grunt-purgecss/tasks/purgecss.js

Grunt plugin for PurgeCSS

'use strict';

var purgecss = require('purgecss');

function getAvailableFiles(grunt, files = []) {
    return files.filter((filepath) => {
        // Warn on and remove invalid source files (if nonull was set).
        if (!grunt.file.exists(filepath)) {
            grunt.log.warn(`Source file "${filepath}" not found.`);
            return false;
        }
        return true;
    });
}
function gruntPurgeCSS(grunt) {
    grunt.registerMultiTask("purgecss", "Grunt plugin for PurgeCSS", function () {
        const done = this.async();
        const options = this.options(purgecss.defaultOptions);
        const promisedPurgedFiles = [];
        for (const file of this.files) {
            const source = getAvailableFiles(grunt, file.src);
            const purgedCss = new purgecss.PurgeCSS()
                .purge({
                ...options,
                css: source,
            })
                .then((purgeCSSResults) => {
                if (typeof file.dest === "undefined") {
                    throw new Error(`Destination file not found`);
                }
                grunt.file.write(file.dest, purgeCSSResults[0].css);
                // Print a success message
                grunt.log.writeln(`File "${file.dest}" created.`);
            });
            promisedPurgedFiles.push(purgedCss);
        }
        Promise.all(promisedPurgedFiles)
            .then(() => {
            done();
        })
            .catch(() => done(false));
    });
}

module.exports = gruntPurgeCSS;