Unit tests pass when I change the order of tests - php

In my unit tests, I am using the following getDataSet method to set up DB. the test class extends from extends PHPUnit_Extensions_Database_TestCase
It looks like the framework is not deleting the and re inserting the rows before each test. The reason I feel that way is because my tests are passing when I change the order of some of the tests, which should never happen.
So Can anyone suggest what am I doing wrong .. or where should I look further to gain more insight ?
Also, I had to use composite Data Set as some of the older fixtures are in xml format, while new fixtures are in array format. Although no xml fixtures needs for this one.
public function getDataSet()
{
$compositeDs = new PHPUnit_Extensions_Database_DataSet_CompositeDataSet();
/** #var PHPUnit_Extensions_Database_DataSet_FlatXmlDataSet $ds */
$arrayDS = new ArrayDataSet([
__DIR__ . '/seed-data/companies.php',
]);
$compositeDs->addDataSet($arrayDS);
return $compositeDs;
}
Could it be because I save pdo connection and reuse it ? as in follows
final public function getConnection()
{
if ($this->conn === null) {
if (self::$pdo == null) {
self::$pdo = new PDO($GLOBALS['DB_DSN'], $GLOBALS['DB_USER'], $GLOBALS['DB_PASSWD']);
}
$this->conn = $this->createDefaultDBConnection(self::$pdo, $GLOBALS['DB_DBNAME']);
}
return $this->conn;
}

getDataSet is called before every test, so every test your database-tables will be truncated and inserted with the provided data.
That's why the order of your tests doesn't matter.

Related

Replace all class instances with stub

I am testing a class, let's call it ClassUnderTest using another class, let's call it OtherClass. In my Test I do:
$OtherClassStub = $this->createStub(OtherClass::class);
$OtherClassStub->method(...)
->willReturn(...);
$ClassUnderTest->otherClass = $OtherClassStub;
That works. But when the $ClassUnderTest calls new OtherClass(), the original OtherClass class is created instead of the stub.
How can I achieve that every possible instance of OtherClass in the context of the test is replaced by the stub?
From your description I infer that in principle you have something like this:
class OtherClass {
protected function someMethod(): bool
{
// determine $x ...
return $x;
}
}
class ClassUnderTest {
public OtherClass $otherClass;
public function methodToBeTested(): bool
{
$otherClass = new OtherClass();
return $otherClass->someMethod();
}
}
class ClassUnderTestTest extends TestCase {
public function testMethodToBeTested(): void
{
$otherClassStub = $this->createStub(OtherClass::class);
$otherClassStub->method('someMethod')
->willReturn(true);
$classUnderTest = new ClassUnderTest();
$classUnderTest->otherClass = $otherClassStub;
$result = $classUnderTest->methodToBeTested();
$this->assertTrue($result);
}
}
Now the assertion in your test may hold or it may fail. Why? Because you are not calling the method you stubbed on the $otherClassStub. Instead you instantiate a new $otherClass object in the method you're testing (or somewhere down the line).
Either your ClassUnderTest should always use the OtherClass object from the ClassUndertTest::otherClass attribute (assuming that's why you put it there in the first place).
Or you could use some other form of dependency injection, e.g. by using a framework like Symfony or Laravel. (In the case of Symfony you can even use only the DependencyInjection Component, no idea if that's possible with Laravel, too.)
The simple answer to your actual question is: you cannot change the behaviour of the new keyword. Calling new on a class will always instantiate a new object based on exactly that class, unless the constructor of that class defines something else.
(You might want to get the concept of classes and objects straight, your code example as well as your question seem to indicate that you're not quite clear on that. Maybe reading up on that as well as on the concept of dependency injection will help you.)
Perhaps a solution to your problem is presented here:
How to Build a PHP Plugin Module System
This is one way to load classes as plugins and they can be called from each other. With modifying this system a bit, you can create as many "new OtherClass()" as you like from your code and still access everything from other classes. If you want multiple instances of a class, perhaps modify it into this direction:
function load ($module,$instance) {
if (isset($this->$module->$instance)) { return true; }
From above link:
<?php
class Core {
// (A) PROPERTIES
public $error = ""; // LAST ERROR MESSAGE
public $pdo = null; // DATABASE CONNECTION
public $stmt = null; // SQL STATEMENT
public $lastID = null; // LAST INSERT/UPDATE ID
// (B) LOAD SPECIFIED MODULE
// $module : module to load
function load ($module) {
// (B1) CHECK IF MODULE IS ALREADY LOADED
if (isset($this->$module)) { return true; }
// (B2) EXTEND MODULE ON CORE OBJECT
$file = PATH_LIB . "LIB-$module.php";
if (file_exists($file)) {
require $file;
$this->$module = new $module();
// EVIL POINTER - ALLOW OBJECTS TO ACCESS EACH OTHER
$this->$module->core =& $this;
$this->$module->error =& $this->error;
$this->$module->pdo =& $this->pdo;
$this->$module->stmt =& $this->stmt;
return true;
} else {
$this->error = "$file not found!";
return false;
}
}
}
ps. thank you for the mod, who made me work a bit more to keep this answer online. the answer is so much better now.

Singleton v Single Instance DB Connection in PHP

I'm moving onto teaching myself OOP in PHP.
I'm creating a couple of little web apps and have followed a lot of tutorials that either create the database (using PDO) via a Singleton, or via passing the global around. I've read that these are pretty much the same thing and are both to be avoided like the plague.
So I've watched the Google Tech Talks on clean code, and read almost every SO article on dependency injection and the like. I have a couple of questions.
The clean code videos suggest you shouldn't do 'work' in your constructors. Is this 'work' in reference to business logic. Ie. If my class's job is to create another object, is that an OK kind of 'work'?
For example, in trying to conform to single repsonibility classes I created three.
Class DB - which actually connects to the database.
Class DBFactory - which creates the DB object which connects to the database.
Class DBInstance - which returns a single instance of the DBFactory created PDO object.
Please note that I'm trying to create a single instance, without creating a Singleton pattern.
So I try and pass my dependencies for each class up the chain. I find myself in a position where I have to create all of the objects (from DB down) so I can inject the dependencies. For some reason I thought it would work the other way, I'd create the first object, which would create the second for me etc. I'm clearly missing something?
Hopefully this helps others as well - there seems to be a myriad of questions relating to this stuff and databases but very little good examples.
(I should mention this does work, I do get a list of hotel names out of the database!)
TestCode.php
include './classes/DB.php';
include './classes/DBFactory.php';
include './classes/DBInstance.php';
include './classes/Location.php';
$db = new DB;
$dbfactory = new DBFactory($db);
$dbinstance = new DBInstance($dbfactory);
$dbh = $dbinstance->getDbInstance();
//Example business logic
$location_names = Location::getLocationNames($dbh);
print_r($location_names);
Class DB.php:
class DB {
private $_dbhost = 'myhost';
private $_dbname = 'myname';
private $_dbuser = 'myuser';
private $_dbpass = 'mypass';
private $_error;
public function connect() {
try {
return new PDO("mysql:host=$this->_dbhost;dbname=$this->_dbname",
$this->_dbuser, $this->_dbpass);
}
catch (PDOException $e) {
$this->_error = 'Error! ' . $e->getMessage() . '<br />';
die();
}
}
public function getError() {
if (isset($this->_error)) {
return $this->_error;
}
}
}
Class DBFactory.php
class DBFactory {
private $_dbh;
public function __construct(DB $db) {
$this->_dbh = $db;
}
public function Create() {
return $this->_dbh->Connect();
}
}
Class DBInstance.php
class DBInstance {
private static $_dbinstance;
public function __construct(DBFactory $dbfactory) {
if (!isset(self::$_dbinstance)) {
self::$_dbinstance = $dbfactory->Create();
}
}
public function getDbInstance() {
return self::$_dbinstance;
}
}
Your code seems to do what you want it to.. but maybe we can use less object instantiation using inheritance and maybe we can avoid static properties in instanciated classes.
Also in regard to using a pattern of dependency injection that is able to handle multiple connections, but support using a single instance of it. exemple first, classes after
$params = array
('host'=>'localhost',
'db'=>'ice',
'user'=>'kopitar',
'pass'=>'topnet',
'charset'=>'utf8'); // passing the charset explicitely is great
$handle = new handle($params);
$db = $handle->getInstance();
we can either pass the $db to our functions
$location_names = Location::getLocationNames($db);
or the whole $handle. as long as $handle is not reconstructed, it will always return the same database connection.
$location_names = Location::getLocationNames($handle);
if I want to reconstruct I need the whole $handle
$handle->__construct(/* params but with another database infos */);
$db2 = $handle->getInstance();
As for the classes, I think we want the params to arrive from the instanciated class, so we can change them later.
class db {
function __construct($params) {
foreach ($params as $param => $value) {
$this->{$param} = $value; // assigns the connections infos
}
}
protected function connect() {
$dsn = 'mysql:host='.$this->host.';dbname='.$this->db.';charset='.$this->charset;
return new PDO($dsn,$this->user,$this->pass);
}
}
the factory creates a connection from params and passes it to something else, good factory
class factory extends db {
protected function create() {
return $this->connect();
}
}
now we want to have our object to keep it's connection as long as we do not rebuild it. so we give it to instance
class instance extends factory {
function instantiate() {
$this->instance = $this->create();
}
}
and last but not least, our handle which returns the instance. it could be in instance class.....................
but I feel like having four and find no real reason not to.
class handle extends instance {
function __construct($params) {
db::__construct($params);
$this->instantiate(); // when we construct a handle, we assign an instance to the instance property
}
function getInstance() {
return $this->instance;
}
}
KISS
Don't make things more complex than they are, of course this is just my opinion, but as I see it you are building a complex solution for a problem that someone else says might exist is some cases.
Php is not multi threaded so there goes one of the biggest arguments overboard. (in very rare-occasions it might be)
I'm using singletons for my database connections for about 15 years now and never ever had a problem with them, I do play around with different connections having one singleton handle several connection instances, but whatever... it works great and everyone that looks at the code.. understands it directly.
I'm not using globals because they can be overwritten and are kind of hard to predict (when it holds the correct object, and when/why they don't)
Use OOP to make your code cleaner, easier to work with and more flexible.
Don't use it to fix problems that aren't there and make your code more complex because others tell you to.
An very simple example of a db-connection singleton class handling several different connections.
class singleton{
private static $_instances=array();
public static function getInstance($connectionName){
if(!isset(self::$_instance[$connectionName]){
self::$_instance[$connectionName]=self::_getConnection($connectionName);
}
return self::$_instance[$connectionName];
}
}
just my 2 cents
Why do you have a factory if you have a singleton? This is needless.
This is a never-ending debate, but I'm advocate of do not use singletons for database connections.
As far as in most applications, you have only one data channel, you can consider your database connection unique, but this might not be always true.
In deed, the effort made to create a singleton database connection is even bigger than just create a regular one.
Also, your class DB is not configurable, therefore, you need to change it when your connection parameters change. And I think DB is a very bad name for this.
I'd rather call this Storage and do something like:
inteface Storage {
public function insert($container, array $data);
public function update($container, array $data, $where);
public function delete($container, $where);
public function getAll($container);
public function getOne($identifier);
}
final class PdoStorage implements Storage {
private $dbh;
private $dsn;
private $user;
private $pswd;
public function __construct($dsn, $user, $pswd) {
$this->dsn = $dsn;
$this->user = $user;
$this->pswd = $pswd;
}
// Lazy Initialization
private function connect() {
if ($this->dbh === null)
$this->dbh = new PDO($this->dsn, $this->user, $this->pswd);
}
public function insert($container, array $data) {
$this->connect();
// ... omitted for brevity
}
}
Now, when you need a database storage, you do:
$someObj = new SomeClass(new PdoStorage(...));
Now you might be wondering if you will need to create an PdoStorage for each single object that depends on it.
The answer is: no!
Now you can use a factory to simplify your life.
class SomeFactory {
private $defaultStorage;
public function __construct(Storage $storage) {
$this->defaultStorage = $storage;
}
public function create($type) {
// Somehow fetches the correct class to instantiate and put it into $class variable , for example... and then
return new $class($this->defaultStorage); // Or you'd better do this with reflection
}
}
$factory = new SomeFactory(new PdoStorage(...));
$factory->create('SomeClass');
This way, you can have just one database connector or more if you need.

how to pass data mapper between models in php

I have read a lot in the past few days about domain objects, data mappers, and a bunch of other stuff I had no idea about.
I have decided to try and implement this in a bit of code I am writing (partly for learning purposes, and partly because I want to create a REALLY simplified framework to build a few projects quickly...with code that I can easily understand and modify).
After reading this and this, I was planning on creating a SINGLE data mapper, with a connection to the DB inside of it, and then use a factory to pass the data mapper into every domain object (well, the ones that would need it). I include some sample code below
class data_mapper {
private $dbh;
function __construct()
{
$this->dbh = new PDO(DB_STRING, DB_USER, DB_PASS);
}
public function createUser($data) ...
public function updateUser($user_id, $data) ...
public function createCategory($data) ...
}
class user {
private $data_mapper;
public $user_id;
public $data;
function __construct($dm)
{
$this->data_mapper = $dm;
}
function someFunction() {
/* some code */
$this->data_mapper->updateUser($user_id, $data);
/* some more code */
}
}
class factory {
private $data_mapper = null;
function __construct($dm)
{
$this->data_mapper = $dm;
}
public function create($name)
{
return new $name($this->data_mapper);
}
}
/* USAGE */
$dm = new data_mapper();
$factory = new factory($dm);
$user = $factory->create('user');
I am left with two questions:
A lot of recent examples I've looked at create a different data_mapper for each model. Should I be doing this? And if I do, wouldn't that make the factory much more complex (i.e. I would need to create single PDO object and pass that into each data mapper, and then pass the right data mapper into each model)?
If my above code exposes some flaw in the understanding of models, data mappers or anything else, please enlighten me (not really a question, i know)...
As far as I can tell, "data mapper" pattern implemented in modern frameworks in the form of prototype Model class, from which all application models are inherited.
In this prototype model you can implement CRUD methods and thus your models will possess it.
Speaking of passing pdo around, local scholars will tell you that you should pass PDO object as constructor parameter. But if you'll take a look at any modern framework - they are using some sort of singleton that contains a PDO instance
So, you want a REALLY simplified PHP framework. Data mappers sound like over-engineering.
Over the years i made a few KISS frameworks in PHP, this is what i did:
Use templates (aka view) such as Smarty. Great for outsourcing your webdesign.
Make a folder named pages (aka controller). Pages are called by index.php only.
Make a folder named models. Only models talk with your DB.
Make a index.php (aka router). Has a ?page=dog parameter.
Strict MCV (aka MVC) terminology is not the holy grail, the above is a nice implementation for a simple website/app/CMS.
The parts
/pages/page_dog.inc.php
A page loads the model(s) he needs, manipulates and shows it:
<?php if(!defined('YOURFRAMEWORK')){die('External access denied');}
// Page init
require './models/model_dog.inc.php';
$id = $_GET['id']; // todo fix injection attacks
$ModelDog = new ModelDog($DB);
// Page main
$ModelDog->Load($id);
echo $ModelDog->item['breed'];
For listings (a page where user selected the $id) you may not want seperate models representing each result. Make a lister class instead, much like the model but returning multiple items in one array. Its tempting to DRY and make the ListerDog class use the ModelDog but there is no readability gain just performance pain.
/index.php (aka router) calls a page (via require_once()) after auth and init ($DB):
<?php
define('YOURFRAMEWORK', 1); // disable "External access denied" error.
require_once('config.inc.php'); // todo have this hold the $config[] array.
$DB = #new mysqli( // or your derative, so you can log each query() call.
$config['db']['host'],
$config['db']['user'],
$config['db']['pasw'],
$config['db']['database']
);
if ($DB->connect_error) { die('db error: ' . mysqli_connect_errno()); }
// Load page requested by user. For now, its dog hardcoded.
require_once('./pages/page_dog.inc.php');
$DB->close;
/models/model_dog.inc.php (aka model) talks to the DB for you, processes and sanitizes data. I also use this put form processing functions.
<?php if(!defined('YOURFRAMEWORK')){die('External access denied');}
class ModelDog extends BaseModel {
private $tablename = 'dogs';
/**
* Load last (or specific) item.
* #param integer $id
* #return boolean Returns false when failed.
*/
public function Load($id=null) {
$query = "SELECT * FROM `".$this->tablename."` WHERE `id`='".$this->DB->Sanitize($id)."';";
// TODO .. $this->item =
}
public function ItemDefaults() {
return array(
'id' => 0,
'breed' => 'unknown',
'height' => 0
);
}
// TODO ..
}
/models/basemodel.inc.php extend every model class from something common like:
abstract class BaseModel
{
protected $item = array(); // Here is all the data!
protected $DB = null;
public function __construct($aQDB) {
parent::__construct();
$this->DB = $aDB;
$this->Reset();
}
public function Reset() {
$this->item = ItemDefaults();
}
public function Item() { return $item; }
// As seen in dog
abstract public function Load($id);
abstract public function ItemDefaults();
// But descendants (models) must also implement:
abstract public function Save($id = NULL);
abstract public function Delete($id);
// You may want to add Validate() and other internal things here.
}
All of the above is a bare-minimum version of what i build myself when i need another tiny framework. You gain more in proper subclassing than making more classes doing more things. A website is a simple thing in essence, until one overcomplicates it..
The gist / TLDR;
If you really want a REALLY simplified PHP framework, dont read to much. Just write code and you'll discover what it needs to make you work better.

Unsure if I'm using mockery correctly

I'm grappling with mocking/Mockery for the first time and I'm unsure if the following test is actually touching my code, or is only testing the mock I've made? Also, I realize this code doesn't properly fit the repository pattern despite the fact it's name as such.. I'll work on that.
The class:
<?php namespace Acme\Cart\Repositories;
class EloquentCartRepository{
protected $model_name = 'CartModel';
protected $model;
public function __construct($model = null)
{
$this->model = is_null($model) ? new $this->model_name : $model;
}
public function create_visitor_cart($session_id,$type = 'main'){
return $this->create('visitor',$session_id,$type);
}
protected function create($user_type = null,$user_identifier = null,$type = 'main')
{
if(is_null($user_identifier)) throw new \Exception('Cannot create create cart, missing user identifier');
if(is_null($user_type)) throw new \Exception('Cannot create create cart, missing user type');
if($user_type == 'visitor')
{
$this->model->user_session_id = $user_identifier;
}
else
{
$this->model->user_id = $user_identifier;
}
$this->model->type = $type;
$this->model->save();
return $this->model;
}
}
And my test:
/** #test */
public function create_visitor_cart_calls_internal()
{
$model = m::mock('Models\CartModel');
$model->shouldReceive('user_session_id')->with('sess123');
$model->shouldReceive('type')->with('main');
$model->shouldReceive('save')->andReturn($model);
$repository = new EloquentCartRepository($model);
$created_model = $repository->create_visitor_cart('sess123','main');
$this->assertEquals('sess123',$created_model->user_session_id);
$this->assertEquals('main',$created_model->type);
}
Is this a proper way to test my class? Or is this incorrect use of Mockery/mocking?
Instead of testing what is returned, you should test that it is saved. That means, that ->save() is run. The expectation you've set on ->save() is $model->shouldReceive('save')->andReturn($model);. That doesn't make sense, since the code doesn't use the return value of ->save().
In programming, you usually deal with 2 types of method: Commands and Queries. Queries can get some value, do some logic and return a value. Commands can get some values, communicates with an extern source (e.g. a database) and return nothing. Queries should be stubbed (that means, they should not do any expectations on how much it is called, but only on what it returns) and commands should be mocked (that means, they should only contain expectatations on how much (and if) it is called).
The ->save() method is a command: It communicates with the database. So it should be mocked. To mock the object, use the ->once() method of Mockery. It sets an expectation that it should be called one time:
/** #test */
public function create_visitor_cart_calls_internal()
{
$model = m::mock('Models\CartModel');
$model->shouldReceive('save')->once();
$repository = new EloquentCartRepository($model);
$created_model = $repository->create_visitor_cart('sess123','main');
$this->assertEquals('sess123',$created_model->user_session_id);
$this->assertEquals('main',$created_model->type);
}
Despite its name, Mockery is a stubbing framework by default. It does not validate that a method is called unless you explicitely specify an expectation like ->once()
For more information, see the docs: https://github.com/padraic/mockery-docs/blob/master/reference/expectations.rst

Zend Framework, PHPUnit and transactions

i want to use PHP Unit inside a Zend Framework application. I need to make several database writing operations inside the tests.
I want to start an MySQL transaction in the setUpBeforeClass() method. That is possible, but if I try to rollback the transaction in the tearDownAfterClass() method he throws an exception with the message 'There is no active transaction'. And the test methods does the writing operations in the database.
But if i start the transaction in the test method itselfs. It works like I want.
I don't understand why it reacts like this. Knows anyone an explanation?
<?php
class ConferenceControllerTest
extends PHPUnit_Framework_TestCase
{
/**
* A database connection.
* #var Zend_Db_Adapter_Pdo_Mysql
*/
protected static $hostDb = null;
public static function setUpBeforeClass()
{
static::$hostDb = Zend_Registry::get('db_host');
static::$hostDb->beginTransaction();
// The transaction for the Adapter is activated. But not inside the tests anymore.
}
public function testTest1()
{
// At this position teh transaction is not setted anymor? Why?
static::$hostDb->beginTransaction();
$sql = 'INSERT INTO test(test) VALUES(5);';
static::$hostDb->exec($sql);
}
public static function tearDownAfterClass()
{
try
{
static::$hostDb->rollBack();
}
catch(Exception $exception)
{
$message = $exception->getMessage();
Zend_Debug::dump($message);
}
}
}
I think you may be running into phpUnit's feature to backup statics and other globals between each unit test, see the "globals" section of the Fixtures chapter of the manual
The quick-hack fix would be to add this line, in the comments just above your class:
* #backupStaticAttributes disabled
That still leaves you with the xUnit Patterns book would call a nasty smell. I'm assuming you have a few testXXX functions that you expect to run in a certain order, each depending on the result of the previous one? That requires using #depends on each function, and it is easy to get wrong.
The alternative approach is a single long unit test function, and put the DB code in setUp() and tearDown():
public function setUp()
{
$this->db = Zend_Registry::get('db_host');
$this->db->beginTransaction();
}
public function tearDown()
{
try
{
$this->db->rollBack();
}
catch(Exception $exception)
{
$message = $exception->getMessage();
Zend_Debug::dump($message);
}
public function testTestVariousDBActions()
{
$sql = 'INSERT INTO test(test) VALUES(5);';
$this->db->exec($sql);
//another DB action
$this->assertEquals(...)
//another DB action
$this->assertEquals(...)
//...
}
The advantage of this is that if any assert fails none of the subsequent ones will be attempted. But tearDown() will always be called so the database is restored.
The disadvantage could be you get a Very Long Function. Use refactoring to deal with this (e.g. if you really want each action and its test in its own function, refactor so it looks like that and have testTestVariousDBActions() call each of them in turn).

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