gulpfile.js

var gulp = require('gulp');
var clean = require('del');
var minifyJS = require('gulp-minify');
var minifyHTML = require('gulp-htmlmin');
var minifyIMG = require('gulp-imagemin');
var cleanCSS = require('gulp-clean-css');
var zip = require('gulp-zip');

gulp.task('cleanDest', function() {
	return clean(['built/**/*']);
});

gulp.task('copyFavicon', function () {
	return gulp.src(['html/favicon.ico'])
		.pipe(gulp.dest('built/'));
});

gulp.task('minifyHTML', function() {
	return gulp.src(['html/*.html'])
		.pipe(minifyHTML({collapseWhitespace: true}))
		.pipe(gulp.dest('built/'));
});

gulp.task('minifyCSS', function(){
	return gulp.src(['css/*.css'])
		.pipe(cleanCSS({compatibility: 'ie8'}))
		.pipe(gulp.dest('built/css'));
});

gulp.task('copyRobots', function() {
	return gulp.src(['html/robots.txt'])
		.pipe(gulp.dest('built/'));
});

gulp.task('zipLogos', function() {
    return gulp.src('built/images/logos/**/*.png')
        .pipe(zip('TROLLPURSE_LOGOS.zip'))
        .pipe(gulp.dest('built/images/logos/'))
});

gulp.task('minifyJS', function() {
	return gulp.src('js/*.js')
		.pipe(minifyJS({
			ext: {
				src:'.js',
				min: '.js'
			}
		}))
		.pipe(gulp.dest('built/js/'));
});

gulp.task('minifyIMG', function() {
	return gulp.src(['images/**/*.*', 'html/*.ico'])
		.pipe(minifyIMG())
		.pipe(gulp.dest('built/images/'));

});

gulp.task('mini-copy', gulp.parallel('minifyHTML', 'minifyJS', 'minifyCSS', 'minifyIMG', 'copyRobots', 'copyFavicon'));

gulp.task('build', gulp.series('cleanDest', 'mini-copy', 'zipLogos', function(done){
	done();
}));