Talk given in French at ConFoo 2015 Le TDD (Test Driven Development) gagne en popularité dans la communauté PHP. C’est maintenant une pratique accepté. Mais commencer peut sembler difficile. Dans cette session, nous allons voir ce qu’est le TDD. Nous allons commencer par voir les principes. Puis les outils utilisés, et comment s’en servir au quotidien. Nous allons aussi voir les difficultés souvent rencontrées et comment les contourner.

1. Commencer avec le TDD
Eric Hogue - @ehogue
Confoo - 2014-02-27
1

2. TDD
2

3. Où commencer?
3

4. Tests unitaires
4

5. Tests unitaires
est une procédure permettant de vérifier le bon
fonctionnement d'une partie précise d'un
logiciel ou d'une portion d'un programme
(appelée « unité » ou « module »).
http://fr.wikipedia.org/wiki/Test_unitaire
5

6. Ne pas traverser de frontières
6

7. Outils
● SimpleTest
● atoum
● PHPT
● PHPUnit
7

8. 8

9. Installation - Phar
$ wget
https://phar.phpunit.de/phpunit.phar
$ chmod +x phpunit.phar
$ mv phpunit.phar /usr/local/bin/phpunit
9

10. Installation - Composer
# composer.json
{
"require-dev": {
"phpunit/phpunit": "4.5.*"
}
}
$ composer install
10

11. PHPUnit
FactorialTest.php
<?php
class FactorialTest extends
PHPUnit_Framework_TestCase {
}
11

12. public function testSomething() {
}
/** @test */
public function somethingElse() {
}
12

13. ● Arrange
● Act
● Assert
13

14. Arrange
/** @test */
public function factOf1() {
$factorial = new Factorial;
}
14

15. Act
/** @test */
public function factOf1() {
$factorial = new Factorial;
$result = $factorial->fact(1);
}
15

16. Assert
/** @test */
public function factOf1() {
$factorial = new Factorial;
$result = $factorial->fact(1);
$this->assertSame(1, $result);
}
16

17. PHPUnit Assertions
● $this->assertTrue();
● $this->assertEquals();
● $this->assertSame();
● $this->assertContains();
● $this->assertNull();
● $this->assertRegExp();
● ...
17

18. Preparing For Your Tests
setup() -> Avant chaque test
teardown() -> Après chaque test
setUpBeforeClass() + tearDownAfterClass()
Une fois par test
18

19. 19

20. TDD
20

21. 3 règles du TDD - Uncle Bob
● You are not allowed to write any production
code unless it is to make a failing unit test
pass.
● You are not allowed to write any more of a
unit test than is sufficient to fail;
○ and compilation failures are failures.
● You are not allowed to write any more
production code than is sufficient to pass the
one failing unit test.
http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd
21

22. Red - Green - Refactor
Red
Écrire un test qui échoue
22

23. Red - Green - Refactor
Green
Le faire passer
23

24. Red - Green - Refactor
Refactor
Régler les raccourcis pris
24

25. /** @test */
public function create() {
$this->assertNotNull(new Factorial);
}
25

26. class Factorial {
}
26

27. /** @test */
public function factOf1() {
$facto = new Factorial;
$this->assertSame(1,
$facto->fact(1));
}
27

28. public function fact($number) {
return 1;
}
28

29. Duplication
public function create() {
$this->assertNotNull(new Factorial);
}
public function factOf1() {
$facto = new Factorial;
...
29

30. public function setup() {
$this->facto = new Factorial;
}
/** @test */
public function factOf1() {
$this->assertSame(1,
$this->facto->fact(1));
}
30

31. /** @test */
public function factOf2() {
$this->assertSame(2,
$this->facto->fact(2));
}
31

32. public function fact($number) {
return $number;
}
32

33. Plus de duplication
/** @test */
public function factOf1() {
$this->assertSame(1,
$this->facto->fact(1));
}
/** @test */
public function factOf2() {
$this->assertSame(2,
$this->facto->fact(2));
} 33

34. public function factDataProvider() {
return [
[1, 1],
[2, 2],
];
}
34

35. /**
* @test
* @dataProvider factDataProvider
*/
public function factorial($number,
$expected) {
...
35

36. …
$result =
$this->facto->fact($number);
$this->assertSame($expected,
$result);
}
36

37. public function factDataProvider() {
…
[2, 2],
[3, 6],
...
37

38. public function fact($number) {
if ($number < 2) return 1;
return $number *
$this->fact($number - 1);
}
38

39. Beaucoup
de travail
39

40. 40

41. Dépendances
41

42. Problème
class Foo {
public function __construct() {
$this->bar = new Bar;
}
}
42

43. Injection des dépendances
43

44. Setter Injection
class Foo {
public function setBar(Bar $bar) {
$this->bar = $bar;
}
}
public function doSomething() {
// Use $this->bar
}
44

45. Constructor Injection
class Foo {
public function __construct(
Bar $bar) {
$this->bar = $bar;
}
...
}
45

46. Passer la dépendance aux méthodes
class Foo {
public function doSomething(
Bar $bar) {
// Use $bar
}
}
46

47. Système de fichiers
47

48. vfsStream
Système de fichier virtuel
composer.json
"require-dev": {
"mikey179/vfsStream": "*"
},
48

49. Vérifier la création d’un répertoire
$root = vfsStream::setup('dir');
$parentDir = $root->url('dir');
//Code creating sub folder
$SUT->createDir($parentDir, 'test');
$this->assertTrue(
$root->hasChild('test'));
49

50. Lire un fichier
$struct = [
'subDir' => ['test.txt'
=> 'content']
];
$root = vfsStream::setup('root',
null, $struct);
$parentDir = $root->url('root');
...
50

51. Lire un fichier
…
$content = file_get_contents(
$parentDir . '/subDir/test.txt');
$this->assertSame('content',
$content);
51

52. Base de données
52

53. Mocks
Remplace une dépendance
● PHPUnit mocks
● Mockery
● Phake
53

54. Création
$mock = $this->getMock('NSClass');
$mock = $this->getMockBuilder
('NamespaceClass')
->disableOriginalConstructor()
->getMock();
54

55. $mock->expects($this->once())
->method('methodName')
55

56. $mock->expects($this->once())
->method('methodName')
->with(1, 'aa', $this->anything())
56

57. $mock->expects($this->once())
->method('methodName')
->with(1, 'aa', $this->anything())
->will($this->returnValue(10));
57

58. Mocking PDO
$statement = $this->getMockBuilder
('PDOStatement')
->getMock();
$statement->expects($this->once())
->method('execute')
->will($this->returnValue(true));
...
58

59. ...
$statement->expects($this->once())
->method('fetchAll')
->will(
$this->returnValue(
[['id' => 123]]
)
);
...
59

60. $this->getMockBuilder('PDO')
->getMock();
60

61. …
$pdo = $this->getMockBuilder(
'stdClass')
->setMethods(['prepare'])
->getMock();
$pdo->expects($this->once())
->method('prepare')
->will(
$this->returnValue($statement));
61

62. class PDOMock extends PDO {
public function __construct() {}
}
$pdo = $this->getMockBuilder
('PDOMock')
->getMock();
62

63. mysql_*
63

64. DbUnit
extends
PHPUnit_Extensions_Database_TestCase
public function getConnection() {
$pdo = new PDO('sqlite::memory:');
return $this->
createDefaultDBConnection(
$pdo, ':memory:');
}
64

65. public function getDataSet() {
return $this->
createFlatXMLDataSet('file');
}
65

66. API
66

67. ● Encapsuler
○ ZendHttp
○ Guzzle
○ Classe qui utilise curl
● Mock
○ Retourner le xml/json voulu
67

68. Avantages et inconvénients
68

69. Avantages
69

70. Inconvénients
70

71. “If it doesn't have to
work, I can get it done a
lot faster!”
- Kent Beck
71

72. Inconvénients
72

73. Prochaines étapes?
73

74. Tests en continue - Guard
74

75. Intégration continue
75

76. Commentaires: https://joind.in/13312
twitter: @ehogue
PHP Mentoring: http://phpmentoring.org/
Questions?
76

77. Credits
● Paul - http://www.flickr.com/photos/pauldc/4626637600/in/photostream/
● JaseMan - http://www.flickr.com/photos/bargas/3695903512/
● mt 23 - http://www.flickr.com/photos/32961941@N03/3166085824/
● Adam Melancon - http://www.flickr.com/photos/melancon/348974082/
● Zhent_ - http://www.flickr.com/photos/zhent/574472488/in/faves-96579472@N07/
● Ryan Vettese - http://www.flickr.com/photos/rvettese/383453435/
● shindoverse - http://www.flickr.com/photos/shindotv/3835363999/
● Eliot Phillips - http://www.flickr.com/photos/hackaday/5553713944/
● World Bank Photo Collection - http://www.flickr.com/photos/worldbank/8262750458/
● Steven Depolo - http://www.flickr.com/photos/stevendepolo/3021193208/
● Deborah Austin - http://www.flickr.com/photos/littledebbie11/4687828358/
● tec_estromberg - http://www.flickr.com/photos/92334668@N07/11122773785/
● nyuhuhuu - http://www.flickr.com/photos/nyuhuhuu/4442144329/
● Damián Navas - http://www.flickr.com/photos/wingedwolf/5471047557/
● Improve It - http://www.flickr.com/photos/improveit/1573943815/
● PolliceVersoThumbsUp.jpg - keimevo - https://www.flickr.com/photos/keimevo/14093768567/in/photostream/
● PolliceVersoThumbsDown.jpg - keimevo - https://www.flickr.com/photos/keimevo/14093716370/in/photostream/
● CILights.jpg - Jan Krutisch - https://www.flickr.com/photos/jankrutisch/4272142306/in/photostream/
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