Update-PipeScript.ps1
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function Update-PipeScript { <# .SYNOPSIS Updates PowerShell and PipeScript ScriptBlocks .DESCRIPTION Updates ScriptBlocks written in PowerShell or PipeScript. Also updates blocks of text. Update-PipeScript is used by PipeScript transpilers in order to make a number of changes to a script. It can also be used interactively to transform scripts or text in a number of ways. #> [Alias('Update-ScriptBlock', 'ups')] param( # A Script Block, written in PowerShell or PipeScript. [Parameter(ValueFromPipeline,ValueFromPipelineByPropertyName)] [Alias('Definition')] [ScriptBlock] $ScriptBlock, # A block of text. [Parameter(ValueFromPipelineByPropertyName)] [string] $Text, # Replaces sections within text. -TextReplacement is a dictionary of replacements. # Keys in the dictionary must be a string describing a character range, in the form start,end. [Alias('ScriptReplacements','TextReplacements','ScriptReplacement')] [ValidateScript({ if (-not $_.Count) { return $true } $badKeys = $_.Keys -notmatch '^\d+,\d+$' if ($badKeys) { throw "-TextReplacement contains bad keys: $badKeys" } return $true })] [Collections.IDictionary] $TextReplacement, # If set, will replace items based off of the abstract syntax tree. [Alias('AstReplacements')] [ValidateScript({ $badKeys = foreach ($k in $_.Keys) { if ($k -isnot [Management.Automation.Language.Ast]) { $k } } if ($badKeys) { throw "-AstReplacement contains bad keys: $badKeys" } return $true })] [Collections.IDictionary] $AstReplacement = [Ordered]@{}, # If provided, will remove one or more parameters from a ScriptBlock. [string[]] $RemoveParameter, # A collection of variables to rename. [Collections.IDictionary] $RenameVariable, # If set, will transpile the updated script block. [switch] $Transpile ) begin { # Code gets a lot more readable when it matches indentation. function IndentScriptBlock { param( [Parameter(ValueFromPipeline)] $ScriptBlock, [int] $Indent, [switch] $IndentFirstLine ) process { $scriptBlockLines =@($scriptBlock -split '[\r\n]+') if ($scriptBlockLines.Length -eq 1) { return $ScriptBlock } $InHereDoc = $false $IsFirstLine = $true $newScriptBlock = @(foreach ($scriptBlockLine in $scriptBlockLines) { if ($IsFirstLine) { if (-not $IndentFirstLine) { $scriptBlockLine } else { (' ' * $Indent) + $scriptBlockLine } $IsFirstLine = $false } else { if (-not $InHereDoc) { (' ' * $Indent) + $scriptBlockLine } else { $scriptBlockLine } } if ($scriptBlockLine -match '@["'']$') { $InHereDoc = $true } elseif ($scriptBlockLine -match '^["'']@') { $InHereDoc = $false } }) -join [Environment]::NewLine [scriptblock]::Create($newScriptBlock) } } } process { # If no text replacements were passed if (-not $TextReplacement) { $TextReplacement = [Ordered]@{} # initialize the collection } # The next series of things can only happen if we're dealing with a ```[ScriptBlock]``` if ($ScriptBlock) { $Text = "$scriptBlock" # If we're removing parameters if ($RemoveParameter) { $myOffset = 0 $index = 0 # Find them within the AST. $paramsToRemove = $ScriptBlock.Ast.FindAll({param($ast) if ($ast -isnot [Management.Automation.Language.ParameterAst]) { return } foreach ($toRemove in $RemoveParameter) { if ($ast.name.variablePath -like $toRemove) { return $true } } }, $true) foreach ($paramToRemove in $paramsToRemove) { $start = $Text.IndexOf($paramToRemove.Extent.Text, $myOffset) $end = $start + $paramToRemove.Extent.Text.Length if (([Collections.IList]$paramToRemove.Parent.Parameters).IndexOf($paramToRemove) -lt $paramToRemove.Parent.Parameters.Count - 1) { $end = $text.IndexOf(',', $end) + 1 } else { $start = $text.LastIndexOf(",", $start) } $TextReplacement["$start,$end"] = '' $myOffset = $end } } if ($RenameVariable) { $variablesToRename = @($ScriptBlock.Ast.FindAll({ param($ast) if ($ast -isnot [Management.Automation.Language.VariableExpressionast]) { return $false } if ($RenameVariable.Contains("$($ast.VariablePath)")) { return $true} return $false }, $true)) $myOffset = 0 foreach ($var in $variablesToRename) { $renameToValue = $RenameVariable["$($var.VariablePath)"] $replaceVariableText = if ($var.Splatted) { '@' + ($renameToValue -replace '^[\$\@]') } else { '$' + ($renameToValue -replace '^[\$\@]') } $replaceVariableText = [PSObject]::New($replaceVariableText) $replaceVariableText.PSObject.Properties.Add([PSNoteProperty]::New('Inline', $true)) $astReplacement[$var] = $replaceVariableText $myOffset = $end } } if ($astReplacement.Count) { $myOffset = 0 $index = 0 $sortedReplacements = @( $astReplacement.GetEnumerator() | Sort-Object { $_.Key.Extent.StartOffset } | Select-Object -ExpandProperty Key ) foreach ($item in $sortedReplacements) { $start = $Text.IndexOf($item.Extent.Text, $myOffset) $end = $start + $item.Extent.Text.Length $TextReplacement["$start,$end"] = $astReplacement[$item] $myOffset = $end } } } $enumReplacements = @($TextReplacement.GetEnumerator() | Sort-Object { @($_.Key -split ',')[0] -as [int] }) $index = 0 $lineStart = [Regex]::new('(?>\r\n|\n|\A)', 'SingleLine,RightToLeft') $newScript = @( for ($i = 0; $i -lt $enumReplacements.Count; $i++) { $start, $end = $enumReplacements[$i].Key -split ',' -as [int[]] if (-not $start -and -not $end ) { continue } if ($start -gt $index) { $Text.Substring($index, $start - $index) } elseif ($start -lt $index) { # If the start was less than the index, we'd be replacing within what has already been replaced, continue # so continue. } $lineStartMatch = $lineStart.Match($text, $start) $enumReplacements[$i].Value | & { process { $in = $_ if ($in -is [string] -and $in) { if ($ScriptBlock -and -not $in.Inline) { '@''' + [Environment]::NewLine + $in + [Environment]::NewLine + '''@' } else { $in } } elseif ($in -is [boolean]) { if ($ScriptBlock) { "`$$in" } else { "$in".ToLower() } } elseif ($in.GetType -and $in.GetType().IsPrimitive) { $in } elseif ($in -is [ScriptBlock]) { $indentLevel = $start - $lineStartMatch.Index - $lineStartMatch.Length $in = IndentScriptBlock -ScriptBlock $in -Indent $indentLevel # If the script block is has an empty parameter block at the end if ($in.Ast.Extent -match 'param\(\)[\s\r\n]{0,}$') { # embed everything before that block. $in.Ast.Extent -replace 'param\(\)[\s\r\n]{0,}$' } else { # otherwise, embed the block. $in } } } } $index = $end } if ($index -lt $Text.Length) { $Text.Substring($index) } ) -join '' if ($ScriptBlock) { if ($Transpile) { [ScriptBlock]::Create($newScript) | .>Pipescript } else { [ScriptBlock]::Create($newScript) } } else { $newScript } } } |