val subprojectRoots = platformsFolder.asFile.listFiles(File::isDirectory).plus(subprojectsFolder.asFile).plus(testingFolder.asFile)
        return subprojectRoots.map { it.listFiles(File::isDirectory).asList() }.flatten()
    }

    private
    fun generateSubprojects(): List<GradleSubproject> {
        return generateSubprojectsDirectories()
            .filter {
                File(it, "build.gradle.kts").exists() ||

        val subprojectRoots = File("../platforms").listFiles(File::isDirectory).plus(File("../subprojects"))
        val subProjectFolders = subprojectRoots.map { it.listFiles(File::isDirectory).asList() }.flatten().filter { dir ->
            // filter out the directories that have only a `build` subdirectory - this usually happens after branch switching
            dir.listFiles { _: File, name: String -> name != "build" }!!.isNotEmpty()

            // TODO: This doesn't allow adoc files to be generated?
            task.from(extension.getUserManual().getRoot(), sub -> {
                sub.include("**/*.adoc");
                // Flatten adocs into a single directory
                sub.eachFile(fcd -> fcd.setRelativePath(RelativePath.parse(true, fcd.getName())));
            });

    private static List<Boolean> parametersNullabilityOf(CtBehavior behavior) {
        def annotations = behavior.parameterAnnotations as List<Object[]>
        annotations.collect { Object[] pAnn ->
            pAnn.flatten().any { isNullableCtAnnotation(it) }
        }
    }

    private static boolean hasNullableAnnotation(CtField field) {
        return NULLABLE_ANNOTATIONS.any { field.hasAnnotation(it) }
    }

import org.gradle.api.tasks.SourceTask
import org.gradle.api.tasks.TaskAction

/**
 * Extracts meta-data from the Groovy and Java source files which make up the Gradle API. Persists the meta-data to a file
 * for later use in generating documentation for the DSL, such as by {@link gradlebuild.docs.dsl.docbook.AssembleDslDocTask}.
 */
@CacheableTask
abstract class ExtractDslMetaDataTask extends SourceTask {
    @OutputFile

    }

    def "validates present section links"() {
        given:
        sampleDoc << """
[[prior_section]]
Text

=== Valid Section Links
This section comes earlier: <<prior_section>>
This section comes later: <<subsequent_section>>

[[subsequent_section]]
More text
        """

        when:
        run('checkDeadInternalLinks').build()

        then:
        assertNoDeadLinks()
    }

        mainTestedVersions = testedVersions.map { VersionNumber.parse(it.gradleVersion().version) }
            .groupBy { it.major }
            .map { (_, v) -> listOf(v.minOrNull()!!.format(), v.maxOrNull()!!.format()) }.flatten()
    }

    private
    fun VersionNumber.format() =
        // reformat according to our versioning scheme, since toString() would typically convert 1.0 to 1.0.0

        // TODO: in a typical project, this may need to be the regular javadoc task vs javadocAll

        ObjectFactory objects = project.getObjects();
        // TODO: This breaks if version is changed later
        Object version = project.getVersion();

        TaskProvider<Javadoc> javadocAll = tasks.register("javadocAll", Javadoc.class, task -> {
            task.setGroup("documentation");

        }

        fun assertHasErrors(vararg errors: List<String>) {
            assertHasErrors(*errors.toList().flatten().toTypedArray())
        }

        fun assertHasErrors(vararg errorWithDetail: Pair<String, List<String>>) {

* Be careful when using features introduced in Java 1.7 or later. Some parts of Gradle still need to run on Java 6.
* Normalize file paths in tests. The `org.gradle.util.internal.TextUtil` class has some useful functions for this purpose.