Basic Cmdlet Build Script (No External Tools Needed)

build.ps1

<#PSScriptInfo 
.VERSION 1.0.0 
.GUID d6ffefc9-781f-4e1b-a46d-0238655151c7 
.AUTHOR endowdly 
.COMPANYNAME endowdly 
.COPYRIGHT 2019 
.TAGS 
.LICENSEURI 
.PROJECTURI 
.ICONURI 
.EXTERNALMODULEDEPENDENCIES 
.REQUIREDSCRIPTS 
.EXTERNALSCRIPTDEPENDENCIES 
.RELEASENOTES 
#>

<# 

.DESCRIPTION 
 A simple build script that can compile PowerShell Cmdlets without external tooling or references.

 Uses the native csharp compiler (csc.exe) located in the Framework directory.
 Uses 64bit tooling if available and then the highest version of framework tooling available. 
 Does not use additional toolkits installed by Visual Studio or the user.
 Uses the current session's PowerShell assembly. 
#> 

param ()

# Setup 
data Messages {
    @{
        Warning = @{
            DotSourced = 'This script was dot sourced. This is verboten to prevent session pollution!' 
            CannotInit = 'You are missing core Windows components! Cannot initialize.'
        }

        Information = @{
            DotSourced = 'RECOMMENDATION: Invoke this script using this call operator (&).'
            CannotClean = 'RECOMMENDATION: File is likely in use by another process. Close the process and try to build again.'
        } 

        Initialize = 'Initializing...'
        Initialized = 'Initialized'
        Cleaning = 'Cleaning... ' 
        Cleaned = 'Cleaned'
        Building = 'Building... '
        Built = 'Built'
        Fail = 'Fail'
        Nothing = 'Nothing to build!'
        LinkingCompiler = 'Linking compiler...'
        LinkedCompiler = 'Compiler linked'
        Source = 'Source directory exists'
        NewSource = 'Creating source directory...'
    } 
} 

data Build {
    @{
        FrameworkPaths = 'C:\Windows\Microsoft.NET\Framework*'
        Framework64 = 'C:\Windows\Microsoft.NET\Framework64'
        Framework = 'C:\Windows\Microsoft.NET\Framework64'
    }
}

$ErrorActionPreference = 'Stop' 
$WarningPreference = 'Continue'
$InformationPreference = 'Continue' 


function Get-Indent ($s, $n) { $s.Insert(0, (' ' * 2 * $n)) }


function Write-ColorOutput {
        param (
            $Object,
            [System.ConsoleColor] $ForegroundColor
        )

        $isHostReady =
            ($null -ne $Host.UI) -and
            ($null -ne $Host.UI.RawUI) -and
            ($null -ne $Host.UI.RawUI.ForegroundColor)

        if ($isHostReady -and ($null -ne $ForegroundColor)) {
            $originalColor = $Host.UI.RawUI.ForegroundColor
            $Host.UI.RawUI.ForegroundColor = $ForegroundColor
        }

        $Object 

        if ($null -ne $originalColor) {
            $Host.UI.RawUI.ForegroundColor = $originalColor 
        }
}


# Do not allow sourcing
$IsDotSourced = $MyInvocation.InvocationName -eq '.' -or $MyInvocation.Line -eq ''

if ($IsDotSourced) {
    Write-Warning $Messages.Warning.DotSourced
    Write-Information $Messages.Information.DotSourced -Tags Recommendation

    exit 1
} 

Push-Location $PSScriptRoot 
Write-Output $Messages.Initialize

try {
    Get-Command csc -CommandType Application | Out-Null 
    Write-Output (Indent $Messages.LinkedCompiler 1)
}
catch {
    Write-Output (Indent $Messages.LinkingCompiler 1)
    $IsFrameworkDir = Test-Path $Build.FrameworkPaths
    $Is64bit = Test-Path $Build.Framework64 

    if (!$IsFrameworkDir) {
        Write-PrettyOutput (Indent $Messages.Fail 1) -ForegroundColor Red
        Write-Host
        Write-Warning (Indent $Messages.Warning.CannotInit 1)

        exit 1
    } 

    $FrameworkDir = 
        if ($Is64bit) {
            $Build.Framework64
        }
        else {
            $Build.Framework
        }

    Get-ChildItem $FrameworkDir -Directory |
        Sort-Object Name |
        Select-Object -Last 1 |
        Get-ChildItem -Filter csc.exe |
        Set-Variable csc
    Set-Alias -Name csc -Value $csc.FullName
    Write-Output (Indent $Messages.LinkedCompiler 1)
}

if (Test-Path src) {
    Write-Output (Indent $Messages.Source 1)
}
else {
    Write-Output (Indent $Messages.NewSource 1)
    New-Item src -ItemType Directory | Out-Null
    Write-Output (Indent $Messages.Source 1)
}

Write-ColorOutput (Indent $Messages.Initialized 1) -ForegroundColor Green
Write-Host
Write-Output $Messages.Cleaning

try {
    Join-Path $PSScriptRoot out -OutVariable OutputDirectory | 
        Get-ChildItem -Recurse -File -OutVariable CleanedFiles | 
        ForEach-Object {
            Write-Information (Indent $_.Name 1)
            Remove-Item $_.FullName -Force
        }
}
catch {
    Write-ColorOutput (Indent $Messages.Fail 1) -ForegroundColor Red
    Write-Host
    Write-Information $Messages.Information.CannotClean

    exit 1
}

New-Item out -ItemType Directory -Force | Out-Null
Write-ColorOutput (Indent $Messages.Cleaned 1) -ForegroundColor Green
Write-Host

# Get every src file 
Write-Information $Messages.Building
Get-ChildItem src -Filter *.cs -OutVariable SourceFiles | Foreach-Object { Write-Information (Indent $_.Name 1) } 

if (!$SourceFiles) {
    Write-ColorOutput (Indent $Messages.Nothing 1) -ForegroundColor Yellow

    exit 0
}

# Get Assembly Reference
$PSAssemblyPath = [psobject].Assembly.Location
$TargetName = Split-Path $PSScriptRoot -Leaf
$OutPath = Join-Path out "${TargetName}.dll"

# Compiler Options
$CscArguments = @(
    "/reference:$PSAssemblyPath"
    "/out:$OutPath"
    '/target:library'
    '/nologo'
)

$Result = & csc $CscArguments $SourceFiles.FullName 2>&1

if (!$?) {
    Write-ColorOutput (Indent $Messages.Fail 1) -ForegroundColor Red
    Write-Host 

    $Result | Foreach-Object { Write-ColorOutput $_ -ForegroundColor Red }

    exit 1
} 
else {
    Write-ColorOutput (Indent $Messages.Built 1) -ForegroundColor Green
    Write-Host
} 

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