fixed 16-color detection

nvim/lua/darcula/config/init.lua

@@ -22,6 +22,8 @@ local utils = require("darcula.utils")
 NV_DARCULA_COLOR_COLUMN = utils.parse_env("NV_DARCULA_COLOR_COLUMN", "80")
 NV_DARCULA_COLOR_SCHEME =
   utils.parse_env("NV_DARCULA_COLOR_SCHEME", "darcula_lush")
+NV_DARCULA_TERMGUI_COLORS =
+  utils.parse_env("NV_DARCULA_TERMGUI_COLORS", utils.detect_termguicolors())
 NV_DARCULA_ENABLE_COC = utils.parse_env("NV_DARCULA_ENABLE_COC", true)
 NV_DARCULA_ENABLE_CODE_LENS =
   utils.parse_env("NV_DARCULA_ENABLE_CODE_LENS", false)

nvim/lua/darcula/options.lua

@@ -101,7 +101,7 @@ vim.opt.splitbelow = true
 vim.opt.splitright = true
 vim.opt.syntax = "enable"
 vim.opt.tabstop = 2
-vim.opt.termguicolors = true
+vim.opt.termguicolors = NV_DARCULA_TERMGUI_COLORS
 vim.opt.undodir = vim.fs.joinpath(vim.fn.stdpath("data"), ".undo")
 vim.opt.undofile = true
 vim.opt.updatetime = 250

nvim/lua/darcula/plugins.lua

@@ -19,6 +19,9 @@
 --
 require("darcula.config")
 
+-- The colorscheme is loaded from this module, before darcula.options.
+vim.opt.termguicolors = NV_DARCULA_TERMGUI_COLORS
+
 vim.api.nvim_create_autocmd(
   "PackChanged",
   {

nvim/lua/darcula/setup/500_telescope.lua

@@ -69,7 +69,6 @@ require("telescope").setup {
     borderchars = {" ", " ", " ", " ", " ", " ", " ", " "},
     color_devicons = true,
     use_less = true,
-    set_env = {["COLORTERM"] = "truecolor"}, -- default = nil,
     file_previewer = require "telescope.previewers".vim_buffer_cat.new,
     grep_previewer = require "telescope.previewers".vim_buffer_vimgrep.new,
     qflist_previewer = require "telescope.previewers".vim_buffer_qflist.new,

nvim/lua/darcula/utils/init.lua

@@ -156,6 +156,35 @@ local function iff(b, l, r)
   return r
 end
 
+local detect_termguicolors = function()
+  local term = (vim.env.TERM or ""):lower()
+  if term == "ansi" or
+    term == "cons25" or
+    term == "dumb" or
+    term == "linux" or
+    term:match("^vt%d+$") or
+    term:find("16color", 1, true) then
+    return false
+  end
+
+  local colorterm = (vim.env.COLORTERM or ""):lower()
+  if colorterm == "24bit" or colorterm == "truecolor" then
+    return true
+  end
+
+  if vim.fn.executable("tput") == 1 then
+    local output = vim.fn.system({"tput", "colors"})
+    if vim.v.shell_error == 0 then
+      local color_count = tonumber(output:match("%d+"))
+      if color_count and color_count <= 16 then
+        return false
+      end
+    end
+  end
+
+  return true
+end
+
 local parse_env = function(var, def)
   if vim.env[var] ~= nil then
     if type(def) == "boolean" then
@@ -222,6 +251,7 @@ return {
   copy_file = copy_file,
   create_vert_display = create_vert_display,
   cword = cword,
+  detect_termguicolors = detect_termguicolors,
   file_exists = file_exists,
   get_current_filename = get_current_filename,
   get_files_sorted_without_extension = get_files_sorted_without_extension,