Metrics#

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

  • A metric shall be defined in a Python script, located in the metrics sub-directory.

  • The name of the script is the pythonized name of the rule. For example, NumberOfOutgoingTransitionsPerState is defined in metrics/number_of_outgoing_transitions_per_state.py.

  • The class defining the rule shall inherit from ansys.scade.design_rules.utils.Metric (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 metric.

  • The id attribute of the metric 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 metrics and rules, sorted by id: When creating a new metric, 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.Metric to the Python path at the beginning of the file:

      if __name__ == '__main__':
   # metric 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:

      if __name__ == '__main__':
   # metric instantiated outside of a package
   MyMetric()