setAuthor(author);
        return this;
    }

    public StandardJavadocDocletOptions author() {
        return author(true);
    }

    /**
     * -splitindex
     * <p>
     * Splits the index file into multiple files, alphabetically, one file per letter,
     * plus a file for any index entries that start with non-alphabetical characters.
     */
    @Input
    public boolean isSplitIndex() {

        assertDirectorySnapshot(s4, other)
        assertPartialDirectoryNode(s2, parent)
        flatten(s4) == [parent.path, "1:dir1", "2:child1", "1:dir2", "1:dir3", "1:dir4"]
    }

    def "splits and merges prefixes as directories are added"() {
        def parent = tmpDir.createDir()
        def dir1 = parent.createDir("dir1")
        def dir1dir2 = dir1.createDir("dir2")