From 2374bf4d0704a85d5ef81f88a9d9a5ef5dea0f15 Mon Sep 17 00:00:00 2001 From: Gunnar Wrobel Date: Wed, 16 Sep 2009 10:20:13 +0200 Subject: [PATCH] Added a trivial dependency injection framework named Horde_Provider. --- framework/Provider/COPYING | 504 +++++++++++++++++++++ framework/Provider/doc/Horde/Provider/usage.txt | 292 ++++++++++++ framework/Provider/lib/Horde/Provider/Base.php | 77 ++++ .../Provider/lib/Horde/Provider/Exception.php | 31 ++ .../Provider/lib/Horde/Provider/Injection.php | 40 ++ .../Provider/lib/Horde/Provider/Injection/Base.php | 50 ++ .../lib/Horde/Provider/Injection/Factory.php | 59 +++ framework/Provider/package.xml | 103 +++++ .../Provider/test/Horde/Provider/AllTests.php | 88 ++++ .../test/Horde/Provider/ProviderScenario.php | 110 +++++ .../Provider/test/Horde/Provider/ProviderTest.php | 195 ++++++++ 11 files changed, 1549 insertions(+) create mode 100644 framework/Provider/COPYING create mode 100644 framework/Provider/doc/Horde/Provider/usage.txt create mode 100644 framework/Provider/lib/Horde/Provider/Base.php create mode 100644 framework/Provider/lib/Horde/Provider/Exception.php create mode 100644 framework/Provider/lib/Horde/Provider/Injection.php create mode 100644 framework/Provider/lib/Horde/Provider/Injection/Base.php create mode 100644 framework/Provider/lib/Horde/Provider/Injection/Factory.php create mode 100644 framework/Provider/package.xml create mode 100644 framework/Provider/test/Horde/Provider/AllTests.php create mode 100644 framework/Provider/test/Horde/Provider/ProviderScenario.php create mode 100644 framework/Provider/test/Horde/Provider/ProviderTest.php diff --git a/framework/Provider/COPYING b/framework/Provider/COPYING new file mode 100644 index 000000000..d1c6b98aa --- /dev/null +++ b/framework/Provider/COPYING @@ -0,0 +1,504 @@ + GNU LESSER GENERAL PUBLIC LICENSE + Version 2.1, February 1999 + + Copyright 1991, 1999 Free Software Foundation, Inc. + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + +[This is the first released version of the Lesser GPL. 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Here is a sample; alter the names: + + Yoyodyne, Inc., hereby disclaims all copyright interest in the + library `Frob' (a library for tweaking knobs) written by James Random Hacker. + + , 1 April 1990 + Ty Coon, President of Vice + +That's all there is to it! + + diff --git a/framework/Provider/doc/Horde/Provider/usage.txt b/framework/Provider/doc/Horde/Provider/usage.txt new file mode 100644 index 000000000..4f8698b32 --- /dev/null +++ b/framework/Provider/doc/Horde/Provider/usage.txt @@ -0,0 +1,292 @@ +Introduction +============ + +Dependency injection +(http://en.wikipedia.org/wiki/Dependency_injection) is a useful design +pattern that can help to avoid using global variables or state. If a +class depends on a connection to a database then this connection is +often pulled into the class using a singleton pattern or by using a +global variable. + +Instead of providing the class with knowlegde about the global state +it is often preferable to "inject" the dependency into the class from +the outside. This usually happens within the class constructor. Thus +the dependencies of a class are immediately visible without searching +the code for references to the global scope. Another major benefit of +dependency injection is the fact that it facilitates unit testing of +complex systems. + +Horde_Provider +============== + +For PHP there exist several "Dependency Injection" frameworks +(e.g. http://stubbles.net, +http://components.symfony-project.org/dependency-injection) with +extensive feature lists. So there is hardly any need for another +framework with similar capabilities. + +The essential part of dependency injection is the structure of classes +with dependencies. They need to be amenable for an external management +of their dependencies. If that is the case for a given class then most +frameworks should have no problem handling this class within the +framework. The choice of the actual framework should not matter +anymore. + +In consequence Horde_Provider provides only a minimal version of +dependency injection that is mainly inspired by Twittee +(http://twittee.org/). The goal is to drive refactoring of classes +with complex dependencies so that they can be used with a dependency +injection framework. + +Making classes amenable to dependency injection +=============================================== + +As trivial as it may sound: a class can be managed by a dependency +injection framework if the class allows the framework to inject its +dependencies from the outside. That means that the class may *NOT* + + - pull in an dependency using global state via the singleton + pattern: + + External_Class::singleton()) + + - create new objects with dependencies: + + $db = new DB(); + $b = new User($db); + + - use global variables: + + if ($conf['a']) echo 'yes'; + +In most cases the class should receive dependencies and required +parameters within the constructor. + +Using Horde_Provider +==================== + +The Horde_Provider_Base class is a simple container that allows you to +fill it with a number of elements that can be retrieved later: + + $a = new Horde_Provider_Base(); + $a->a = 'a'; + echo $a->a; + + a + +Classes with dependencies are represented by registering a wrapper +object that implements the Horde_Provider_Injection interface: + + function factory() { return 'constructed'; } + $a = new Horde_Provider_Base(); + $b = new Horde_Provider_Injection_Factory('factory'); + $a->inject = $b; + echo $a->inject; + + constructed + +The example above demonstrates this approach by using the +Horde_Provider_Injection_Factory which implements +Horde_Provider_Injection. The class allows to register a callable +function. It will use this function to construct the required +object. Here the factory function is simple though and does not return +an object but a string. + +Preparing a class for Horde_Provider +==================================== + +Assume you have the following simple class that represents a common +structure found in many of the Horde packages: + + class Horde_X + { + /** + * Instance object. + * + * @var Horde_X + */ + static protected $_instance; + + /** + * Pointer to a DB instance. + * + * @var DB + */ + protected $_db; + + /** + * Attempts to return a reference to a concrete Horde_X instance. + * + * @return Horde_X The concrete Horde_X reference. + * @throws Horde_Exception + */ + static public function singleton() + { + if (!isset(self::$_instance)) { + self::$_instance = new Horde_X(); + } + + return self::$_instance; + } + + /** + * Constructor. + */ + public function __construct() + { + global $conf; + + $this->_db = DB::connect($conf['sql']); + } + } + +The class obviously depends on a database connection. The constructor +above does not allow for dependency injection as it constructs the +database connection itself. It uses the global variable $conf in order +to get the settings for this connection. A constructor allowing +dependency injection would look like this: + + /** + * Constructor. + * + * @param DB $db A database connection. + */ + public function __construct(DB $db) + { + $this->_db = $db; + } + +Of course this connection must be provided from somewhere. The +application using Horde_X might simply provide it when creating the +Horde_X instance. If the application is however using a dependency +injection framework then this framework would be required to provide +the required database connection. + +If the application uses Horde_Provider it would be necessary to +provide a factory method as Horde_Provider currently only allows to +call factory methods via Horde_Provider_Injection_Factory: + + /** + * Return a reference to a new Horde_X instance. + * + * @return Horde_X The new Horde_X reference. + */ + static public function factory($provider) + { + $x = new Horde_X($provider->db) + return $x; + } + +The fact that we need this factory method is a specific shortcoming of +the current capabilites of the Horde_Provider system. A more complex +dependency injection framework would have the ability to look at the +Horde_X constructor. It would then fetch the required dependencies +based on the constructor arguments. Type hinting is usually required +to inform the framework of the required dependency. In case of Horde_X +we used type hinting to indicate that we need an object of type "DB" +as parameter "$db". + +Getting rid of singletons? +========================== + +From the viewpoint of dependency injection Horde_X can be used now as +it allows external injection of its dependencies. We could throw away +the singleton now. There might be some reasons however why we would +like to keep the singleton() method. One of the reasons might be +backward compatibility as some other classes or applications are bound +to use the method. Another reason might be that we want to clarify how +to get a functional instance of the class to somebody just looking at +the Horde_X class. The factory method requires that there is a +$provider object "magically" providing the db connection. + +We could keep the following singleton method: + + static public function singleton() + { + if (!isset(self::$_instance)) { + global $conf; + + $provider = new stdClass; + $provider->db = DB::connect($conf['sql']); + self::$_instance = Horde_X::factory($provider); + } + + return self::$_instance; + } + +In this specific case it would probably be easier to directly use the +Horde_X constructor rather than the factory method but there might be +situations where the factory method has a higher complexity. + +We do not gain much here: The magic $provider->db parameter is +exchanged against the magic $conf['sql'] parameter. However the +singleton demonstrates how the DB class is instantiated via the +DB::connect() method. That is something that was not visible in the +factory method. + +A decent singleton method would require the database configuration as +a parameter for the method and refer to the DB class for details +concerning the possible configuration settings. That would however +break backward compatibility for the method. + +Result +====== + +The final result that can be used with a dependency injection +framework and still provides a backward compatible singleton method: + + class Horde_X + { + /** + * Instance object. + * + * @var Horde_X + */ + static protected $_instance; + + /** + * Pointer to a DB instance. + * + * @var DB + */ + protected $_db; + + /** + * Attempts to return a reference to a concrete Horde_X instance. + * + * @return Horde_X The concrete Horde_X reference. + */ + static public function singleton() + { + if (!isset(self::$_instance)) { + global $conf; + + $provider = new stdClass; + $provider->db = DB::connect($conf['sql']); + self::$_instance = Horde_X::factory($provider); + } + + return self::$_instance; + } + + /** + * Return a reference to a new Horde_X instance. + * + * @return Horde_X The new Horde_X reference. + */ + static public function factory($provider) + { + $x = new Horde_X($provider->db) + return $x; + } + + /** + * Constructor. + * + * @param DB $db A database connection. + */ + public function __construct(DB $db) + { + $this->_db = $db; + } + } diff --git a/framework/Provider/lib/Horde/Provider/Base.php b/framework/Provider/lib/Horde/Provider/Base.php new file mode 100644 index 000000000..7687f9551 --- /dev/null +++ b/framework/Provider/lib/Horde/Provider/Base.php @@ -0,0 +1,77 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * A trivial implementation of a provider. + * + * This class holds a set of elements that can be provided to an + * application. Special placeholder values of elements that are not instantiated + * yet implement the Horde_Provider_Binding interface. Such elements will get + * instantiated during retrieval by calling getInstance() on the binding + * object. The only argument to that call is the provider itself. The binding + * object can use this reference to retrieve any other elements it needs to + * correctly instantiate the desired object. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you did not + * receive this file, see + * http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. + * + * @category Horde + * @package Provider + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Horde_Provider_Base +{ + /** + * The set of elements handled by this container. + * + * @var array + */ + protected $elements; + + /** + * Set an element for this container. + * + * @param string $k The key of the element to set. + * @param mixed $v The element to set. + * + * @return NULL + */ + public function __set($k, $v) + { + $this->elements[$k] = $v; + } + + /** + * Get an element from this container. + * + * @param string $k The key of the element to retrieve. + * + * @return mixed The element. + */ + public function __get($k) + { + if (isset($this->elements[$k])) { + if ($this->elements[$k] instanceOf Horde_Provider_Injection) { + $this->elements[$k] = $this->elements[$k]->getInstance($this); + } + return $this->elements[$k]; + } else { + throw new Horde_Provider_Exception(sprintf("No such element: %s", $k)); + } + } +} \ No newline at end of file diff --git a/framework/Provider/lib/Horde/Provider/Exception.php b/framework/Provider/lib/Horde/Provider/Exception.php new file mode 100644 index 000000000..45407614e --- /dev/null +++ b/framework/Provider/lib/Horde/Provider/Exception.php @@ -0,0 +1,31 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * The standard exception for the Horde_Provider package. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you did not + * receive this file, see + * http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. + * + * @category Horde + * @package Provider + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Horde_Provider_Exception extends Horde_Exception +{ +} \ No newline at end of file diff --git a/framework/Provider/lib/Horde/Provider/Injection.php b/framework/Provider/lib/Horde/Provider/Injection.php new file mode 100644 index 000000000..c6680be65 --- /dev/null +++ b/framework/Provider/lib/Horde/Provider/Injection.php @@ -0,0 +1,40 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * The interface that describes the binding classes. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you did not + * receive this file, see + * http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. + * + * @category Horde + * @package Provider + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +Interface Horde_Provider_Injection +{ + /** + * Create an instance of the proxied object. + * + * @param Horde_Provider_Base $provider The class providing additional + * required dependencies. + * + * @return mixed The generated instance. + */ + public function getInstance(Horde_Provider_Base $provider); +} \ No newline at end of file diff --git a/framework/Provider/lib/Horde/Provider/Injection/Base.php b/framework/Provider/lib/Horde/Provider/Injection/Base.php new file mode 100644 index 000000000..27be12b37 --- /dev/null +++ b/framework/Provider/lib/Horde/Provider/Injection/Base.php @@ -0,0 +1,50 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * The basic definition for generating an elemnt. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you did not + * receive this file, see + * http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. + * + * @category Horde + * @package Provider + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Horde_Provider_Injection_Base implements Horde_Provider_Injection +{ + + protected $loading = false; + + /** + * Create an instance of the proxied object. + * + * @param Horde_Provider_Base $provider The class providing additional + * required dependencies. + * + * @return NULL + */ + public function getInstance(Horde_Provider_Base $provider) + { + if ($this->loading) { + throw new Horde_Provider_Exception('Element already loading!'); + } + + $this->loading = true; + } +} \ No newline at end of file diff --git a/framework/Provider/lib/Horde/Provider/Injection/Factory.php b/framework/Provider/lib/Horde/Provider/Injection/Factory.php new file mode 100644 index 000000000..c0665476f --- /dev/null +++ b/framework/Provider/lib/Horde/Provider/Injection/Factory.php @@ -0,0 +1,59 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * This class generates an element via a factory method. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you did not + * receive this file, see + * http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. + * + * @category Horde + * @package Provider + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Horde_Provider_Injection_Factory extends Horde_Provider_Injection_Base +{ + /** + * Constructor. + * + * @param mixed $factory A callable factory function. + */ + public function __construct($factory) + { + $this->factory = $factory; + } + + /** + * Create an instance of the proxied object via the factory method. + * + * @param Horde_Provider_Base $provider The class providing additional + * required dependencies. + * + * @return mixed The instance generated by the factory. + */ + public function getInstance(Horde_Provider_Base $provider) + { + parent::getInstance($provider); + + $instance = call_user_func($this->factory, $provider); + + $this->loading = false; + + return $instance; + } +} \ No newline at end of file diff --git a/framework/Provider/package.xml b/framework/Provider/package.xml new file mode 100644 index 000000000..91e755a21 --- /dev/null +++ b/framework/Provider/package.xml @@ -0,0 +1,103 @@ + + + Provider + pear.horde.org + A provider for dependency injection. + This module provides an extremely simplified approad to dependency + injection. + + + Gunnar Wrobel + wrobel + p@rdus.de + yes + + + Chuck Hagenbuch + chuck + chuck@horde.org + yes + + + Jan Schneider + jan + jan@horde.org + yes + + 2009-09-15 + + 0.0.1 + 0.0.1 + + + alpha + alpha + + LGPL + + * Initial release. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + 4.3.0 + + + 1.4.0b1 + + + Exception + pear.horde.org + + + + + + + + + + + + + + + + + diff --git a/framework/Provider/test/Horde/Provider/AllTests.php b/framework/Provider/test/Horde/Provider/AllTests.php new file mode 100644 index 000000000..9884a6257 --- /dev/null +++ b/framework/Provider/test/Horde/Provider/AllTests.php @@ -0,0 +1,88 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * Define the main method + */ +if (!defined('PHPUnit_MAIN_METHOD')) { + define('PHPUnit_MAIN_METHOD', 'Horde_Provider_AllTests::main'); +} + +/** + * The Autoloader allows us to omit "require/include" statements. + */ +require_once 'Horde/Autoloader.php'; + +/** + * Combine the tests for this package. + * + * Copyright 2007-2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you + * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html. + * + * @category Horde + * @package Provider + * @subpackage UnitTests + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Horde_Provider_AllTests +{ + + /** + * Main entry point for running the suite. + * + * @return NULL + */ + public static function main() + { + PHPUnit_TextUI_TestRunner::run(self::suite()); + } + + /** + * Collect the unit tests of this directory into a new suite. + * + * @return PHPUnit_Framework_TestSuite The test suite. + */ + public static function suite() + { + // Catch strict standards + error_reporting(E_ALL | E_STRICT); + + $suite = new PHPUnit_Framework_TestSuite('Horde Framework - Horde_Provider'); + + $basedir = dirname(__FILE__); + $baseregexp = preg_quote($basedir . DIRECTORY_SEPARATOR, '/'); + + foreach (new RecursiveIteratorIterator(new RecursiveDirectoryIterator($basedir)) as $file) { + if ($file->isFile() && preg_match('/Test.php$/', $file->getFilename())) { + $pathname = $file->getPathname(); + require $pathname; + + $class = str_replace(DIRECTORY_SEPARATOR, '_', + preg_replace("/^$baseregexp(.*)\.php/", '\\1', $pathname)); + $suite->addTestSuite('Horde_Provider_' . $class); + } + } + + return $suite; + } + +} + +if (PHPUnit_MAIN_METHOD == 'Horde_Provider_AllTests::main') { + Horde_Provider_AllTests::main(); +} diff --git a/framework/Provider/test/Horde/Provider/ProviderScenario.php b/framework/Provider/test/Horde/Provider/ProviderScenario.php new file mode 100644 index 000000000..335f69fb2 --- /dev/null +++ b/framework/Provider/test/Horde/Provider/ProviderScenario.php @@ -0,0 +1,110 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * The Autoloader allows us to omit "require/include" statements. + */ +require_once 'Horde/Autoloader.php'; + +/** + * Test the Horde_Provider class. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you + * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html. + * + * @category Horde + * @package Provider + * @subpackage UnitTests + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Horde_Provider_ProviderScenario extends PHPUnit_Extensions_Story_TestCase +{ + /** + * Handle a "given" step. + * + * @param array &$world Joined "world" of variables. + * @param string $action The description of the step. + * @param array $arguments Additional arguments to the step. + * + * @return mixed The outcome of the step. + */ + public function runGiven(&$world, $action, $arguments) + { + switch($action) { + case 'a provider': + $world['provider'] = new Horde_Provider_Base(); + break; + case 'a registered element': + $world['provider']->{$arguments[0]} = $arguments[1]; + break; + default: + return $this->notImplemented($action); + } + } + + /** + * Handle a "when" step. + * + * @param array &$world Joined "world" of variables. + * @param string $action The description of the step. + * @param array $arguments Additional arguments to the step. + * + * @return mixed The outcome of the step. + */ + public function runWhen(&$world, $action, $arguments) + { + switch($action) { + case 'retrieving the element': + try { + $world['result'] = $world['provider']->{$arguments[0]}; + } catch (Exception $e) { + $world['result'] = $e; + } + break; + default: + return $this->notImplemented($action); + } + } + + /** + * Handle a "then" step. + * + * @param array &$world Joined "world" of variables. + * @param string $action The description of the step. + * @param array $arguments Additional arguments to the step. + * + * @return mixed The outcome of the step. + */ + public function runThen(&$world, $action, $arguments) + { + switch($action) { + case 'the result is': + $this->assertEquals($arguments[0], $world['result']); + break; + case 'the result is an error': + $this->assertTrue($world['result'] instanceOf Exception); + break; + case 'the result is an error with the message': + $this->assertTrue($world['result'] instanceOf Exception); + $this->assertEquals($arguments[0], $world['result']->getMessage()); + break; + default: + return $this->notImplemented($action); + } + } +} diff --git a/framework/Provider/test/Horde/Provider/ProviderTest.php b/framework/Provider/test/Horde/Provider/ProviderTest.php new file mode 100644 index 000000000..4dd7c2671 --- /dev/null +++ b/framework/Provider/test/Horde/Provider/ProviderTest.php @@ -0,0 +1,195 @@ + + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ + +/** + * Load the basic story testing class. + */ +require_once 'ProviderScenario.php'; + +/** + * Test the Horde_Provider class. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you + * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html. + * + * @category Horde + * @package Provider + * @subpackage UnitTests + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Horde_Provider_ProviderTest extends Horde_Provider_ProviderScenario +{ + /** + * Test retrieving an unset element. + * + * @scenario + * + * @return NULL + */ + public function retrievingAnUnsetElementYieldsAnError() + { + $this->given('a provider') + ->when('retrieving the element', 'key') + ->then('the result is an error with the message', + 'No such element: key'); + } + + /** + * Test retrieving a simple element. + * + * @scenario + * + * @return NULL + */ + public function retrievingASimpleElement() + { + $this->given('a provider') + ->given('a registered element', 'key', 'value') + ->when('retrieving the element', 'key') + ->then('the result is', 'value'); + } + + /** + * Test retrieving a new element with invalid recursion. + * + * @scenario + * + * @return NULL + */ + public function retrievingARecursingElement() + { + $injection = new Horde_Provider_Injection_Factory(array('Recursion', + 'getValue')); + + $this->given('a provider') + ->given('a registered element', 'recursion', $injection) + ->when('retrieving the element', 'recursion') + ->then('the result is an error with the message', + 'Element already loading!'); + } + + /** + * Test retrieving a new element via a factory function. + * + * @scenario + * + * @return NULL + */ + public function retrievingANewElementWithAFactoryFunction() + { + $injection = new Horde_Provider_Injection_Factory('factory'); + + $this->given('a provider') + ->given('a registered element', 'key', $injection) + ->when('retrieving the element', 'key') + ->then('the result is', 'injected'); + } + + /** + * Test retrieving a new element via a factory class method. + * + * @scenario + * + * @return NULL + */ + public function retrievingANewElementWithAFactoryClassMethod() + { + $injection = new Horde_Provider_Injection_Factory(array('Dummy', + 'getValue')); + + $this->given('a provider') + ->given('a registered element', 'key', $injection) + ->when('retrieving the element', 'key') + ->then('the result is', 'constructed'); + } + +} + +/** + * A dummy factory. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you + * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html. + * + * @category Horde + * @package Provider + * @subpackage UnitTests + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Dummy +{ + /** + * A factory method producing a constant string. + * + * @param Horde_Provider $provider The dependency provider. + * + * @return string Always returns 'constructed' + */ + static public function getValue($provider) + { + return 'constructed'; + } +} + +/** + * A dummy factory used to demonstrate recursion. + * + * Copyright 2009 The Horde Project (http://www.horde.org/) + * + * See the enclosed file COPYING for license information (LGPL). If you + * did not receive this file, see http://www.fsf.org/copyleft/lgpl.html. + * + * @category Horde + * @package Provider + * @subpackage UnitTests + * @author Gunnar Wrobel + * @license http://www.fsf.org/copyleft/lgpl.html LGPL + * @link http://pear.horde.org/index.php?package=Provider + */ +class Recursion +{ + /** + * A factory method that returns the provided 'recursion' element. + * + * @param Horde_Provider $provider The dependency provider. + * + * @return mixed The element 'recursion' from the provider. + */ + static public function getValue($provider) + { + //@todo: Why does $provider->recursion yield no error/result? + //return $provider->recursion; + return $provider->__get('recursion'); + } +} + +/** + * A factory producing a constant string. + * + * @param Horde_Provider $provider The dependency provider. + * + * @return string Always returns 'injected' + */ +function factory($provider) +{ + return 'injected'; +} -- 2.11.0