kapitan lint incorrectly reports no usage for classes with variables

[gburiola]

Reclass allows using references in class names (docs)

This works fine when expanding the inventory with kapitan inventory.

However, when you run kapitan lint, it fails to identify that a given classes is being used through a reference.

Example inventory

./classes/common.yaml
parameters:
  env: prod

--------------------

./classes/app/init.yaml
classes:
  - app.${env}

--------------------

./classes/app/prod.yaml
parameters:
  myapp:
   replicas: 2

--------------------

./targets/prod-target1.yaml
classes:
  - common
  - app

parameters:

kapitan inventory

$ kapitan inventory
__reclass__:
  timestamp: Mon May  1 09:12:45 2023
applications: {}
classes:
  app:
    - prod-target1
  app.${env}:
    - prod-target1
  common:
    - prod-target1
nodes:
  prod-target1:
    __reclass__:
      environment: base
      name: prod-target1
      node: prod-target1
      timestamp: Mon May  1 09:12:45 2023
      uri: yaml_fs:///src/inventory/targets/prod-target1.yaml
    applications: []
    classes:
      - app.${env}
      - common
      - app
    environment: base
    exports: {}
    parameters:
      _reclass_:
        environment: base
        name:
          full: prod-target1
          parts:
            - prod-target1
          path: prod-target1
          short: prod-target1
      env: prod
      myapp:
        replicas: 2

kapitan lint

incorrectly reports that class app.prod is not used.
it's used, but using a variable reference

$ kapitan lint

Running yamllint on all inventory files...

.yamllint not found. Using default values

Checking for orphan classes in inventory...

No usage found for the following 1 classes:
{'app.prod'}

[github-actions]

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