function Compare-Folders {
    [CmdletBinding()]
    [OutputType([string[]])]
    param (
        [switch]$FilenamesOnly,
        [Parameter(Position = 0)]
        [string]$CompareFrom,
        [Parameter(Position = 1)]
        [string]$CompareTo,
        [int]$SurroundingLines = 2,
        [switch]$OnlyNewFrom,
        [switch]$OnlyNewTo,
        [string[]]$ExcludedPaths = @("bin","obj","dist","packages","TestResults","Debug","Release")
    )

    $directorySeparator = [IO.Path]::DirectorySeparatorChar
    if (Test-IsWindowsPlatform) {
        $directorySeparator = [IO.Path]::DirectorySeparatorChar + [IO.Path]::DirectorySeparatorChar
    }
<#
    $excludedPathFull = @()
    foreach ($path in $ExcludedPaths) {
        $excludedPathFull = "{0}$path{0}" -f $directorySeparator
    }
#>

    $CompareFrom = Resolve-Path $CompareFrom
    $CompareTo = Resolve-Path $CompareTo

    $filesFrom = (Get-ChildItem -Path $CompareFrom -Recurse -File)
    $filesTo = (Get-ChildItem -Path $CompareTo -Recurse -File)

    if ($FilenamesOnly) {
        return (Compare-Object $filesFrom $filesTo)
    }

    $pathsFrom = @()
    $pathsTo = @()

    # $filesFrom[22].FullName.Replace($CompareFrom,"")
    # $filesFrom[22].FullName.Replace($CompareFrom,"") -split $directorySeparator
    # return

    foreach ($file in $filesFrom) {
        $path = $file.FullName.Replace($CompareFrom,"")
        $skipAdd = $false
        [string[]]$split = ($path -split $directorySeparator)
        if (([System.Linq.Enumerable]::Intersect($split,$ExcludedPaths)).Count -gt 0) {
            $skipAdd = $true
        }
        if (!$skipAdd) {
            $pathsFrom += $path
        }
    }

    foreach ($file in $filesTo) {
        $path = $file.FullName.Replace($CompareTo,"")
        $skipAdd = $false
        [string[]]$split = ($path -split $directorySeparator)
        # if ($path.IndexOf($excludedPath) -ne -1) {
        if (([System.Linq.Enumerable]::Intersect($split,$ExcludedPaths)).Count -gt 0) {
            $skipAdd = $true
        }
        if (!$skipAdd) {
            $pathsTo += $path
        }
    }

    $resultLines = @()
    $resultFiles = @()

    if ($OnlyNewFrom) {
        Compare-Object -ReferenceObject $pathsFrom -DifferenceObject $pathsTo | ? { $_.SideIndicator -eq "<="}
    } elseif ($OnlyNewTo) {
        Compare-Object -ReferenceObject $pathsFrom -DifferenceObject $pathsTo | ? { $_.SideIndicator -eq "=>"}
    } else {
        $paths = $pathsFrom + $pathsTo | Sort-Object -Unique
        foreach ($file in $paths) {
            $pathFromContains = $pathsFrom -contains $file
            $pathToContains = $pathsTo -contains $file
            $fromPath = (Join-Path $CompareFrom $file)
            $toPath = (Join-Path $CompareTo $file)
            if ($pathFromContains -and $pathToContains) {
                if ((Get-Item -Path $fromPath).Length -ne (Get-Item -Path $toPath).Length) {
                    $lines = Compare-File -CompareFrom $fromPath -CompareTo $toPath -Porcelain -SurroundingLines $SurroundingLines
                    if ($lines.Count -gt 0) {
                        $resultLines += $lines
                        $resultLines += "`n`n"
                    }
                }
            } else {
                $resultFiles += "File [$file] only present on $(if($pathFromContains) {$CompareFrom} else {$CompareTo})"
            }
        }
        $resultFiles
        $resultLines
    }
}