Coding & Debugging
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Login Subscribephpspec just generated the __construct() method for us. Thanks buddy! Go check it out! Two cool things here. First, in Dinosaur, yes, it did add the constructor method. As a bonus, it even put it in the right place: after the properties, but above all the other public functions. phpspec, are you trying to take my job?
Second, when phpspec re-ran all of the examples, well... they're almost all failing now: too few arguments to Dinosaur::__construct(). And... that makes sense! We just massively changed the way that our Dinosaur class is designed. And so, any existing coding using that class will probably be totally borked! This is a great example of how our tests can give us feedback. They're saying:
Ryan! Do you realize that you just broke all of the code in your app that creates new
Dinosaurobjects???
If we did that on accident... well... that would be a pretty good warning to get.
Implementing the Constructor
Let's get to work: the first argument should be a string $genus and the second bool $isCarnivorous. I'll press Alt+Enter and select "Initialize Fields"... which is a shortcut to create those two properties and set them. Remove the TODO.
This is cool. But... I'm going to make both of these arguments optional. Why? Well, it's entirely up to you how you want your class to work. Look back at DinosaurSpec. According to this example, it looks like it should be legal to create a Dinosaur object with no information. If you do, the type should be "unknown" and it should default to not eat you... which is kinda nice. This is "design by spec": we're using our examples to drive how the class is built.
Default $genus to Unknown and $isCarnivorous to false.
| // ... lines 1 - 4 | |
| class Dinosaur | |
| { | |
| // ... lines 7 - 8 | |
| private $genus; | |
| // ... line 10 | |
| private $isCarnivorous; | |
| // ... line 12 | |
| public function __construct(string $genus = 'Unknown', bool $isCarnivorous = false) | |
| { | |
| $this->genus = $genus; | |
| $this->isCarnivorous = $isCarnivorous; | |
| } | |
| // ... lines 18 - 37 | |
| } |
Using --verbose
The getDescription() method is still wrong. But, we did just get a step closer, so let's try phpspec again:
./vendor/bin/phpspec run
Yep! The two strings don't match. By the way, see how it truncates the two strings? Sometimes that makes it hard to figure out what's going on. If you need more info, run phpspec with the --verbose option:
./vendor/bin/phpspec run --verbose
Back in Dinosaur, let's finish the getDescription() method. Wrap the string in sprintf() then add a few wildcards: one for the genus, one for the non- part and one for the length. Fill these in with $this->genus, a ternary to print either nothing, or non-, and then $this->length.
| // ... lines 1 - 28 | |
| public function getDescription(): string | |
| { | |
| return sprintf( | |
| 'The %s %scarnivorous dinsaur is %d meters long', | |
| $this->genus, | |
| $this->isCarnivorous ? '' : 'non-', | |
| $this->length | |
| ); | |
| } | |
| // ... lines 38 - 39 |
Oh, and let's make a typo to spice things up! Then, move over, take off the --verbose option and run spec:
./vendor/bin/phpspec run
It does fail... but... it's not exactly obvious why: the truncated strings look identical! This is when running with the verbose option is handy:
./vendor/bin/phpspec run --verbose
Much better - the typo is super obvious now. Fix that, then try it again:
./vendor/bin/phpspec run --verbose
Ah! It still fails! Whoops - I made a mistake in the spec file - but it's obvious. I've been using phpspec for so long that I can't avoid saying "should" in everything I type. Change should be to is: that's the language we want.
| // ... lines 1 - 28 | |
| public function getDescription(): string | |
| { | |
| return sprintf( | |
| 'The %s %scarnivorous dinsaur is %d meters long', | |
| // ... lines 33 - 35 | |
| ); | |
| } | |
| // ... lines 38 - 39 |
Try it one more time:
./vendor/bin/phpspec run
It passes! Next: with production ramping up, we need a factory for our dinosaurs. Let's see how we can describe that with phpspec.
