Script Analyzer sample 1

ScriptAnalyzer.ps1

<#
.SYNOPSIS
    You should never use Write-Host to create any script output whatsoever.
.DESCRIPTION
    It is generally accepted that you should never use Write-Host to create any script output whatsoever, unless your script (or function, or whatever) uses the Show verb (as in, Show-Performance).
    That verb explicitly means “show on the screen, with no other possibilities.” Like Show-Command.
    To fix a violation of this rule, please replace Write-Host with Write-Output in most scenarios.
.EXAMPLE
    Test-WriteHost -CommandAst $CommandAst
.INPUTS
    [System.Management.Automation.Language.CommandAst]
.OUTPUTS
    [PSCustomObject[]]
.NOTES
    Reference: Output, The Community Book of PowerShell Practices.
#>
function Test-WriteHost
{
    [CmdletBinding()]
    [OutputType([PSCustomObject[]])]
    Param
    (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [System.Management.Automation.Language.CommandAst]
        $CommandAst
    )
 
    Process
    {
        try
        {
            $commandName = $CommandAst.GetCommandName()
            # Checks command name, if the command name matches Write-Host or
            # user-defined aliases, this rule is triggered.
 
            if ($null -ne $commandName)
            {
                $alias = (Get-Alias -Definition "Write-Host" -ErrorAction SilentlyContinue).Name
 
                if (($commandName -eq "Write-Host") -or
                    ($alias -eq $commandName))
                {
                    [PSCustomObject]@{Message  = "Avoid Using Write-Host";
                                      Extent   = $CommandAst.Extent;
                                      RuleName = $PSCmdlet.MyInvocation.InvocationName;
                                      Severity = "Warning"}                   
                }
            }
        }
        catch
        {
            $PSCmdlet.ThrowTerminatingError($PSItem)
        }
    }
}