PowerShell Split-Path does not work properly with IIS: drive qualifier - iis

Question

I am using PowerShell v3.0 and the IIS Administration Cmdlets to add and remove websites from my IIS 7 instance. I use Import-Module WebAdministration to make sure the IIS: drive is available, and I am able to use Remove-Item to delete files via the IIS: drive. For some reason though when I use the following code Split-Path always returns an empty string, even though the Remove-Item works fine.
$iisPath = Join-Path "IIS:\Sites" $fullPath
Remove-Item -Path $iisPath
$parent = Split-Path -Path $iisPath -Parent
Even if I comment out the Remove-Item line, Split-Path still returns an empty string. The $iisPath value would look something like this:
IIS:\Sites\Application Services\2.5.12\OurProductServicesDirectory
So I would expect $parent to contain:
IIS:\Sites\Application Services\2.5.12
But $parent is always empty. I have also tried creating the $iisPath using $iisPath = "IIS:\Sites\$fullPath", rather than Join-Path, but still get the same result.
Any ideas why Split-Path doesn't seem to work when using the IIS: drive, or how to fix it?
===UPDATE===
So I created a tiny sample script to see if I could reproduce the problem. Here it is:
$Block = {
Import-Module WebAdministration
$path = "IIS:\Sites\Application Services\2.5.12\OurProductServicesDirectory\"
Test-Path -Path $path
$parent = Split-Path -Path $path -Parent
Write-Host Parent is $parent
}
$Session = New-PSSession -ComputerName "Our.WebServer.local"
Invoke-Command -Session $Session -ScriptBlock $Block
Using this script $parent does get a value, but the text written to the console is:
True
Parent is IIS:Sites\Application Services
when I expect it to be:
True
Parent is IIS:\Sites\Application Services\2.5.12
So in my simple sample script I do get a value back, but it's the wrong value; it returns the grandparent directory instead of the parent directory, and it removes the backslash from after IIS:.
I'm not sure why I get different results in this sample script then in my main script, but both results appear to be wrong. Any suggestions are appreciated.

Answer 1

So because the IIS: qualifier is made valid by importing the WebAdministration module, I'm going to assume that Split-Path was simply never designed to work with the IIS: qualifier, and that is why it doesn't handle it properly.
The work around I found was simply to just exclude IIS:\Sites\ from my path when using Split-Path. So my original example would change to:
Remove-Item -Path "IIS:\Sites\$fullPath"
$parent = Split-Path -Path $fullPath -Parent
So basically I just leave IIS:\Sites\ off of all my paths, and then explicitly add it when needed, such as when calling Remove-Item, Test-Path, Get-ChildItems, etc. It's not the greatest solution, but it works.