really_simple_gulpfile_v4.js

'use strict';

/**
 * Using gulp 4 syntax
 * https://demisx.github.io/gulp4/2015/01/15/install-gulp4.html
 * npm install gulpjs/gulp.git#4.0 --save-dev
 *
 * Note: probably also make a .gitignore for the node_modules folder
 */

const del = require('del');
const gulp = require('gulp');
const prefix = require('gulp-autoprefixer');

gulp.task('build', gulp.series(
  clean,
  gulp.parallel(
    css,
    js
  ),
  watch
));

gulp.task('default', gulp.series('build'));

function clean() {
  return del(['static']);
}

function css() {
  return gulp.src('src/css/*')
    .pipe(prefix({
      browsers: ['last 1 version']
    }))
    .pipe(gulp.dest('static/css'));
}

function js() {
  return gulp.src('src/js/*')
    .pipe(gulp.dest('static/js'));
}

function watch() {
  gulp.watch('src/css', css);
  gulp.watch('src/js', js);
}