gulpfile.js

const spawn = require('child_process').spawn;
const gulp  = require('gulp');
const maps  = require('gulp-sourcemaps');
const babel = require('gulp-babel');
const css   = require('gulp-css');

/* Build */

gulp.task('build-css', function(){
    return gulp.src('src/**/*.css')
        .pipe(css())
        .pipe(gulp.dest('app/'));
});

gulp.task('build-js', () => {
    return gulp.src(['main.js', 'src/**/*.js', '!src/**/*.test.js'])
        .pipe(maps.init())
        .pipe(babel())
        .pipe(maps.write('.'))
        .pipe(gulp.dest('app/'));
});

gulp.task('build', ['build-css', 'build-js']);

/* Copy */

gulp.task('copy-html', () => {
    return gulp.src('src/*.html').pipe(gulp.dest('app/'));
});

gulp.task('copy-assets', () => {
    return gulp.src('assets/**/*').pipe(gulp.dest('app/assets'));
});

gulp.task('copy', ['copy-html', 'copy-assets']);



/* Execute */

const cmd   = (name) => 'node_modules/.bin/' + name;
const args  = (more) => Array.isArray(more) ? ['.'].concat(more) : ['.'];
const exit  = () => process.exit();

gulp.task('start', ['copy', 'build'], () => {
    spawn(cmd('electron'), args(), { stdio: 'inherit' }).on('close', exit);
});


gulp.task('release', ['copy', 'build'], () => {
    spawn(cmd('electron-builder'), args(), { stdio: 'inherit' }).on('close', exit);
});

gulp.task('test', ['copy', 'build'], () => {
    spawn(cmd('jest'), args(), { stdio: 'inherit' }).on('close', exit);
});