Dave Hulbert @dave1010 PHP South Coast #phpsc16

1. Practical intro to
Dave Hulbert
@dave1010

2. I like PhpSpec best because
● Talk to it like a human
● Encourages better code
● Can still use PHPUnit
○ Unit testing existing code
○ Functional / UI / integration tests
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 2

3. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 3

4. Contents
1. TDD in 72 seconds
2. Get up and running with PhpSpec
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 4

5. TDD
in 72 seconds
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 5

6. We write code that isn't needed
Writing wasteful code leads to:
● Bugs
● Lower productivity
● Difficulty in adding new features
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 6

7. TDD solves this
● TDD stands for "Tspecification Driven
Design"
● Work out what code would be useful,
before writing it
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 7

8. How we do TDD
Example of how your code will work
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 8
Red

9. How we do TDD
Minimum code to make it work
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 9
Red Green

10. How we do TDD
Make code simpler and clearer,
without changing behaviour
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 10
Red Green Refactor

11. How we do TDD
Start again
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 11
Red Green Refactor

12. PhpSpec
setup
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 12

13. Setup (1 of 2)
$ mkdir demo
$ cd demo
$ mkdir src
$ composer require --dev phpspec/phpspec
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 13

14. Setup (2 of 2)
$ vim composer.json
...
"autoload": {
"psr-0": {"": "src"}
}
...
$ composer update --lock
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 14

15. Using
PhpSpec
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 15

16. How we do TDD
Example of how your code will work
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 16
Red

17. Describe an object
$ vendor/bin/phpspec
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 17

18. Describe an object
$ vendor/bin/phpspec describe VendingMachine
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 18

19. Describe an object
$ vendor/bin/phpspec describe VendingMachine
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 19

20. Describe an object
$ vendor/bin/phpspec describe VendingMachine
Specification for VendingMachine created in
/home/dave/demo/spec/VendingMachineSpec.php.
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 20

21. Spec is generated automatically
$ tree
├── composer.json
├── composer.lock
├── spec
│ └── VendingMachineSpec.php
├── src
└── vendor
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 21

22. Spec is generated automatically
$ cat spec/VendingMachineSpec.php
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 22

23. Spec is generated automatically
$ cat spec/VendingMachineSpec.php
<?php
class VendingMachineSpec extends ObjectBehavior
{
function it_is_initializable()
{
$this->shouldHaveType('VendingMachine');
}
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 23

24. Run the specification
$ vendor/bin/phpspec run
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 24

25. Run the specification
$ vendor/bin/phpspec run
...
class VendingMachine does not exist.
1 specs
1 example (1 broken)
Do you want me to create `VendingMachine` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 25

26. Run the specification
$ vendor/bin/phpspec run
...
class VendingMachine does not exist.
1 specs
1 example (1 broken)
Do you want me to create `VendingMachine` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 26

27. Get PhpSpec to fix stuff for you
...
Do you want me to create `VendingMachine` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 27

28. Get PhpSpec to fix stuff for you
...
Do you want me to create `VendingMachine` for you?
[Y/n]
y
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 28

29. Get PhpSpec to fix stuff for you
Do you want me to create `VendingMachine` for you?
[Y/n]
y
Class VendingMachine created in
/home/dave/demo/src/VendingMachine.php.
1 specs
1 example (1 passed)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 29

30. Get PhpSpec to fix stuff for you
Do you want me to create `VendingMachine` for you?
[Y/n]
y
Class VendingMachine created in
/home/dave/demo/src/VendingMachine.php.
1 specs
1 example (1 passed)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 30

31. PhpSpec generates code
$ tree
├── composer.json
├── composer.lock
├── spec
│ └── VendingMachineSpec.php
├── src
│ └── VendingMachine.php
└── vendor
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 31

32. PhpSpec generates code
$ cat src/VendingMachine.php
<?php
class VendingMachine
{
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 32

33. How we do TDD
Minimum code to make it work
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 33
Red Green

34. How we do TDD
Make code simpler and clearer,
without changing behaviour
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 34
Red Green Refactor

35. How we do TDD
Start again
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 35
Red Green Refactor

36. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 36

37. How we do TDD
Example of how your code will work
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 37
Red

38. Example of how your code will work
Example: it makes funds available
When I call
$this->insertCoin(20);
then
$this->availableFunds() should be 20
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 38

39. Example of how your code will work
Example: it makes funds available
When I call
$this->insertCoin(20);
then
$this->availableFunds() should be 20
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 39

40. Example of how your code will work
Example: it makes funds available
When I call
$this->insertCoin(20);
then
$this->availableFunds() should be 20
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 40

41. Example of how your code will work
Example: it makes funds available
When I call
$this->insertCoin(20);
then
$this->availableFunds() should be 20
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 41

42. Example of how your code will work
function it_makes_funds_available()
When I call
$this->insertCoin(20);
then
$this->availableFunds() should be 20
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 42

43. Example of how your code will work
function it_makes_funds_available()
When I call
$this->insertCoin(20);
then
$this->availableFunds() should be 20
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 43

44. Example of how your code will work
function it_makes_funds_available()
{
$this->insertCoin(20);
$this->availableFunds() should be 20
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 44

45. Example of how your code will work
function it_makes_funds_available()
{
$this->insertCoin(20);
$this->availableFunds() should be 20
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 45

46. Example of how your code will work
function it_makes_funds_available()
{
$this->insertCoin(20);
$this->availableFunds()->shouldBe(20);
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 46

47. Example of how your code will work
function it_makes_funds_available()
{
$this->insertCoin(20);
$this->availableFunds()->shouldBe(20);
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 47

48. Example of how your code will work
class VendingmachineSpec extends ObjectBehavior
{
...
function it_makes_funds_available()
{
$this->insertCoin(20);
$this->availableFunds()->shouldBe(20);
}
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 48

49. PhpSpec generates code
$ tree
├── composer.json
├── composer.lock
├── spec
│ └── VendingmachineSpec.php
├── src
│ └── VendingMachine.php
└── vendor
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 49

50. Run the specification
$ vendor/bin/phpspec run
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 50

51. Run the specification
$ vendor/bin/phpspec run
Method VendingMachine::insertCoin not found.
Do you want me to create `VendingMachine::insertCoin()
` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 51

52. Run the specification
$ vendor/bin/phpspec run
Method VendingMachine::insertCoin not found.
Do you want me to create `VendingMachine::insertCoin()
` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 52

53. Get PhpSpec to fix stuff for you
n
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 53

54. Get PhpSpec to fix stuff for you
y
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 54

55. Get PhpSpec to fix stuff for you
y
Method VendingMachine::insertCoin() has been created.
Method VendingMachine::availableFunds not found.
Do you want me to create `VendingMachine::
availableFunds()` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 55

56. Get PhpSpec to fix stuff for you
y
Method VendingMachine::insertCoin() has been created.
Method VendingMachine::availableFunds not found.
Do you want me to create `VendingMachine::
availableFunds()` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 56

57. Get PhpSpec to fix stuff for you
y
Method VendingMachine::insertCoin() has been created.
Method VendingMachine::availableFunds not found.
Do you want me to create `VendingMachine::
availableFunds()` for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 57

58. Get PhpSpec to fix stuff for you
y
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 58

59. Get PhpSpec to fix stuff for you
y
Method VendingMachine::availableFunds() has been
created.
expected [integer:20], but got null.
1 specs
2 examples (1 passed, 1 failed)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 59

60. Get PhpSpec to fix stuff for you
y
Method VendingMachine::availableFunds() has been
created.
expected [integer:20], but got null.
1 specs
2 examples (1 passed, 1 failed)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 60

61. Get PhpSpec to fix stuff for you
y
Method VendingMachine::availableFunds() has been
created.
expected [integer:20], but got null.
1 specs
2 examples (1 passed, 1 failed)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 61

62. How we do TDD
Minimum code to make it work
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 62
Red Green

63. Automatically fake return values
$ vendor/bin/phpspec run --fake
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 63

64. Automatically fake return values
$ vendor/bin/phpspec run --fake
Do you want me to make `VendingMachine::
availableFunds()` always return 20 for you?
[Y/n]
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 64

65. Automatically fake return values
y
Method VendingMachine::availableFunds() has been
modified.
1 specs
2 examples (2 passed)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 65

66. PhpSpec generates code
$ cat src/VendingMachine.php
<?php
class VendingMachine
{
public function insertCoin($argument1)
{
// TODO: write logic here
}
public function availableFunds()
{
return 20;
}
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 66

67. public function insertCoin($argument1)
{
// TODO: write logic here
}
public function availableFunds()
{
return 20;
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 67

68. How we do TDD
Make code simpler and clearer,
without changing behaviour
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 68
Red Green Refactor

69. public function insertCoin($argument1)
{
// TODO: write logic here
}
public function availableFunds()
{
return 20;
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 69

70. public function insertCoins(int $coin)
{
// TODO: write logic here
}
public function availableFunds() : int
{
return 20;
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 70

71. How we do TDD
Start again
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 71
Red Green Refactor

72. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 72

73. How we do TDD
Example of how your code will work
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 73
Red

74. Use examples to describe behaviour
function it_accumulates_funds()
{
$this->insertCoin(20);
$this->insertCoin(50);
$this->availableFunds()->shouldBe(70);
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 74

75. Run the specification
$ vendor/bin/phpspec run
...
expected [integer:70], but got 20.
1 specs
3 examples (2 passed, 1 failed)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 75

76. public function insertCoin(int $coin)
{
// TODO: write logic here
}
public function availableFunds() : int
{
return 20;
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 76

77. private $funds = 0;
public function insertCoin(int $coin)
{
$this->funds = $this->funds + $coin;
}
public function availableFunds() : int
{
return $this->funds;
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 77

78. How we do TDD
Make code simpler and clearer,
without changing behaviour
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 78
Red Green Refactor

79. How we do TDD
Start again
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 79
Red Green Refactor

80. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 80

81. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 81
function it_uses_funds_when_buying(Catalog $catalog)
{
$catalog->howMuchIsA('kitten')->willReturn(30);
$this->insertCoin(50);
$this->buy('kitten');
$this->availableFunds()->shouldBe(20);
}
Use examples to describe behaviour

82. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 82
function it_uses_funds_when_buying(Catalog $catalog)
{
$catalog->howMuchIsA('kitten')->willReturn(30);
$this->insertCoin(50);
$this->buy('kitten');
$this->availableFunds()->shouldBe(20);
}
Use examples to describe behaviour

83. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 83
function it_uses_funds_when_buying(Catalog $catalog)
{
$catalog->howMuchIsA('kitten')->willReturn(30);
$this->insertCoin(50);
$this->buy('kitten');
$this->availableFunds()->shouldBe(20);
}
Use examples to describe behaviour

84. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 84
function let(Catalog $catalog)
{
$this->beConstructedWith($catalog);
}
Let $this be constructed with

85. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 85
$ vendor/bin/phpspec run
Would you like me to generate an interface `Catalog`
for you? [Y/n]
interface Catalog
{
}
PhpSpec generates interfaces

86. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 86
$ vendor/bin/phpspec run
Would you like me to generate a method signature
`Catalog::howMuchIsA()` for you? [Y/n]
interface Catalog
{
public function howMuchIsA($argument1);
}
PhpSpec generates interfaces

87. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 87
$ vendor/bin/phpspec run
Do you want me to create `VendingMachine::
__construct()` for you? [Y/n]
public function __construct($argument1)
{
// TODO: write logic here
}
PhpSpec generates code

88. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 88
private $catalog;
public function __construct(Catalog $catalog)
{
$this->catalog = $catalog;
}
Minimum code to make it work

89. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 89
public function buy($argument1)
{
// TODO: write logic here
}
Minimum code to make it work

90. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 90
public function buy(string $item)
{
$this->funds = $this->funds -
$this->catalog->howMuchIsA($item);
}
Minimum code to make it work

91. public function buy(string $item)
{
$price = $this->catalog->howMuchIsA($item);
$this->funds -= $price;
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 91
Make code simpler and clearer

92. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 92

93. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 93
function it_returns_coins(CoinReturn $coinReturn)
{
$this->insertCoin(5);
$this->returnCoins();
$coinReturn->returnPence(5)
->shouldHaveBeenCalled();
}
Use examples to describe behaviour

94. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 94
function it_returns_coins(CoinReturn $coinReturn)
{
$this->insertCoin(5);
$this->returnCoins();
$coinReturn->returnPence(5)
->shouldHaveBeenCalled();
}
Use examples to describe behaviour

95. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 95
function let(Catalog $catalog, CoinReturn $coinReturn)
{
$this->beConstructedWith($catalog, $coinReturn);
}
Let $this be constructed with

96. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 96
private $catalog;
public function __construct(
Catalog $catalog
) {
$this->catalog = $catalog;
}
Minimum code to make it work

97. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 97
private $catalog;
private $coinReturn;
public function __construct(
Catalog $catalog, CoinReturn $coinReturn
) {
$this->catalog = $catalog;
$this->coinReturn = $coinReturn;
}
Minimum code to make it work

98. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 98
public function returnCoins()
{
// TODO: write logic here
}
Minimum code to make it work

99. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 99
public function returnCoins()
{
$this->coinReturn->returnPence($this->funds);
}
Minimum code to make it work

100. Make code simpler and clearer
public function returnCoins()
{
$this->coinReturn->returnPence($this->funds);
}
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 100

101. @dave1010 - #phpsc16 - joind.in/talk/f4771 - 101

102. PhpSpec is a design tool
● Behaviour of objects
● Object collaboration
(sending and receiving messages through interfaces)
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 102

103. PhpSpec does lots more
● More matchers: ->shouldHaveType()
● Matching exceptions: ->shouldThrow()
● Matching wildcard arguments: Argument::any()
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 103

104. PhpSpec does even more
● Custom matchers
● Code templates
● Extensions
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 104

105. 4 Pro tips
1.
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 105

106. Refactor
No refactoring (slow to a standstill)
R G|R_ G_|R__ G__|R___ G___|R______ G______
Refactoring (keep up pace)
R G R|R G R|R G R|R G R|R G R
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 106

107. 4 Pro tips
1. Refactor
2. Use interfaces when calling methods on
other objects
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 107
Refactor

108. 4 Pro tips
1. Refactor
2. Use interfaces when calling methods on
other objects
3. Painful to spec means you have a bad design
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 108
Refactor

109. 4 Pro tips
1. Refactor
2. Use interfaces when calling methods on
other objects
3. Painful to spec means you have a bad design
4. Refactor !
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 109
Refactor
Refactor

110. Thanks!
● Questions?
● joind.in/talk/f4771
Dave Hulbert, @dave1010
Engineering director, @wearebase
Organiser, @phpdorset
@dave1010 - #phpsc16 - joind.in/talk/f4771 - 110