This document discusses unit testing and provides guidance on writing good unit tests. It defines a unit test as code that invokes a unit of work and checks a specific end result. The document notes that integrating AuthService directly in a test is problematic as it makes the test redundant, brittle to code changes, and difficult for others to understand. It then outlines characteristics of good unit tests, including being automated, repeatable, easy to implement, isolated, and able to pinpoint failures. The document demonstrates writing a first unit test in PHPUnit and covers types of assertions, best practices like the AAA pattern and single assertions, and using setup and teardown methods.

1. Unit Test
example by PHPUnit
Eric G
2019

2. What is a unit test ?
A unit test is a piece of code that invokes a unit of
work and checks one specific end result of that unit of
work. If the assumptions on the end result turn out to
be wrong, the unit test has failed. A unit test’s scope
can span as little as a method or as much as multiple
classes.

3. How you test right
now ?
AuthService
.login {
…
}

4. What are problems in
previous case?

5. • It’s considered an integration test
• It’s redundant for many test cases
• Must test every cases after modifying the code in the
same unit
• Other team members don’t know how to test it

6. What makes a good unit test
• It should be automated and repeatable
• It should be easy to implement
• It should be relevant tomorrow
• Anyone should be able to run it at the push of a button
• It should be run quickly
• It should be consistent in its results (it always returns the same result if you don’t change anything
between runs)
• It should have full control of the unit under test
• It should be fully isolated (runs independently of other tests)
• When it fails, it should be easy to detect what was expected and determine how to pinpoint the
problem
Art of unit testing 2nd(1.2 Properties of a good unit test). Roy Osherove

7. Writing the first unit
test

8. Demo
Writing the first test

9. Unit test framework
PHPUnit

10. Why we want to use unites framework
• It can be automated and repeatable
• It can be easy to implement
• It can be relevant tomorrow
• Anyone can be able to run it at the push of a button
• It can be run quickly
• It should be consistent in its results (it always returns the same result if you don’t change anything
between runs)
• It can have full control of the unit under test
• It can be fully isolated (runs independently of other tests)
• When it fails, it should be easy to detect what was expected and determine how to pinpoint the
problem

11. Setting PHPUnit in PHPStorm

16. Demo

17. Types of assertions
• Return value
• State changing
• Object Interaction

18. Important rules in unit test
• AAA(Got When Then) pattern
• Test naming
• Single Assertion

19. Setup & Teardown
Art of unit testing 2nd(Figure 2.5 How NUnit calls SetUp and TearDown). Roy Osherove

20. Demo