code: function(file, tasks, options) {
                /** skip if no tasks or checking Gruntfile */
                if (!tasks.length || file && file === 'Gruntfile.js') {
                  return '';
                }
  
                var result = '* ' + file + ' (' + tasks.length + ')\n\n';
  
                /** iterate over tasks, add data */
                tasks.forEach(function(task) {
                  result += '    [' + task.lineNumber + ' - ' +
                    task.priority + '] ' + task.line.trim() + '\n';
  
                  result += '\n';
                });
  
                return result;
              }
docs: flow for each file