task.ps1

$packageName = Get-VstsInput -Name 'packageName' -Require
$maxIncrement = Get-VstsInput -Name 'maxIncrement' -Require
$pipelineVariable = Get-VstsInput -Name 'pipelineVariable' -Require

Write-Host "The Package in use is: " $packageName
Write-Host "The Max Increment version is: " $maxIncrement

#Add Package Source
Write-Host "Adding Nuget Package Source"
Register-PackageSource -Name NuGet -Location https://www.nuget.org/api/v2 -ProviderName NuGet

#Get the current version for the Package
$currentVersion = Find-Package $packageName -Source NuGet | Select-Object -ExpandProperty Version

#Split version
$Major = $currentVersion.Split(".")[0] -as [int]
$Minor = $currentVersion.Split(".")[1] -as [int]
$Patch = $currentVersion.Split(".")[2] -as [int]

#Set new/next version of Package
$newVersion;

if(($Patch + 1) -eq $maxIncrement) {

  #Increment the Minor version and reset patch version to 0
  Write-Host "Patch version value has been reached the Max Increment value supplied."
  Write-Host "Reset the Patch version to 0 and Increment the Minor version by 1"

  $Minor = ($Minor = + 1);
  $Patch = 0;
}else {

  #Increment the Patch version
  Write-Host "Patch version value has not been reached the Max Increment value supplied. Only Increment Patch version."

  $Patch = ($Patch + 1);
}

$newVersion = ($Major, $Minor, $Patch) -Join "."

# Output the message to the log.
Write-Host "Old Version of Package: " $currentVersion
Write-Host "New Version for Package: " $newVersion

Write-Host "Set environment variable to ($newVersion)"

# Output the new version to be used by the subsequent tasks
Write-Output "##vso[task.setvariable variable=$pipelineVariable;]$newVersion"

Write-Host "New Package version $newVersion"