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RSpec Runner

Crystalball has a custom RSpec runner you can use in your development with bundle exec crystalball command. It builds a prediction and runs it.

Runner Configuration

Config file

Create a YAML file for the runner. Default locations are ./crystalball.yml and ./config/crystalball.yml. Please check an example of a config file and configuration defaults for available options. Please keep in mind that additional generator\prediction strategies can introduce additional configuration options.

Overriding config file

If you want to override the path to config file please set CRYSTALBALL_CONFIG=path/to/crystalball.yml env variable.

Any specific configuration option in crystalball.yml can be overridden by providing ENV variable with "CRYSTALBALL_" prefix. E.g. CRYSTALBALL_EXAMPLES_LIMIT=10 will set examples_limit value to 10 regardless of what you have in config file.

More examples:

  • CRYSTALBALL_EXAMPLES_LIMIT=0 sets no limit on prediction size
  • CRYSTALBALL_MAP_EXPIRATION_PERIOD=0 sets no expiration period for maps
  • CRYSTALBALL_DIFF_FROM=origin/master changes diff building to be git diff origin/master