POC commonjs everywhere grunt task

cjsify.js

'use strict';

var DESC = 'Generate bundle from commonjs-everywhere';

var escodegenFormat = {
  indent: {
    style: '  ',
    base: 0
  },
  renumber: true,
  hexadecimal: true,
  quotes: 'auto',
  parentheses: false
};

module.exports = function(grunt) {
  var cjsify = require('commonjs-everywhere').cjsify;
  var escodegen = require('escodegen');
  var path = require('path');

  grunt.registerTask('cjsify', DESC, function() {
    var options = this.options();

    var rawFiles = grunt.config([this.name]),
        files = grunt.task.normalizeMultiTaskFiles(rawFiles);

    function makeAbsolute(filename) {
      if (filename) {
        return path.resolve(filename);
      }
      return filename;
    }

    options.root = makeAbsolute(options.root);

    return files.every(function(f) {
      var src = f.src, dest = f.dest, bundled, out, map, code, filename, sourceMapItem;

      if (src.length !== 1) {
        grunt.log.error('Not exactly one source file: ' + src.join(', '));
        return false;
      }

      src = makeAbsolute(src[0]);

      grunt.log.subhead('Generating ' + dest + ' from ' + src);

      bundled = cjsify(src, options.root, options);
      out = escodegen.generate(bundled, {
        comment: !options.minify,
        sourceMap: true,
        sourceMapWithCode: true,
        sourceMapRoot: options.sourceMap != null ? path.relative(path.dirname(options.sourceMap), root) : '.',
        format: options.minify ? escodegen.FORMAT_MINIFY : escodegenFormat
      });
      map = out.map, code = out.code;

      if ((options.sourceMap || options.inlineSourceMap) && options.inlineSources) {
        for (filename in processed) {
          if (!processed.hasOwnProperty(filename)) continue;
          sourceMapItem = processed[filename];

          map.setSourceContent(sourceMapItem.canonicalName, sourceMapItem.fileContents);
        }
      }

      if (options.sourceMap) {
        grunt.file.write(options.sourceMap, '' + map);

        sourceMappingUrl =
          options.output ?
            path.relative(path.dirname(options.output), options.sourceMap)
          : options.sourceMap;

        if (!options.inlineSourceMap) {
          code = code + "\n//# sourceMappingURL=" + sourceMappingUrl;
        }
      }

      if (options.inlineSourceMap) {
        code = (
          code +
          '\n//# sourceMappingURL=' +
          'data:application/json;charset=utf-8;base64,' + new Buffer('' + map, 'utf-8').toString('base64') + '\n'
        );
      }

      grunt.file.write(dest, code);
      return true;
    });
  });
};