text: var assert = require("assert");
  var path = require("path");
  var Q = require("q");
  var fs = require("graceful-fs");
  var util = require("./util");
  var readdir = Q.denodeify(fs.readdir);
  var lstat = Q.denodeify(fs.lstat);
  
  function processDirP(pattern, dir) {
      return readdir(dir).then(function(files) {
          return Q.all(files.map(function(file) {
              file = path.join(dir, file);
              return lstat(file).then(function(stat) {
                  return stat.isDirectory()
                      ? processDirP(pattern, file)
                      : processFileP(pattern, file);
              });
          })).then(function(results) {
              return util.flatten(results);
          });
      });
  }
  
  function processFileP(pattern, file) {
      return util.readFileP(file).then(function(contents) {
          var result = new RegExp(pattern, 'g').exec(contents);
          return result ? [{
              path: file,
              match: result[0]
          }] : [];
      });
  }
  
  module.exports = function(pattern, sourceDir) {
      assert.strictEqual(typeof pattern, "string");
  
      return processDirP(pattern, sourceDir).then(function(results) {
          var pathToMatch = {};
  
          results.forEach(function(result) {
              pathToMatch[path.relative(
                  sourceDir,
                  result.path
              ).split("\\").join("/")] = result.match;
          });
          
          return pathToMatch;
      });
  };
  