gulp-lazy-pipelines/gulpFile.js

gulp lazy pipelines for frontend development

const gulp = require('gulp');
const gutil = require('gulp-util');
const buffer = require('gulp-buffer');
const tap = require('gulp-tap');
const babel = require('gulp-babel');
const sourcemaps = require('gulp-sourcemaps');
const concat = require('gulp-concat');
const process = require('process');
const mocha = require('gulp-mocha');

function handleError(err) {
	gutil.log(gutil.colors.red(err.toString()));
	this.emit('end');
}

function getBuildPipeline(src, name, presets, plugins) {
	presets = typeof(presets) === 'string' ? [presets] : presets;
	return gulp.src(src)
		.pipe(sourcemaps.init())
		.pipe(babel({
			presets: presets,
			plugins: plugins
		}))
		.pipe(concat(name))
		.pipe(sourcemaps.write('.'));
}

function getDeployPipeline(src, name, presets, plugins) {
	presets = typeof(presets) === 'string' ? [presets] : presets;
	return gulp.src(src)
		.pipe(babel({
			presets: presets,
			plugins: plugins
		}))
		.pipe(concat(name));
}

// Get global parameters before executing tasks.
const PARAMS = (function (){
	let params = {};

	// Get node major and minor version as a decimal number: major.minor
	params.nodeVersion = Number(process.version.match(/^v(\d+\.\d+)/)[1]);
	gutil.log('Node version'
						,gutil.colors.blue(params.nodeVersion)
						,'is detected');

	if (params.nodeVersion >= 6.0) {
		params.preset = 'es2015-node6';
	}
	else if(params.nodeVersion < 6.0 && params.nodeVersion >= 5.0) {
		params.preset = 'latest-node5';
	}
	// Maybe not work with 0.x versions running on some really old servers
	else if(params.nodeVersion < 5.0) {
		params.preset = 'es2015-node4';
		params.plugins = 'transform-regenerator';
	}
	gutil.log('Using babel preset:'
						,gutil.colors.blue(params.preset)
						,'plugins are'
						, gutil.colors.blue(params.plugins));
	return params;
}());

/*---------- TASKS ----------*/
gulp.task('build', function buildTask() {
	return getBuildPipeline('./src/index.js', 'index.js', PARAMS.preset, PARAMS.plugins)
		.pipe(gulp.dest('./out'));
});

gulp.task('deploy', function deployTask() {
	return getDeployPipeline('./src/index.js', 'index.js', PARAMS.preset, PARAMS.plugins)
		.pipe(gulp.dest('./dist'));
});

gulp.task('build-test', function buildTestTask() {
	return getBuildPipeline('./test/test.js', 'test.js', PARAMS.preset, PARAMS.plugins)
		.pipe(gulp.dest('./out_test'));
});

gulp.task('test', ['build', 'build-test'], function testTask() {
	let src = PARAMS.nodeVersion >= 6 ? 'test/test.js' : 'out_test/test.js';
	return gulp.src(src)
		.pipe(mocha())
		.on('error', handleError);
});

gulp.task('default', ['watch']);

gulp.task('watch', function watchTask() {
	gulp.watch(['src/**/*.js', 'test/**/*.js'], ['test']);
});