Different string substitution behavior for tags and flavor

[sparanoid]

Behaviour

Steps to reproduce this issue

On tags:

tags: |
  type=ref,event=branch,prefix=${{ !startsWith(matrix.php, '8-fpm') && ' ' || format('{0}-', steps.prefix.outputs.ref) }}

Docker meta output:

Docker tags
  ***/php-fpm:master
  ghcr.io/***/php-fpm:master

On flavor:

flavor: |
  prefix=${{ !startsWith(matrix.php, '8-fpm') && ' ' || format('{0}-', steps.prefix.outputs.ref) }},onlatest=true

Expected behaviour

Docker tags
  ***/php-fpm:latest
  ghcr.io/***/php-fpm:latest

Actual behaviour

Docker meta output:

Docker tags
  ***/php-fpm: latest
  ghcr.io/***/php-fpm: latest

Configuration

• Repository URL (if public): https://github.com/sparanoid/docker-php-fpm/runs/3905185170

[crazy-max]

@sparanoid

As I can see in your workflow a space is added to the prefix:

Looks related to your condition && ' '.

I guess we should also trim the value for good measure and avoid this kind of behavior.