Unit Testing Interview Questions – Set 1

This page lists down the practice tests / interview questions and answers for unit testing (general concepts) which applies for all programming languages. Those wanting to test their unit testing knowledge would find this test useful enough. The goal for this practice test is to help you do quick check of your knowledge in unit testing and prepare appropriately. More importantly, when you are preparing for interviews, these practice tests are intended to be handy enough. Those going for freshers / intern interviews in the area of programming language or for developer positions would also find these practice tests / interview questions to be very helpful.

Following topics have been covered as part of the test on this page:

• Basic fundamentals/concepts around unit testing
• Concepts related with test doubles
• Concepts related with unit testing building blocks such as stub, mock, spy etc

Unit Testing Concepts (Brush up)

The following is quick notes for refreshing your concepts around unit testing:

• Unit testing is testing block of code in isolation
• Unit tests are intended to form the documentation for your code
• It is difficult to write unit tests having high code coverage for code having high cyclomatic complexity
• Unit tests uses test doubles such as stub, spy, mock for mocking external dependencies
• It is important to do code refactoring and bring down code cyclomatic complexity to achieve high code coverage
• It is easier to achieve higher code coverage if the block of code is cohesive enough.

Practice Tests on Unit Testing

Please feel free to share your thoughts on concepts / interview questions / practice tests on unit testing listed on this page.