set_vs_vars.ps1

#
# Find vswhere (installed with recent Visual Studio versions).
#
If ($vsWhere = Get-Command "vswhere.exe" -ErrorAction SilentlyContinue) {
  $vsWhere = $vsWhere.Path
} ElseIf (Test-Path "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe") {
  $vsWhere = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe"
}
 Else {
  Write-Error "vswhere not found. Aborting." -ErrorAction Stop
}
Write-Host "vswhere found at: $vsWhere" -ForegroundColor Yellow


#
# Get path to Visual Studio installation using vswhere.
#
$vsPath = &$vsWhere -latest -version "[16.0,17.0)" -products * `
 -requires Microsoft.Component.MSBuild `
 -property installationPath
If ([string]::IsNullOrEmpty("$vsPath")) {
  Write-Error "Failed to find Visual Studio 2019 installation. Aborting." -ErrorAction Stop
}
Write-Host "Using Visual Studio installation at: ${vsPath}" -ForegroundColor Yellow


#
# Make sure the Visual Studio Command Prompt variables are set.
#
If (Test-Path env:LIBPATH) {
  Write-Host "Visual Studio Command Prompt variables already set." -ForegroundColor Yellow
} Else {
  # Load VC vars
  Push-Location "${vsPath}\VC\Auxiliary\Build"
  cmd /c "vcvarsall.bat x64&set" |
    ForEach-Object {
      If ($_ -match "=") {
        $v = $_.split("="); Set-Item -Force -Path "ENV:\$($v[0])" -Value "$($v[1])"
      }
    }
  Pop-Location
  Write-Host "Visual Studio Command Prompt variables set." -ForegroundColor Yellow
}