你想说服谁?工程师还是经理?如果你试图说服你的工程师同事，我认为你最好的办法是迎合他们的愿望，让他们做出高质量的软件。有许多研究表明，它能发现漏洞，如果他们关心做好工作，这对他们来说就足够了。

如果您试图说服管理层，您将很可能不得不做一些成本/收益推理，说明未检测到的缺陷的成本大于编写测试的成本。一定要把不可转化的成本也包括在内，比如失去客户的信心等等。

单元测试绝对是值得付出努力的。不幸的是，您选择了一个困难的(但不幸的是常见的)场景来实现它。

从单元测试中获得的最大好处是从头开始使用它——在一些精选的小项目中，我有幸在实现类之前编写单元测试(此时接口已经完成)。通过适当的单元测试，您可以在类还处于婴儿期时就发现并修复它们，而不是在将来毫无疑问会集成到复杂系统中的任何地方。

如果您的软件是完全面向对象的，那么您应该能够在类级别上添加单元测试，而不需要太多的努力。如果您没有那么幸运，您仍然应该尽可能地尝试合并单元测试。确保当你添加新功能时，新部分都有清晰的接口，你会发现单元测试让你的工作变得更容易。

One of the best things about unit testing is that your code will become easier to test as you do it. Preexisting code created without tests is always a challenge because since they weren't meant to be unit-tested, it's not rare to have a high level of coupling between classes, hard-to-configure objects inside your class - like an e-mail sending service reference - and so on. But don't let this bring you down! You'll see that your overall code design will become better as you start to write unit-tests, and the more you test, the more confident you'll become on making even more changes to it without fear of breaking you application or introducing bugs.

There are several reasons to unit-test your code, but as time progresses, you'll find out that the time you save on testing is one of the best reasons to do it. In a system I've just delivered, I insisted on doing automated unit-testing in spite of the claims that I'd spend way more time doing the tests than I would by testing the system manually. With all my unit tests done, I run more than 400 test cases in less than 10 minutes, and every time I had to do a small change in the code, all it took me to be sure the code was still working without bugs was ten minutes. Can you imagine the time one would spend to run those 400+ test cases by hand?

当涉及到自动化测试——无论是单元测试还是验收测试——每个人都认为编写可以手动完成的代码是浪费精力，有时这是真的——如果你计划只运行一次测试的话。自动化测试最好的部分是，您可以毫不费力地运行它们几次，并且在第二次或第三次运行之后，您所浪费的时间和精力已经得到了补偿。

最后一个建议是，不仅要对代码进行单元测试，还要先进行测试(详见TDD和BDD)。

偶尔，我自己或我的同事会花几个小时来研究一个不太明显的错误，一旦发现了错误的原因，90%的情况下代码都没有经过单元测试。单元测试并不存在，因为开发人员为了节省时间而偷工减料，但随后却失去了这一点和更多的调试。

花少量的时间来编写单元测试可以节省未来调试的时间。

我同意与大多数人相反的观点: 不编写单元测试是可以的 特别是重原型的编程(例如AI)很难与单元测试相结合。

Unit Testing is one of the most adopted methodologies for high quality code. Its contribution to a more stable, independent and documented code is well proven . Unit test code is considered and handled as an a integral part of your repository, and as such requires development and maintenance. However, developers often encounter a situation where the resources invested in unit tests where not as fruitful as one would expect. In an ideal world every method we code will have a series of tests covering it’s code and validating it’s correctness. However, usually due to time limitations we either skip some tests or write poor quality ones. In such reality, while keeping in mind the amount of resources invested in unit testing development and maintenance, one must ask himself, given the available time, which code deserve testing the most? And from the existing tests, which tests are actually worth keeping and maintaining? See here