Make StandaloneExtensionManagers configurable

doc/book/reader.md

@@ -532,9 +532,9 @@ manager". Extension managers must implement `Zend\Feed\Reader\ExtensionManagerIn
 Three implementations exist:
 
 - `Zend\Feed\Reader\StandaloneExtensionManager` is a hard-coded implementation
-  seeded with all feed and entry implementations. You can extend it to add
-  extensions, though it's likely easier to copy and paste it, adding your
-  changes.
+  seeded with all feed and entry implementations. You can add simple extensions
+  from it using `add` and `remove` methods. `ExtensionPluginManager` is
+  recommended for more complex needs.
 - `Zend\Feed\Reader\ExtensionPluginManager` is a `Zend\ServiceManager\AbstractPluginManager`
   implementation, `Zend\Feed\Reader\ExtensionManager`; as such, you can extend
   it to add more extensions, use a `Zend\ServiceManager\ConfigInterface` instance
@@ -727,7 +727,8 @@ your extension manager knows about it, and then register the extension with
 
 The following example uses `Zend\Feed\Reader\ExtensionPluginManager` to manage
 extensions, as it provides the ability to register new extensions without
-requiring extension of the plugin manager itself. To use it, first intall
+requiring extension of the plugin manager itself (note that this example works
+with ServiceManager v2, but not v3). To use it, first install
 zend-servicemanager:
 
 ```bash

src/Reader/StandaloneExtensionManager.php

@@ -9,22 +9,24 @@
 
 namespace Zend\Feed\Reader;
 
+use Zend\Feed\Reader\Exception\InvalidArgumentException;
+
 class StandaloneExtensionManager implements ExtensionManagerInterface
 {
     private $extensions = [
-        'Atom\Entry'            => 'Zend\Feed\Reader\Extension\Atom\Entry',
-        'Atom\Feed'             => 'Zend\Feed\Reader\Extension\Atom\Feed',
-        'Content\Entry'         => 'Zend\Feed\Reader\Extension\Content\Entry',
-        'CreativeCommons\Entry' => 'Zend\Feed\Reader\Extension\CreativeCommons\Entry',
-        'CreativeCommons\Feed'  => 'Zend\Feed\Reader\Extension\CreativeCommons\Feed',
-        'DublinCore\Entry'      => 'Zend\Feed\Reader\Extension\DublinCore\Entry',
-        'DublinCore\Feed'       => 'Zend\Feed\Reader\Extension\DublinCore\Feed',
-        'Podcast\Entry'         => 'Zend\Feed\Reader\Extension\Podcast\Entry',
-        'Podcast\Feed'          => 'Zend\Feed\Reader\Extension\Podcast\Feed',
-        'Slash\Entry'           => 'Zend\Feed\Reader\Extension\Slash\Entry',
-        'Syndication\Feed'      => 'Zend\Feed\Reader\Extension\Syndication\Feed',
-        'Thread\Entry'          => 'Zend\Feed\Reader\Extension\Thread\Entry',
-        'WellFormedWeb\Entry'   => 'Zend\Feed\Reader\Extension\WellFormedWeb\Entry',
+        'Atom\Entry'            => Extension\Atom\Entry::class,
+        'Atom\Feed'             => Extension\Atom\Feed::class,
+        'Content\Entry'         => Extension\Content\Entry::class,
+        'CreativeCommons\Entry' => Extension\CreativeCommons\Entry::class,
+        'CreativeCommons\Feed'  => Extension\CreativeCommons\Feed::class,
+        'DublinCore\Entry'      => Extension\DublinCore\Entry::class,
+        'DublinCore\Feed'       => Extension\DublinCore\Feed::class,
+        'Podcast\Entry'         => Extension\Podcast\Entry::class,
+        'Podcast\Feed'          => Extension\Podcast\Feed::class,
+        'Slash\Entry'           => Extension\Slash\Entry::class,
+        'Syndication\Feed'      => Extension\Syndication\Feed::class,
+        'Thread\Entry'          => Extension\Thread\Entry::class,
+        'WellFormedWeb\Entry'   => Extension\WellFormedWeb\Entry::class,
     ];
 
     /**
@@ -49,4 +51,38 @@ public function get($extension)
         $class = $this->extensions[$extension];
         return new $class();
     }
+
+    /**
+     * Add an extension.
+     *
+     * @param string $name
+     * @param string $class
+     */
+    public function add($name, $class)
+    {
+        if (is_string($class) && (
+            is_a($class, Extension\AbstractEntry::class, true) ||
+            is_a($class, Extension\AbstractFeed::class, true))
+        ) {
+            $this->extensions[$name] = $class;
+            return;
+        }
+
+        throw new InvalidArgumentException(sprintf(
+            'Plugin of type %s is invalid; must implement %2$s\Extension\AbstractFeed '
+            . 'or %2$s\Extension\AbstractEntry',
+            $class,
+            __NAMESPACE__
+        ));
+    }
+
+    /**
+     * Remove an extension.
+     *
+     * @param string $name
+     */
+    public function remove($name)
+    {
+        unset($this->extensions[$name]);
+    }
 }

src/Writer/StandaloneExtensionManager.php

@@ -9,6 +9,8 @@
 
 namespace Zend\Feed\Writer;
 
+use Zend\Feed\Writer\Exception\InvalidArgumentException;
+
 class StandaloneExtensionManager implements ExtensionManagerInterface
 {
     private $extensions = [
@@ -47,4 +49,40 @@ public function get($extension)
         $class = $this->extensions[$extension];
         return new $class();
     }
+
+    /**
+     * Add an extension.
+     *
+     * @param string $name
+     * @param string $class
+     */
+    public function add($name, $class)
+    {
+        if (is_string($class) && ((
+            is_a($class, Extension\AbstractRenderer::class, true) ||
+            'Feed' === substr($class, -4) ||
+            'Entry' === substr($class, -5)
+        ))) {
+            $this->extensions[$name] = $class;
+
+            return;
+        }
+
+        throw new InvalidArgumentException(sprintf(
+            'Plugin of type %s is invalid; must implement %s\Extension\RendererInterface '
+            . 'or the classname must end in "Feed" or "Entry"',
+            $class,
+            __NAMESPACE__
+        ));
+    }
+
+    /**
+     * Remove an extension.
+     *
+     * @param string $name
+     */
+    public function remove($name)
+    {
+        unset($this->extensions[$name]);
+    }
 }

test/Reader/StandaloneExtensionManagerTest.php

@@ -16,6 +16,11 @@
 
 class StandaloneExtensionManagerTest extends TestCase
 {
+    /**
+     * @var StandaloneExtensionManager
+     */
+    private $extensions;
+
     public function setUp()
     {
         $this->extensions = new StandaloneExtensionManager();
@@ -80,4 +85,29 @@ public function testEachPluginRetrievalReturnsNewInstance($pluginName, $pluginCl
         $this->assertInstanceOf($pluginClass, $test);
         $this->assertNotSame($extension, $test);
     }
+
+    public function testAddAcceptsValidExtensionClasses()
+    {
+        $ext = $this->createMock(\Zend\Feed\Reader\Extension\AbstractEntry::class);
+        $this->extensions->add('Test/Entry', get_class($ext));
+        $this->assertTrue($this->extensions->has('Test/Entry'));
+        $ext = $this->createMock(\Zend\Feed\Reader\Extension\AbstractFeed::class);
+        $this->extensions->add('Test/Feed', get_class($ext));
+        $this->assertTrue($this->extensions->has('Test/Feed'));
+    }
+
+    public function testAddRejectsInvalidExtensions()
+    {
+        $this->expectException(\Zend\Feed\Reader\Exception\InvalidArgumentException::class);
+        $this->extensions->add('Test/Entry', 'blah');
+    }
+
+    public function testExtensionRemoval()
+    {
+        $ext = $this->createMock(\Zend\Feed\Reader\Extension\AbstractEntry::class);
+        $this->extensions->add('Test/Entry', get_class($ext));
+        $this->assertTrue($this->extensions->has('Test/Entry'));
+        $this->extensions->remove('Test/Entry');
+        $this->assertFalse($this->extensions->has('Test/Entry'));
+    }
 }

test/Writer/StandaloneExtensionManagerTest.php

@@ -0,0 +1,123 @@
+<?php
+/**
+ * Zend Framework (http://framework.zend.com/)
+ *
+ * @link      http://github.com/zendframework/zf2 for the canonical source repository
+ * @copyright Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ */
+namespace ZendTest\Feed\Writer;
+
+use PHPUnit\Framework\TestCase;
+use Zend\Feed\Writer\StandaloneExtensionManager;
+use Zend\Feed\Writer\ExtensionManagerInterface;
+
+class StandaloneExtensionManagerTest extends TestCase
+{
+    /**
+     * @var StandaloneExtensionManager
+     */
+    private $extensions;
+
+    public function setUp()
+    {
+        $this->extensions = new StandaloneExtensionManager();
+    }
+
+    public function testIsAnExtensionManagerImplementation()
+    {
+        $this->assertInstanceOf(ExtensionManagerInterface::class, $this->extensions);
+    }
+
+    public function defaultPlugins()
+    {
+        return [
+            'Atom\Renderer\Feed'           => [
+                'Atom\Renderer\Feed', \Zend\Feed\Writer\Extension\Atom\Renderer\Feed::class
+            ],
+            'Content\Renderer\Entry'       => [
+                'Content\Renderer\Entry', \Zend\Feed\Writer\Extension\Content\Renderer\Entry::class
+            ],
+            'DublinCore\Renderer\Entry'    => [
+                'DublinCore\Renderer\Entry', \Zend\Feed\Writer\Extension\DublinCore\Renderer\Entry::class
+            ],
+            'DublinCore\Renderer\Feed'     => [
+                'DublinCore\Renderer\Feed', \Zend\Feed\Writer\Extension\DublinCore\Renderer\Feed::class
+            ],
+            'ITunes\Entry'                 => ['ITunes\Entry', \Zend\Feed\Writer\Extension\ITunes\Entry::class],
+            'ITunes\Feed'                  => ['ITunes\Feed', \Zend\Feed\Writer\Extension\ITunes\Feed::class],
+            'ITunes\Renderer\Entry'        => [
+                'ITunes\Renderer\Entry', \Zend\Feed\Writer\Extension\ITunes\Renderer\Entry::class
+            ],
+            'ITunes\Renderer\Feed'         => [
+                'ITunes\Renderer\Feed', \Zend\Feed\Writer\Extension\ITunes\Renderer\Feed::class
+            ],
+            'Slash\Renderer\Entry'         => [
+                'Slash\Renderer\Entry', \Zend\Feed\Writer\Extension\Slash\Renderer\Entry::class
+            ],
+            'Threading\Renderer\Entry'     => [
+                'Threading\Renderer\Entry', \Zend\Feed\Writer\Extension\Threading\Renderer\Entry::class
+            ],
+            'WellFormedWeb\Renderer\Entry' => [
+                'WellFormedWeb\Renderer\Entry', \Zend\Feed\Writer\Extension\WellFormedWeb\Renderer\Entry::class
+            ],
+        ];
+    }
+
+    /**
+     * @dataProvider defaultPlugins
+     */
+    public function testHasAllDefaultPlugins($pluginName, $pluginClass)
+    {
+        $this->assertTrue($this->extensions->has($pluginName));
+    }
+
+    /**
+     * @dataProvider defaultPlugins
+     */
+    public function testCanRetrieveDefaultPluginInstances($pluginName, $pluginClass)
+    {
+        $extension = $this->extensions->get($pluginName);
+        $this->assertInstanceOf($pluginClass, $extension);
+    }
+
+    /**
+     * @dataProvider defaultPlugins
+     */
+    public function testEachPluginRetrievalReturnsNewInstance($pluginName, $pluginClass)
+    {
+        $extension = $this->extensions->get($pluginName);
+        $this->assertInstanceOf($pluginClass, $extension);
+
+        $test = $this->extensions->get($pluginName);
+        $this->assertInstanceOf($pluginClass, $test);
+        $this->assertNotSame($extension, $test);
+    }
+
+    public function testAddAcceptsValidExtensionClasses()
+    {
+        $this->extensions->add('Test/Feed', 'MyTestExtension_Feed');
+        $this->assertTrue($this->extensions->has('Test/Feed'));
+
+        $this->extensions->add('Test/Entry', 'MyTestExtension_Entry');
+        $this->assertTrue($this->extensions->has('Test/Entry'));
+
+        $ext = $this->createMock(\Zend\Feed\Writer\Extension\AbstractRenderer::class);
+        $this->extensions->add('Test/Thing', get_class($ext));
+        $this->assertTrue($this->extensions->has('Test/Thing'));
+    }
+
+    public function testAddRejectsInvalidExtensions()
+    {
+        $this->expectException(\Zend\Feed\Writer\Exception\InvalidArgumentException::class);
+        $this->extensions->add('Test/Feed', 'blah');
+    }
+
+    public function testExtensionRemoval()
+    {
+        $this->extensions->add('Test/Entry', 'MyTestExtension_Entry');
+        $this->assertTrue($this->extensions->has('Test/Entry'));
+        $this->extensions->remove('Test/Entry');
+        $this->assertFalse($this->extensions->has('Test/Entry'));
+    }
+}