Rules
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The following guidelines ensure the consistency of the repository and allow some automated verifications and tasks.

* A rule shall be defined in a Python script, located in a sub-directory corresponding to a category.
* The name of the script is the pythonized name of the rule. For example, ``CamelCaseNaming`` is defined in
  ``naming/camel_case_naming.py``.
* The class defining the rule shall inherit from ``ansys.scade.design_rules.utils.Rule`` (TODO link).
  This is first meant for debugging and testing purposes. This class adds a few services to facilitate the design
  or customization of a rule.
* The ``id`` attribute of the rule must be ``id_<number>`` where ``<number>`` is a four digit number,
  for example ``id_0007``. The ``ansys.scade.design_rules.catalog.txt`` file lists all the existing rules, sorted
  by ``id``: When creating a new rule, use the next available id, that is the last one plus 1.
  The catalog is automatically updated by pre-commit hooks.
* The file shall be usable directly by *SCADE Metrics and Rules Checker*, at least for the examples or unit tests.
  This implies to:

  * Add the location of ``ansys.scade.design_rules.utils.Rule`` to the Python path at the beginning of the file:

    .. code::

       if __name__ == '__main__':
          # rule instantiated outside of a package
          from pathlib import Path
          import sys

          sys.path.append(str(Path(__file__).parent.parent.parent.parent.parent.resolve()))

  * Provide an instantiation with default parameters at the end of the file:

    .. code::

       if __name__ == '__main__':
          # rule instantiated outside of a package
          MyRule()