grunt 0.4 file.expandMapping and templates

Gruntfile.js

module.exports = function(grunt) {
 
  grunt.initConfig({
    stuff: {
      dest: 'foo/',
      ext: '.bar',
    },
    log_files: {
      my_target: {
        files: grunt.file.expandMapping('**/*.js', '<%= stuff.dest %>', {
          cwd: 'test/fixtures/expand',
          rename: function(destBase, destPath) {
            return destBase + destPath.replace(/\.js$/, '<%= stuff.ext %>');
          }
        })
      }
    }
  });

  console.log('\nThe files object generated with grunt.file.expandMapping:');
  console.log(grunt.config('log_files.my_target.files'));
  console.log('');
 
  grunt.registerMultiTask('log_files', 'Log src/dest pairs in a files object.', function() {
    console.log('%s -> %s', this.file.src, this.file.dest);
  });
 
  grunt.registerTask('update_stuff', 'Update the stuff object', function(dest, ext) {
    grunt.config.set('stuff', {dest: dest + '/', ext: '.' + ext});
  });
};

output.sh

# Given the source files:
# test/fixtures/expand/js/bar.js
# test/fixtures/expand/js/foo.js
 
$ grunt log_files update_stuff:aaa:bbb log_files

The files object generated with grunt.file.expandMapping:
{ '<%= stuff.dest %>js/bar<%= stuff.ext %>': 'test/fixtures/expand/js/bar.js',
  '<%= stuff.dest %>js/foo<%= stuff.ext %>': 'test/fixtures/expand/js/foo.js' }

Running "log_files:my_target" (log_files) task
test/fixtures/expand/js/bar.js -> foo/js/bar.bar
test/fixtures/expand/js/foo.js -> foo/js/foo.bar

Running "update_stuff:aaa:bbb" (update_stuff) task

Running "log_files:my_target" (log_files) task
test/fixtures/expand/js/bar.js -> aaa/js/bar.bbb
test/fixtures/expand/js/foo.js -> aaa/js/foo.bbb

Done, without errors.