config formatter not working?

[Dols592]

I'm trying to add a formatter to the configuration file. I run into a strange problem. I cannot use standard lua functions. for pairs, ipairs, table functions are not recognized.

I'm using the current latest version of the windows precompiled binairy of luacheck. Rest of config is empty.

This works:

  formatter = function(report, filenames, combined_opts)
    return "Test 1\r\nTest 2\r\n"
  end

This fails with error

Critical error: Couldn't run custom formatter 'function: 00000177b50307f0': [string "chunk"]:3: attempt to call a nil value (global 'pairs')

  formatter = function(report, filenames, combined_opts)
    local days = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"}
    for j, i in pairs(days) do
    end
    return ""
  end

[Dols592]

I fixed it by using the not a function but a custom formatter name.
Added next in the config file.
formatter = "customFormatter"

Next in the customFormatter.lua

return function(report, filenames, combined_opts)
    local days = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"}
    for j, i in pairs(days) do
    end
    return ""
end

Of course the content of the function is useless as a formatter. But is executed without errors.