Docker plugin does not expand variable for "privileged"

[LorenzoBettini]

I'd like to pass a variable for the privileged part e.g.,

platforms:
  - name: arch-instance
    image: arch-ansible
    platform: ${DOCKER_DEFAULT_PLATFORM:-linux/amd64}
    dockerfile: ../docker/Dockerfile
    build_image: true
...
    privileged: ${DOCKER_PRIVILEGED:-False}

During TASK [Discover local Docker images] the variable seems to be expanded correctly:

TASK [Discover local Docker images] ********************************************
ok: [localhost] => (item={'diff': [], '... 'platform': 'linux/amd64', 'privileged': False, ...

But then it fails later:

TASK [Wait for instance(s) creation to complete] *******************************
failed: ...
"msg": "argument 'privileged' is of type <class 'str'> and we were unable to convert to bool:
The value '${DOCKER_PRIVILEGED:-False}' is not a valid boolean. 
Valid booleans include: 'on', 'yes', 1, 0, '0', 'false', 'no', '1', 'f', 'off', 'y', 'true', 't', 'n'"...

[apatard]

I'm not sure it's an issue with the plugin since it's not responsible for the variable interpolation.
Anyway, I failed to reproduce it with a quick test. Can you please provide a more detailed reproducer and the output of molecule --version ?

[LorenzoBettini]

@apatard I'll try to recreate a reproducer with the latest molecule docker plugin.
In the meantime, could you please share your quick test?
Is it based on a pre-built image or a custom Dockerfile (the latter is my context)

[apatard]

sorry, too late, I've already deleted it and it was based on pre-built image. pre-built or not should not change anything I guess. The only place where privileged is used is in the task "Create molecule instance(s)", which is used in both case.

[apatard]

Is this bug still there ?

[LorenzoBettini]

I gave up using that option with a variable... the last time I tried the bug was there.