Method <org.gradle.api.tasks.SourceTask.include(groovy.lang.Closure)> has arguments/return type groovy.lang.Closure that is not Gradle public API or primitive or built-in JDK classes or Kotlin classes in (SourceTask.java:0)

    def "validation warnings are reported even when task is skipped"() {
        buildFile << """
            import org.gradle.integtests.fixtures.validation.ValidationProblem

            class InvalidTask extends SourceTask {
                @ValidationProblem File inputFile

                @TaskAction void execute() {
                    println "Executed"
                }
            }

One last thing to note: if you are developing a task that takes collections of source files as inputs, like this example, consider using the built-in link:{groovyDslPath}/org.gradle.api.tasks.SourceTask.html[SourceTask]. It will save you having to implement some of the plumbing that we put into `ProcessTemplates`.

[[sec:link_output_dir_to_input_files]]
=== Linking an `@OutputDirectory` to an `@InputFiles`

 * In previous Gradle versions, the `source` field in `SourceTask` was accessible from subclasses. This is not the case anymore as the `source` field is now declared as `private`.
 * In the Worker API, <<#rel5.0:worker_api, the working directory of a worker can no longer be set>>.