title: "Object scalatest is not a member of package org" where is the directory?
body: <p>I've seen my people stuck on this problem. And so as I. And many people said using sbt. And currently I've already downloaded sbt. But I don't know where the directories are, such as dir "/src/main/scala" or dir 
  "/src/test/scala", could anybody tell me where are the directories? Thanks</p>