Mock [System.IO.Path]::IsPathRooted() using Pester?

Question

How do I Mock [System.IO.Path]::IsPathRooted() using Pester? I tried the following but no luck.

Describe "Configuration" {
    Mock [System.IO.Path]::IsPathRooted {
        return false
    }

    It "should mock rooted Path" {
        [System.IO.Path]::IsPathRooted("C:\a") | Should Be False
    }

Answer 1

Unfortunately the answer to your question is short and simple:

You can't.

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According to Pester's Github Issue #72, the best alternative is to wrap the method call in a separate function and Mock this function.

There are a few discussions about this and a lot of people would love to be able to mock .Net methods, but until now, I was unable to find any solution on this. Unfortunately, even overwriting methods (independent of Pester) isn't that easy.