How would you convince your company to implement unit tests?

For us, it helped to implement the tools that measure code coverage and give grades, like Code Climate. Somehow it's a bit easier listening to robots.

Code coverage is a flawed measurement, but it can help in a lot of ways

The tragedy of 100% code coverage

Dan Lebrero

#testing

I would say try first to push for functional tests before if it's a web shop.
It always depends on the types of the projects and the allocated budgets.

Try being practical, like, hey guys, remember the time when the 'register' part of the website didn't work because of push X? Here's a way we can easily test for that. Having clear examples is always a good first step.

Who is "them" ?

If it's your developer colleagues you shouldn't have too much trouble convincing them of the benefits, writing tests has more or less been industry standard for around 10 years now.

In short

• Less bugs
• Much safer refactoring so easier to change code
• So faster development in the long run

If it's management, I would contest that you do not work at a super cool company. Do you ask permission to write classes? if statements? In 2018 writing tests is just as much as being a developer as refactoring is.

As a professional you are the expert being paid to make the right decisions as to how to make a maintainable system, not management.

Do they have functional / integration tests or no tests at all? Unit tests might not be worth it in some scenarios, especially if you have to deal with a legacy app with no tests.

I would bring up the rate of bugs and regressions and start from there. In the meantime you can start testing your code and maybe start adding those few tests in the CI pipeline.

It’s a basic truth that (a) adding features and (b) being relatively bug free, are equally essential to most businesses that want to attract and retain customers. Unit tests allow you to focus on the former, while having confidence that you’re doing fine with regard to the latter.

Convincing the company could be one of two things and I’ll just address them both.

Convincing leadership that you need tests of any kind is simple: “we need to do a little bit more work now in order to ensure that when someone new comes along and breaks things, they know immediately, without asking another developer, that something is wrong.”

Convincing other developers is also fairly simple: “we write unit tests so that when we break stuff we can get instant feedback on what we broke. We might even have planned for that to break because we’re changing a contract, then we see it break and have confirmation of that.”

Unit tests might be hard to sell. Even at my current company, we have very little unit tests. But we have lot of tests, mostly functional and integration tests that being automated. Tests that every developer can run with just a single command make tests, or hook up into CI tools that automatically run on open PR or certain commits. This is much easier to sell. Who don't want just sitting around while computer do the work, instead of endless clicking and typing the same thing over and over again.

It amazed us when people say we don't do testing. What? You didn't test your code. So you just wrote it and ship it, and it just work? That's heaven. What they actually mean is that they don't automate their tests. Truth is, everyone are doing tests, the moment they write single line of code. This I think the crucial understanding we must put first. When we talk about writing tests, people think that it totally new things, so it must be hard and probably not worth doing it. But once we make them realized that it's no different than what they already doing (just being more efficient), they will start seeing the value of doing it.

A former agile coach of ours told a story from back in time he was a CTO. Top management didn't want to invest in (unit)testing, they didn't support the idea to say the least.

One evening the CTO told the big boss that he could save him X amount of money very simply. Words went on, this future coach showed the CEO how to implement unit tests and how they help to prevent bugs.

The next days, communication arrived from the top that everyone should write unit tests for the new code.

So try to sell it with what the business like. They like more revenue and less money spent.

Is funny because I'm right in the middle of this exact dilemma. I was handed a large project and part of that is a major refactor of one of our mission critical components. So I am building my integration to work independently and then when it comes to making the full switch I'm going to fully build out all tests. I have a feeling when the transition goes smoothly, without breaking anything, my lead will see the value.

I wonder why people don't implement unit tests?

Our industry made awesome progress when deciding to start writing tests as the standard, but still need to add the DESIGN!
Which for me implies thinking/writing the software as interconnected pieces which play different roles.
At that point, writing isolated tests for those Units should be the norm.