This document discusses PHPUnit, a unit testing framework for PHP. It covers PHPUnit installation, writing test cases, assertions, fixtures, organizing tests, and best practices for test naming, structure and design including the F.I.R.S.T. principles. Key topics include using PHPUnit to test classes, methods and exceptions, leveraging data providers, fixtures for shared test setup/teardown, and keeping tests clean with single concepts per test.

1. Test in Action – Week 2
Testing Framework
Hubert Chan

2. Testing Framework
• Why using framework?
– Reinventing the wheel?
– Frameworks provides
• Library / API / Syntactic Sugar
• xUnit Pattern
• Stub / Mock
• Log / Test Coverage
• Static Analysis

3. PHPUnit
• PHPUnit
– Unit Testing Framework
– Most common for PHP
– Open Source
– Used in known PHP Frameworks
• Zend Framework
• Kohana
• symfony

4. PHPUnit Installation
• Using pear
– pear channel discover (only once)
pear channel-discover pear.phpunit.de
pear channel-discover components.ez.no
pear channel-discover pear.symfony-project.com
– Install PHPUnit
pear install phpunit/PHPUnit

5. PHPUnit Example
• Test Code
class StackTest extends PHPUnit_Framework_TestCase {
public function testPushAndPop() {
$stack = array();
$this->assertEquals(0, count($stack));
array_push($stack, 'foo');
$this->assertEquals('foo', $stack[count($stack)-1]);
$this->assertEquals(1, count($stack));
$this->assertEquals('foo', array_pop($stack));
$this->assertEquals(0, count($stack));
}
}

6. PHPUnit Test Cases Rule
• General Rule
1. The tests for a class Class go into a class ClassTest.
2. ClassTest inherits (most of the time) from
PHPUnit_Framework_TestCase.
3. The tests are public methods that are named test*.
4. Write Assertions

7. Data Provider
• Data Provider
– Return an iterative object (Iterator interface)
– Use for data-driven testing
• Like ACM Input data
– Use it carefully

8. Data Provider Sample
• Test Code
class DataTest extends PHPUnit_Framework_TestCase {
/**
* @dataProvider provider
*/
public function testAdd($a, $b, $c) {
$this->assertEquals($c, $a + $b);
}
public function provider() {
return array(
array(0, 0, 0),
array(0, 1, 1),
array(1, 0, 1),
array(1, 1, 3)
);
}
}

9. Testing Exception
• Testing Exception
– Testing for failure cases
– Error Handling
– Examine
• Exception Type
• Exception Message
• Exception Code

10. Testing Exception Sample
• Test Code
class ExceptionTest extends PHPUnit_Framework_TestCase {
/**
* @expectedException InvalidArgumentException
* @expectedExceptionMessage Right Message
*/
public function testExceptionHasRightMessage() {
throw new InvalidArgumentException('Some Message', 10);
}
/**
* @expectedException InvalidArgumentException
* @expectedExceptionCode 20
*/
public function testExceptionHasRightCode() {
throw new InvalidArgumentException('Some Message', 10);
}
}

11. Testing Exception Sample
• Test Code
class ExceptionTest extends PHPUnit_Framework_TestCase {
public function testExceptionHasRightMessage() {
$this->setExpectedException(
'InvalidArgumentException', 'Right Message'
);
throw new InvalidArgumentException('Some Message', 10);
}
public function testExceptionHasRightCode() {
$this->setExpectedException(
'InvalidArgumentException', 'Right Message', 20
);
throw new InvalidArgumentException(
'The Right Message', 10
);
}
}

12. Assertion
• Assertions
– assertEquals
– assertTrue / assertFalse
– assertContains
– and etc.

13. Assertion Guideline
• Assertion Guideline
– Using best suitable assertion
– Some assertions are more easy to use
• assertXmlFileEqualsXmlFile()
• assertRegExp()
• and etc.
– Make assertion contains useful message

14. Assertion Compare - Equals
• Test Code
class EqualTest extends PHPUnit_Framework_TestCase {
public function test_AssertTrue() {
$this->assertTrue("123" === "456");
}
public function test_AssertEquals() {
$this->assertEquals("123", "456");
}
}

15. Assertion Compare – Equals (cont.)
• Output
1) EqualTest::test_AssertTrue
Failed asserting that <boolean:false> is true.
/usr/home/hubert/tmp/php/equal_compare.php:6
2) EqualTest::test_AssertEquals
Failed asserting that two strings are equal.
--- Expected
+++ Actual
@@ @@
-123
+456
/usr/home/hubert/tmp/php/equal_compare.php:10

16. Assertion Message
• Prototype
assertEmpty(mixed $actual[, string $message = ''])
• Test Code
class EqualTest extends PHPUnit_Framework_TestCase {
public function test_AssertMessage() {
$handler = new LogViewHandler();
$this->assertNotEmpty(
$handler->generate_ajax(),
"generate_ajax() should not be empty!!"
);
}
}

17. Assertion Message - Output
• Output
1) EqualTest::test_AssertMessage
generate_ajax() should not be empty!!
Failed asserting that a string is not empty.
/usr/home/hubert/tmp/php/equal_compare.php:24

18. xUnit Architecture
• Test Case
• Test fixtures
– Pre-action / Post-action needed to run a test
• Test Suites
– A set of tests that all share the same fixture
– The order of the tests shouldn't matter

19. Test Fixtures
• Fixtures
– Avoid duplicate Arrangement code
– Make test cases focus on Action and Assertion
• Test Fixtures
– setUp()
• Pre-action before each test case
– tearDown()
• Post-action after each test case

20. Test Execution

21. Fixture Example
• Test Code
class StackTest extends PHPUnit_Framework_TestCase {
protected $stack;
protected function setUp() {
$this->stack = array();
}
public function testEmpty() {
$this->assertTrue(empty($this->stack));
}
public function testPush() {
array_push($this->stack, 'foo');
$this->assertEquals('foo', $this->stack[count($this->stack)-1]);
$this->assertFalse(empty($this->stack));
}
public function testPop() {
array_push($this->stack, 'foo');
$this->assertEquals('foo', array_pop($this->stack));
$this->assertTrue(empty($this->stack));
}
}

22. Fixture Guideline
• Fixture Guideline
– Only use setUp and tearDown to initialize or
destroy objects that are shared throughout the
test class in all the tests
• Otherwise, readers don’t know which tests use the
logic inside the setup method and which don’t

23. Sharing Fixture
• Sharing Fixture
– Really few reason to share fixtures
– Good example
• Reuse database connection
– Sample Test Code
class DatabaseTest extends PHPUnit_Framework_TestCase {
protected static $dbh;
public static function setUpBeforeClass() {
self::$dbh = new PDO('sqlite::memory:');
}
public static function tearDownAfterClass() {
self::$dbh = NULL;
}
}

24. Organize PHPUnit Tests
• Mapping for production code and test
middleware_rev tests
|── handlers |── _log
│ └── _details |── bootstrap.php
│ |── TRConverter.class.php |── handlers
│ └── tmql │ └── _details
│ └── │ |── TRConverterTest.php
TMQLEscape.class.php │ └── tmql
└── lib │ └──
TMQLEscapeTest.php
|── lib
└── phpunit.xml

25. Execute PHPUnit tests
• Execute all tests
% phpunit
• Execute all tests in a subdirectory
% phpunit handlers
• Execute single test in a subdirectory
% phpunit --filter TMQLEscapeTest handlers

26. Test Naming
• Test Class Name
– For class name “Util”
– Test class name should be “UtilTest”
– Test filename should be “UtilTest.php”

27. Test Naming
• Function Name
– Test function name should be
test_<function>_<scenario>_<expect_behavior>
– Example
• test_escape_evenBackSlashesData_successEscape

28. Single Assertion / Concept per Test
• Single Assertion / Concept per Test
– If a test failed, the cause may be more obvious
– Compare
• PHPUnit Example
• Fixture Example
– testPushPop test 3 concepts
• Test for Empty / Push / Pop

29. Clean Test
• Clean Test
– Keeping Tests Clean
– Or you will not maintain them
– Test codes are as important code as production
– Write Test API / Utility / DSL
– Clean TDD cheat sheet
• http://www.planetgeek.ch/2011/01/04/clean-code-
and-clean-tdd-cheat-sheets/

30. F.I.R.S.T
• F.I.R.S.T
– Fast
– Independent (isolated)
– Repeatable
– Self-Validating
– Timely

31. References
• Clean Code
• The Art of Unit Testing