Text wrapping module for PowerShell

TextWrapping.psm1

#.SYNOPSIS
# Takes one or more lines of text that were produced by a text-wrapping algorithm
# and attempts to 'unwrap' them so that the line breaks that were added are removed.
#
#.DESCRIPTION
# Unwrapping text is an error-prone process, because it is impossible to know for sure
# whether or not a hard line break was intentional or added as a result of word-wrapping.
# This function makes several assumptions about wrapped text. For example, if there are
# spaces at the end of a line and the following line is not blank, it is assumed that the
# line was wrapped. If there is a space on a blank line, it is assumed that the line
# break is intentional and will not be unwrapped.
#
#.EXAMPLE
# Get-Help ForEach-Object | Select -Expand Description | Undo-TextWrapping
#
function Undo-TextWrapping
{
    [CmdletBinding()]
    [OutputType([String])]
    param (

        # The lines of text to unwrap, which may be supplied
        # on the pipeline.
        [Alias('Text')]
        [AllowEmptyString()]
        [Parameter(Position=1, Mandatory=$true, ValueFromPipeline=$true, ValueFromPipelineByPropertyName=$true)]
        [String[]]$InputString

    )

    begin {

        $Lines = @()
        $CurrentLine = ""

    }

    process {

        foreach ($Line in @($InputString -split '[\r\n|\r|\n]')) {

            # Skip this shit
            if ($Line -eq $Null) { continue }

            switch -regex ($Line) {

                # Special circumstances where we believe this to
                # definitely be a new line. (ie. list patterns,
                # space(s) at beginning of line, etc)
                '^(\s|\d+[\.\)\]]\s|\-\s)' {

                    # Commit the current line
                    if ($CurrentLine) {
                        $Lines += $CurrentLine.TrimEnd()
                    }

                    $CurrentLine = $Line

                    break

                }

                # Line is not blank
                '\S' {

                    $CurrentLine += $Line.TrimEnd() + ' '

                    break

                }

                # Blank or contains only spaces
                '^\s*$' {

                    # Commit the current line
                    if ($CurrentLine) {
                        $Lines += $CurrentLine.TrimEnd()
                    }

                    $CurrentLine = ''

                    break

                }

            }

        }

    }

    end {

        # If we have anything left over...
        if ($CurrentLine) {
            $Lines += $CurrentLine.TrimEnd()
        }

        for ($i=0; $i -lt $Lines.Count; $i++) {
            Write-Verbose $Lines[$i]
        }

        $Lines

    }

}

Export-ModuleMember -Function Undo-TextWrapping