Rule Proposal: Warn on dot-sourced function

I've inherited a project where everything is in, for lack of a better description, undeclared global scope, spread across several files. Functions don't have always have parameters, and are called with a dot before the function name. Variables are treated as global, though not declared. For example:

c:\Utils.ps1

function Write-MyLog {
$itemToLog | out-file c:\mylog.txt -append
}

c:\Interface.ps1

. c:\Utils.ps1

$itemToLog = "Something happened"
. Write-MyLog

Miraculously, this all works. Of course, I dare not change anything.

I would love it if ". Write-MyLog" came up as a warning, and even more so if there were some indication that "$itemToLog" in C:\Interface.ps1 was being used by the function called from c:\Utils.ps1.

Beginnen Sie damit, das Verhalten in den Beispielskripten c:\Utils.ps1 und c:\Interface.ps1 zu reproduzieren, wobei Sie sich auf den dot-sourced Funktionsaufruf und die dateiübergreifende Variable $itemToLog konzentrieren. Erledigt bedeutet, dass der Analyzer vor dem angeforderten Konstrukt warnt und die angeforderte Angabe zur Variablennutzung liefert, wobei der Gültigkeitsbereich und die erwarteten Diagnosen abgestimmt sind.