NvimTreeModifiedIcon = "NvimTreeModifiedFile",
+
+  NvimTreeOpenedHL = "NvimTreeOpenedFile",
+
+  NvimTreeBookmarkIcon = "NvimTreeBookmark",
+
+  NvimTreeGitDeletedIcon = "NvimTreeGitDeleted",
+  NvimTreeGitDirtyIcon = "NvimTreeGitDirty",
+  NvimTreeGitIgnoredIcon = "NvimTreeGitIgnored",
+  NvimTreeGitMergeIcon = "NvimTreeGitMerge",
+  NvimTreeGitNewIcon = "NvimTreeGitNew",
+  NvimTreeGitRenamedIcon = "NvimTreeGitRenamed",
+  NvimTreeGitStagedIcon = "NvimTreeGitStaged",
+
+  NvimTreeGitFileDeletedHL = "NvimTreeFileDeleted",
+  NvimTreeGitFileDirtyHL = "NvimTreeFileDirty",
+  NvimTreeGitFileIgnoredHL = "NvimTreeFileIgnored",
+  NvimTreeGitFileMergeHL = "NvimTreeFileMerge",
+  NvimTreeGitFileNewHL = "NvimTreeFileNew",
+  NvimTreeGitFileRenamedHL = "NvimTreeFileRenamed",
+  NvimTreeGitFileStagedHL = "NvimTreeFileStaged",
+
+  NvimTreeGitFolderDeletedHL = "NvimTreeFolderDeleted",
+  NvimTreeGitFolderDirtyHL = "NvimTreeFolderDirty",
+  NvimTreeGitFolderIgnoredHL = "NvimTreeFolderIgnored",
+  NvimTreeGitFolderMergeHL = "NvimTreeFolderMerge",
+  NvimTreeGitFolderNewHL = "NvimTreeFolderNew",
+  NvimTreeGitFolderRenamedHL = "NvimTreeFolderRenamed",
+  NvimTreeGitFolderStagedHL = "NvimTreeFolderStaged",
+
+  NvimTreeDiagnosticErrorIcon = "NvimTreeLspDiagnosticsError",
+  NvimTreeDiagnosticWarnIcon = "NvimTreeLspDiagnosticsWarning",
+  NvimTreeDiagnosticInfoIcon = "NvimTreeLspDiagnosticsInformation",
+  NvimTreeDiagnosticHintIcon = "NvimTreeLspDiagnosticsHint",
+
+  NvimTreeDiagnosticErrorFileHL = "NvimTreeLspDiagnosticsErrorText",
+  NvimTreeDiagnosticWarnFileHL = "NvimTreeLspDiagnosticsWarningText",
+  NvimTreeDiagnosticInfoFileHL = "NvimTreeLspDiagnosticsInformationText",
+  NvimTreeDiagnosticHintFileHL = "NvimTreeLspDiagnosticsHintText",
+
+  NvimTreeDiagnosticErrorFolderHL = "NvimTreeLspDiagnosticsErrorFolderText",
+  NvimTreeDiagnosticWarnFolderHL = "NvimTreeLspDiagnosticsWarningFolderText",
+  NvimTreeDiagnosticInfoFolderHL = "NvimTreeLspDiagnosticsInformationFolderText",
+  NvimTreeDiagnosticHintFolderHL = "NvimTreeLspDiagnosticsHintFolderText",
+}
+
+function M.setup()
+  -- non-linked
+  for _, g in ipairs(M.HIGHLIGHT_GROUPS) do
+    if g.def then
+      vim.api.nvim_command("hi def " .. g.group .. " " .. g.def)
+    end
+  end
+
+  -- hard link override when legacy only is present
+  for from, to in pairs(M.LEGACY_LINKS) do
+    local hl_from
+    local hl_to
+    if vim.fn.has "nvim-0.9" == 1 then
+      hl_from = vim.api.nvim_get_hl(0, { name = from })
+      hl_to = vim.api.nvim_get_hl(0, { name = to })
+    else
+      hl_from = vim.api.nvim__get_hl_defs(0)[from] or {}
+      hl_to = vim.api.nvim__get_hl_defs(0)[to] or {}
+    end
+    if vim.tbl_isempty(hl_from) and not vim.tbl_isempty(hl_to) then
+      vim.api.nvim_command("hi link " .. from .. " " .. to)
+    end
+  end
+
+  -- default links
+  for _, g in ipairs(M.HIGHLIGHT_GROUPS) do
+    if g.link then
+      vim.api.nvim_command("hi def link " .. g.group .. " " .. g.link)
+    end
+  end
+end
+
+return M

lua/nvim-tree/commands.lua

@@ -134,6 +134,13 @@ local CMDS = {
       api.tree.collapse_all(true)
     end,
   },
+  {
+    name = "NvimTreeHiTest",
+    opts = {
+      desc = "nvim-tree: highlight test",
+    },
+    command = api.diagnostics.hi_test,
+  },
 }
 
 function M.get()