Running a single test

[Per Nyfelt]

I am trying to run the single test class groovy.grape.GrapeIvyTest (i.e. 
in the core) from the command line but cannot figure out the syntax

gradlew :test --tests groovy.grape.GrapeIvyTest
...as hinted in the readme results in

* What went wrong:
Execution failed for task ':test'.
> No tests found for given includes: 
[groovy.grape.GrapeIvyTest](--tests filter)

Does anyone know?

Best regards

Per