Unstall-PSResource does not uninstall dependencies

[SimonWahlin]

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest released version
• Search the existing issues.

Steps to reproduce

When uninstalling a module (ModuleA) which has a dependency on another module (ModuleB) and no other module depends on ModuleB, ModuleB is not uninstalled when uninstalling ModuleA.

Repro:

# I first make sure I don't have any Az* modules installed
Get-Module Az* -ListAvailable
# Installing Az.Storage will also install Az.Accounts
Install-PSResource Az.Storage -TrustRepository
# Confirm I now have Az.Storage and Az.Accounts installed
Get-Module Az* -ListAvailable
# Now uninstall Az.Storage
Uninstall-PSResource -Name Az.Storage
# Az.Accounts is still installed altho nothing is depending on it and I have not explicitly installed it
Get-Module Az* -ListAvailable

Expected behavior

If I install a module that comes with a set of dependencies, I would expect those dependencies to be uninstalled with the module or at least that I'm informed about them being left behind.

I realise there might be scenarios where removing dependencies might be unwanted, like if I explicitly have installed the dependency. Maybe that could be solved with an opt-in solution like a -IncludeDependency parameter.

Actual behavior

Only the module I uninstall is removed, not any of the dependencies.

Error details

No response

Environment data

Get-Module Microsoft.PowerShell.PSResourceGet

ModuleType Version    PreRelease Name                                ExportedCommands
---------- -------    ---------- ----                                ----------------
Binary     0.5.23     beta23     Microsoft.PowerShell.PSResourceGet  {Find-PSResource, Get-InstalledPSResource, Get-PS…

$PSVersionTable

Name                           Value
----                           -----
PSVersion                      7.3.4
PSEdition                      Core
GitCommitId                    7.3.4
OS                             Darwin 22.5.0 Darwin Kernel Version 22.5.0: Thu Jun  8 22:22:23 PDT 2023; root:xnu-8796…
Platform                       Unix
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Visuals

[wekempf]

Developer types would expect this behavior, but I suspect most users would be shocked if they used commands from a dependency on the regular that suddenly stopped working because they removed a different resource. Even those of us that would understand and expect this behavior could be caught by it. What I'd suggest:

• By default, do not remove any resource but the resource requested.
  • Inform the user of any resource dependencies left behind and what remaining resources may still depend on those resources.
• Provide a switch to remove dependencies as well
  • Only those with no other resources dependent on them would be removed (obviously)
  • Inform the user of dependencies removed and left behind (detailing what resources still depend on it)