Get-VSExtension.ps1

function ConvertTo-Dictionary {

  param(
    [Parameter(Mandatory, Position = 0, ValueFromPipeline)]
    [PSObject[]] $InputObject = @())

  @($InputObject) | % {
    $result = @{}
    $obj = $_

    $props = $obj | Get-Member -MemberType Properties
    $props | % {
      $name = $_.Name
      $result[$name] = $obj.$name
    }

    return $result
  }
}

function Test-FileSystemPath {

  param(
    [Parameter(Mandatory, Position = 0)]
    [string] $Path)

  [System.Management.Automation.ProviderInfo] $provider = $null
  $ExecutionContext.SessionState.Path.GetResolvedProviderPathFromPSPath($Path, [ref] $provider) > $null

  $r = $provider.Name -eq 'FileSystem'
  return $r
}

function Get-ExtensionName {

  param(
    [Parameter(Mandatory, Position = 0)]
    [string] $Path)

  if ($ExecutionContext.SessionState.InvokeProvider.Item.IsContainer($Path)) {
    $Path = Join-Path $Path 'extension.vsixmanifest'
  }

  $manifest = [xml] (Get-Content $Path)

  if ($manifest.PackageManifest) {
    $name = $manifest.PackageManifest.Metadata.DisplayName
  }
  elseif ($manifest.Vsix) {
    $name = $manifest.Vsix.Identifier.Name
  }
  else {
    throw "Unknown Manifest Schema : $Path"
  }

  if ($name.'#text') {
    $name = $name.'#text'
  }

  return $name
}

function Get-VSExtension {

  param(
    [string] $VSVersion = '14.0')

  $props = Get-ItemProperty "HKCU:\Software\Microsoft\VisualStudio\$VSVersion\ExtensionManager\EnabledExtensions"
  $props = $props | ConvertTo-Dictionary
  $props.Keys | % {

    $key = $_
    $value = $props[$key]

    $path = $value

    if (!(Test-Path $path)) {
      return
    }

    if (!(Test-FileSystemPath $path)) {
      return
    }

    $name = Get-ExtensionName $path

    [PSCustomObject] @{
      Name = $name
      Path = $path
    }
  }

}