.map(sourceTree -> sourceTree.matching(filesFilter))
            .reduce(FileTree::plus)
            .orElse(projectLayout.files().getAsFileTree());
    }

    @TaskAction
    public void checkInvalidPermissions() throws IOException {
        if (Os.isFamily(Os.FAMILY_WINDOWS)) {
            throw new StopExecutionException();
        }
        List<String> failures = getFiles().getFiles()
            .stream()