fix: restore system parser runtime path when vimdoc parser is missing

init.lua

@@ -1,6 +1,22 @@
 vim.g.base46_cache = vim.fn.stdpath "data" .. "/base46/"
 vim.g.mapleader = " "
 
+local function ensure_system_parsers_on_rtp()
+  if #vim.api.nvim_get_runtime_file("parser/vimdoc.*", false) > 0 then
+    return
+  end
+
+  for _, dir in ipairs { "/usr/lib/nvim", "/usr/lib64/nvim" } do
+    if vim.uv.fs_stat(dir .. "/parser") then
+      vim.opt.rtp:append(dir)
+      return
+    end
+  end
+end
+
+-- Distro packages may ship parsers under /usr/lib*/nvim instead of runtime/.
+ensure_system_parsers_on_rtp()
+
 -- bootstrap lazy and all plugins
 local lazypath = vim.fn.stdpath "data" .. "/lazy/lazy.nvim"
 
@@ -25,6 +41,9 @@ require("lazy").setup({
   { import = "plugins" },
 }, lazy_config)
 
+-- lazy can rewrite rtp, so restore system parser path after setup too.
+ensure_system_parsers_on_rtp()
+
 -- load theme
 dofile(vim.g.base46_cache .. "defaults")
 dofile(vim.g.base46_cache .. "statusline")