Rule with null is interpreted as empty string

[dbrumann]

Assuming you have a configuration with a ruleset where a layer does not define any dependencies, e.g. this one:

paths:
  - ./src
exclude_files:
  - '#.*test.*#'
layers:
  - name: Controllers
    collectors:
      - type: className
        regex: ^App\\Controller\\.*
ruleset:
  Controllers: ~ # or its equivalent: null

This will produce the following error:

In ArrayNode.php line 260:

  Invalid type for path "deptrac.ruleset.Controllers". Expected "array", but got "string"

The current workaround is to assign an empty list, i.e. Controllers: [], but it would be nice, if null/ ~ would work as well.

[dbrumann]

I can't reproduce this anymore, so closed for now