add syntax highlighting

lua/lib/format.lua

@@ -23,7 +23,9 @@ end
 local function dev_icons(pathname, isdir, open)
     if isdir == true then return default_icons(pathname, isdir, open) end
 
-    return api.nvim_call_function('WebDevIconsGetFileTypeSymbol', { pathname, isdir }) .. " "
+    local icon = api.nvim_call_function('WebDevIconsGetFileTypeSymbol', { pathname, isdir })
+    if icon == "" then return "" end
+    return icon  .. " "
 end
 
 local function get_icon_func_gen()
@@ -51,6 +53,67 @@ local function format_tree(tree)
     return dirs
 end
 
+local HIGHLIGHT_GROUPS = {
+    ['^.*%.md$'] = 'MarkdownFile';
+    ['^LICENSE$'] = 'LicenseFile';
+    ['^.*%.vim$'] = 'VimFile';
+    ['^.*%.c$'] = 'CFile';
+    ['^.*%.cpp$'] = 'CFile';
+    ['^.*%.cxx$'] = 'CFile';
+    ['^.*%.h$'] = 'CFile';
+    ['^.*%.hpp$'] = 'CFile';
+    ['^.*%.py$'] = 'PythonFile';
+    ['^.*%.lua$'] = 'LuaFile';
+    ['^.*%.rs$'] = 'RustFile';
+    ['^.*%.sh$'] = 'ShellFile';
+    ['^.*%.zsh$'] = 'ShellFile';
+    ['^.*%.csh$'] = 'ShellFile';
+    ['^.*%.rs$'] = 'RustFile';
+    ['^.*%.js$'] = 'JavascriptFile';
+    ['^.*%.json$'] = 'JsonFile';
+    ['^.*%.toml$'] = 'TomlFile';
+    ['^.*%.yml$'] = 'YamlFile';
+    ['^.*%.gitignore$'] = 'GitignoreFile';
+    ['^.*%.ts$'] = 'TypescriptFile';
+    ['^.*%.jsx$'] = 'ReactFile';
+    ['^.*%.tsx$'] = 'ReactFile';
+    ['^.*%.html?$'] = 'HtmlFile';
+    ['^.*%.png$'] = 'ImageFile';
+    ['^.*%.jpe?g$'] = 'ImageFile';
+}
+
+local function highlight_line(buffer)
+    local function highlight(group, line, from, to)
+        vim.api.nvim_buf_add_highlight(buffer, -1, group, line, from, to)
+    end
+    return function(line, node)
+        local text_start = node.depth * 2 + 4
+        if node.dir then
+            if node.name ~= '..' then
+                highlight('LuaTreeFolderIcon', line, 0, text_start)
+                highlight('LuaTreeFolderName', line, text_start, -1)
+            else
+                highlight('LuaTreeFolderName', line, 0, -1)
+            end
+        else
+            for k, v in pairs(HIGHLIGHT_GROUPS) do
+                if string.match(node.name, k) ~= nil then
+                    highlight('LuaTree' .. v, line, 0, text_start)
+                    break
+                end
+            end
+        end
+    end
+end
+
+local function highlight_buffer(buffer, tree)
+    local highlight = highlight_line(buffer)
+    for i, node in pairs(tree) do
+        highlight(i - 1, node)
+    end
+end
+
 return {
     format_tree = format_tree;
+    highlight_buffer = highlight_buffer;
 }

lua/tree.lua

@@ -1,5 +1,6 @@
 local lib_file = require 'lib/file'
 local format = require 'lib/format'.format_tree
+local highlight = require 'lib/format'.highlight_buffer
 
 local api = vim.api
 local function syslist(v) return api.nvim_call_function('systemlist', { v }) end
@@ -143,6 +144,7 @@ local function update_view(update_cursor)
 
     api.nvim_buf_set_option(buf, 'modifiable', true)
     api.nvim_buf_set_lines(buf, 0, -1, false, format(Tree))
+    highlight(buf, Tree)
     api.nvim_buf_set_option(buf, 'modifiable', false)
 
     if update_cursor == true then