Adding empty line in powershell script creates errors

Question

I have just encountered a very weird error: whenever I just add an empty line in a ps1 file which is otherwise working really fine, my script generates errors.

Here is the setup:

Because I had dependencies issues, I now have an Includes.ps1 file with that content:

$ScriptDirectory = Split-Path -Path $MyInvocation.MyCommand.Definition -Parent

. ("$ScriptDirectory\HelperFunctions.ps1")
. ("$ScriptDirectory\BuildParameters.ps1")
. ("$ScriptDirectory\Platform.ps1")
. ("$ScriptDirectory\Configuration.ps1")
. ("$ScriptDirectory\Action.ps1")
. ("$ScriptDirectory\Backup.ps1")

I have a Package.ps1 file which includes that file, and does the stuff of instanciating the needed classes and make them work together:

$ScriptDirectory = Split-Path -Path $MyInvocation.MyCommand.Definition -Parent
. ("$ScriptDirectory\Includes.ps1")

Clear-Host

$Parameters = New-Object -TypeName "BuildParameters"

$user_variables_path = "./UserVariables.ps1"

if ( Test-Path $user_variables_path )
{
    . $user_variables_path
}

$Parameters.ValidateParameters()

$PlatformClass = $PlatformFactory.MakePlatform( $Parameters.Platform )
$PlatformClass.ValidateParameters( $Parameters )

$ConfigurationClass = $ConfigurationFactory.MakeConfiguration( $Parameters.Configuration )
$ConfigurationClass.ValidateParameters( $Parameters )

$ActionClass = $ActionsFactory.MakeAction( $Parameters.Action, $PlatformClass, $ConfigurationClass, $Parameters )
$ActionClass.ValidateParameters()

$Backup = [ Backup ]::new( $Parameters, $PlatformClass )
$Backup.ValidateParameters();

$ActionClass.Execute()

if ( $Parameters.BackupVersion )
{
    $Backup.BackupVersion()
}

Here is the Platforms.ps1 file which gives me errors when I edit it:

class Platform
{
    [Boolean] $CanBePatched
    [Boolean] $CanCompressData

    Platform()
    {
        $this.CanBePatched = $false
        $this.CanCompressData = $true
    }

    [void] ValidateParameters( [BuildParameters] $Parameters )
    {
    }
}

class PlatformWin64 : Platform
{
    PlatformWin64()
    {
    }
}

class PlatformXboxOne : Platform
{
    PlatformXboxOne()
    {
    }
}

class PlatformSwitch : Platform
{
    PlatformSwitch()
    {
        $this.CanBePatched = $true
    }

    [void] ValidateParameters( [BuildParameters] $Parameters )
    {
        if ( [string]::IsNullOrEmpty( $Parameters.Region ) )
        {
            WriteErrorAndExit( "You need to specify a region for the PS4" )
        }
    }
}

class PlatformPS4 : Platform
{
    PlatformPS4()
    {
        $this.CanBePatched = $true
        $this.CanCompressData = $false
    }

    [void] ValidateParameters( [BuildParameters] $Parameters )
    {
        if ( [string]::IsNullOrEmpty( $Parameters.Region ) )
        {
            WriteErrorAndExit( "You need to specify a region for the PS4" )
        }
    }
}

class PlatformFactory
{
    [Platform] MakePlatform( [String] $name )
    {
        return (New-Object -TypeName "Platform$name")
    }
}

$PlatformFactory = [PlatformFactory]::new()

When I change the contents of that file, even by adding empty lines, running the script gives me those errors:

Cannot convert argument "Platform", with value: "PlatformWin64", for
"MakeAction" to type "Platform": "Cannot convert the "PlatformWin64" value
of type "PlatformWin64" to type "Platform"."
At F:\Projects\RWC\BuildScripts\Utils\Package.ps1:55 char:1
+ $ActionClass = $ActionsFactory.MakeAction( $Parameters.Action, $Platf ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodException
    + FullyQualifiedErrorId : MethodArgumentConversionInvalidCastArgument

You cannot call a method on a null-valued expression.
At F:\Projects\RWC\BuildScripts\Utils\Package.ps1:56 char:1
+ $ActionClass.ValidateParameters()
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

Cannot convert argument "Platform", with value: "PlatformWin64", for
".ctor" to type "Platform": "Cannot convert the "PlatformWin64" value of
type "PlatformWin64" to type "Platform"."
At F:\Projects\RWC\BuildScripts\Utils\Package.ps1:58 char:1
+ $Backup = [ Backup ]::new( $Parameters, $PlatformClass )
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodException
    + FullyQualifiedErrorId : MethodArgumentConversionInvalidCastArgument

You cannot call a method on a null-valued expression.
At F:\Projects\RWC\BuildScripts\Utils\Package.ps1:59 char:1
+ $Backup.ValidateParameters();
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

You cannot call a method on a null-valued expression.
At F:\Projects\RWC\BuildScripts\Utils\Package.ps1:61 char:1
+ $ActionClass.Execute()
+ ~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

You cannot call a method on a null-valued expression.
At F:\Projects\RWC\BuildScripts\Utils\Package.ps1:65 char:5
+     $Backup.BackupVersion()
+     ~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

`Cannot convert argument "Platform", with value: "PlatformWin64", for "MakeAction" to type "Platform"` You have a type mismatch where implicit conversion is failing. — Maximilian Burszley, Aug 29 '18 at 14:12
I give to the script the **Platform** argument with Win64. This then calls PlatformFactory::MakePlatform with PlatformWin64, which is a valid class type. And this does not make any clearer why by adding some empty lines, I have this error ^^ — Emidee, Aug 29 '18 at 14:33
`Platform` needs to exist **before** you can inherit from it. Having it in the same file is probably the cause of your problem due to how powershell parses classes. — Maximilian Burszley, Aug 29 '18 at 14:42
I just created a PlatformWin64.ps1 file with the class inside, add that new script to the includes.ps1, but I still get the same error — Emidee, Aug 29 '18 at 14:47

score 1 · Answer 1 · answered Aug 29 '18 at 15:04

1

Well it turns out I had to close the powershell command line and run it again to have my modifications not generate any errors.

That post helped me find the cause...

answered Aug 29 '18 at 15:04

Emidee

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Adding empty line in powershell script creates errors

1 Answers1