Adding a custom filter to gulp-nunjucks-render

gistfile1.txt

var manageEnvironment = function(environment) {
  environment.addFilter('custom', function(str) {
    return 'Olav, du må vakne. Indianarane kjem.';
  });
}

var htmlTask = function() {

  return gulp.src(paths.src)
    .pipe(data(getData))
    .on('error', handleErrors)
    .pipe(render({
      path: [path.join(config.root.src, config.tasks.html.src)],
      envOptions: {
        watch: false
      },
      manageEnv: manageEnvironment
    }))
    .on('error', handleErrors)
    .pipe(gulpif(process.env.NODE_ENV == 'production', htmlmin(config.tasks.html.htmlmin)))
    .pipe(gulp.dest(paths.dest))
    .pipe(browserSync.stream())

}

gulp.task('html', htmlTask)
module.exports = htmlTask