diff --git a/runtime/lua/vim/_options.lua b/runtime/lua/vim/_options.lua
index 4a360c18e4..a61fa61256 100644
--- a/runtime/lua/vim/_options.lua
+++ b/runtime/lua/vim/_options.lua
@@ -174,6 +174,11 @@ local function new_buf_opt_accessor(bufnr)
 end
 
 local function new_win_opt_accessor(winid, bufnr)
+  -- TODO(lewis6991): allow passing both buf and win to nvim_get_option_value
+  if bufnr ~= nil and bufnr ~= 0 then
+    error('only bufnr=0 is supported')
+  end
+
   return setmetatable({}, {
     __index = function(_, k)
       if bufnr == nil and type(k) == 'number' then
@@ -184,11 +189,6 @@ local function new_win_opt_accessor(winid, bufnr)
         end
       end
 
-      if bufnr ~= nil and bufnr ~= 0 then
-        error('only bufnr=0 is supported')
-      end
-
-      -- TODO(lewis6991): allow passing both buf and win to nvim_get_option_value
       return api.nvim_get_option_value(k, {
         scope = bufnr and 'local' or nil,
         win = winid or 0,
@@ -196,7 +196,6 @@ local function new_win_opt_accessor(winid, bufnr)
     end,
 
     __newindex = function(_, k, v)
-      -- TODO(lewis6991): allow passing both buf and win to nvim_set_option_value
       return api.nvim_set_option_value(k, v, {
         scope = bufnr and 'local' or nil,
         win = winid or 0,
diff --git a/test/functional/lua/vim_spec.lua b/test/functional/lua/vim_spec.lua
index d50b646085..0814f42545 100644
--- a/test/functional/lua/vim_spec.lua
+++ b/test/functional/lua/vim_spec.lua
@@ -2023,6 +2023,16 @@ describe('lua stdlib', function()
     vim.cmd "enew"
     ]]
     eq(100, fn.luaeval 'vim.wo.scrolloff')
+
+    matches(
+      'only bufnr=0 is supported',
+      pcall_err(exec_lua, 'vim.wo[0][10].signcolumn = "no"')
+    )
+
+    matches(
+      'only bufnr=0 is supported',
+      pcall_err(exec_lua, 'local a = vim.wo[0][10].signcolumn')
+    )
   end)
 
   describe('vim.opt', function()