Functions/GenXdev.Coding.Templating/Remove-DoubleEmptyLines.ps1
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<############################################################################## Part of PowerShell module : GenXdev.Coding.Templating Original cmdlet filename : Remove-DoubleEmptyLines.ps1 Original author : René Vaessen / GenXdev Version : 3.28.2026 ################################################################################ Copyright (c) 2026 René Vaessen / GenXdev Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. ################################################################################> ################################################################################ <# .SYNOPSIS Removes double (consecutive) empty lines from a code string, optionally reformatting the output. .DESCRIPTION Cleans up source code or text by collapsing consecutive blank lines into a single empty line. This improves readability and follows common code formatting conventions. When the -Reformat switch is specified, additional formatting rules are applied to normalize the code structure. .PARAMETER code The source code or text string to process. Multiple consecutive empty lines within this text will be collapsed to a single empty line. .PARAMETER Reformat When specified, applies additional formatting rules beyond just removing double empty lines, such as normalizing indentation and spacing patterns. .EXAMPLE $cleanCode = $sourceCode | Remove-DoubleEmptyLines Pipes source code through the function to remove consecutive blank lines. .EXAMPLE Remove-DoubleEmptyLines -code $sourceCode -Reformat Removes double empty lines and applies additional formatting. #> function Remove-DoubleEmptyLines { [CmdletBinding()] [Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseSingularNouns', '')] [Diagnostics.CodeAnalysis.SuppressMessageAttribute('PSUseShouldProcessForStateChangingFunctions', '')] [OutputType([string])] param( ########################################################################### [Parameter( Mandatory = $true, Position = 0, ValueFromPipeline = $false, HelpMessage = 'The source code or text string to process for ' + 'double empty line removal' )] [string] $code, ########################################################################### [Parameter( Mandatory = $false, ValueFromPipeline = $false, HelpMessage = 'Apply additional formatting rules beyond ' + 'double empty line removal' )] [switch] $Reformat ) begin { $sb = [System.Text.StringBuilder]::new() } process { $lines = $code.Replace("`r", "`n").Split("`n", [System.StringSplitOptions]::RemoveEmptyEntries); $lastNonEmptyLine = [string]::Empty $previousLastNonEmptyLine = [string]::Empty $lastLineWasEmpty = $false $hadSameLineStart = $false for ($i = 0; $i -lt $lines.Count; $i++) { $line = $lines[$i].TrimEnd() $isEmptyLine = [string]::IsNullOrWhiteSpace($line) $isOpeningBrace = $line.Trim().EndsWith("{") $isClosingBrace = $line.Trim().EndsWith("}") $isLastLine = ($i -eq $lines.Count - 1) # determine if next line is empty or closing brace $nextLineIsEmpty = $false $nextLineIsClosingBrace = $false if ($i + 1 -lt $lines.Count) { $nextLine = $lines[$i + 1].TrimEnd() $nextLineIsEmpty = [string]::IsNullOrWhiteSpace($nextLine) $nextLineIsClosingBrace = $nextLine.Trim().StartsWith("}") } $previousLastNonEmptyLine = $lastNonEmptyLine $lastNonEmptyLine = if (-not $isEmptyLine) { $line } else { $lastNonEmptyLine } # handle empty lines if ($isEmptyLine) { # skip empty lines at the end of the file if ($isLastLine) { continue } # rule 2: never output empty line before closing brace if ($nextLineIsClosingBrace) { # skip this empty line continue } # rule 3: never output two empty lines in a row if ($lastLineWasEmpty) { # skip this empty line continue } # output single empty line $null = $sb.Append("`r`n") $lastLineWasEmpty = $true } else { if ($Reformat) { $hadSameLineStart = $false if ($previousLastNonEmptyLine.Trim().Length -gt 4 -and $lastNonEmptyLine.Trim().Length -gt 4) { if ($previousLastNonEmptyLine.Trim().Substring(0, 4) -eq $lastNonEmptyLine.Trim().Substring(0, 4)) { while ($sb.Length -ge 0 -and ("`r`n `t".IndexOf($sb[$sb.Length - 1]) -ge 0)) { $null = $sb.Remove($sb.Length - 1, 1) } $null = $sb.Append("`r`n") $hadSameLineStart = $true } } if ((-not $lastLineWasEmpty) -and (-not $hadSameLineStart) -and (-not $isOpeningBrace) -and (-not $isLastLine) -and (-not $isClosingBrace)) { $null = $sb.Append("`r`n") } } if ($isOpeningBrace -and ((-not $nextLineIsEmpty) -or ($nextLine.Trim().EndsWith("{"))) -and (-not $isLastLine)) { $null = $sb.Append("`r`n") } # output non-empty line if ($isLastLine) { $null = $sb.Append($line) } else { $null = $sb.Append($line).Append("`r`n") } $lastLineWasEmpty = $false if ($isOpeningBrace -and (-not $nextLineIsEmpty) -and -not $isLastLine) { $null = $sb.Append("`r`n") $lastLineWasEmpty = $true } } } } end { Microsoft.PowerShell.Utility\Write-Output ($sb.ToString()) } } ################################################################################ |