Running Spock tests in parallel
I ended up with the following issue on GitHub:
https://github.com/spockframework/spock/issues/691
Comment or whatever if you're also interested in parallel test execution in Spock.
In short, I've found a pull request with enabling parallel execution and it is even merged into one of the branches. However it is not merged into master yet. So the only way out I see for now is to write my own custom BaseSpecRunner
Looks like Spock team added support for parallel execution:
http://spockframework.org/spock/docs/2.0-M4/parallel_execution.html#parallel-execution
requires groovy: >3.0.6