I am trying to make a simple project that just has

build.gradle.kts

and

MyClass.kt

in the project dir.

build.gradle.kts

has

sourceSets { main { java { setSrcDirs(listOf(".")); exclude( "*.kts" ) } } }

. All works from from command line, but Idea doesn't pick up the project dir as a source dir, and doesn't do code completion in

MyClass.kt

.

Please report this issue to http://kotl.in/issue. If you just want a simple project the best way to create it that is guaranteed to work is to just do a "New Project -> Gradle -> Kotlin DSL" in Intellij IDEA.