[Feature Request] Add configuration option to control PowerShell apartment state (STA / MTA)

[jxsword]

Description

Background

The Pester VSCode adapter currently runs PowerShell in a default apartment state (MTA) when executing tests. However, certain PowerShell modules or legacy code rely on STA (Single-Threaded Apartment) mode, which is required for proper functionality (e.g., COM interop, WPF UI controls, some third-party modules).

Through manual patching of the extension source code, I was able to force STA mode and successfully run my tests. But this requires rebuilding and installing a custom version, which is not sustainable for regular users.

Problem

There is currently no built-in way to choose the apartment state of the PowerShell runspace used by the extension. This causes test failures for users who need STA mode.

Suggested Solution

Add a user-configurable setting (e.g., pester.powerShellApartmentState) that allows switching between "STA" and "MTA" (default: "MTA" for backward compatibility). The extension should then create the PowerShell runspace with the selected apartment state.

Example configuration in settings.json:

"pester.powerShellApartmentState": "STA"

Implementation notes (for maintainers)

• The relevant code resides in Scripts/powershellRunner.ps1 (or wherever the PowerShell runspace is created).
• Currently, runspace creation uses [powershell]::Create() (or similar) without specifying apartment state.
• To support STA, the runspace should be created via [runspacefactory]::CreateRunspace() and set $runspace.ApartmentState = [System.Threading.ApartmentState]::STA.
• The configuration value could be passed from TypeScript (extension.ts) down to the PowerShell script as a parameter.

only modified code:

# Scripts\powershellRunner.ps1
# lines: 45-46
[PowerShell]$psinstance = if (!$NoSessionReuse -and (Test-Path Variable:__NODEPSINSTANCE)) {
	$GLOBAL:__NODEPSINSTANCE
}
else {
    # original code
	# [powershell]::Create()

    # modified code

	# {feiyu modify start}
	$runspace = [runspacefactory]::CreateRunspace()
	$runspace.ApartmentState = [System.Threading.ApartmentState]::STA # STA
	$runspace.Open()
	$psinstance = [powershell]::Create()
	$psinstance.Runspace = $runspace
	$psinstance
	# {feiyu modify end}
}

Why this is needed

• Users of STA-dependent modules currently have to fork and rebuild the extension.
• Adding this setting makes the extension more flexible and avoids obscure initialization errors.

Thank you for considering this feature!