ParameterValidation.Tests.ps1

function get-stuff {
    param (
        [ValidateSet('A','b','c','d')]
        [string]$user,

        [ValidateNotNullOrEmpty()]
        [string]$data
    )
}

describe "check for validation" {

    it "Should have validate set on User" {
        (Get-Command Get-Stuff).Parameters['user'].Attributes.ValidValues | Should -Be 'A','b','c','d'
    }
    
    it "Should have validatenotnullorempty on data" {
        (get-command get-stuff).parameters['data'].Attributes.TypeId.Name | Should -Contain 'ValidateNotNullOrEmptyAttribute'
    }
}