src/public/Format-ScriptReduceLineLength.ps1
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function Format-ScriptReduceLineLength { <# .SYNOPSIS Attempt to shorten long lines if possible. .DESCRIPTION Attempt to shorten long lines if possible. .PARAMETER Code Multiline or piped lines of code to process. .PARAMETER Length Number of characters to shorten long lines to. Default is 115 characters as this is best practice. .PARAMETER SkipPostProcessingValidityCheck After modifications have been made a check will be performed that the code has no errors. Use this switch to bypass this check (This is not recommended!) .EXAMPLE PS > $testfile = 'C:\temp\test.ps1' PS > $test = Get-Content $testfile -raw PS > $test | Format-ScriptReduceLineLength | clip Description ----------- Takes C:\temp\test.ps1 as input, formats as the function defines and places the result in the clipboard to be pasted elsewhere for review. .NOTES Author: Zachary Loeber Site: http://www.the-little-things.net/ Requires: Powershell 3.0 Version History 1.0.0 - Initial release #> [CmdletBinding()] param( [parameter(Position=0, Mandatory=$true, ValueFromPipeline=$true, HelpMessage='Lines of code to process.')] [AllowEmptyString()] [string[]]$Code, [parameter(Position=1, HelpMessage='Number of characters to shorten long lines to. Default is 115 characters.')] [int]$Length = 115, [parameter(Position=2, HelpMessage='Bypass code validity check after modifications have been made.')] [switch]$SkipPostProcessingValidityCheck ) begin { if ($script:ThisModuleLoaded -eq $true) { Get-CallerPreference -Cmdlet $PSCmdlet -SessionState $ExecutionContext.SessionState } $FunctionName = $MyInvocation.MyCommand.Name Write-Verbose "$($FunctionName): Begin." $Codeblock = @() $ParseError = $null $Tokens = $null } process { $Codeblock += $Code } end { $ScriptText = $Codeblock | Out-String Write-Verbose "$($FunctionName): Attempting to parse AST." $AST = [System.Management.Automation.Language.Parser]::ParseInput($ScriptText, [ref]$Tokens, [ref]$ParseError) if($ParseError) { $ParseError | Write-Error throw "$($FunctionName): Will not work properly with errors in the script, please modify based on the above errors and retry." } $LongLines = @() $LongLinecount = 0 $SplitScriptText = @($ScriptText -split "`r`n") $OutputScript = @() for($t = 0; $t -lt $SplitScriptText.Count; $t++) { [string]$CurrentLine = $SplitScriptText[$t] Write-Debug "Line - $($t): $CurrentLine" if ($CurrentLine.Length -gt $Length) { $CurrentLineLength = $CurrentLine.Length # find spaces at the beginning of our line. if ($CurrentLine -match '^([\s]*).*$') { $Padding = $Matches[1] $PaddingLength = $Matches[1].length } else { $Padding = '' $PaddingLength = 0 } $AdjustedLineLength = $Length - $PaddingLength $AllTokensOnLine = $Tokens | Get-TokensOnLineNumber -LineNumber ($t+1) $BreakableTokens = @($AllTokensOnLine | Get-BreakableTokens) $DesiredBreakPoints = [Math]::Round($SplitScriptText[$t].Length / $AdjustedLineLength) if ($BreakableTokens.Count -gt 0) { Write-Debug "$($FunctionName): Total String Length: $($CurrentLineLength)" Write-Debug "$($FunctionName): Breakpoint Locations: $($BreakableTokens.Extent.EndColumnNumber -join ', ')" Write-Debug "$($FunctionName): Padding: $($PaddingLength)" Write-Debug "$($FunctionName): Desired Breakpoints: $($DesiredBreakPoints)" if (($BreakableTokens.Count -eq 1) -or ($DesiredBreakPoints -ge $BreakableTokens.Count)) { # if we only have a single breakpoint or the total breakpoints available is equal or less than our desired breakpoints # then simply split the line at every breakpoint. $TempBreakableTokens = @() $TempBreakableTokens += 0 $TempBreakableTokens += $BreakableTokens | Foreach { $_.Extent.EndColumnNumber - 1 } $TempBreakableTokens += $CurrentLine.Length for($t2 = 0; $t2 -lt $TempBreakableTokens.Count - 1; $t2++) { $OutputScript += $Padding + ($CurrentLine.substring($TempBreakableTokens[$t2],($TempBreakableTokens[$t2 + 1] - $TempBreakableTokens[$t2]))).Trim() } } else { # Otherwise we need to selectively break the lines down $TempBreakableTokens = @(0) # Start at the beginning always # We need to adjust our segment length to account for padding we will be including into each segment # to keep the resulting output aligned at the same column it started in. $TotalAdjustedLength = $CurrentLineLength + ($DesiredBreakPoints * $PaddingLength) $SegmentMedianLength = [Math]::Round($TotalAdjustedLength/($DesiredBreakPoints + 1)) $TokenStartOffset = 0 # starting at the beginning of the string for($t2 = 0; $t2 -lt $BreakableTokens.Count; $t2++) { $TokenStart = $BreakableTokens[$t2].Extent.EndColumnNumber $NextTokenStart = $BreakableTokens[$t2 + 1].Extent.EndColumnNumber if ($t2 -eq 0) { $TokenSize = $TokenStart } else { $TokenSize = $TokenStart - $BreakableTokens[$t2 - 1].Extent.EndColumnNumber } $NextTokenSize = $NextTokenStart - $TokenStart if ((($TokenStartOffset + $TokenSize) -ge $SegmentMedianLength) -or ($NextTokenSize -ge ($SegmentMedianLength - $TokenSize)) -or (($TokenStartOffset + $TokenSize + $NextTokenSize) -gt $SegmentMedianLength)) { $TempBreakableTokens += $BreakableTokens[$t2].Extent.EndColumnNumber - 1 $TokenStartOffset = 0 } else { $TokenStartOffset = $TokenStartOffset + $TokenSize } } $TempBreakableTokens += $CurrentLine.Length for($t2 = 0; $t2 -lt $TempBreakableTokens.Count - 1; $t2++) { Write-Verbose "$($FunctionName): Inserting break in line $($t) at column $($TempBreakableTokens[$t2])" $OutputScript += $Padding + ($CurrentLine.substring($TempBreakableTokens[$t2],($TempBreakableTokens[$t2 + 1] - $TempBreakableTokens[$t2]))).Trim() } } } else { # This line is long and has no plausible breaking points, oh well. $OutputScript += $CurrentLine } } else { # This line doesn't need to be shortened. $OutputScript += $CurrentLine } } # Validate our returned code doesn't have any unintentionally introduced parsing errors. if (-not $SkipPostProcessingValidityCheck) { if (-not (Format-ScriptTestCodeBlock -Code $ScriptText)) { throw "$($FunctionName): Modifications made to the scriptblock resulted in code with parsing errors!" } } $OutputScript Write-Verbose "$($FunctionName): End." } } |