PHP unit testing + new PHPUnit patch for type testing functionality Seems bullet points are not working and some of the slides are not so clear because of Slideshare conversion. Presentation given at phpBenelux meeting August 25, 2010

1. From typing the test to testing the type Wim Godden Cu.be Solutions User meeting Aug 25, 2010

3. PHP developer since 1997 (PHP/FI 2.0)

4. ZCE and ZFCE

5. Developer of OpenX

6. Owner of Cu.be Solutions

7. Currently : PHP Architect @ NMBS

9. OOP experience ?

11. Have you written any ?

13. How does it work ?

14. When and how to test

15. A complete example (with some pitfalls)

16. Some hints & tips along the way

17. Testing the type

19. a complete step-by-step guide

20. a typical unit testing presentation (as you'll notice...)

21. -> Plenty of online resources, tutorials, conference talks, etc. about the regular stuff

24. What's a unit ? <?php class Fridge { protected $beerBottles ; public function getBeerSupply() { return $this ->beerBottles; } public function addBeer( $bottles ) { $this ->beerBottles += $bottles ; return true ; } public function drinkBeer( $bottles ) { $this ->beerBottles -= $bottles ; return true ; } }

26. Add code

27. Add more code

29. Typos (= instead of == in an if-statement)

30. Backwards logic (== instead of !=, < instead of >)

34. -> if a test fails, you know exactly where to look

35. Early detection of bugs

37. repeatable

39. Unit tests -> “this is what's wrong in this piece of code”

40. A simple example <?php class Fridge { protected $beerBottles ; public function addBeer( $bottles ) { $this ->beerBottles += $bottles ; return true ; } public function drinkBeer( $bottles ) { if ( $bottles >= $this ->beerBottles) { $this ->beerBottles -= $bottles ; return true ; } else { // We ran out of beer ! // $wive->sendToStore($beer, 'a lot'); return false ; } } public function getBeerSupply() { return $this ->beerBottles; } } <?php class FridgeTest extends PHPUnit_Framework_TestCase { private $fridge ; public function testAddBeer() { $this ->fridge = new Fridge(); $this ->assertTrue( $this ->fridge->addBeer( 15 )); } public function testDrinkBeer() { $this ->fridge = new Fridge(); $this ->assertTrue( $this ->fridge->drinkBeer( 15 )); } public function testGetBeerSupply() { $this ->fridge = new Fridge(); $this ->assertType( 'integer' , $this ->fridge->getBeerSupply() ); } }

41. How does it work ?

43. Output :

44. ...

45. Time: 0 seconds

46. OK (3 tests, 3 assertions)

48. AssertTrue

49. AssertFalse

50. AssertType

51. AssertGreaterThan

52. AssertNotNull

53. …

54. You can also add your own !

56. Tests should run independent of the result of a previous test

58. tearDown() : destroys the state

60. Fill the fridge with 15 beers

62. Fill the fridge with 15 beers

63. Run the test (see if there's 15 beers in the fridge)

64. -> FAIL !

67. Fill the fridge with 15 beers

71. Fill the fridge with 15 beers

72. Run the test (see if there's 15 beers in the fridge)

75. testAddBeer()

76. tearDown()

77. setUp()

78. teatDrinkBeer()

79. tearDown()

80. setUp()

81. testGetBeerSupply()

82. tearDown() class FridgeTest extends PHPUnit_Framework_TestCase { private $fridge ; protected function setUp() { $this ->fridge = new Fridge(); } protected function tearDown() { $this ->fridge->drinkBeer( $this ->fridge->getBeerSupply() ); } public function testAddBeer() { $this ->assertTrue( $this ->fridge->addBeer( 15 )); } public function testDrinkBeer() { $this ->assertTrue( $this ->fridge->drinkBeer( 15 )); } public function testGetBeerSupply() { $this ->assertType( 'integer' , $this ->fridge->getBeerSupply() ); } }

83. The do's and dont's class User { protected $age ; public function getAge() { return $this ->age; } public function setAge( $newAge ) { if ( $newAge ) { if ( $newAge >= 0 && $newAge <= 150 ) { $this ->age = $newAge ; return true ; } else { return false ; } } else { return false ; } } } class UserTest extends PHPUnit_Framework_TestCase { private $User ; protected function setUp() { $this ->User = new User(); } public function testGetAge() { $this ->assertType( 'integer' , $this ->User->getAge()); } protected static function provideAges() { return array ( array (rand( 0 , 150 )), array (rand( 0 , 150 )), array (rand( 0 , 150 )) ); } /** * @dataProvider provideAges */ public function testSetAge( $age ) { $this ->assertTrue( $this ->User->setAge( $age )); }

85. What about non-integers ?

86. What about empty string ? Null ? protected static function provideInvalidAges() { return array ( array (- 1 ), array ( 151 ), array ( &quot;not an int&quot; ), array ( &quot;&quot; ), array (NULL) ); } /** * @dataProvider provideInvalidAges */ public function testSetAgeInvalid( $age ) { $this ->assertFalse( $this ->User->setAge( $age )); }

87. Good test ? protected static function provideAges() { return array ( array (rand( 0 , 150 )), array (rand( 0 , 150 )), array (rand( 0 , 150 )) ); } /** * @dataProvider provideAges */ public function testSetAge( $age ) { $this ->assertTrue( $this ->User->setAge( $age )); } protected static function provideInvalidAges() { return array ( array (- 1 ), array ( 151 ), array ( &quot;not an int&quot; ), array ( &quot;&quot; ), array (NULL) ); } /** * @dataProvider provideInvalidAges */ public function testSetAgeInvalid( $age ) { $this ->assertFalse( $this ->User->setAge( $age )); }

88. Erratic test results !

89. Bug in the test or the code ? public function setAge( $newAge ) { if ( $newAge ) { if ( $newAge >= 0 && $newAge <= 150 ) { $this ->age = $newAge ; return true ; } else { return false ; } } else { return false ; } } protected static function provideAges() { return array ( array (rand( 0 , 150 )), array (rand( 0 , 150 )), array (rand( 0 , 150 )) ); } /** * @dataProvider provideAges */ public function testSetAge( $age ) { $this ->assertTrue( $this ->User->setAge( $age )); }

90. Bug in the code ! public function setAge( $newAge ) { if (is_int( $newAge )) { if ( $newAge >= 0 && $newAge <= 150 ) { $this ->age = $newAge ; return true ; } else { return false ; } } else { return false ; } } protected static function provideAges() { return array ( array (rand( 0 , 150 )), array (rand( 0 , 150 )), array (rand( 0 , 150 )) ); } /** * @dataProvider provideAges */ public function testSetAge( $age ) { $this ->assertTrue( $this ->User->setAge( $age )); }

91. The code was buggy... what about the test ?

93. always test edge cases

95. invalid parameters

97. -> We're just checking if setAge() returns true or false ! protected static function provideAges() { return array ( array ( 0 ), array (rand( 1 , 149 )), array (rand( 1 , 149 )), array (rand( 1 , 149 )), array ( 150 ) ); }

98. Good tests... public function testSetAgeActuallySets() { $newAge = mt_rand( 0 , 150 ); $this ->User->setAge( $newAge ); $this ->assertEquals( $newAge , $this ->User->getAge() ); } Good tests don't just cover code... they test the functionality of the code !

100. Final methods

101. Long methods

102. Singletons / static methods

103. Deep inheritance

105. How NOT to test try { $billingAddress = new Address(&quot;Meir 12&quot;, 2000, &quot;Antwerpen&quot;, &quot;BE&quot;); $officeAddress = new Address(&quot;Groenplaats 50&quot;, 2000, &quot;Antwerpen&quot;, &quot;BE&quot;); $customer = new Customer(402, &quot;Jan&quot;, &quot;De Man&quot;, 32, $billingAddress, $officeAddress); $product = new Product(92, &quot;Speculaas&quot;, 5.95); $invoice = new Invoice($customer); $invoice.addItemQuantity($product, 5); $lineItems = $invoice.getLineitems(); if ($lineItems.size() == 1) { $actualLineItem = $lineItems.get(0); $this->assertEquals($invoice, $actualLineItem.getInvoice()); $this->assertEquals($product, $actualLineItem.getProduct()); $this->assertEquals($quantity, $actualLineItem, getQuantity()); $this->assertEquals(5.95, $actualLineItem.getUnitPrice()); } else { $this->assertTrue(false, 'Invoice should have exactly one line item'); } deleteObject($invoice); deleteObject($product); deleteObject($customer); deleteObject($billingAddress); deleteObject($officeAddress); } catch (Exception $e) { // Whatever }

106. How NOT to test try { $billingAddress = new Address(&quot;Meir 12&quot;, 2000, &quot;Antwerpen&quot;, &quot;BE&quot;); $officeAddress = new Address(&quot;Groenplaats 50&quot;, 2000, &quot;Antwerpen&quot;, &quot;BE&quot;); $customer = new Customer(402, &quot;Jan&quot;, &quot;De Man&quot;, 32, $billingAddress, $officeAddress); $product = new Product(92, &quot;Speculaas&quot;, 5.95); $invoice = new Invoice($customer); $invoice.addItemQuantity($product, 5); $lineItems = $invoice.getLineitems(); $this->assertEquals(1, $lineItems.size()); $actualLineItem = $lineItems.get(0); $this->assertEquals($invoice, $actualLineItem.getInvoice()); $this->assertEquals($product, $actualLineItem.getProduct()); $this->assertEquals($quantity, $actualLineItem, getQuantity()); $this->assertEquals(5.95, $actualLineItem.getUnitPrice()); deleteObject($invoice); deleteObject($product); deleteObject($customer); deleteObject($billingAddress); deleteObject($officeAddress); } catch (Exception $e) { // Whatever }

107. How NOT to test try { $billingAddress = new Address(&quot;Meir 12&quot;, 2000, &quot;Antwerpen&quot;, &quot;BE&quot;); $officeAddress = new Address(&quot;Groenplaats 50&quot;, 2000, &quot;Antwerpen&quot;, &quot;BE&quot;); $customer = new Customer(402, &quot;Jan&quot;, &quot;De Man&quot;, 32, $billingAddress, $officeAddress); $product = new Product(92, &quot;Speculaas&quot;, 5.95); $invoice = new Invoice($customer); $invoice.addItemQuantity($product, 5); $lineItems = $invoice.getLineitems(); $this->assertEquals(1, $lineItems.size()); $actualLineItem = $lineItems.get(0); $this->assertEquals($invoice, $actualLineItem.getInvoice()); $this->assertEquals($product, $actualLineItem.getProduct()); $this->assertEquals($quantity, $actualLineItem, getQuantity()); $this->assertEquals(5.95, $actualLineItem.getUnitPrice()); try { deleteObject($invoice); } catch (Exception $e) { // Whatever } try { deleteObject($product); } catch (Exception $e) { // Whatever } try { deleteObject($customer); } catch (Exception $e) { // Whatever } try { deleteObject($billingAddress); } catch (Exception $e) { // Whatever } try { deleteObject($officeAddress); } catch (Exception $e) { // Whatever } } catch (Exception $e) { // Whatever }

109. Replace the unneeded data protected $testObjects; public function testInvoice() { $billingAddress = new TestAddress(); $this->addTestObject($billingAddress); $officeAddress = new TestAddress(); $this->addTestObject($officeAddress); $customer = new TestCustomer($billingAddress, $officeAddress); $this->addTestObject($customer); $product = new Product(92, &quot;Speculaas&quot;, 5.95); $this->addTestObject($product); $invoice = new Invoice($customer); $this->addTestObject($invoice); $invoice.addItemQuantity($product, 5); $lineItems = $invoice.getLineitems(); $this->assertEquals(1, $lineItems.size()); $actualLineItem = $lineItems.get(0); $this->assertEquals($invoice, $actualLineItem.getInvoice()); $this->assertEquals($product, $actualLineItem.getProduct()); $this->assertEquals($quantity, $actualLineItem, getQuantity()); $this->assertEquals(5.95, $actualLineItem.getUnitPrice()); } public function tearDown() { $this->deleteTestObjects(); }

111. Until you look at the Invoice class

117. Dependency injection

118. Uses TDD

120. then

122. Write the test first -> code will do what the test dictates

123. It's a habit...

124. and it's addicting !

128. We typed the test... Now let's test the type !

130. Allows type validation during unit testing

131. Time it took to build : a few days

133. See the magic happen

135. When the method is called from our test, it compares the type of each parameter with the type in the docblock :

136. The result : /** * Cat constructor * @param string $name The name of the cat * @param int $lives The number of lives this cat has left */ PHPUnit 3.5 by Sebastian Bergmann. FF... Time: 1 second, Memory: 3.25Mb There were 2 failures: 1) CatTest::test__constructWithNegativeLives Invalid type calling Cat->__construct : parameter 1 ($name) should be of type string but got bool instead in /home/dev/paramtest/tests/CatTest.php 2) CatTest::test__constructWithNegativeLives Invalid type calling Cat->__construct : parameter 2 ($lives) should be of type int but got string instead in /home/dev/paramtest/tests/CatTest.php FAILURES! Tests: 5, Assertions: 8, Failures: 2. $cat = new Cat(true, &quot;9&quot;);

141. (and it forces you to keep the docblock updated,

142. which is good for API documentation quality !)

144. Click on 'Download Source'

145. Run it :

146. > php <path-to-phpunit.php> --check-param-types <your-test.php>

147. Be amazed at how many type issues you have ;-)

149. Slows down unit tests by factor of 2.5

153. Always test the edge cases

155. Test your types for consistency

156. -> Unit tests take a developer from :

157. This code should work

158. to

159. I can prove it works

161. Spinoff of FirstLink Networks (founded in 2000)

162. High-quality open source solutions

163. Centered around PHP

164. Contribute to open source projects

165. (ZF, Xdebug, PHPUnit, OpenX, ...)

166. We're hiring !

167. -> http://cu.be/jobs

168. -> info@cu.be

173. Twitter @wimgtr

174. E-mail [email_address]