$MyInvocation.PSCommandPath unexpectedly returns $null rather than the empty string when there is no calling script.

[mklement0]

Prerequisites

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• Make sure you are able to repro it on the latest released version
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• Refer to Differences between Windows PowerShell 5.1 and PowerShell.

Steps to reproduce

$MyInvocation.PSScriptRoot and $MyInvocation.ScriptName, which is the older equivalent of $MyInvocation.PSCommandPath, sensibly report '', i.e. the empty string in case there is no calling script.

Unexpectedly, $MyInvocation.PSCommandPath reports $null instead in this situation.
Not just for consistency with the other properties, but for consistency with PowerShell's general behavior of not using $null in string contexts, this should be fixed.

However, given that there may be existing code that explicitly tests for $null, it should at least be documented.

& { '' -eq $MyInvocation.PSCommandPath; $null -eq $MyInvocation.PSCommandPath }

Expected behavior

True
False

Actual behavior

False
True

That is, $MyInvocation.PSCommandPath unexpectedly returned $null.

Error details

No response

Environment data

PowerShell 7.5.0-preview.2

Visuals

No response