gulp-less

What is gulp-less?

The gulp-less package is a Gulp plugin that allows you to compile LESS files into CSS. It integrates seamlessly with Gulp's streaming build system, enabling you to automate the process of converting LESS to CSS as part of your build pipeline.

What are gulp-less's main functionalities?

Basic LESS Compilation

This feature allows you to compile LESS files into CSS. The code sample demonstrates a basic Gulp task that reads LESS files from the 'src/less' directory, compiles them into CSS, and writes the output to the 'dist/css' directory.

const gulp = require('gulp');
const less = require('gulp-less');

gulp.task('less', function () {
  return gulp.src('./src/less/**/*.less')
    .pipe(less())
    .pipe(gulp.dest('./dist/css'));
});

Source Maps

This feature allows you to generate source maps for your compiled CSS files. The code sample shows how to initialize source maps before compiling LESS files and then write the source maps to a 'maps' directory.

const gulp = require('gulp');
const less = require('gulp-less');
const sourcemaps = require('gulp-sourcemaps');

gulp.task('less', function () {
  return gulp.src('./src/less/**/*.less')
    .pipe(sourcemaps.init())
    .pipe(less())
    .pipe(sourcemaps.write('./maps'))
    .pipe(gulp.dest('./dist/css'));
});

Error Handling

This feature allows you to handle errors gracefully during the LESS compilation process. The code sample demonstrates the use of the 'gulp-plumber' package to prevent Gulp from crashing on errors.

const gulp = require('gulp');
const less = require('gulp-less');
const plumber = require('gulp-plumber');

gulp.task('less', function () {
  return gulp.src('./src/less/**/*.less')
    .pipe(plumber())
    .pipe(less())
    .pipe(gulp.dest('./dist/css'));
});

Other packages similar to gulp-less

gulp-sass

The gulp-sass package is a Gulp plugin for compiling Sass/SCSS files into CSS. It offers similar functionality to gulp-less but is used for Sass/SCSS instead of LESS. It also supports source maps and error handling.

gulp-stylus

The gulp-stylus package is a Gulp plugin for compiling Stylus files into CSS. Like gulp-less, it integrates with Gulp to automate the build process, but it is designed for Stylus instead of LESS.

gulp-postcss

The gulp-postcss package is a Gulp plugin for transforming CSS with JavaScript plugins. It can be used to process CSS files generated from various preprocessors, including LESS, Sass, and Stylus, offering a more flexible and extensible approach.

README

gulp-less

A LESS plugin for Gulp

Information

Package	gulp-less
Description	Less plugin for gulp
Node Version	>= 0.10
Less Version	>= 2.x
Gulp Version	3.x

Installation

npm install gulp-less

Basic Usage

var less = require('gulp-less');
var path = require('path');

gulp.task('less', function () {
  return gulp.src('./less/**/*.less')
    .pipe(less({
      paths: [ path.join(__dirname, 'less', 'includes') ]
    }))
    .pipe(gulp.dest('./public/css'));
});

Options

The options you can use can be found here. Below is a list of valid options as of the time of writing:

• paths: Array of paths to be used for @import directives
• plugins: Array of less plugins (details)

The filename option is not necessary, it's handled automatically by this plugin. The compress option is not supported -- if you are trying to minify your css, use a css minifier. No sourceMap options are supported -- if you are trying to generate sourcemaps, use gulp-sourcemaps.

Using Plugins

Less now supports plugins, which can add additional functionality. Here's an example of how to use a plugin with gulp-less.

var LessAutoprefix = require('less-plugin-autoprefix');
var autoprefix = new LessAutoprefix({ browsers: ['last 2 versions'] });

return gulp.src('./less/**/*.less')
  .pipe(less({
    plugins: [autoprefix]
  }))
  .pipe(gulp.dest('./public/css'));

More info on LESS plugins can be found at http://lesscss.org/usage/#plugins, including a current list of all available plugins.

Source Maps

gulp-less can be used in tandem with gulp-sourcemaps to generate source maps for your files. You will need to initialize gulp-sourcemaps prior to running the gulp-less compiler and write the source maps after, as such:

var sourcemaps = require('gulp-sourcemaps');

gulp.src('./less/**/*.less')
  .pipe(sourcemaps.init())
  .pipe(less())
  .pipe(sourcemaps.write())
  .pipe(gulp.dest('./public/css'));

By default, gulp-sourcemaps writes the source maps inline in the compiled CSS files. To write them to a separate file, specify a relative file path in the sourcemaps.write() function, as such:

var sourcemaps = require('gulp-sourcemaps');

gulp.src('./less/**/*.less')
  .pipe(sourcemaps.init())
  .pipe(less())
  .pipe(sourcemaps.write('./maps'))
  .pipe(gulp.dest('./public/css'));

Error Handling

By default, a gulp task will fail and all streams will halt when an error happens. To change this behavior check out the error handling documentation here

License

(MIT License)

Copyright (c) 2015 Plus 3 Network [e-mail]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.