have to default to global shiftwidth

lua/nvim-treesitter/indent.lua

@@ -107,8 +107,11 @@ end, function(bufnr, root, lang)
   return tostring(bufnr) .. root:id() .. '_' .. lang
 end)
 
+---@param bufnr integer
+---@param lang string
+---@return integer
 local get_language_shiftwidth = memoize(function(bufnr, lang)
-  local buffer_shiftwidth = vim.bo.shiftwidth
+  ---@type integer
   local global_shiftwidth = vim.go.shiftwidth
   -- See :h 'shiftwidth': If set to 0, should use tabstop (0 is not the default value,
   -- but users may rely on this behavior)
@@ -119,16 +122,19 @@ local get_language_shiftwidth = memoize(function(bufnr, lang)
     global_shiftwidth = vim.bo.tabstop
   end
 
+  ---@type integer|nil
   local lang_shiftwidth = nil
   -- Note: get_filetypes(lang) always includes `lang` in the returned array of filetypes even if
   -- `lang` is not a filetype
+  ---@type string[]
   local filetypes = vim.treesitter.language.get_filetypes(lang)
   for _, ft in ipairs(filetypes) do
     -- filetype.get_option will default to the global value for the option
     -- if (1) there is no local equivalent set, or (2) the filetype does not exist
+    ---@type integer
     local filetype_shiftwidth = vim.filetype.get_option(ft, 'shiftwidth')
     if filetype_shiftwidth == 0 then
-      filetype_shiftwidth = vim.filetype.get_option(ft, 'tabstop')
+      filetype_shiftwidth = vim.filetype.get_option(ft, 'tabstop')--[[@as integer]]
     end
     if filetype_shiftwidth ~= global_shiftwidth then
       lang_shiftwidth = filetype_shiftwidth
@@ -137,7 +143,7 @@ local get_language_shiftwidth = memoize(function(bufnr, lang)
 
   -- if lang_shiftwidth is nil, then it is either unset OR it is the same as
   -- global_shiftwidth
-  return lang_shiftwidth or global_shiftwidth or buffer_shiftwidth
+  return lang_shiftwidth or global_shiftwidth
 end, function(bufnr, lang)
   return tostring(bufnr) .. '_' .. lang
 end)