PR Summary

Fix #11419
This addresses an issue where Windows PowerShell proxy modules have a priority over PS Core modules during WinCompat module import. (see #11419 )

PR Context

Implicit PS Remoting code (reused by WinCompat) is doing Export-PSSession -AllowClobber.
The fix is to omit -AllowClobber parameter if WinCompat:

1. is either importing a module that is one of the engine modules:

"Microsoft.PowerShell.Utility",
"Microsoft.PowerShell.Management",
"Microsoft.PowerShell.Diagnostics",
"Microsoft.PowerShell.Host",
"Microsoft.PowerShell.Security",
"Microsoft.WSMan.Management",
"Microsoft.PowerShell.Commands.Utility",
"Microsoft.PowerShell.Commands.Management",
"Microsoft.PowerShell.Commands.Diagnostics",
"Microsoft.PowerShell.ConsoleHost"

2. or is importing a module specified in powershell.config.json in WindowsPowerShellCompatibilityNoClobberModuleList list. (this list is empty by default)

If a module falls into one of these buckets, then PS-Core version of the module is imported first (for engine modules from $PSHOME\Modules), then proxies are generated for WinPS version of the module without -AllowClobber flag. This result s in proxy modules not having PS Core commands.

Fix #11419
Fix #12014

Also fixed a bug where WinCompat module DenyList was not working for module names containing dots . in some cases.

PR Checklist

• PR has a meaningful title
  • Use the present tense and imperative mood when describing your changes
• Summarized changes
• Make sure all .h, .cpp, .cs, .ps1 and .psm1 files have the correct copyright header
• This PR is ready to merge and is not Work in Progress.
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• Breaking changes
  • None
  • OR
  • Experimental feature(s) needed
    • Experimental feature name(s):
• User-facing changes
  • Not Applicable
  • OR
  • Documentation needed
    • Issue filed: Need to update WinCompat docs MicrosoftDocs/PowerShell-Docs#5724
• Testing - New and feature
  • N/A or can only be tested interactively
  • OR
  • Make sure you've added a new test if existing tests do not effectively test the code changed
• Tooling
  • I have considered the user experience from a tooling perspective and don't believe tooling will be impacted.
  • OR
  • I have considered the user experience from a tooling perspective and enumerated concerns in the summary. This may include:
    • Impact on PowerShell Editor Services which is used in the PowerShell extension for VSCode (which runs in a different PS Host).
    • Impact on Completions (both in the console and in editors) - one of PowerShell's most powerful features.
    • Impact on PSScriptAnalyzer (which provides linting & formatting in the editor extensions).
    • Impact on EditorSyntax (which provides syntax highlighting with in VSCode, GitHub, and many other editors).