What are unit testing and integration testing, and

Question

I've seen other people mention several types of testing on Stack Overflow.

The ones I can recall are unit testing and integration testing. Especially unit testing is mentioned a lot. What exactly is unit testing? What is integration testing? What other important testing techniques should I be aware of?

Programming is not my profession, but I would like it to be some day;stuff about production etc is welcomed too.

Answer 1

The other important technique is regression testing. In this technique, you maintain a suite of tests (called the regression suite), which are usually run nightly as well as before every checkin. Every time you have a bug fix you add one or more tests to the suite. The purpose is to stop you from re-introducing old bugs that have already been fixed. (The problem is surprisingly common!)

Start accumulating your regression suite early, before your project gets big, or you'll regret it. I surely have!

Answer 2

Unit Testing: The testing done to a unit or to a smallest piece of software. Done to verify if it satisfies its functional specification or its intended design structure.

Integration Testing: Testing the related modules together for its combined functionality.

Regression Testing: Testing the application to verify that modifications have not caused unintended effects.

Smoke Testing: Smoke testing is verified whether the build is testable or not.

Answer 3

Unit testing is simply the idea of writing (hopefully) small blocks of code to test independent parts of your application.

For example, you might have a calculator application and you need to make sure the addition function works. To do this you write a separate application that calls the addition function directly. Then your test function will evaluate the result to see if it jives with what you expected.

It's basically calling your functions with known inputs and verifying the output is exactly what you expected.