this.groovyCompileOptions = groovyCompileOptions;
    }

    @Override
    public List<File> getGroovyClasspath() {
        return groovyClasspath;
    }

    @Override
    public void setGroovyClasspath(List<File> groovyClasspath) {
        this.groovyClasspath = groovyClasspath;
    }

    @Override
    public boolean incrementalCompilationEnabled() {

import java.util.List;

public interface GroovyCompileSpec extends JvmLanguageCompileSpec {
    MinimalGroovyCompileOptions getGroovyCompileOptions();

    List<File> getGroovyClasspath();

    void setGroovyClasspath(List<File> classpath);

    boolean incrementalCompilationEnabled();

        groovydoc.setLinks(newLinkSet)

        expect:
        groovydoc.getLinks() == newLinkSet
    }

    def "groovy classpath must not be empty"() {
        when:
        groovydoc.setGroovyClasspath(TestFiles.empty())
        groovydoc.generate()

        then:
        thrown(InvalidUserDataException)
    }