A talk on PHPTestFest, an event PHPDublin is gladly taking part in. Here we show how easy it is to write a test for the core of PHP, letting you become a core PHP developer.

1. PHP Test Fest
Become a core PHP Developer

2. Who am I?
Lead Developer and Solutions Architect for
DynamicReservations
Writing PHP web apps professionally for 12 yrs
DDD and EventSourcing fanatic (I will talk for hours)
Recovered Architecture Astronaut
Co-Organiser of PHPDublin
@barryosull
barry@tercet.io
http://dev.to/barryosull
http://barryosullivan.me

3. What is PHPTestFest?
World wide event - Sep to Dec 2017
Write tests for the core of PHP
Meeting Virtually and Physically
PHPDublin is taking part!
Day long event, help devs in Ireland write tests

4. Why am I qualified to give this talk?
Because I am a core contributor to PHP

5. The file I committed

6. “Hey, I could do that!”

7. Writing tests in PHP
So easy, even I could do it

8. Testing in PHP
PHP tests are written as PHPT files
These are just PHP files with extra bits
No C code required!
They’re super easy to read and write
Any PHP developer can do it

9. Walk through an example
--TEST --
Test description
--FILE--
Test contents
--EXPECT--
Expected output
php-src/Zend/tests/nullable_types/string.phpt

10. Types of test
1. Basic 2. Error 3. Bug

11. Running your tests
1. Get your machine setup to run the tests
a. Install docker on your machine
b. Run the following command line
curl -s https://raw.githubusercontent.com/herdphp/docker-phpqa/master/bin/installer.sh | bash
2. Fork the PHP-SRC from github
3. Clone to your local machine
4. Create your test file in the tests directory of the file/function you’re testing
5. Run your tests

12. Debugging failing tests
Running a failing test creates the following file extensions with same name as the test
.out - The actual output that the PHP code from the --FILE-- section generated
.exp - The output we expected from the --EXPECT-- section
.diff - A diff file with the actual output compared to the expected output
.log - Both actual and expected output in one file
.php - The --FILE-- section as a PHP file
.sh - A bash script that runs the PHP file in the same environment that run-tests ran it

13. Example diff file
php-src/Zend/tests/nullable_types/string.phpt php-src/Zend/tests/nullable_types/string.diff

14. Submitting your test
1. Push your changes to your fork on github
2. Create a PR between your branch and master
3. Wait …
4. Celebrate when it’s accepted!

15. Finding untested code
The whole point of writing a test is to test untested code
Go to http://gcov.php.net/
Look for something with low coverage
Write a test for it!

16. The test I wrote
You will not believe how simple it is

17. How I found curl_share_close needed to be
tested

18. How I found curl_share_close needed to be
tested

19. My simple test

20. What it looks like now

21. What it looks like now

22. Tips for navigating the C code
Not as hard as it looks
- PHP_FUNCTION marks the definition of a function
- Look for untested function code
- Goto the php.net definition for that function
- Looks for example code
- Use that as a template for your test

23. Writing a test from scratch
Because a tutorial isn’t complete without a live demo!
(one that will most likely break)

24. We missed an error case
Missed Error Case

25. Live demo time

26. It’s that easy
Today we showed
1. PHPT tests in PHP
2. How to find code to test
3. How to write the tests
4. How to submit tests
5. Wrote a test in ~5 minutes
In other words:

27. PHP Test Fest
Day long event in on a Saturday in September (details TBD).
The Dublin PHPTestFest team
https://groups.google.com/a/phpcommunity.org/group/testfest/ #phptestfest
https://phptestfest.org/
Michael Flanagan
@micflan
Bruno Siqueira
@brunoric
Ken Guest
@kenguest
Barry O Sullivan
@barryosull
Joao Paulo V Martins
@jpvm
Mark Railton
@railto