some refacto and start adding file creation/removal..

lua/lib/format.lua

@@ -0,0 +1,53 @@
+local api = vim.api
+
+local function get_padding(depth)
+    local str = ""
+
+    while 0 < depth do
+        str = str .. "  "
+        depth = depth - 1
+    end
+
+    return str
+end
+
+local function default_icons(_, isdir, open)
+    if isdir == true then
+        if open == true then return " " end
+        return " "
+    end
+
+    return ""
+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 }) .. " "
+end
+
+local function get_icon_func_gen()
+    if api.nvim_call_function('exists', { "WebDevIconsGetFileTypeSymbol" }) == 0 then
+        return dev_icons
+    else
+        return default_icons
+    end
+end
+
+local get_icon = get_icon_func_gen()
+
+local function format_tree(tree)
+    local dirs = {}
+
+    for i, node in pairs(tree) do
+        local padding = get_padding(node.depth)
+        local icon = get_icon(node.path .. node.name, node.dir, node.open)
+        dirs[i] = padding ..  icon .. node.name
+    end
+
+    return dirs
+end
+
+return {
+    format_tree = format_tree;
+}