Azure pipeline set displayname of task based on condition - azure-devops

Question

In the build pipeline I have a job with a powershell script setting the applicatiuon name based on a variable like this:
$applicationName = If ('$(configuration)' -eq 'Release') { 'Appname' } Else { 'Appname-Test' }
Write-Host "##vso[task.setvariable variable=applicationName]$applicationName"
I try to set the display name of the PublishBuildArtifacts#1 variable to the variable like this:
- task: PublishBuildArtifacts#1
displayName: $[variables.applicationName] # runtime variable
But this literally displays $[variables.applicationName] instead of the variable value. How can I change the displayname of a task based on a variable?

Answer 1

You can just use the variable in this way: $(variableName). for example:
pool:
vmImage: 'windows-latest'
variables:
test: "SomeValue"
steps:
- task: PowerShell#2
inputs:
targetType: 'inline'
script: 'Write-Host "Hello World"'
displayName: "The variable $(test)"
The result is:

Answer 2

It doesn't appear that this is currently possible. In both issues I found, they described this as a feature request.
https://github.com/MicrosoftDocs/azure-devops-docs/issues/2327
https://github.com/microsoft/azure-pipelines-yaml/issues/45

Answer 3

I assume ${{..}} is the way to go. You know the configuration at compile time, so you can create the app name at compile time.
variables:
${{ if eq(variables.configuration, 'Release') }}:
applicationName: 'Appname'
${{ if ne(variables.configuration, 'Release') }}:
applicationName: 'Appname-Test'
- task: PublishBuildArtifacts#1
displayName: ${{ variables.applicationName }}