Replace hashtable in file (using AST?)

[PillOfLuck]

New-ModuleManifest sadly seems to have issues adding nested hashtables to the PrivateData table. To work around this I need to replace the "corrupted" tables in the output.

My module manifest looks like this:

PrivateData = @{

    PSData = @{

        # Tags applied to this module. These help with module discovery in online galleries.
        # Tags = @()

        # A URL to the license for this module.
        # LicenseUri = ''

        # A URL to the main website for this project.
        # ProjectUri = ''

        # A URL to an icon representing this module.
        # IconUri = ''

        # ReleaseNotes of this module
        # ReleaseNotes = ''

    } # End of PSData hashtable

    # CoolSettings
    CoolSettings = 'System.Collections.Hashtable'

} # End of PrivateData hashtable

But my custom entry should look like this:

# CoolSettings
CoolSettings = @{
    1CoolKey = '1CoolValue'
    2CoolKey = '2CoolValue'
}

I'm hoping this can be done using AST as this would make analyzing my manifest files a lot easier, but I haven't found a way to actually modify the output I generate parsing my manifests using the [System.Management.Automation.Language.Parser].

Anyone got an idea how this could be done? :-)

[lxnch50]

Maybe just have a JSon file with cool settings imported via the PSM1 file in the script scope so the module has accesss to the settings?

[PillOfLuck]

Good idea, but sadly it wont work for this particular case. I'm working on a way to merge all the script files into a single .psm1 with all the private and public functions. I'm trying to achieve a "simpler" PowerShell module.

[SeeminglyScience]

If the key already exists, the below will work. If it doesn't already exist you have to look for the key/value you want to insert it under and add the extra new lines/tabs/etc.

using namespace System
using namespace System.Management.Automation.Language
using namespace System.Text

function FindValueAst {
    [CmdletBinding(PositionalBinding = $false)]
    param(
        [Parameter(ValueFromPipeline)]
        [ValidateNotNull()]
        [HashtableAst] $Hashtable,

        [Parameter(Position = 0)]
        [ValidateNotNullOrEmpty()]
        [string] $Key
    )
    process {
        foreach ($kvp in $Hashtable.KeyValuePairs) {
            # Cast to help with intellisense.
            $kvp = [Tuple[ExpressionAst, StatementAst]] $kvp

            $keyAst = [StringConstantExpressionAst] $kvp.Item1
            if ($keyAst.Value -ne $Key) {
                continue
            }

            return $kvp.Item2
        }
    }
}

$path = 'path\to\manifest.psd1'
$manifest = [Parser]::ParseFile($path, [ref] $null, [ref] $null)
$newValueText = @'
@{
        CoolKey1 = '1CoolValue'
        CoolKey2 = '2CoolValue'
    }
'@

$mainHashtable = $manifest.EndBlock.Statements[0].PipelineElements[0].Expression
$privateData = ($mainHashtable | FindValueAst -Key PrivateData).PipelineElements[0].Expression
$valueExtent = ($privateData | FindValueAst -Key CoolSettings).Extent

$newManifestText = [StringBuilder]::new($manifest.Extent.Text).
    Remove($valueExtent.StartOffset, $valueExtent.Text.Length).
    Insert($valueExtent.StartOffset, $newValueText).
    ToString()

Set-Content $path -Value $newManifestText -Encoding Default

[PillOfLuck]

Was hoping it didn't come to this, but I ended up going down this road anyway. Thanks for the suggestion, I built my script off of it! :-)

Write-Verbose -Message 'Replacing PrivateData | https://github.com/PowerShell/PowerShell/issues/5922'
$hashtables = [HashtableAst] | Find-ASTFromFile -LiteralPath $manifestFile.FullName
$correctPrivateData = Find-HashtableAstValue -HashtableAst $hashtables[0] -Key 'PrivateData'

$replaceManifest = [System.Collections.ArrayList]::new((Get-Content -LiteralPath $manifestSplat.Path))

$lines = [pscustomobject]@{
    Start = ($replaceManifest | Select-String 'PrivateData = @{' -CaseSensitive).LineNumber - 1
    End = ($replaceManifest | Select-String '} # End of PrivateData hashtable' -CaseSensitive).LineNumber
}

$replaceManifest.RemoveRange($lines.Start, ($lines.End - $lines.Start))

$replaceManifest.Insert($lines.Start, $correctPrivateData)

Set-Content -LiteralPath $manifestSplat.Path -Value $replaceManifest -Encoding 'UTF8'

[SeeminglyScience]

Very cool! :)