Use lua API function nvim_set_hl

Requires nvim 0.7+

Note (from docs):

The fg and bg keys also accept the string values `"fg"` or `"bg"`
which act as aliases to the corresponding foreground and background
values of the Normal group. If the Normal group has not been defined,
using these values results in an error.

Author: Jakub Łuczyński

README.md

@@ -12,7 +12,7 @@ Monokai Theme for Neovim with tree-sitter support
 
 ## Prerequisites
 
-Neovim >= 0.5.
+Neovim >= 0.7.
 
 ## Installation
 | Plugin Manager                                       | Command                                                                              |

lua/monokai.lua

@@ -118,23 +118,12 @@ M.ristretto = {
   diff_text = '#23324d',
 }
 
-local function remove_italics(config, colors)
-  if not config.italics and colors.style == 'italic' then
-    colors.style = nil
-  end
-  return colors
-end
-
 local function highlighter(config)
-  return function(group, color)
-    color = remove_italics(config, color)
-    local style = color.style and 'gui=' .. color.style or 'gui=NONE'
-    local fg = color.fg and 'guifg = ' .. color.fg or 'guifg = NONE'
-    local bg = color.bg and 'guibg = ' .. color.bg or 'guibg = NONE'
-    local sp = color.sp and 'guisp = ' .. color.sp or ''
-  vim.cmd(
-    'highlight ' .. group .. ' ' .. style .. ' ' .. fg .. ' ' .. bg .. ' ' .. sp
-  )
+  return function(group, val)
+    if not config.italics then
+        val.italic = false
+    end
+    vim.api.nvim_set_hl(0, group, val)
   end
 end
 
@@ -167,7 +156,7 @@ M.load_syntax = function(palette)
       bg = palette.base3,
     },
     Cursor = {
-      style = 'reverse',
+      reverse=true,
     },
     ColorColumn = {
       bg = palette.base3,
@@ -204,19 +193,19 @@ M.load_syntax = function(palette)
     },
     ModeMsg = {
       fg = palette.white,
-      style = 'bold',
+      bold = true,
     },
     MoreMsg = {
       fg = palette.white,
-      style = 'bold',
+      bold = true,
     },
     ErrorMsg = {
       fg = palette.red,
-      style = 'bold',
+      bold = true,
     },
     WarningMsg = {
       fg = palette.yellow,
-      style = 'bold',
+      bold = true,
     },
     VertSplit = {
       fg = palette.brown,
@@ -244,26 +233,26 @@ M.load_syntax = function(palette)
     },
     SpellBad = {
       fg = palette.red,
-      style = 'undercurl',
+      undercurl = true,
     },
     SpellCap = {
       fg = palette.purple,
-      style = 'undercurl',
+      undercurl = true,
     },
     SpellRare = {
       fg = palette.aqua,
-      style = 'undercurl',
+      undercurl = true,
     },
     SpellLocal = {
       fg = palette.pink,
-      style = 'undercurl',
+      undercurl = true,
     },
     SpecialKey = {
       fg = palette.pink,
     },
     Title = {
       fg = palette.yellow,
-      style = 'bold',
+      bold = true,
     },
     Directory = {
       fg = palette.aqua,
@@ -329,7 +318,7 @@ M.load_syntax = function(palette)
     },
     Function = {
       fg = palette.green,
-      style = 'italic',
+      italic = true,
     },
     Statement = {
       fg = palette.pink,
@@ -342,7 +331,7 @@ M.load_syntax = function(palette)
     },
     Keyword = {
       fg = palette.pink,
-      style = 'italic',
+      italic = true,
     },
     PreProc = {
       fg = palette.green,
@@ -370,7 +359,7 @@ M.load_syntax = function(palette)
     },
     SpecialComment = {
       fg = palette.grey,
-      style = 'italic',
+      italic = true,
     },
     Tag = {
       fg = palette.orange,
@@ -380,10 +369,10 @@ M.load_syntax = function(palette)
     },
     Comment = {
       fg = palette.base6,
-      style = 'italic',
+      italic = true,
     },
     Underlined = {
-      style = 'underline',
+      underline = true,
     },
     Ignore = {},
     Error = {
@@ -400,16 +389,16 @@ M.load_syntax = function(palette)
       fg = palette.grey,
     },
     vCursor = {
-      style = 'reverse',
+      reverse = true,
     },
     iCursor = {
-      style = 'reverse',
+      reverse = true,
     },
     lCursor = {
-      style = 'reverse',
+      reverse = true,
     },
     CursorIM = {
-      style = 'reverse',
+      reverse = true,
     },
     CursorColumn = {
       bg = palette.base3,
@@ -423,7 +412,7 @@ M.load_syntax = function(palette)
     },
     QuickFixLine = {
       fg = palette.purple,
-      style = 'bold',
+      bold = true,
     },
     Debug = {
       fg = palette.orange,
@@ -463,7 +452,7 @@ M.load_plugin_syntax = function(palette)
     },
     TSComment = {
       fg = palette.base6,
-      style = 'italic',
+      italic = true,
     },
     TSConstant = {
       fg = palette.aqua,
@@ -485,22 +474,22 @@ M.load_plugin_syntax = function(palette)
     },
     TSFunction = {
       fg = palette.green,
-      style = 'italic',
+      italic = true,
     },
     TSFuncBuiltin = {
       fg = palette.aqua,
     },
     TSFuncMacro = {
       fg = palette.green,
-      style = 'italic',
+      italic = true,
     },
     TSKeyword = {
       fg = palette.pink,
-      style = 'italic',
+      italic = true,
     },
     TSKeywordFunction = {
       fg = palette.pink,
-      style = 'italic',
+      italic = true,
     },
     TSKeywordOperator = {
       fg = palette.pink,
@@ -599,19 +588,19 @@ M.load_plugin_syntax = function(palette)
       fg = palette.aqua,
     },
     DiagnosticUnderlineError = {
-      style = 'undercurl',
+      undercurl=true,
       sp = palette.red,
     },
     DiagnosticUnderlineWarn = {
-      style = 'undercurl',
+      undercurl=true,
       sp = palette.yellow,
     },
     DiagnosticUnderlineInfo = {
-      style = 'undercurl',
+      undercurl=true,
       sp = palette.white,
     },
     DiagnosticUnderlineHint = {
-      style = 'undercurl',
+      undercurl=true,
       sp = palette.aqua,
     },
     CursorWord0 = {
@@ -630,7 +619,6 @@ M.load_plugin_syntax = function(palette)
     },
     NvimTreeSpecialFile = {
       fg = palette.white,
-      style = 'NONE',
     },
 
     -- Telescope
@@ -643,7 +631,7 @@ M.load_plugin_syntax = function(palette)
     },
     TelescopeSelection = {
       fg = palette.white,
-      style = 'bold',
+      bold=true,
     },
     TelescopeSelectionCaret = {
       fg = palette.green,
@@ -716,6 +704,9 @@ M.setup = function(config)
   local syntax = M.load_syntax(used_palette)
   syntax = vim.tbl_deep_extend('keep', config.custom_hlgroups, syntax)
   local highlight = highlighter(config)
+  -- https://github.com/neovim/neovim/issues/20008#issue-1355604714
+  -- normal must be defined first so that bg/fg can work
+  highlight('Normal', syntax['Normal'])
   for group, colors in pairs(syntax) do
     highlight(group, colors)
   end