PHPUnit - multiple stubs of same class - php

I'm building unit tests for class Foo, and I'm fairly new to unit testing.
A key component of my class is an instance of BarCollection which contains a number of Bar objects. One method in Foo iterates through the collection and calls a couple methods on each Bar object in the collection. I want to use stub objects to generate a series of responses for my test class. How do I make the Bar stub class return different values as I iterate? I'm trying to do something along these lines:
$stubs = array();
foreach ($array as $value) {
$barStub = $this->getMock('Bar');
$barStub->expects($this->any())
->method('GetValue')
->will($this->returnValue($value));
$stubs[] = $barStub;
}
// populate stubs into `Foo`
// assert results from `Foo->someMethod()`
So Foo->someMethod() will produce data based on the results it receives from the Bar objects. But this gives me the following error whenever the array is longer than one:
There was 1 failure:
1) testMyTest(FooTest) with data set #2 (array(0.5, 0.5))
Expectation failed for method name is equal to <string:GetValue> when invoked zero or more times.
Mocked method does not exist.
/usr/share/php/PHPUnit/Framework/MockObject/Mock.php(193) : eval()'d code:25
One thought I had was to use ->will($this->returnCallback()) to invoke a callback method, but I don't know how to indicate to the callback which Bar object is making the call (and consequently what response to give).
Another idea is to use the onConsecutiveCalls() method, or something like it, to tell my stub to return 1 the first time, 2 the second time, etc, but I'm not sure exactly how to do this. I'm also concerned that if my class ever does anything other than ordered iteration on the collection, I won't have a way to test it.

I'm unfortunately not sure if you can solve your actual question using getMock(), but my experience with getMock() itself is slim.
Only thing I can think of offhand, but not knowing your Bar class, this may not help: The third parameter of getMock() lets you pass constructor arguments (as an array).
I'd create my own mock class extending Bar as a test helper (fancy name for 'just another class that so happens to be used only in tests') that does exactly what I like and inject a series of them into your Foo object. That gives you all the control you'd want, since you can outright replace the methods in question, which getMock() does not do. Of course that also means you're not testing the Bar class in this test, which may not be what you want - though I'd recommend writing a separate test class per tested class anyway, but there are cases where that's unnecessarily purist.
$stubs = array();
foreach ($array as $value) {
$stubs[] = new MyBarTestHelper($value);
}
That aside, I'm honestly surprised you're only seeing the exception described when you have more than one array element. I've observed that PHPUnit actually expects you to declare any method you want it to be able to track as a getMock() parameter, and will stolidly error out otherwise, since essentially what it does internally is create its own extension of the class, wrapping each method that you expressly declare with logic that lets it determine whether it was called (= adding the method name into a logical list).
So colour me naive (seriously, I probably am, I'm a test newbie, myself), but see if this helps you any:
$stubs = array();
foreach ($array as $value) {
$barStub = $this->getMock('Bar', array('GetValue'));
$barStub->expects($this->any())
->method('GetValue')
->will($this->returnValue($value));
$stubs[] = $barStub;
}

This should satisfy the requirement to return a series of values in order as it's called if you're comfortable with the use of global. It has no idea which Bar is called but if each Bar is called by Foo once in order then it shouldn't be too hard to populate the test data.
$barTestData = array('empty',1,2,3,4,5,6);
function barDataCallback(){
global $barTestData;
return next($barTestData);
}

I noticed you have an extra parenthesis after "->method('GetValue')" in your code. Don't know if you copied and pasted that or not.

Related

PHP callback: Is there an equivalent for ::class for a method of a class?

In PHP it is possible to get a full class name via class name resolution like this:
Example:
namespace Name\Space;
class ClassName {}
echo ClassName::class;
Output: Name\Space\ClassName
This is better than using the string Name\Space\ClassName directly in the code because code introspection especially in IDEs can find an error directly.
I wonder if there is something similar for methods of a class - this would be specifically useful for callback functions.
This is how you can basically can pass a callback:
$a = function($callback,$arg) { return $callback($arg); }
$a('getInfo',5);
Instead of passing a string here (which might change), I would prefer to do something like this:
$a(MyClass::class::getInfo,5);
With I "go to declaration" click in the IDE I could go directly to getInfo plus I see errors in case with method does not exist anymore. Is there a way to achieve what I want to do here?
In fact, you work with callable type. And PHP allows setting method/function name only as a string. But if you use classes and objects you will have a different way to set callback. For example:
$a = function($callback, $arg) {
return call_user_func($callback, $arg));
}
// call a static method of the class with
// using fullname space and method name as a string
$a('Name\Space\MyClass::getInfo',5);
// call a static method of the class
// with using ::class
$a([MyClass::class, 'getInfo'], 5);
// call a method of an object
$myObject = new MyClass();
$a([$myOject, 'getInfo'], 5);
Three possibilities.
(1)
echo `__CLASS__`;
...returns namespace\classname as a string.
(2)
If you're trying to get the namespace\classname from another class, i.e., not the one where you're currently executing code, then I would suggest setting a public property inside each class such as:
public static $classname = __CLASS__;
which you could then access from anywhere as:
ClassName::$classname
Put it in each of your classes. Always use the same property name.
(3)
Have you considered the PHP function debug_backtrace() which returns a call stack with the most recent call at index = 0;
So, if:
$caller = debug_backtrace();
Then, $caller[0]['class'] contains the fully qualified class name, including any namespace, at the point where you called debug_backtrace().
I'm guessing that #2 is the solution that will work for you.
Just thought of a 4th possibility that doesn't depend on you adding any code to each class. Might add some overhead though, but so does my 3rd solution above.
(4)
$declared_classes = get_declared_classes();
This lists all of the classes currently declared within the PHP scope as fully qualified namespace\classname. You could search the returned array for partial string matches within the array and return the whole namespace\classname string.
One thing to keep in mind. You might have duplicates if different namespaces have same-named classes.
I've added this as a comment somewhere else but figured it might warrant an actual answer to this question. If you use:
$callback = [MyClass::class, 'myMethod'];
Then at least one IDE (PhpStorm) will recognize this as the callable that it is, allow you to navigate to it, mention it in "show usages" and automatically change it when it is renamed through a refactor. I use this in my code if, for instance, I reference a method in a test:
$this->mock(MyClass::class, function(MockInterface $mock) {
$mock->shouldReceive([MyClass:class, 'myMethod'][1])->andReturn(10);
});
Not the cleanest syntax, but it's workable.

How should I test this behavior using PHPUnit in CakePHP 3.0 ?

I have this method in BrandBehavior and I want to test it.
public function setCurrentBrandId(Entity $entity)
{
if (!isset($entity->brand_id) or empty($entity->brand_id)) {
$entity->brand_id = $this->session->read("Brand.id");
}
}
I want to test if this method actually sets the BrandID. Could You give me the example how should I test this ? So far I have covered basically nothing.
public function setUp()
{
parent::setUp();
$this->Progress = new BrandsBehavior();
}
public function testSetCurrentBrandId()
{
}
If you need anything else let me know and just so that you know that I am beginner with tests and testing.
First, behaviors don't usually have access to session ($this->session) - I assume you are injecting it somewhere. In this case you can mock the session object and test against that (you can read about mocking here).
Second, the method signature for \Cake\ORM\Behavior::__construct is Table $table, array $config = [] - this means that you need to change a bit the setUp method. This should give an idea.
Third, testing is about verifying that the function/method does what you expect it to do (based on input). So for actual tests you can give it two entities (one that has brand_id field and other that doesn't) and assertEquals the new value of the brand_id field after calling this method
Also, a couple of tips:
!$entity->has('field_name') is a shortcut for !isset($entity->brand_id) or empty($entity->brand_id)
Injecting your session object into a behavior is not a good idea. While it has an obvious use, I suggest that you either inject the actual value into the behavior or (if you need the function to read from session) move this to a component.
Instead of hardcoding "Brand.id" as a session key to read, consider having it as a config key

How to mock an argument that returns a new class in PHPUnit?

I'm having a problem with a line of code like:
$user->has('roles', ORM::factory('role', array('name' => 'unverified')))
I can mock the first argument, but can only assert that the 2nd argument returns a class. In some classes I make multiple uses of has and need to be able to test them properly. To be clear, I need to confirm that "unverified" was passed into the factory method of the 2nd argument. Any help is much appreciated.
The class I'm testing:
<?php
/**
* Policy class to determine if a user can upload a file.
*/
class Policy_File_Upload extends Policy
{
const NOT_LOGGED_IN = 1;
const NOT_VERIFIED = 2;
public function execute(Model_ACL_User $user, array $extra = NULL)
{
if ($user->can('login'))
{
return self::NOT_LOGGED_IN;
}
elseif ($user->has('roles', ORM::factory('role', array('name' => 'unverified'))))
{
return self::NOT_VERIFIED;
}
return TRUE;
}
}
and the corresponding test:
public function test_guest()
{
// User mock
$user = $this->getMock('Model_User', array('can', 'has'), array(), '', FALSE);
$user->expects($this->any())->method('can')->with('login')->will($this->returnValue(TRUE));
$user->expects($this->any())->method('has')->with('roles', $this->logicalOr
(
))
->will($this->returnCallback(array($this, 'roles')));
$policy = new Policy_File_Upload;
$this->assertSame(Policy_File_Upload::NOT_VERIFIED, $policy->execute($user));
}
You can always go the data-driven route of preparing test data for each case and verify the result of calling the function. In the end, you don't so much care that 'unverified' gets passed to ORM::factory() but rather that the correct result comes out of execute() based on the input.
Testing the implementation details makes the test brittle and difficult to write. If you can test the results instead, your tests won't break when you change how you arrive at the result. It may take longer to put together a data set for all your use cases, but it can generally be shared among tests.
To be clear, I need to confirm that "unverified" was passed into the factory method of the 2nd argument.
<?php
public function execute(Model_ACL_User $user, array $extra = NULL)
[...] ORM::factory('role', array('name' => 'unverified')) [...]
I'm sorry mate, you can't do that as there is no (sane) way to mock out a static method call.
The argument to why this is a problem are similar to one of Sebastian Bergmanns blog post: Testing-Code-That-Uses-Singletons
There are options like runkit that you could choose to replace the "ORM" class at runtime with a mocked version but thats really painfull.
So there are a couple of options:
You could create something like a Policy_File_Upload_Data_Provider that has a ->getRoles method where you put your ORM access. That would allow you to test your business logic nicely and testing that data access class should be a little easier as it doesn't to that much (just accessing the orm).
You could Inject your ORM class (or if that doesn't work out maybe just its name).
Depending on the class its self you should be able to create an instance and call ->factory like it would be a normal method. You could mock that.
If you don't want that just leaving that in there is also a not SO bad option.
Hope that at least gave you an idea/overview.
Additional Links why it's hard to test statics:
Misko Hevery - Flaw: Brittle Global State & Singletons
Kore Nordmann - Static considered harmful
You can actually do verification on parameters passed to mock methods utilizing parameter capturing in the Phake mocking framework for PHP.
public function test_guest()
{
// User mock
$user = Phake::mock('Model_User');
when($user)->can('login')->thenReturn(FALSE);
when($user)->has('roles', $this->anything())->thenGetReturnByLambda(array($this, 'roles'));
$policy = new Policy_File_Upload;
$this->assertSame(Policy_File_Upload::NOT_VERIFIED, $policy->execute($user));
Phake::verify($user)->has('roles', Phake::capture($factoriedRole));
$this->assertEquals('unverified', $factoriedRole->get('name'));
}
This example is assuming that you have the ability to check the name on $factoriedRole, obviously that piece needs to be changed depending on how that ORM stack works.
A small note, I agree with edorian regarding statics. If possible I would always prefer redesigning your code to not require statics, but sometimes that isn't possible, in which case this is a workable solution.
Phake Github Page
Phake Documentation on Parameter Capturing

Using a Setter with Multidimensional Arrays

I'm trying to create a __set for an object in PHP that works with multidimensional arrays. Is this even possible?
I would like to be able to something like the following: $post->comments[0]['uid']=3;. However, comments is actually going to be a key in a private cache variable $_cache['comments']=array(). It'd be nice if the __set function could somehow get both the base key (comments) and the index (0) as well as the key/value it is setting (uid/3). However, that's not possible.
I've thought about making $_cache['comments'] and array of ArrayObjects but that wouldn't let me define a custom _get/_set overload. Instead, I think that I might end up having to create a new Comments object and then fill the array with those. However, I really wouldn't like to do this and it'd be sweet if somehow PHP could handle nested arrays in __set overloads.
I'm using Mongo and would like if I could just have one single object for each document. However, arrays objects in Mongo are creating a bit of a problem for me. I would like to just handle them as an array in PHP but that doesn't seem possible. The setter needs to take $post->comments[0]['uid']=3 and update both the cache as well as setting $this->data['comments'][0]['uid']=3.
I know that if comments was an array of objects I could do this:
$post->comments[0]->uid=3;
///Sets $_cache['comments'][0]->uid=3;
And it would work because the getter for comments would return the array of objects and allow it to access the uid property. I could then have a getter/setter within the comments object that would somehow edit the $post->data through a pseudo "friend" function/hack. However, I don't see an easy way of accomplishing this with arrays....
Any advice?
That's more complex than you actually imagine. You can accomplish what you want with a heap of workarounds, but it's seldomly worth the effort.
If ->comments itself is resolved by a getter method, than assigning something to the [0] subarray won't actually end up in the private property. And ->comments[0]= will not even invoke your setter method. Instead this is a read access.
To make this work at all you would have to make your __get method return an reference of & $this->_cache['comments'].
If you want to intercept set accesses in that comments array you would indeed need ArrayObject. The difference is that this requires to override offsetGet and offsetSet instead of __get and __set. But again, since you are accessing a further subarray, the __get method will actually be used and you need to return another reference, or yet again a level of ArrayObject workaround goo.
I jumped through some of these hoops when building my own PHP wrapper class.
https://github.com/gatesvp/MongoModel
It's still in the the works, but it does handle some basic "map this object to DB".
There's virtually nothing worthwhile written in PHP chat rooms or the php documentation that's going to be useful to you, Adam. Most of the suggestions tend along the lines of implementing interface ArrayAccess or extending class ArrayObject, both in the SPL. In fact, there is a surprisingly straightforward solution to your problem: $post->comments[0]['uid']=3 using overloaded setter __set().
Define private $comments = array(); in class post. For convenience, use a text key for the first subscript of $comments: here, integer 0 becomes, say, "zero". You then invoke the setter as follows:
$post->zero = ['uid', 3];
This invokes the magic setter because there is no publicly declared property $zero in class post: "The overloading methods are invoked when interacting with properties or methods that have not been declared or are not visible in the current scope." (PHP 5 man page on Overloading.)
The setter can also be setComments(), a convenience because you won't have to discriminate among incoming properties to identify those intended for array comments, but the calling syntax becomes less natural.
Your overloaded, auto-magical function __set receives two arguments: a property and a value:
public function __set($property, $value) {
very reminiscent of Crockford's JSON protocol. It is helpful to think of it in those terms.
Since property "zero" that you sent in does not exist in classpost, it needs to be trapped, and my preferred method, since the first subscript in property comments will likely have several values, is to define a private array of supported subscript values in post:
private $indices = [
"zero" => 0,
"one" => 1,
"two" => 2,
"three" => 3
];
When the index for comments arrives in __set() as $property, it is verified to exist in $indices. Now you simply iterate through the array supplied in $value, extract
uid and its corresponding value, then assign to $comments as follows:
public function __set($property, $value) {
if (array_key_exists($property, $this->indices) && is_array($value))
foreach ($value as $uid => $uid_value)
$this->comments[$this->indices[property]][$uid] = $uid_value;
else
...
}
with $this->indices[property] being used to extract the integer value 0 to be used to
index the first dimension of comments, and $uid_value extracted with value int 3 to be assigned.
The approach outlined here is not a gimmick, workaround or clever trick. It's a straightforward design technique intended to work with one of SPL's facilities and can, in principle, be extended to arrays of arbitrary dimension. I have the design implemented in a production system so, if you're still having difficulty, post here and I'll help you to debug your application. Best of luck!
I believe the closest you can do for overloading some properties is to use the magic method __set() defined here: http://us.php.net/__set
I am not sure you can handle the [0] before it gets taken by the PHP compiler...
So your other solution would be to transform comments into a method
public function comments($id) {
return $this->obj[$id]; // Obj
}
And the object you return has the __set property
class Obj {
private $id;
public function __set($key, $value) {
if($key === 'uid') {
$_cache = $GLOBALS['_cache'];
$_cache['comments'][$this->id]->uid = $value;
}
}
}
There is a lot of code missing here, but you can figure out how to do it with this __set method()
Create a function instead of trying to hack it on top of something that isn't even meant for that.
public function setCommentUid($commentId, $uid) {
$this->_cache['comments'][$commentId]->uid = $uid;
}
//then...
$post->setCommentUid(0, 3);
This makes it much simpler to use the class and it's much easier to see what it does.

Php (eval vs call_user_func vs variable functions ...)

Even though there's some discussions regarding this issue I wanted to check on certain example what would be the best approach.
Instead of using existing solutions I created my own persistence layer (like many do)
So my approach is also in question here.
For every table in db I have model class that has appropriate getters and setters and some mandatory methods. I also created only one generic DAO class that handles all types of model objects.
So, for example to save any model object I instantiate genericDAO class and call save method that I pass model object as attribute.
Problem is that in runtime genericDAO class doesn't know whitch model object it gets and what methods (getters and setters) exist in it, so I need to call mandatory model class method that retrieves list of attributes as multiple string array.
For example for every attribute there's array(table_column_name,attribute_name,is_string).
When I call save function it looks like this:
public function save(&$VO) {
$paramArray = $VO->getParamArray();//get array of attributes
$paramIdArray = $paramArray[0]; //first attribute is always id
/*create and execute getId() and store value into $void to check if it's save or update*/
eval('$voId = $VO->get'.ucfirst($paramIdArray[1]).'();');
...
Currently I'm using eval to execute those methods, but as it is well known eval is very slow.
I'm thinking of changing that into call_user_func method
Something like:
$voId = call_user_func(array($VO, 'get'.ucfirst($paramIdArray[1])));
But also there's other solutions. I can maybe use something like this $method = 'get'.ucfirst($paramIdArray[1]));
$voId = $VO->$method();
or else
$method = 'get'.ucfirst($paramIdArray[1]));
$voId = $VO->{$method}();
What would be the best way?
First of all, there's no need to pass references like you are doing. You should give this a read to try to understand how PHP handles object references.
So public function save(&$VO) { should become public function save($VO) {.
Second, there is no need to use eval (in fact, it's better not to because of speed, debugability, etc). You can't stack-trace an eval call like you can a dynamic one.
Third, call_user_func is all but useless since PHP supports dynamic variable functions. Instead of call_user_func(array($obj, $method), $arg1), just call $obj->$foo($arg1). The call_user_func_array function is still useful since it supports variable length arguments and supports passing references.
So, ultimately, I would suggest this:
$method = 'get' . ucfirst($paramIdArray[1]);
$voId = $VO->$method();
Note that there's no need to call method_exists, since it may be callable and not exist due to __get magic method support...
I normally would use:
$method = 'get'.ucfirst($attribute);
if(method_exists($obj, $method){
$obj->$method();
}
But unless there is a very good reason i would just return a key => value array from getParamArray. And operate on that instead of using the getters...

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