XDT Transform: InsertBefore - Locator Condition is ignored

Question

I have a web.config file in which I need to either insert the element or manipulate children of that node if it already exists.
If

Answer 1

So after facing the same issue, I came up with a solution. It's not pretty nor elegant, but it works. (At least on my machine)

I just split the logic into 3 different statements. First, I add an empty configSections at the correct position (first). Then I insert the new config to the last configSections, which would be the new one if it is the only one, or a previously existing one otherwise. Lastly I remove any empty configSections elemnt which might exist. I'm using RemoveAll for no good reason, you should probably use Remove.

The overall code looks like so:

The question which still remains unanswered is why Locator conditions are not taken into account for InsertBefore. Or why I can't handle an empty match set for InsertBefore, because that would allowed me to do fun things such as

//configuration/*[position()=1 and not(local-name()='configSections')]

Which to be honest is a much clearer way of doing what I want to achieve.