Clear deleted git branches

Clear-DeletedBranches.ps1

function Clear-DeletedBranches {
    [CmdletBinding(SupportsShouldProcess = $true, ConfirmImpact = 'High')]
    [Alias("cdb")]
    param(
        [Parameter(Mandatory = $false)]
        [string]
        $GitDir = $PWD
    )

    $defaultBranch = ((git symbolic-ref --short refs/remotes/origin/HEAD) -split "/")[1]
    Write-Host "Switching to branch [$defaultBranch]..." -ForegroundColor Yellow
    git checkout $defaultBranch

    $branchesBefore = git branch -a

    $branchesToPrune = git remote prune origin --dry-run
    if ($branchesToPrune) {
        Write-Host "Branches to Be Pruned..." -ForegroundColor Green
        Write-Host $branchesToPrune -ForegroundColor Red

        if ($PSCmdlet.ShouldProcess("Remove Local Branches?")) {
            git remote prune origin
            $branchesAfter = git branch -a
            $removed = Compare-Object -ReferenceObject $branchesBefore -DifferenceObject $branchesAfter
            foreach ($b in $removed.InputObject) {
                $localName = $b.Split('/')[-1]
                git branch -D $localName
            }
        }
    } else {
        Write-Host "Nothing To prune" -ForegroundColor Green
    }

    Write-Host "`nPulling changes from default branch..." -ForegroundColor Green
    git pull

    Write-Host "`nCurrent branches..." -ForegroundColor Green
    git branch -a
}