Should one test internal implementation, or only test public behaviour?

by

The answer is very simple: you are describing functional testing, which is an important part of software QA. Testing internal implementation is unit-testing, which is another part of software QA with a different goal. That’s why you are feeling that people disagree with your approach.

Functional testing is important to validate that the system or subsystem does what it is supposed to do. Anything the customer sees should be tested this way.

Unit-test is here to check that the 10 lines of code you just wrote does what it is supposed to do. It gives you higher confidence on your code.

Both are complementary. If you work on an existing system, functional testing is the first thing to work on probably. But as soon as you add code, unit-testing it is a good idea also.

More Related Contents:

  1. What is the difference between integration and unit tests?
  2. What Makes a Good Unit Test? [closed]
  3. What’s the difference between unit tests and integration tests? [duplicate]
  4. What is a reasonable code coverage % for unit tests (and why)? [closed]
  5. Does Selenium support headless browser testing?
  6. RSpec vs Cucumber (RSpec stories) [closed]
  7. How to unit test a Go Gin handler function?
  8. How can I unit test a GUI?
  9. Writing “unit testable” code?
  10. Filter JaCoCo coverage reports with Gradle
  11. What is unit testing and how do you do it? [duplicate]
  12. What is unit testing? [closed]
  13. Compare equality between two objects in NUnit
  14. How to test a confirm dialog with Cucumber?
  15. Fill os.Stdin for function that reads from it
  16. Configuring IntelliJ IDEA for unit testing with JUnit
  17. Do MSTest deployment items only work when present in the project test settings file?
  18. Junit5 mock a static method
  19. How to avoid multiple asserts in a JUnit test?
  20. Unit testing with singletons
  21. What is the best way to unit-test SLF4J log messages?
  22. Example invalid utf8 string?
  23. Should it be “Arrange-Assert-Act-Assert”?
  24. Dependency Injection: Turtles all the way down?
  25. Is it possible to mock a function imported from a package?
  26. Rhino Mocks – Difference between GenerateStub & GenerateMock [closed]
  27. Why is it hard to unit test a system that depends on singletons?
  28. Example code for testing the filesystem in Golang
  29. Is duplicated code more tolerable in unit tests?
  30. When is a Test not a Unit-test?

Leave a Comment