Compress-ScriptBlock.ps1

function Compress-ScriptBlock {
    [CmdletBinding()]
    [Alias('minify')]
    [OutputType([scriptblock])]
    param (
        [Parameter(Mandatory, Position = 0, ValueFromPipeline)]
        [ValidateNotNullOrEmpty()]
        [scriptblock]
        $ScriptBlock
    )

    $StringBuilder = New-Object System.Text.StringBuilder
    $StrSb = $ScriptBlock.ToString()
    $AliasList = Get-Alias

    $Tokens = [System.Management.Automation.PSParser]::Tokenize($ScriptBlock, [ref]$null)
    foreach ($Token in $Tokens) {
        switch ($Token.Type) {
            'Comment' {
                break
            }

            'NewLine' {
                if ($StringBuilder.Length -eq 0) { }
                elseif ($StringBuilder.Chars($StringBuilder.Length - 1) -in ("`n", ';', '{', '(')) { }
                else {
                    [void]$StringBuilder.Append("`n")
                }
                break
            }

            'GroupEnd' {
                if (($StringBuilder.Length -ne 0) -and ($StringBuilder.Chars($StringBuilder.Length - 1) -in ("`n", ';'))) {
                    [void]$StringBuilder.Remove($StringBuilder.Length - 1, 1)
                }

                [void]$StringBuilder.Append($Token.Content)
                break
            }

            'Variable' {
                [void]$StringBuilder.Append($StrSb.Substring($Token.Start, $Token.Length))
                break
            }

            'Keyword' {
                switch ($Token.Content) {
                    { $_ -in ('catch', 'finally', 'elseif', 'else', 'until') } {
                        if (($StringBuilder.Length -ne 0) -and ($StringBuilder.Chars($StringBuilder.Length - 1) -in ("`n", ';'))) {
                            [void]$StringBuilder.Remove($StringBuilder.Length - 1, 1)
                        }
                        [void]$StringBuilder.Append($Token.Content)
                        break
                    }

                    'while' {
                        if (($StringBuilder.Length -ne 0) -and ($StringBuilder.Chars($StringBuilder.Length - 1) -in ("`n", ';'))) {
                            [void]$StringBuilder.Remove($StringBuilder.Length - 1, 1)
                            [void]$StringBuilder.Append("`n")
                        }
                        [void]$StringBuilder.Append($Token.Content)
                        break
                    }

                    'in' {
                        [void]$StringBuilder.Append(' ')
                        [void]$StringBuilder.Append($Token.Content)
                        [void]$StringBuilder.Append(' ')
                        break
                    }

                    { $_ -in ('return', 'exit') } {
                        [void]$StringBuilder.Append($Token.Content)
                        [void]$StringBuilder.Append(' ')
                        break
                    }

                    Default {
                        [void]$StringBuilder.Append($Token.Content)
                    }
                }
            }

            'Command' {
                if ($Alias = $AliasList | Where-Object { $_.Definition -eq $Token.Content }) {
                    $ShortestAlias = $Alias | Select-Object -ExpandProperty Name | Sort-Object { $_.Length } | Select-Object -First 1
                    [void]$StringBuilder.Append($ShortestAlias)
                }
                else {
                    [void]$StringBuilder.Append($Token.Content)
                }
                [void]$StringBuilder.Append(' ')
                break
            }

            'CommandArgument' {
                [void]$StringBuilder.Append(' ')
                [void]$StringBuilder.Append($Token.Content)
                [void]$StringBuilder.Append(' ')
                break
            }

            'CommandParameter' {
                [void]$StringBuilder.Append(' ')

                $Content = switch ($Token.Content) {
                    '-Debug' { '-db'; break }
                    '-ErrorAction' { '-ea'; break }
                    '-ErrorVariable' { '-ev'; break }
                    '-InformationAction' { '-infa'; break }
                    '-InformationVariable' { '-iv'; break }
                    '-OutVariable' { '-ov'; break }
                    '-OutBuffer' { '-ob'; break }
                    '-PipelineVariable' { '-pv'; break }
                    '-Verbose' { '-vb'; break }
                    '-WarningAction' { '-wa'; break }
                    '-WarningVariable' { '-wv'; break }
                    Default { $Token.Content }
                }

                [void]$StringBuilder.Append($Content)

                if ($Content[-1] -ne ':') {
                    [void]$StringBuilder.Append(' ')
                }
                break
            }

            'Operator' {
                if ($Token.Content -eq '-not') {
                    [void]$StringBuilder.Append('!')

                }
                else {
                    [void]$StringBuilder.Append($Token.Content)
                }
                break
            }

            'String' {
                [void]$StringBuilder.Append($StrSb.Substring($Token.Start, $Token.Length))
                break
            }

            'LineContinuation' {
                break
            }

            Default {
                [void]$StringBuilder.Append($Token.Content)
            }
        }
    }

    if ($StringBuilder.Length -ne 0) {
        if ($StringBuilder.Chars($StringBuilder.Length - 1) -in ("`n", ';')) {
            [void]$StringBuilder.Remove($StringBuilder.Length - 1, 1)
        }
    }

    [scriptblock]::Create($StringBuilder.ToString())
}