How does unit testing increase productivity?

Question

I am currently looking for ways to increase the productivity of our team. I read in a number of places that unit testing can be used to improve performance. I can imagine that currently unit tests may be useful in the future, but does this help in the short term? Because I don’t understand how to write more code (= more potential errors) can help us meet deadlines.

Answer 1

Unit testing is not the production of extra lines of code per day.

This means that every day your new lines of code do not cause more errors.

You need to be very careful about what you do when trying to evaluate your “performance”. This can help you meet your deadlines as you spend less time fixing.

This is not something that was aimed at the "short term", as in "we will use unit testing, and our next project will be completed in 80% of cases."

Answer 2

Not a short term, but not a long term, or automatic tests will allow you to detect problems (regressions) caused by improper installation of errors or incorrect development, Faster; and it is definitely nice.

This means that when your application is under testing, every time a bug is fixed, you have less risk for introducing new ones.
And this is also true if the application is still under development: every time a developer commits a new module, you know that it does not violate the rest of the application (or at least interrupt what is covered by automatic tests)

And , the sooner an error is detected, the easier and cheaper it is to fix it : if the error does not have time to affect other developers, this is also better.
What if the developer believes that some “error” (which he does not know is an error) as a function and begins to rely on it? What happens when it begins to be considered an error and is committed? Another code breaks, I suppose: - (

It is also nice that the development of automated tests may mean that more experienced developers know more about the application code: especially if some tests are developed / tested by other developers than those who wrote the code in the first place.
Not sure if this is a “good mark,” but if it is done, it means there will be some kind of code review in place - and it is definitely useful.

And since more experienced developers know the code, more experienced developers will be able to fix bugs in those parts that they did not develop in the beginning.

Answer 3

Unit Test Productivity Improvement

Also read Test Driven Development

Test Development (TDD) is a software development technology that uses short development iterations based on pre-written tests to determine desired improvements or new features. Each iteration code is required to pass this iteration tests. Finally, the programmer or team will reorganize the code to make changes. A key TDD concept is that preparing tests before coding facilitates quick change feedback. Please note that test development is a software development method, not just a testing method.

Answer 4

Despite the gross simplification, the sooner you catch the error, the cheaper it is to fix it. Thus, unit testing will at least lead to some errors.

I suspect that from a performance point of view, it is a question of whether it is easier to fix a bug in the code that brought programmers to mind, as opposed to a bug in code that is “n” months old, etc. However, it is somewhat idealistic to suggest that unit testing (outside the larger testing mode) is a form of silver bullet.

Answer 5

"Test" is the wrong word with unit tests. "Definition of behavior" is perhaps the best term.

Unit tests and TDDs can improve performance (even mid-term) in several ways.

• Code with well-defined behavior is easier to debug since the expected behavior is known.
• Code written using the TDD methodology has clear “seams” that allow you to check individual parts of the code. This makes it easier to narrow down problems when they occur.
• With a strong test suite and well-defined behavior, refactoring is much easier. This allows you to solve design problems with a much lower risk, even if they affect a number of separate classes.
• Because of the above, it is usually easier to determine when something goes wrong, where is the actual place for correction.
• Since TDD-written code generally does not rely on singleton / static behavior or global state, there is less global behavior. With less global behavior, you get fewer side effects.

The biggest advantage, in my experience, of TDD code is the fact that it is clearly defined. You start by defining what the code should do, and then forcing it to do it. This contrasts with “regular” development practices, which often involve writing a bunch of code and then testing it to see what it actually does.

Another advantage of using a TDD-like methodology is that you get working code almost immediately, even if there is no end-to-end solution. And it's almost always easier to add working code to get more working code, rather than writing a bunch of code that is in an unknown state, and then finding out what doesn't work.

Answer 6

How are you going to test without Unit Tests? By clicking, visually checking the answers? Is it possible to write code once and run it repeatedly because of cost or savings?

Are you going to use various error conditions? Can you find errors later if you do not know what the relative costs of fixing errors earlier than later?

However, for me the most important reason is less obvious: if you write tests first (really TDD) or even when you go, you are almost looking at cases of fringe. And the result is that the code is only better. Less recycling.

Another theory, people are very goal oriented. We like rewards and are repeated, which gives us rewards (mmm mmmm reputation ... give me a question to answer :-) seeing these little green ticks as our tests pass motivates us. You can get more code, but it will be written much faster.

Answer 7

I can imagine block tests may be useful in the future, but will this help in the short term?

Yes, because you force your developers and architects to solve one problem at a time.

Because I don’t understand how to write more code (= more potential errors) can help us meet deadlines.

The amount of extra code is exactly the same. n lines of logic = n lines of tests. But, as you know, raw coding is not the part that takes more time, in particular, because you can parallelize it very well. Therefore, writing more code is not a real problem. To meet deadlines, you must create high-quality code to be released, and without testing you have

• there is no way to know if quality is top or not.
• Unable to measure release time. (when all tests pass as the first necessary)

Answer 8

Here are a few thoughts. For my answer, I define performance as the number of lines divided by the number of errors. If applied well, on average, I think unit tests will lead to better performance.

• Stuart Halloway uses an accounting metaphor with two accounts: the test code may seem redundant, but having this other book is a huge win to get a sense of quality.

• In unit tests, the developer (or para-programmer) is the first software client. This is why errors are detected faster, as others have noted. However, the person is also the first client of the OO model, API, etc. If a senior developer is involved (doing the job or as a couple), the quality will improve in terms of design. This has medium to long term benefits. (This is often overlooked.)

• Good unit tests will reveal and execute corner cases. These cases may not be available with vanilla tests, which developers run manually. If you are thinking about bugs found in the field: how many due to some strange state? In my experience, a lot.

It is true that in the wrong hands, unit tests can feel like wheels spinning in the sand. But with some experience, the gain is worth it, even in the short term. Yes, there may be fewer lines of production code, but the error rate will be much better.

Answer 9

When you focus on writing tests after or even before writing real code, you won’t be able to write too large chunks. When you have many small tests, it is very likely that you are structuring your code so that you can write these small tests.

This means that classes do not require a lot of infrastructure to work, etc. Things like dependency injection are also very useful because you might want to introduce layouts for your tests. This leads to more loosely coupled classes that improve the overall quality of the code and make the code more convenient. In addition, the unittests secure network will help you while the software is developing (and not only after the product is ready).

When coding, most (aka all) people make mistakes. This leads to a longer development of small opportunities. If you write tests, the probability of errors decreases, and if you find an error, you can be sure that your error correction will not have any side effects (if your test coverage of the "other" code is good). This saves a lot of time because you do not need to look for code that may be affected by the latest change. This leads to a higher rate of development in the end.

Of course, the developer must practice to write tests, but you will start quite quickly soon. Especially if you get used to libraries that help you write tests like easymock or something like that.

Answer 10

In the short term, I think unit tests are not very helpful, as it only reduces testing time. The smaller the project, the less impact it has.

However, the great thing about unit tests is that when you write them, you can guarantee that a certain type of error that you encoded will always be detected. For a long time they should be, in the medium term, I would recommend them.

And in the short term, they are likely to reduce productivity, but if the project itself is not short-term, you will definitely benefit from them.

Answer 11

If you mean a month or two in the short term, I think the answer is yes. How? When I need to make changes to my own code that I haven’t touched, perhaps in just a few weeks or the code that someone else wrote on the team, I feel much more confident if there are unit tests and the code coverage is good. If there were no tests, I would be more inclined to correct, bypass and not touch the main algorithm at all. Do this a couple of times, and the code will become incomprehensible.

Scenario: project meeting

Product Owner: "We need to do change to X and add the Y function. Is this doable?"

Team: “It would be better to wait for Joe to return. He wrote this code.

A few weeks later.

Joe: "Of course, this can be done, but given all the tests that passed in this module, this is not a quick fix."

Product Owner: "Oh, so ... let this change be postponed for a while ..."

I am not sure if I answer your question. It really depends on how short the short term .; -)

Answer 12

Unit testing improves short-term performance in the following sense: it makes it more likely that your code solves the right problem earlier. The costs of neural cycles for creating tests will make the programmer think about the different use cases and the user interface (or API) of this code.

The opposite scenario will be to encode for a couple of weeks, and only then understand that the code solves half the problem. Now you need to fix your code, or perhaps throw it away and start over.

Answer 13

How does unit testing increase productivity?

The implicit assumption in this matter is that unit testing improves "performance". If we define productivity as the ideal result for a given effort in man-hours, then it can be interpreted as more productive as a production process, achieved less than with given efforts. If the encoder produces "perfect" code, then unit testing will decrease performance.

Testing is not primarily to improve performance, but to test and verify software objects in the sense that you are checking the right product, and the correct building of the right product is built. Creating tests and running them has side effects, the most important of which is that software developers understand the problem they are trying to solve with software.

Answer 14

Modern unit testing is not related to catching errors - it is designing and documenting interfaces. Writing tests helps you understand how your code will be used, as well as documents about how they are intended to be used.

Unit testing can catch errors introduced during refactoring, but this is usually not the main source of errors for a project.

So in conclusion, unit testing will make it easier (i.e. cheaper / faster) to create a better quality code. But this will not help you complete any given task faster.

Read articles about the myths and tricks surrounding unit testing:

• http://blog.stevensanderson.com/2009/08/24/writing-great-unit-tests-best-and-worst-practises/
• http://www.simple-talk.com/dotnet/.net-framework/unit-testing-myths-and-practices/