fix(shared): avoid indexing unindexable values in vim.tbl_get()

runtime/lua/vim/shared.lua

@@ -365,7 +365,10 @@ function vim.tbl_get(o, ...)
   if #keys == 0 then
     return
   end
-  for _, k in ipairs(keys) do
+  for i, k in ipairs(keys) do
+    if type(o[k]) ~= 'table' and next(keys, i) then
+      return nil
+    end
     o = o[k]
     if o == nil then
       return

test/functional/lua/vim_spec.lua

@@ -492,6 +492,8 @@ describe('lua stdlib', function()
 
   it('vim.tbl_get', function()
     eq(true, exec_lua("return vim.tbl_get({ test = { nested_test = true }}, 'test', 'nested_test')"))
+    eq(NIL, exec_lua("return vim.tbl_get({ unindexable = true }, 'unindexable', 'missing_key')"))
+    eq(NIL, exec_lua("return vim.tbl_get({ unindexable = 1 }, 'unindexable', 'missing_key')"))
     eq(NIL, exec_lua("return vim.tbl_get({}, 'missing_key')"))
     eq(NIL, exec_lua("return vim.tbl_get({})"))
   end)