feat(#1917): add diagnostic highlighting and icon placement (#2396)

* feat(#1917): add renderer.highlight_diagnostics

* feat(#1917): add renderer.highlight_diagnostics

* feat(#1917): add enderer.icons.diagnostics_placement

* feat(#1917): add renderer.icons.show.diagnostics

* feat(#1917): document highlight overrides

doc/nvim-tree-lua.txt

@@ -345,6 +345,7 @@ applying configuration.
         add_trailing = false,
         group_empty = false,
         highlight_git = false,
+        highlight_diagnostics = false,
         full_name = false,
         highlight_opened_files = "none",
         highlight_modified = "none",
@@ -373,6 +374,7 @@ applying configuration.
             },
           },
           git_placement = "before",
+          diagnostics_placement = "signcolumn",
           modified_placement = "after",
           padding = " ",
           symlink_arrow = " ➛ ",
@@ -381,6 +383,7 @@ applying configuration.
             folder = true,
             folder_arrow = true,
             git = true,
+            diagnostics = true,
             modified = true,
           },
           glyphs = {
@@ -689,15 +692,7 @@ Open a file or directory in your preferred application.
       Windows: `{ "/c", "start", '""' }`
 
 *nvim-tree.diagnostics*
-Show LSP and COC diagnostics in the signcolumn
+Show LSP and COC diagnostics.
-Note that the modified sign will take precedence over the diagnostics signs.
-
-    `NOTE`: it will use the default diagnostic color groups to highlight the signs.
-    If you wish to customize, you can override these groups:
-    - `NvimTreeLspDiagnosticsError`
-    - `NvimTreeLspDiagnosticsWarning`
-    - `NvimTreeLspDiagnosticsInformation`
-    - `NvimTreeLspDiagnosticsHint`
 
     *nvim-tree.diagnostics.enable*
     Enable/disable the feature.
@@ -881,7 +876,7 @@ Window / buffer setup.
       Type: `boolean`, Default: `false`
 
     *nvim-tree.view.signcolumn*
-    Show diagnostic sign column. Value can be `"yes"`, `"auto"`, `"no"`.
+    Show |signcolumn|. Value can be `"yes"`, `"auto"`, `"no"`.
       Type: `string`, Default: `"yes"`
 
     *nvim-tree.view.float*
@@ -910,6 +905,8 @@ Window / buffer setup.
 *nvim-tree.renderer*
 UI rendering setup
 
+    Highlight override precedence: git < opened < modified < diagnostics
+
     *nvim-tree.renderer.add_trailing*
     Appends a trailing slash to folder names.
       Type: `boolean`, Default: `false`
@@ -923,11 +920,17 @@ UI rendering setup
       Type: `boolean`, Default: `false`
 
     *nvim-tree.renderer.highlight_git*
-    Enable file highlight for git attributes using `NvimTreeGit*` highlight groups.
+    Enable highlight for git attributes using `NvimTreeGit*` highlight groups.
     Requires |nvim-tree.git.enable|
     This can be used with or without the icons.
       Type: `boolean`, Default: `false`
 
+    *nvim-tree.renderer.highlight_diagnostics*
+    Enable highlight for diagnostics using `LspDiagnosticsError*Text` highlight groups.
+    Requires |nvim-tree.diagnostics.enable|
+    This can be used with or without the icons.
+      Type: `boolean`, Default: `false`
+
     *nvim-tree.renderer.highlight_opened_files*
     Highlight icons and/or names for |bufloaded()| files using the
     `NvimTreeOpenedFile` highlight group.
@@ -979,6 +982,8 @@ UI rendering setup
     *nvim-tree.renderer.icons*
     Configuration options for icons.
 
+        Sign column icon precedence: git < modified < diagnostics
+
         *nvim-tree.renderer.icons.web_devicons*
         Configure optional plugin `"nvim-tree/nvim-web-devicons"`
 
@@ -1010,9 +1015,14 @@ UI rendering setup
         Place where the git icons will be rendered.
         Can be `"after"` or `"before"` filename (after the file/folders icons)
         or `"signcolumn"` (requires |nvim-tree.view.signcolumn| enabled).
-        Note that the diagnostic signs and the modified sign will take precedence over the git signs.
           Type: `string`, Default: `before`
 
+        *nvim-tree.renderer.icons.diagnostics_placement*
+        Place where the diagnostics icon will be rendered.
+        Can be `"after"` or `"before"` filename (after the file/folders icons)
+        or `"signcolumn"` (requires |nvim-tree.view.signcolumn| enabled).
+          Type: `string`, Default: `signcolumn`
+
         *nvim-tree.renderer.icons.modified_placement*
         Place where the modified icon will be rendered.
         Can be `"after"` or `"before"` filename (after the file/folders icons)
@@ -1048,6 +1058,11 @@ UI rendering setup
             Requires |git.enable| `= true`
               Type: `boolean`, Default: `true`
 
+            *nvim-tree.renderer.icons.show.diagnostics*
+            Show a diagnostics status icon, see |renderer.icons.diagnostics_placement|
+            Requires |diagnostics.enable| `= true`
+              Type: `boolean`, Default: `true`
+
             *nvim-tree.renderer.icons.show.modified*
             Show a modified icon, see |renderer.icons.modified_placement|
             Requires |modified.enable| `= true`
@@ -2079,6 +2094,14 @@ NvimTreeFileNew         (NvimTreeGitNew)
 NvimTreeFileDeleted     (NvimTreeGitDeleted)
 NvimTreeFileIgnored     (NvimTreeGitIgnored)
 
+There are also links for text highlight for diagnostic status, linked by
+default to their icon equivalent.
+
+NvimTreeLspDiagnosticsErrorText     (NvimTreeLspDiagnosticsError)
+NvimTreeLspDiagnosticsWarningText   (NvimTreeLspDiagnosticsWarning)
+NvimTreeLspDiagnosticsInfoText      (NvimTreeLspDiagnosticsInformation)
+NvimTreeLspDiagnosticsHintText      (NvimTreeLspDiagnosticsHint)
+
 There are 2 highlight groups for the live filter feature
 
 NvimTreeLiveFilterPrefix

lua/nvim-tree.lua

@@ -409,6 +409,7 @@ local DEFAULT_OPTS = { -- BEGIN_DEFAULT_OPTS
     add_trailing = false,
     group_empty = false,
     highlight_git = false,
+    highlight_diagnostics = false,
     full_name = false,
     highlight_opened_files = "none",
     highlight_modified = "none",
@@ -437,6 +438,7 @@ local DEFAULT_OPTS = { -- BEGIN_DEFAULT_OPTS
         },
       },
       git_placement = "before",
+      diagnostics_placement = "signcolumn",
       modified_placement = "after",
       padding = " ",
       symlink_arrow = " ➛ ",
@@ -445,6 +447,7 @@ local DEFAULT_OPTS = { -- BEGIN_DEFAULT_OPTS
         folder = true,
         folder_arrow = true,
         git = true,
+        diagnostics = true,
         modified = true,
       },
       glyphs = {

lua/nvim-tree/colors.lua

@@ -81,6 +81,14 @@ local function get_links()
     FileStaged = "NvimTreeGitStaged",
     FileDeleted = "NvimTreeGitDeleted",
     FileIgnored = "NvimTreeGitIgnored",
+    LspDiagnosticsError = "DiagnosticError",
+    LspDiagnosticsWarning = "DiagnosticWarn",
+    LspDiagnosticsInformation = "DiagnosticInfo",
+    LspDiagnosticsHint = "DiagnosticHint",
+    LspDiagnosticsErrorText = "NvimTreeLspDiagnosticsError",
+    LspDiagnosticsWarningText = "NvimTreeLspDiagnosticsWarning",
+    LspDiagnosticsInformationText = "NvimTreeLspDiagnosticsInformation",
+    LspDiagnosticsHintText = "NvimTreeLspDiagnosticsHintFile",
     Popup = "Normal",
     GitIgnored = "Comment",
     StatusLine = "StatusLine",

lua/nvim-tree/diagnostics.lua

@@ -5,24 +5,7 @@ local log = require "nvim-tree.log"
 
 local M = {}
 
-local GROUP = "NvimTreeDiagnosticSigns"
-
 local severity_levels = { Error = 1, Warning = 2, Information = 3, Hint = 4 }
-local sign_names = {
-  { "NvimTreeSignError", "NvimTreeLspDiagnosticsError" },
-  { "NvimTreeSignWarning", "NvimTreeLspDiagnosticsWarning" },
-  { "NvimTreeSignInformation", "NvimTreeLspDiagnosticsInformation" },
-  { "NvimTreeSignHint", "NvimTreeLspDiagnosticsHint" },
-}
-
-local function add_sign(linenr, severity)
-  local buf = view.get_bufnr()
-  if not vim.api.nvim_buf_is_valid(buf) or not vim.api.nvim_buf_is_loaded(buf) then
-    return
-  end
-  local sign_name = sign_names[severity][1]
-  vim.fn.sign_place(0, GROUP, sign_name, buf, { lnum = linenr, priority = 2 })
-end
 
 local function from_nvim_lsp()
   local buffer_severity = {}
@@ -85,14 +68,6 @@ local function is_using_coc()
   return vim.g.coc_service_initialized == 1
 end
 
-function M.clear()
-  if not M.enable or not view.is_buf_valid(view.get_bufnr()) then
-    return
-  end
-
-  vim.fn.sign_unplace(GROUP)
-end
-
 function M.update()
   if not M.enable or not core.get_explorer() or not view.is_buf_valid(view.get_bufnr()) then
     return
@@ -108,8 +83,6 @@ function M.update()
       buffer_severity = from_nvim_lsp()
     end
 
-    M.clear()
-
     local nodes_by_line = utils.get_nodes_by_line(core.get_explorer().nodes, core.get_nodes_starting_line())
     for _, node in pairs(nodes_by_line) do
       node.diag_status = nil
@@ -129,26 +102,18 @@ function M.update()
           then
             log.line("diagnostics", " matched fold node '%s'", node.absolute_path)
             node.diag_status = severity
-            add_sign(line, severity)
           elseif nodepath == bufpath then
             log.line("diagnostics", " matched file node '%s'", node.absolute_path)
             node.diag_status = severity
-            add_sign(line, severity)
           end
         end
       end
     end
     log.profile_end(profile)
+    require("nvim-tree.renderer").draw()
   end)
 end
 
-local links = {
-  NvimTreeLspDiagnosticsError = "DiagnosticError",
-  NvimTreeLspDiagnosticsWarning = "DiagnosticWarn",
-  NvimTreeLspDiagnosticsInformation = "DiagnosticInfo",
-  NvimTreeLspDiagnosticsHint = "DiagnosticHint",
-}
-
 function M.setup(opts)
   M.enable = opts.diagnostics.enable
   M.debounce_delay = opts.diagnostics.debounce_delay
@@ -160,14 +125,6 @@ function M.setup(opts)
 
   M.show_on_dirs = opts.diagnostics.show_on_dirs
   M.show_on_open_dirs = opts.diagnostics.show_on_open_dirs
-  vim.fn.sign_define(sign_names[1][1], { text = opts.diagnostics.icons.error, texthl = sign_names[1][2] })
-  vim.fn.sign_define(sign_names[2][1], { text = opts.diagnostics.icons.warning, texthl = sign_names[2][2] })
-  vim.fn.sign_define(sign_names[3][1], { text = opts.diagnostics.icons.info, texthl = sign_names[3][2] })
-  vim.fn.sign_define(sign_names[4][1], { text = opts.diagnostics.icons.hint, texthl = sign_names[4][2] })
-
-  for lhs, rhs in pairs(links) do
-    vim.cmd("hi def link " .. lhs .. " " .. rhs)
-  end
 end
 
 return M

lua/nvim-tree/renderer/builder.lua

@@ -5,6 +5,7 @@ local git = require "nvim-tree.renderer.components.git"
 local pad = require "nvim-tree.renderer.components.padding"
 local icons = require "nvim-tree.renderer.components.icons"
 local modified = require "nvim-tree.renderer.components.modified"
+local diagnostics = require "nvim-tree.renderer.components.diagnostics"
 
 local Builder = {}
 Builder.__index = Builder
@@ -72,6 +73,14 @@ function Builder:configure_git_icons_placement(where)
   return self
 end
 
+function Builder:configure_diagnostics_icon_placement(where)
+  if where ~= "after" and where ~= "before" and where ~= "signcolumn" then
+    where = "before" -- default before
+  end
+  self.diagnostics_placement = where
+  return self
+end
+
 function Builder:configure_modified_placement(where)
   if where ~= "after" and where ~= "before" and where ~= "signcolumn" then
     where = "after" -- default after
@@ -206,20 +215,29 @@ end
 function Builder:_get_git_icons(node)
   local git_icons = git.get_icons(node)
   if git_icons and #git_icons > 0 and self.git_placement == "signcolumn" then
-    local sign = git_icons[1]
+    table.insert(self.signs, { sign = git_icons[1].hl, lnum = self.index + 1, priority = 1 })
-    table.insert(self.signs, { sign = sign.hl, lnum = self.index + 1, priority = 1 })
     git_icons = nil
   end
   return git_icons
 end
 
+---@param node table
+---@return HighlightedString[]|nil icon
+function Builder:_get_diagnostics_icon(node)
+  local diagnostics_icon = diagnostics.get_icon(node)
+  if diagnostics_icon and self.diagnostics_placement == "signcolumn" then
+    table.insert(self.signs, { sign = diagnostics_icon.hl, lnum = self.index + 1, priority = 2 })
+    diagnostics_icon = nil
+  end
+  return diagnostics_icon
+end
+
 ---@param node table
 ---@return HighlightedString|nil icon
 function Builder:_get_modified_icon(node)
   local modified_icon = modified.get_icon(node)
   if modified_icon and self.modified_placement == "signcolumn" then
-    local sign = modified_icon
+    table.insert(self.signs, { sign = modified_icon.hl, lnum = self.index + 1, priority = 3 })
-    table.insert(self.signs, { sign = sign.hl, lnum = self.index + 1, priority = 3 })
     modified_icon = nil
   end
   return modified_icon
@@ -263,6 +281,12 @@ function Builder:_get_highlight_override(node, unloaded_bufnr)
     end
   end
 
+  -- diagnostic status
+  local diagnostic_highlight = diagnostics.get_highlight(node)
+  if diagnostic_highlight then
+    name_hl = diagnostic_highlight
+  end
+
   return icon_hl, name_hl
 end
 
@@ -270,9 +294,10 @@ end
 ---@param icon HighlightedString
 ---@param name HighlightedString
 ---@param git_icons HighlightedString[]|nil
+---@param diagnostics_icon HighlightedString|nil
 ---@param modified_icon HighlightedString|nil
 ---@return HighlightedString[]
-function Builder:_format_line(padding, icon, name, git_icons, modified_icon)
+function Builder:_format_line(padding, icon, name, git_icons, diagnostics_icon, modified_icon)
   local added_len = 0
   local function add_to_end(t1, t2)
     for _, v in ipairs(t2) do
@@ -298,13 +323,21 @@ function Builder:_format_line(padding, icon, name, git_icons, modified_icon)
   if modified_icon and self.modified_placement == "before" then
     add_to_end(line, { modified_icon })
   end
+  if diagnostics_icon and self.diagnostics_placement == "before" then
+    add_to_end(line, { diagnostics_icon })
+  end
+
   add_to_end(line, { name })
+
   if git_icons and self.git_placement == "after" then
     add_to_end(line, git_icons)
   end
   if modified_icon and self.modified_placement == "after" then
     add_to_end(line, { modified_icon })
   end
+  if diagnostics_icon and self.diagnostics_placement == "after" then
+    add_to_end(line, { diagnostics_icon })
+  end
 
   return line
 end
@@ -314,6 +347,7 @@ function Builder:_build_line(node, idx, num_children, unloaded_bufnr)
   local padding = pad.get_padding(self.depth, idx, num_children, node, self.markers)
   local git_icons = self:_get_git_icons(node)
   local modified_icon = self:_get_modified_icon(node)
+  local diagnostics_icon = self:_get_diagnostics_icon(node)
 
   -- main components
   local is_folder = node.nodes ~= nil
@@ -336,7 +370,7 @@ function Builder:_build_line(node, idx, num_children, unloaded_bufnr)
     name.hl = name_hl
   end
 
-  local line = self:_format_line(padding, icon, name, git_icons, modified_icon)
+  local line = self:_format_line(padding, icon, name, git_icons, diagnostics_icon, modified_icon)
   self:_insert_line(self:_unwrap_highlighted_strings(line))
 
   self.index = self.index + 1

lua/nvim-tree/renderer/components/diagnostics.lua

@@ -0,0 +1,58 @@
+local M = {}
+
+local H = {}
+local I = {}
+
+---diagnostics text highlight group if there is a status
+---@param node table
+---@return string|nil highlight
+function M.get_highlight(node)
+  if M.config.diagnostics.enable and M.config.renderer.highlight_diagnostics then
+    return H[node.diag_status]
+  end
+end
+
+---diagnostics icon if there is a status
+---@param node table
+---@return HighlightedString|nil modified icon
+function M.get_icon(node)
+  if M.config.diagnostics.enable and M.config.renderer.icons.show.diagnostics then
+    return I[node.diag_status]
+  end
+end
+
+function M.setup(opts)
+  M.config = {
+    diagnostics = opts.diagnostics,
+    renderer = opts.renderer,
+  }
+
+  H[vim.diagnostic.severity.ERROR] = "NvimTreeLspDiagnosticsErrorText"
+  H[vim.diagnostic.severity.WARN] = "NvimTreeLspDiagnosticsWarningText"
+  H[vim.diagnostic.severity.INFO] = "NvimTreeLspDiagnosticsInfoText"
+  H[vim.diagnostic.severity.HINT] = "NvimTreeLspDiagnosticsHintText"
+
+  I[vim.diagnostic.severity.ERROR] = {
+    str = M.config.diagnostics.icons.error,
+    hl = "NvimTreeLspDiagnosticsError",
+  }
+
+  I[vim.diagnostic.severity.WARN] = {
+    str = M.config.diagnostics.icons.warning,
+    hl = "NvimTreeLspDiagnosticsWarning",
+  }
+  I[vim.diagnostic.severity.INFO] = {
+    str = M.config.diagnostics.icons.info,
+    hl = "NvimTreeLspDiagnosticsInfo",
+  }
+  I[vim.diagnostic.severity.HINT] = {
+    str = M.config.diagnostics.icons.hint,
+    hl = "NvimTreeLspDiagnosticsHint",
+  }
+
+  for _, i in ipairs(I) do
+    vim.fn.sign_define(i.hl, { text = i.str, texthl = i.hl })
+  end
+end
+
+return M

lua/nvim-tree/renderer/init.lua

@@ -1,5 +1,4 @@
 local core = require "nvim-tree.core"
-local diagnostics = require "nvim-tree.diagnostics"
 local log = require "nvim-tree.log"
 local view = require "nvim-tree.view"
 local events = require "nvim-tree.events"
@@ -9,6 +8,7 @@ local _padding = require "nvim-tree.renderer.components.padding"
 local icon_component = require "nvim-tree.renderer.components.icons"
 local full_name = require "nvim-tree.renderer.components.full-name"
 local git = require "nvim-tree.renderer.components.git"
+local diagnostics = require "nvim-tree.renderer.components.diagnostics"
 local Builder = require "nvim-tree.renderer.builder"
 local live_filter = require "nvim-tree.live-filter"
 local marks = require "nvim-tree.marks"
@@ -69,6 +69,7 @@ function M.draw(unloaded_bufnr)
     :configure_modified_highlighting(M.config.highlight_modified)
     :configure_icon_padding(M.config.icons.padding)
     :configure_git_icons_placement(M.config.icons.git_placement)
+    :configure_diagnostics_icon_placement(M.config.icons.diagnostics_placement)
     :configure_modified_placement(M.config.icons.modified_placement)
     :configure_symlink_destination(M.config.symlink_destination)
     :configure_filter(live_filter.filter, live_filter.prefix)
@@ -84,7 +85,6 @@ function M.draw(unloaded_bufnr)
     vim.api.nvim_win_set_cursor(view.get_winnr(), cursor)
   end
 
-  diagnostics.update()
   marks.draw()
 
   view.grow_from_content()
@@ -102,6 +102,7 @@ function M.setup(opts)
   full_name.setup(opts)
   git.setup(opts)
   modified.setup(opts)
+  diagnostics.setup(opts)
   icon_component.setup(opts)
 end