I have an Azure DevOps pipeline that executes a Powershell task to create artifacts for each changed file after a pull request is submitted. However, I am not able to return modified/new files in order to create these artifacts. When I test locally I have no problem grabbing the modified file name, but within the pipeline itself the returned result is blank/empty:

$changes = git diff --name-only --relative --diff-filter=M origin/master --name-only -- .

Full .yml Code:

trigger:
- master

pool:
  vmImage: windows-latest

jobs:
- job: get_changed_files
  steps:  
   - task: [email protected]
     inputs:
       targetType: 'inline'
       script: |
         $targetfolder = "$(Build.StagingDirectory)" + "/"
         
         function CopyFiles{
             param( [string]$source )
         
             $target = $targetfolder + $source
         
             New-Item -Force $target
             copy-item $source $target -Force
         }
         $changes = git diff --name-only --relative --diff-filter=M origin/master --name-only -- .
         write-host "test"
         $changes
         if ($changes -is [string]){ CopyFiles $changes }
         else
         {
             if ($changes -is [array])
             {       
                 foreach ($change in $changes){ CopyFiles $change }
             }
         }
   - task: [email protected]
     inputs:
      pathToPublish: $(Build.StagingDirectory)
      artifactName: MyChangedFiles