03: All about .phpt files

All about .phpt files :: Writing tests for PHP source

Jul 14, 2017

Now that we know how to run the test suite with run-tests, let's create our first .phpt file.

Create a basic test

We started by creating a basic test file that tested that echo could take a list of arguments. We created a new file in the root php-src directory called echo_basic.phpt.

$ vi echo_basic.phpt
echo - basic test for echo language construct
echo 'This works ', 'and takes args!';
This works and takes args!

Then we ran the basic test with make.

$ make test TESTS=echo_basic.phpt

We talked about the section names a bit.

Testing non-deterministic output

We learned that --EXPECT-- isn't the best section to use when our test generats non-deterministic output. We created an error test for the filemtime() function to illustrate this. We tried to set the --EXPECTF-- section to the following warning.

Warning: filemtime() expects exactly 1 parameter, 0 given in /usr/src/php-src/filemtime_error.phpt on line 5

But we ran into the problem where the line number and file name in the output would change so we used --EXPECTF-- instead so that we could insert substitution characters.

$ vi filemtime_error.phpt

Note: This contrived example is essentially just testing that ZPP works (which is already very well tested) so this isn't a real-world test you'd want to create.

filemtime() - test error case
echo filemtime();
Warning: filemtime() expects exactly 1 parameter, 0 given in %s on line %d

Skipping tests

We discovered that there are situations where tests weren't able to run. This issue came up when we tried to create a test for the curl_init() function but we didn't have the curl extension installed. We implemented the --SKIPIF-- section to alleviate this.

$ vi curl_init_basic.phpt
curl_init() - creates a resource
<?php if(!extension_loaded('curl')) die('skip ext/curl required');  ?>
$ch = curl_init();
$ make test TESTS=curl_init_basic.phpt

Note: Make sure the --SKIPIF-- section outputs the word "skip" if you want the test to skip. Just using exit()/die() won't skip the test alone.

Give yourself some credit

We added a --CREDITS-- section to carve our name into PHP history.

Sammy Kaye Powers me at sammyk dot me
# TestFest Chicago PHP UG 2017-07-14

Some tests have README's

Some of the tests require environment variables and other quirks in order to run. Check out if the tests folder you're in contains a README.

cat ext/pdo_mysql/tests/README


All posts in this series

If you found this guide helpful, say, "Hi" on twitter! I'd love to hear from you. :)