build-chocolatey.ps1

# build-chocolatey.ps1: Builds a Chocolatey package for Yarn, and optionally pushes it to 
# Chocolatey.org (if the -Publish flag is passed).

param(
  [switch] $Publish = $false
)

$ErrorActionPreference = 'Stop'; # stop on all errors

$latest_version = [String](Invoke-WebRequest -Uri https://yarnpkg.com/latest-version)
$latest_chocolatey_version = (Find-Package -Name Yarn).Version

if ([Version]$latest_chocolatey_version -ge [Version]$latest_version) {
  Write-Output ('Current version ({0}) is the latest' -f $latest_chocolatey_version)
  Exit
}

Write-Output ('Latest version is {0}, version on Chocolatey is {1}. Updating...' -f $latest_version, $latest_chocolatey_version)

if (-Not (Test-Path artifacts)) {
  mkdir artifacts
}
# Remove any existing Chocolatey packages, we don't care about them any more
rm artifacts/*.nupkg

# Download the installer so we can compute its hash
# Keep this in sync with chocolateyInstall.ps1.in
# This is intentionally not using /latest.msi to ensure the URL used by the Chocolatey package is valid.
$url = "https://yarnpkg.com/downloads/$latest_version/yarn-$latest_version.msi"
$installer_file = [IO.Path]::GetTempFileName()
Invoke-WebRequest -Uri $url -OutFile $installer_file

$hash = (Get-FileHash -Path $installer_file -Algorithm SHA256).Hash

# Replace placeholders in chocolateyInstall.ps1
(Get-Content .\resources\win-chocolatey\tools\chocolateyinstall.ps1.in) `
  -replace '{VERSION}', $latest_version `
  -replace '{CHECKSUM}', $hash | 
  Set-Content .\resources\win-chocolatey\tools\chocolateyinstall.ps1
  
choco pack .\resources\win-chocolatey\yarn.nuspec --version $latest_version
mv *.nupkg artifacts

if (!$Publish) {
  Write-Output 'Not publishing the package - Use "-Publish" flag if you want to publish it'
  Exit
}

$filename = ls artifacts\*.nupkg | % FullName
choco push $filename