mfriedenhagen / spock-stackoverflowerror

Test project for spock StackOverflowError while mocking

See spockframework/spock#1909

• Running mvn -V -q clean test -Dspockframework.version=2.4-M2-groovy-4.0 fails.
• Running mvn -V -q clean test -Dspockframework.version=2.4-M1-groovy-4.0 succeeds.