Unit testing is an essential step in software development that helps to ensure good code quality, robustness, maintainability, and more. This page aims at providing a quick summary of the unit testing best practices.
One definition of unit testing would be
Unit Testing is a technique for testing individual units of source code to ensure that they work as desired. In other words, unit testing is used to ensure the smallest possible testable parts of an application are tested to make sure that they work correctly.
https://www.developer.com/java/best-practices-unit-testing-java/
Unit testing, in general, is language-independent, but certain aspects e.g. test organization and naming will differ e.g. between Go, Rust, and Java.
Summary
- F.I.R.S.T (Fast, Independent, Repeatable, Self-Validating, Timely) see [1]
- Give your test cases meaningful names that ensure the reader can quickly understand the goal and expectations of the test. Following the given_when_then schema may be helpful.
- Your test cases should be able to fail (test cases that always pass add no value)
- Keep your test cases simple and “clean” (“Readability, readability, and readability” [Clean Code])
- Automatically run your test cases
- Test one thing (single concept) at a time (avoid multiple assertions in one test case)
- Mock External Dependencies
- Avoid Code Redundancy
- Aim at 80%+ line coverage
- Avoid testing implementation details
Resources
[1] Clean Code: A Handbook of Agile Software Craftsmanship
https://www.baeldung.com/java-unit-testing-best-practices
https://www.developer.com/java/best-practices-unit-testing-java/
https://howtodoinjava.com/best-practices/unit-testing-best-practices-junit-reference-guide/