AFAICS there is a `/ "main" /` missing in here:

~~~
> show source-directory
[info] genjavadoc-plugin/*:sourceDirectory
[info] 	/Users/rkuhn/comp/scala/genjavadoc/plugin/src
[info] tests/*:sourceDirectory
[info] 	/Users/rkuhn/comp/scala/genjavadoc/tests/src
[info] javaOut/*:sourceDirectory
[info] 	/Users/rkuhn/comp/scala/genjavadoc/javaOut/src
[info] top/*:sourceDirectory
[info] 	/Users/rkuhn/comp/scala/genjavadoc/src
~~~