Antlr4 + Kotlin + Intellij errors...

[Nicholas Weaver]

I started with the sample project/discussion from Alexey Yakovlef as a guide and I'm trying to do antlr4 + kotlin.  

Gradle seems to have no problem building the project, however, the IntellIJ Kotlin mode is not recognizing the sourceset for the parser, although it is in the Gradle configuration:

sourceSets {
main {
java {
srcDir(tasks.generateGrammarSource)
}
}
}

Does anyone have suggestions/workarounds for the problem?  Thanks.