Created a custom plugin, it loads but I get cache.lua invalid value (table) at index 2

[squareborg]

Hi I tried to create my own custom completion plugin for cmp,

it seems CMP loads it as I can see it in CmpStatus but on every keypress I get this error:

Any ideas? Thanks

Error detected while processing TextChangedI Autocommands for "*":
Error executing lua callback: .../.local/share/nvim/lazy/nvim-cmp/lua/cmp/utils/cache.lua:15: invalid value (table) at index 2 in table for 'concat'
stack traceback:
	[C]: in function 'key'
	.../.local/share/nvim/lazy/nvim-cmp/lua/cmp/utils/cache.lua:15: in function 'get'
	.../.local/share/nvim/lazy/nvim-cmp/lua/cmp/utils/cache.lua:36: in function 'get_offset'
	...s/stm/.local/share/nvim/lazy/nvim-cmp/lua/cmp/source.lua:270: in function 'complete'
	/Users/stm/.local/share/nvim/lazy/nvim-cmp/lua/cmp/core.lua:299: in function 'complete'
	/Users/stm/.local/share/nvim/lazy/nvim-cmp/lua/cmp/core.lua:169: in function 'callback'
	/Users/stm/.local/share/nvim/lazy/nvim-cmp/lua/cmp/core.lua:229: in function 'autoindent'
	/Users/stm/.local/share/nvim/lazy/nvim-cmp/lua/cmp/core.lua:161: in function 'on_change'
	/Users/stm/.local/share/nvim/lazy/nvim-cmp/lua/cmp/init.lua:338: in function 'callback'
	...local/share/nvim/lazy/nvim-cmp/lua/cmp/utils/autocmd.lua:49: in function 'emit'
	...local/share/nvim/lazy/nvim-cmp/lua/cmp/utils/autocmd.lua:23: in function <...local/share/nvim/lazy/nvim-cmp/lua/cmp/utils/autocmd.lua:22>
Error detected while processing TextChangedI Autocommands for "*":

my plugin below

local M = {}
local source = {}

function source:is_available()
  return true
end
function source:get_debug_name()
  return "i8n"
end
function source:get_keyword_pattern()
  return { "t(" }
end
function source:get_trigger_characters()
  return { "'" }
end

local trans_table = {
  { label = "SomeThingHere" },
  { label = "AnotherThingHere" },
}

function source:complete(_, callback)
  print("in complete")
  callback({ items = trans_table })
end

function source:resolve(completion, callback)
  callback(completion)
end

function source:execute(completion, callback)
  callback(completion)
end

M.setup = function()
  require("cmp").register_source("i8n", source)
end

return M