Resolve path to short (8.3) version

Resolve-ShortPath.ps1

<#
.SYNOPSIS
    Resolves the 8.3 short path (DOS-style) of a given filesystem path.

.DESCRIPTION
    This script uses the Windows FileSystemObject COM interface to retrieve the short (8.3 format)
    path of a given file or folder. It supports both files and directories, recursively resolving
    all path components to their short names.

    The output is a custom PowerShell object that includes the full resolved path, along with an
    added `ShortPath` property, which shows the equivalent 8.3 format path.

    Only filesystem paths are supported.

.PARAMETER Path
    The full path to a file or folder whose 8.3 short path should be resolved.

.EXAMPLE
    .\Resolve-ShortPath.ps1 -Path 'C:\Users\MyName\Documents\Long Folder Name'

    Returns an object containing the original resolved path and its corresponding 8.3 short path.

.OUTPUTS
    Custom PSObject with standard path properties and an additional `ShortPath` property.
#>


#requires -version 7.4

# this is one of Stéphane BARIZIEN's public domain scripts
# the most recent version can be found at:
# https://gist.github.com/sba923/54a260dbd0fcd6672de13cf9e81b41db#file-resolve-shortpath-ps1

param([Parameter(Mandatory = $true)][string] $Path)

# derived from https://devblogs.microsoft.com/scripting/use-powershell-to-display-short-file-and-folder-names/

$item = Get-Item -Path $Path -ErrorAction SilentlyContinue

if ($null -eq $item)
{
    Write-Error ("Cannot find path '{0}' because it does not exist." -f $Path)
    $null
    Exit(1)
}

if ($item.PSProvider.Name -ne 'FileSystem')
{
    Write-Error ("Only filesystem paths are supported")
    $null
    Exit(1)
}

$fso = New-Object -ComObject Scripting.FileSystemObject
function GetShortPath([string] $Path)
{
    $item = Get-Item -LiteralPath $Path -Force
    if ($item.PSIsContainer)
    {
        if ($item.PSParentPath -eq '')
        {
            return $item.FullName
        }
        $shortname = $fso.getfolder($item.FullName).ShortName 
        $parentpath = Split-Path -Path $Path -Parent
        return (Join-Path -Path (GetShortPath -Path $parentpath) -ChildPath $shortname)
    }
    else
    {
        $shortname = $fso.getfile($item.FullName).ShortName 
        $parentpath = Split-Path -Path $Path -Parent
        return (Join-Path -Path (GetShortPath -Path $parentpath) -ChildPath $shortname)
    } 
}

# get a PathInfo object for the item, then clone it so we're able to set the DefaultDisplayPropertySet
$resolvedpath = (Resolve-Path -Path $Path) | Select-Object -Property *

# compute the full short path i.e. short name for each of the path components
$shortpath = GetShortPath -Path $Path

# add ShortPath property
Add-Member -InputObject $resolvedpath -MemberType NoteProperty -Name ShortPath -Value $shortpath

# set the default property to 'ShortPath'
# derived from https://learn-powershell.net/2013/08/03/quick-hits-set-the-default-property-display-in-powershell-on-custom-objects/
#Give this object a unique typename
$resolvedpath.PSObject.Typenames.Insert(0, 'ResolvedShortPath')
#Configure a default display set
$defaultDisplaySet = 'ShortPath'
#Create the default property display set
$defaultDisplayPropertySet = New-Object System.Management.Automation.PSPropertySet('DefaultDisplayPropertySet', [string[]]$defaultDisplaySet)
$PSStandardMembers = [System.Management.Automation.PSMemberInfo[]]@($defaultDisplayPropertySet)
$resolvedpath | Add-Member MemberSet PSStandardMembers $PSStandardMembers

# output the final object
$resolvedpath