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. .EXAMPLE Update-PipeScript -ScriptBlock { param($x,$y) } -RemoveParameter x .EXAMPLE Update-PipeScript -RenameVariable @{x='y'} -ScriptBlock {$x} .EXAMPLE Update-PipeScript -ScriptBlock { #region MyRegion 1 #endregion MyRegion 2 } -RegionReplacement @{MyRegion=''} #> [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', 'ReplaceText')] [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', 'ReplaceAST')] [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 replace regular expression matches. [Alias('ReplaceRegex', 'RegexReplacements')] [Collections.IDictionary] $RegexReplacement = [Ordered]@{}, # If provided, will replace regions. [Alias('ReplaceRegion')] [Collections.IDictionary] $RegionReplacement, # If provided, will remove one or more parameters from a ScriptBlock. [string[]] $RemoveParameter, # If provided, will insert text before any regular epxression match. [Collections.IDictionary] $InsertBefore, # If provided, will insert text after any regular expression match. [Collections.IDictionary] $InsertAfter, # A collection of variables to rename. [Collections.IDictionary] [Alias('RenameParameter')] $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) } } filter ReplaceWith { param($lineStartMatch) $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 } } } # Declare a Regex to find the start of the line. $lineStart = [Regex]::new('(?>\r\n|\n|\A)', 'SingleLine,RightToLeft') } 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" #region Remove Parameter # 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 } } }, $true) # Walk over each parameter to turn it into a text replacement foreach ($paramToRemove in $paramsToRemove) { # Determine where th parameter starts $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 = $end } } #endregion Remove Parameter #region Rename Variables # If we're renaming variables or parameters if ($RenameVariable) { # Find all of the variable references $variablesToRename = @($ScriptBlock.Ast.FindAll({ param($ast) if ($ast -isnot [Management.Automation.Language.VariableExpressionast]) { return $false } if ($RenameVariable.Contains("$($ast.VariablePath)")) { return $true} return $false }, $true)) # Walk over each variable we have to rename. foreach ($var in $variablesToRename) { # $renameToValue = $RenameVariable["$($var.VariablePath)"] $replaceVariableText = if ($var.Splatted) { '@' + ($renameToValue -replace '^[\$\@]') } else { '$' + ($renameToValue -replace '^[\$\@]') } # Make a PSObject out of the replacement text $replaceVariableText = [PSObject]::New($replaceVariableText) # and add 'Inline' so that it renders correctly. $replaceVariableText.PSObject.Properties.Add([PSNoteProperty]::New('Inline', $true)) # then add our replacement to $astReplacement. $astReplacement[$var] = $replaceVariableText } } #endregion Rename Variables #region Replace AST # If we had any AST replacements if ($astReplacement.Count) { $myOffset = 0 $index = 0 # sort them by their start. $sortedReplacements = @( $astReplacement.GetEnumerator() | Sort-Object { $_.Key.Extent.StartOffset } | Select-Object -ExpandProperty Key ) # Then, walk over each replacement foreach ($item in $sortedReplacements) { # and turn it into a text range $start = $Text.IndexOf($item.Extent.Text, $myOffset) $end = $start + $item.Extent.Text.Length # then update the text replacements. $TextReplacement["$start,$end"] = $astReplacement[$item] $myOffset = $end } } #endregion Replace AST } #region Replace Text Spans # Sort the replacements by their starting position. $enumReplacements = @($TextReplacement.GetEnumerator() | Sort-Object { @($_.Key -split ',')[0] -as [int] }) $index = 0 $updatedText = @( # Walk thru each of the replacements for ($i = 0; $i -lt $enumReplacements.Count; $i++) { # get their start and end index $start, $end = $enumReplacements[$i].Key -split ',' -as [int[]] # (if neither was defined, keep moving). if (-not $start -and -not $end ) { continue } # If the start of the replacement is greater than the current index if ($start -gt $index) { # get all text between here and there. $Text.Substring($index, $start - $index) } # If the start was less than the index, we'd be replacing within what has already been replaced elseif ($start -lt $index) { continue # so continue. } # Determine where the line starts (for indenting purposes), $lineStartMatch = $lineStart.Match($text, $start) # perform the replacement, $enumReplacements[$i].Value | ReplaceWith -lineStartMatch $lineStartMatch # and update the index. $index = $end } # If there was any text remaining if ($index -lt $Text.Length) { $Text.Substring($index) # include it as-is. } ) -join '' #endregion Replace Text Spans # Update $text before we continue $text = $updatedText #region Replace Regions if ($RegionReplacement.Count) { # Region replacements are accomplished via a regular expression foreach ($regionName in $RegionReplacement.Keys) { $replacementReplacer = $RegionReplacement[$regionName] $RegionName = $RegionName -replace '\s', '\s' # We can create a Regex for each specific region, # thanks to [Irregular](https://github.com/StartAutomating/Irregular) $regionReplaceRegex = [Regex]::New(" [\n\r\s]{0,} # Preceeding whitespace \#region # The literal 'region' \s{1,} # followed by at least one space. (?<Name>$RegionName) (?<Content> (?:.|\s)+?(?= \z| ^\s{0,}\#endregion\s{1,}\k<Name> ) ) ^\s{0,}\#endregion\s{1,}\k<Name> ", 'Multiline,IgnorePatternWhitespace,IgnoreCase', '00:00:05') $RegexReplacement[$regionReplaceRegex] = $replacementReplacer } } #endregion Replace Regions #region Insert Before/After # If we have any -InsertBefore if ($InsertBefore.Count) { # Walk thru each insertion foreach ($kv in @($InsertBefore.GetEnumerator())) { if ( $kv.Value -is [string] -and # If the value was a string and -not $kv.Value.Contains('$&') # it did not include the substitution. ) { $kv.Value += '$&' # subsitute the match at the end. } # Add our insertion to the regular expression replacements. $RegexReplacement[$kv.Key] = $kv.Value } } # If we had any -InsertAfter if ($InsertAfter.Count) { # Walk thru each insertion foreach ($kv in @($InsertAfter.GetEnumerator())) { if ( $kv.Value -is [string] -and # If the value was a string and -not $kv.Value.Contains('$&') # it did not include the substitution. ) { $kv.Value = '$&' + $kv.Value # subsitute the match at the start. } # Add our insertion to the regular expression replacements. $RegexReplacement[$kv.Key] = $kv.Value } } #endregion Insert Before/After #region Replace Regex if ($RegexReplacement.Count) { foreach ($repl in $RegexReplacement.GetEnumerator()) { $replRegex = if ($repl.Key -is [Regex]) { $repl.Key } else { [Regex]::new($repl.Key,'IgnoreCase,IgnorePatternWhitespace','00:00:05') } $updatedText = $text = $replRegex.Replace($text, $repl.Value) } } #endregion Replace Regex if ($ScriptBlock) { $updatedScriptBlock = [ScriptBlock]::Create($updatedText) if ($Transpile) { $updatedScriptBlock | .>Pipescript } else { $updatedScriptBlock } } else { $updatedText } } } |