BDD with PHPSpec

The first time I saw the abbreviation BDD I thought it was a miss-print of TDD (Test Driven Development), but it’s not. It stands for Behaviour Driven Development and it is a technique derived from TDD. The difference between the two is a bit nuanced and best felt when you start using some BDD tools. One such tool is PHPSpec. It will help you write better code and have fun in the process. Sounds good? Let’s give it a try!

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1. Behaviour Driven Development with PHPSpec Zvonimir Spajic
2. Behaviour Driven Development
3. Behaviour Driven Development technique derived from test-first development
4. Behaviour Driven Development focus on behaviour not implementation technique derived from test-first development
5. It's using examples to talk through how an application behaves... And having conversations about those examples. Dan North
7. a tool which can help you write clean and working PHP code using Behaviour Driven Development
8. a tool which can help you write clean and working PHP code using Behaviour Driven Development at the spec level
9. { "require-dev": { "phpspec/phpspec": "^4.0" }, "config": { "bin-dir": "bin" }, "autoload": {"psr-0": {"": "src"}} }
10. requirement:
11. Dog requirement:
14. <?php namespace spec\App; use App\Dog; use PhpSpec\ObjectBehavior; use Prophecy\Argument; class DogSpec extends ObjectBehavior { function it_is_initializable() { $this->shouldHaveType(Dog::class); } }
19. <?php namespace App; class Dog { }
20. behaviour:
21. Dog can make a sound behaviour:
22. <?php # spec/App class DogSpec extends ObjectBehavior { // ... function it_should_make_a_sound() { $this->makeSound()->shouldBe('Vuf Vuf'); } }
31. <?php # src/App class Dog { public function makeSound() { return 'Vuf Vuf'; } }
32. Matchers describe how an object should behave
33. // Identity matchers $this->getRating()->shouldBe(5); $this->getTitle()->shouldBeEqualTo("Star Wars"); $this->getReleaseDate()->shouldReturn(233366400); $this->getDescription()->shouldEqual("Inexplicably popular children's film"); // Comparison Matcher $this->getRating()->shouldBeLike('5'); // Type Matcher $this->shouldHaveType('Movie'); $this->shouldReturnAnInstanceOf('Movie'); $this->shouldBeAnInstanceOf('Movie'); $this->shouldImplement('Movie'); // Count Matcher $this->getDirectors()->shouldHaveCount(1); // IterableContain Matcher¶ $this->getCast()->shouldContain('Jane Smith'); // Throw Matcher $this->shouldThrow('\InvalidArgumentException')->duringSetRating(-3); $this->shouldThrow('\InvalidArgumentException')->during('setRating', array(-3)); $this->shouldThrow('\InvalidArgumentException')->duringInstantiation(); // ...
34. behaviour:
35. Dog can greet a Person behaviour:
36. Stubs describe how we interact with object we query
37. <?php # spec/App class DogSpec extends ObjectBehavior { // ... function it_can_greet_a_person(Person $person) { $person->name()->willReturn('Mike'); $this->greet($person)->shouldBe('Hello Mike, Vuf Vuf'); } }
42. <?php # spec/App class DogSpec extends ObjectBehavior { // ... function it_can_greet_a_person(Named $named) { $named->name()->willReturn('Mike'); $this->greet($person)->shouldBe('Hello Mike, Vuf Vuf'); } }
51. <?php # src/App interface Named { public function name(); }
52. <?php # src/App class Dog { public function makeSound() { return 'Vuf Vuf'; } public function greet($argument1) { // TODO: write logic here } }
53. <?php # src/App class Dog { public function makeSound() { return 'Vuf Vuf'; } public function greet(Named $named) { return 'Hello ' . $named->name() . 'Vuf Vuf'; } }
56. spec:
57. Person has a name spec:
58. <?php # src/App class PersonSpec extends ObjectBehavior { // .. function it_returns_the_name_it_was_constructed_with() { $this->beConstructedWith('Mike'); $this->name()->shouldBe('Mike'); } }
65. <?php # src/App class Person implements Named { public function __construct($argument1) { // TODO: write logic here } public function name() { // TODO: Implement name() method. } }
66. <?php # src/App class Person implements Named { private $name; public function __construct(string $name) { $this->name = $name; } public function name() { return $this->name; } }
69. spec:
70. Person can change it's name spec:
71. <?php # spec/App class PersonSpec extends ObjectBehavior { // ... function it_returns_new_name_if_renamed() { $this->beConstructedWith('Mike'); $this->renameTo ('Mary'); $this->name()->shouldBe('Mary'); } }
76. <?php # src/App class Person implements Named { private $name; public function __construct(string $name) { $this->name = $name; } public function name() { return $this->name; } public function renameTo($argument1) { // TODO: write logic here } }
77. <?php # src/App; class Person implements Named { private $name; public function __construct(string $name) { $this->name = $name; } public function name() { return $this->name; } public function renameTo(string $name) { $this->name = $name; } }
80. <?php # spec/App class PersonSpec extends ObjectBehavior { function it_returns_the_name_it_was_constructed_with() { $this->beConstructedWith('Mike'); $this->name()->shouldBe('Mike'); } function it_returns_new_name_if_renamed() { $this->beConstructedWith('Mike'); $this->renameTo ('Mary'); $this->name()->shouldBe('Mary'); } }
81. <?php # spec/App class PersonSpec extends ObjectBehavior { function let() { $this->beConstructedWith('Mike'); } function it_returns_the_name_it_was_constructed_with() { $this->name()->shouldBe('Mike'); } function it_returns_new_name_if_renamed() { $this->renameTo ('Mary'); $this->name()->shouldBe('Mary'); } }
82. behaviour:
83. When a Dog greets a Person, it should be logged behaviour:
84. Mocks and Spies describe how we interact with object we command
85. <?php # spec/App class DogSpec extends ObjectBehavior { function let(Logger $logger) { $this->beConstructedWith($logger); } // ... function it_logs_the_greeting(Named $named, Logger $logger) { $named->name()->willReturn('Mike'); $logger->log('Hello Mike, Vuf Vuf')->shouldBeCalled(); $this->greet($named); } }
90. <?php # src/App class Dog { public function __construct($argument1) { // TODO: write logic here } public function makeSound() { return 'Vuf Vuf'; } public function greet(Named $named) { $greeting = 'Hello ' . $named->name() . ', Vuf Vuf'; return $greeting; } }
91. <?php # src/App class Dog { private $logger; public function __construct(Logger $logger) { $this->logger = $logger; } public function makeSound() { return 'Vuf Vuf'; } public function greet(Named $named) { $greeting = 'Hello ' . $named->name() . ', Vuf Vuf'; $this->logger->log($greeting); return $greeting; } }
95. Resources Driving quality with PhpSpec by Ciaran McNulty phpspec: Testing... *Designing* with a Bite Introducing BDD
96. Thank You!