Laravel Package Development simple function does not work - php

Sorry for the bad title, but I had no idea to give a good title for my problem.
I created a package with the workbench. And now I have a package. Let's say strernd/mypkg
Inside the workbench directory Strernd/Mypkg I've got following code:
http://laravel.io/bin/oNzoa
Why does Mypkg::test()work and $mypkg = new Mypkg(); $mypkg->test(); not? (Inside my app)
The error is
Call to undefined method Strernd\Mypkg\Facades\Mypkg::test()Call to undefined method Strernd\Mypkg\Facades\Mypkg::test()
I think I'm not understanding some basic principles of PHP here. I'm more like a copy&paste / try&error "developer", but it works out well in most cases.

When using it the 'static' way, Laravel is accessing the facade you wrote and instantiating the underlying class, then calling the method on that instance. When you are calling the test method with new Mypkg, you are actually instantiating the facade class, and not the underlying class. That facade class does not have a test method on it, hence the error.
Try it like this:
use Strernd\Mypkg as MypkgActual;
$mypkg = new MypkgActual;
$mypkg->test();
I believe that, because your facade and actual class implementation have the same exact class name, you're running in to a pseudo-class name conflict with Laravel's facade system winning out. You can also try changing the name of your facade to MypkgFacade.

Related

PHPUnit gives error: Target [Illuminate\Contracts\View\Factory] is not instantiable

I created a simple test for my new Laravel 7 application. But when I run php artisan test I get the following error.
Target [Illuminate\Contracts\View\Factory] is not instantiable.
The error doesn't appear when I go to the page in the browser.
$controller = new HomeController();
$request = Request::create('/', 'GET');
$response = $controller->home($request);
$this->assertEquals(200, $response->getStatusCode());
Although "Just write feature tests" may seem like a cop-out ("They're not unit tests!"), it is sound advice if you do not want to get bogged down by framework-specific knowledge.
You see, this is one of those problems that come from using facades, globals, or static methods. All sorts of things happen outside of your code (and thus your test code) in order for things to work.
The problem
To understand what is going on, you first need to know how Laravel utilizes Containers and Factories in order to glue things together.
Next, what happens is:
Your code (in HomeController::home() calls view() somewhere.
view() calls app() to get the factory that creates Views1
app() calls Container::make
Container::make calls Container::resolve1
Container::resolve decides the Factory needs to be built and calls Container::build to do so
Finally Container::build (using PHP's ReflectionClass figures out that \Illuminate\Contracts\View\Factory can not be Instantiated (as it is an interface) and triggers the error you see.
Or, if you're more of a visual thinker:
The reason that the error is triggered is that the framework expects the container to be configured so that a concrete class is known for abstracts (such as interfaces).
The solution
So now we know what is going on, and we want to create a unit-test, what can we do?
One solution might seem to not use view. Just inject the View class yourself! But if you try to do this, you'll quickly find yourself going down a path that will lead to basically recreating loads of framework code in userland. So not such a good idea.
A better solution would be to mock view() (Now it is really a unit!). But that will still require recreating framework code, only, within the test code. Still not that good.[3]
The easiest thing is to simply configure the Container and tell it which class to use. At this point, you could even mock the View class!
Now, purists might complain that this is not "unit" enough, as your tests will still be calling "real" code outside of the code-under-test, but I disagree...
You are using a framework, so use the framework! If your code uses glue provided by the framework, it makes sense for the test to mirror this behavior. As long as you don't call non-glue code, you'll be fine![4]
So, finally, to give you an idea of how this can be done, an example!
The example
Lets say you have a controller that looks a bit like this:
namespace App\Http\Controllers;
class HomeController extends \Illuminate\Routing\Controller
{
public function home()
{
/* ... */
return view('my.view');
}
}
Then your test[5] might look thus:
namespace Tests\Unit\app\Http\Controllers;
use App\Http\Controllers\HomeController;
use Illuminate\Contracts\View\Factory;
class HomeControllerTest extends \PHPUnit\Framework\TestCase
{
public function testHome()
{
/*/ Arange /*/
$mockFactory = $this->createMock(Factory::class);
app()->instance(Factory::class, $mockFactory);
/*/ Assert /*/
$mockFactory->expects(self::once())
->method('make')
->with('my.view')
;
/*/ Act /*/
(new HomeController())->home();
}
}
A more complex example would be to also create a mock View and have that be returned by the mock factory, but I'll leave that as an exercise to the reader.
Footnotes
app() is asked for the interface Illuminate\Contracts\View\Factory, it is not passed a concrete class name
The reason Container::make does nothing other than call another function is that the method name make is defined by PSR-11 and the Laravel container is PSR compliant.
Also, the Feature test logic provided by Laravel already does all of this for you...
Just don't forget to annotate the test with #uses for the glue that is needed, to avoid warnings when PHPUnit is set to strict mode regarding "risky" tests.
Using a variation of the "Arrange, Act, Assert" pattern
This is not how you test endpoints in Laravel. You should let Laravel instantiate the application as it is already setup in the project, the examples you can see here.
What you already wrote can be rewritten to something like this.
$response = $this->call('GET', route('home')); // insert the correct route
$response->assertOk(); // should be 200
For the test to work, you should extend the TestCase.php, that is located in your test folder.
If you're finding this in The Future and you see #Pothcera's wall of text, here's what you need to know:
The ONLY reason he's doing any of that and the ONLY reason you're seeing this in the first place in a Unit test is because he and you haven't changed from PHPUnit\Framework\TestCase to Tests\TestCase in the test file. This exception doesn't exist when you extend the test case that includes app().
My advice would be to simply extend the correct base test case and move on with your life.

Pass class by config using ::class and retrieve in Laravel

I have a config file with such array:
'ppr' => [
'validate' => TestRequest::class
];
Now, I want to retrive this class in other part of the system and use it to validate form (outside of the controller).
While using config('main.ppr.validate') all I receive is namespaced name of the class instead of the class object.
As I already accepted that it won't be that easy to just use reuqests as in controllers, I still do wonder how to pass a class by config.
While passing eloquent models it works like a charm (or i.e. config arrays with middlewares etc.), so I suppose there is some magic binding to the IoC to achive that, is it true?
My question is, how to use class passed as in example above without initializing it like:
$obj = new $className;
Laravel (and many other applications) use Dependency Injection to achieve this magic -- your words, not mine! :D
It seems that the Service Container is what handles this in Laravel and should be of help to you.
Directly from the Laravel docs (linked above):
Within a service provider, you always have access to the container via the $this->app property. We can register a binding using the bind method, passing the class or interface name that we wish to register along with a Closure that returns an instance of the class:
$this->app->bind('HelpSpot\API', function ($app) {
return new HelpSpot\API($app->make('HttpClient'));
});
Also:
You may use the make method to resolve a class instance out of the container. The make method accepts the name of the class or interface you wish to resolve:
$api = $this->app->make('HelpSpot\API');
And:
If some of your class' dependencies are not resolvable via the container, you may inject them by passing them as an associative array into the makeWith method:
$api = $this->app->makeWith('HelpSpot\API', ['id' => 1]);
IMHO, I would look up where/how this is implemented in the native Laravel code (usually the Illuminate vendor) and see how it is used / meant to be implemented.
Furthermore, ClassName::class will return the namespace + class of that class. This is why you only see the class name and are not actually receiving an object/instance of that class.
I'm not sure what/where/why/how you're implementing your class and why you need this functionality somewhere that it doesn't already exist. Laravel is pretty good about already having things set up where you need them, so think twice before breaking out of the box and make sure there isn't a default solution for your situation!

Using the Scope Resolution Operator in Laravel

I'm confused about an aspect of OOP/Laravel.
I'm following an OOP tutorial (nothing to do with Laravel) that states that you can only use the Scope Resolution Operator when the method you are calling is static.
So I created a quick script;
class Student {
function welcome_students($var="Hello") {
echo "{$var} students.";
}
}
echo Student::welcome_students("Greetings") ."<br />";
And I get the error;
Strict Standards: Non-static method Student::welcome_students() should
not be called statically in /static_modifier.php on line 11 Greetings students.
But in Laravel 5, I've noticed that I've been using calls like
`ClassName::whereIn($var = `
in quite a few of my Controllers. I've checked the package where the whereIn method is stored and it's not static. It's just a public function.
So how is Laravel 5 allowing me to get away with it? I'm in development mode so I don't know why I'm not seeing that same message.
There are some fairly advanced concepts here that need to be understood in order to fully grasp how this is happening.
First, this would only work for the facades in Laravel. These can be found in the app.php config file in the aliases array. Each of these facades can be thought of as entry points for their real classes which are in the Laravel core. So even though the syntax is telling you that you are calling static methods, what's really happening is Laravel is resolving the underlying classes to these proxy classes and calling methods non-statically on those.
You can see this better if you go to some of those facade classes where you will see the methods you are calling are not actually present on those classes.
To really understand how this is happening, read up on Laravel's inversion of control container (IoC), its use of Facades, and the php magic method __callStatic, and the php method class_alias which is what Laravel is using to setup the aliases.
Again, these are fairly complex concepts so don't get discouraged if they seem confusing or the purpose eludes you.
Basically, the workflow looks like this...
You call Config::get()
Laravel looks up the alias for Config which is a facade.
Using the __callStatic magic method, the facade figures out the underlying class to instantiate and calls the appropriate method on that non-statically.
http://laravel.com/docs/5.0/facades#explanation
http://laravel.com/docs/4.2/ioc#introduction
http://php.net/manual/en/language.oop5.overloading.php#object.callstatic
First of all, your function is not static, you need change it if you want to call it like Student::welcome_students()
public static function welcome_students($var="Hello") {
echo "{$var} students.";
}

How to mock an Eloquent Model using Mockery?

I'm trying this:
$this->dsMock = Mockery::mock('Eloquent', 'API\V1\DataSet');
$this->app->instance('API\V1\DataSet', $this->dsMock);
$this->dsMock->shouldReceive('isLocalData')->once()->andReturn(true);
Then, inside the class under test:
$test = DataSet::isLocalData($dataSetId);
However, the DataSet class is not being mocked. It's still trying to access the database. Why?
The likely problem is Laravel's unfortunate over use of Façade's (which are also factories). If DataSet was already instantiated using the Façade, it will keep returning the same class, you won't get a mocked version.
I can't remember off hand if you can instantiate your class without using the Façade in Laravel. You have to remember that when you call DataSet statically in the application, you're actually not referencing API\V1\DataSet but something else that manages it.

Mock frameworks returns class with different name and type

I'm trying to create a mock to satisfy a typehint with this code (Mockery):
return \Mockery::mock('\Contracts\Helpers\iFileSystemWrapper');
or this (PHPUnit):
return $this->getMock('\Contracts\Helpers\iFileSystemWrapper');
But the mock returned is called Mockery\Mock Object or Mock_iFileSystemWrapper_a5f91049. How am I supposed to type check this when it isn't an instance of what I need at all with either framework?
Why exactly is the mock framework trying to load the real class? If I wanted the real class I would include the real class.
This problem has slowed me down so many times when writing tests I'm about to just toss type hinting out the window and check class names instead, or simply use production objects as mocks are a pain to use.
I just experimented with an existing test of my own, and by changing the interface namespace name from one that exists to one that doesn't exist, I got exactly the same as what you describe (using phpunit). My mock object had the class name Mock_ViewInterface_c755461e. When I change it back to the correct interface name, it works fine.
Therefore I would say that either:
You are trying to use an interface name that doesn't exist (e.g. a typo or missing namespace component).
Your library code isn't being loaded for some reason, e.g. autoloading is not setup correctly in your unit test bootstrap.
You need use a special function to check base class.
Somthing like this:
$mock = $this->getMock('MyClass');
$this->assertInstanceOf('MyClass', $mock);

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