tasks/lib/process-white-space.js

/*
 * Licensed to the Apache Software Foundation (ASF
 * or more contributor license agreements.  See th
 * distributed with this work for additional infor
 * regarding copyright ownership.  The ASF license
 * to you under the Apache License, Version 2.0 (t
 * "License"); you may not use this file except in
 * with the License.  You may obtain a copy of the
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to 
 * software distributed under the License is distr
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
 * KIND, either express or implied.  See the Licen
 * specific language governing permissions and lim
 * under the License.
 */

var fs = require('fs');
var path = require('path');

// Iterates over a directory
function forEachFile(root, cbFile, cbDone) {
    var count = 0;

    function scan(name) {
        ++count;

        fs.stat(name, function (err, stats) {
            if (err) cbFile(err);

            if (stats.isDirectory()) {
                fs.readdir(name, function (err, files) {
                    if (err) cbFile(err);

                    files.forEach(function (file) {
                        scan(path.join(name, file));
                    });
                    done();
                });
            } else if (stats.isFile()) {
                cbFile(null, name, stats, done);
            } else {
                done();
            }
        });
    }

    function done() {
        --count;
        if (count === 0 && cbDone) cbDone();
    }

    scan(root);
}

module.exports = function processWhiteSpace(processor, callback) {

    var rexp_minified = new RegExp("\\.min\\.js$");
    var rexp_src = new RegExp('\\.js$');
    
    forEachFile('src', function(err, file, stats, cbDone) {
        //if (err) throw err;
        if (rexp_minified.test(file) || !rexp_src.test(file)) {
            cbDone();
        } else {
            var origsrc = src = fs.readFileSync(file, 'utf8');

            // tabs -> four spaces
            if (src.indexOf('\t') >= 0) {
                src = src.split('\t').join('    ');
            }

            // eliminate trailing white space
            src = src.replace(/ +\n/g, '\n');

            if (origsrc !== src) {
                // write it out yo
                processor(file, src);
            }
            cbDone();
        }
    }, callback);
}