private FileCollection inferGroovyClasspath(VersionNumber groovyVersion) {
                // We may already have the required pieces on classpath via localGroovy()
                Set<String> groovyJarNames = groovyJarNamesFor(groovyVersion);
                List<File> groovyClasspath = collectJarsFromClasspath(classpath, groovyJarNames);
                if (groovyClasspath.size() == GROOVY_LIBS.size()) {