首先我要介绍的是如何安装和测试一个新的shell，以及如何改变默认的shell。

The first thing I need to cover is how to install and test a new shell, and how to change the default shell.

youdao

一开始我要选择两个用例进行测试。

As a starting point, I'll choose two use cases to test.

youdao

这个失败很容易理解，但我不确定是不是真的要“修正”它——我没有测试的这个方法非常微不足道，为这么微不足道的方法添加测试有点浪费精力。

This failure is easy to understand, but I'm not sure I really want to "fix" it — the method I'm not testing is trivial, and adding tests for trivial methods can be a waste of effort.

youdao

A remember about the Periodic Table test which will be added next week on the 23rd.

我要提醒你们,下周23号将会有个周期表测试。

麻省理工公开课 - 固态化学导论课程节选

And I end up going back and doing unit testing anyway, to try and figure out why it doesn't work. So over the years, I've just convinced myself I might as well start where I'm going to end up.

第一次从来不会正常运行,因此无论如何我还要回头去做单元测试,找找哪儿出错了，因此经过这么多年，我已经说服自己既然一定要做单元测试,那么还是一开始就做最好了。

麻省理工公开课 - 计算机科学及编程导论课程节选

But before telling you about this let me sort of Go through some of the hypothesis that we have and That we are now testing about why the subject is Difficult and why these materials assembled what We have assembled them might be useful.

但是谈那之前我要说说,我们之前的一些假设,我们现在正在测试为什么这个学科很难,以及为什么我们整合这些资料是有用的,我们认为把它们整合起来或许有用。

麻省理工公开课 - 媒体、教育、市场课程节选