Detect automatically the available asset manager

Asset/AbstractAssetManager.php

@@ -85,6 +85,16 @@ public function __construct(
         $this->fallback = $fallback;
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function isAvailable()
+    {
+        $this->executor->execute($this->getVersionCommand(), $version);
+
+        return '' !== trim($version);
+    }
+
     /**
      * {@inheritdoc}
      */

Asset/AssetManagerFinder.php

@@ -0,0 +1,95 @@
+<?php
+
+/*
+ * This file is part of the Foxy package.
+ *
+ * (c) François Pluchino <francois.pluchino@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Foxy\Asset;
+
+use Foxy\Exception\RuntimeException;
+
+/**
+ * Asset Manager finder.
+ *
+ * @author François Pluchino <francois.pluchino@gmail.com>
+ */
+class AssetManagerFinder
+{
+    /**
+     * @var AssetManagerInterface[]
+     */
+    private $managers;
+
+    /**
+     * Constructor.
+     *
+     * @param AssetManagerInterface[] $managers The asset managers
+     */
+    public function __construct(array $managers = array())
+    {
+        foreach ($managers as $manager) {
+            if ($manager instanceof AssetManagerInterface) {
+                $this->addManager($manager);
+            }
+        }
+    }
+
+    public function addManager(AssetManagerInterface $manager)
+    {
+        $this->managers[$manager->getName()] = $manager;
+    }
+
+    /**
+     * Find the asset manager.
+     *
+     * @param null|string $manager The name of the asset manager
+     *
+     * @throws RuntimeException When the asset manager does not exist
+     * @throws RuntimeException When the asset manager is not found
+     *
+     * @return AssetManagerInterface
+     */
+    public function findManager($manager = null)
+    {
+        if (null !== $manager) {
+            if (isset($this->managers[$manager])) {
+                return $this->managers[$manager];
+            }
+
+            throw new RuntimeException(sprintf('The asset manager "%s" doesn\'t exist', $manager));
+        }
+
+        return $this->findAvailableManager();
+    }
+
+    /**
+     * Find the available asset manager.
+     *
+     * @throws RuntimeException When no asset manager is found
+     *
+     * @return AssetManagerInterface
+     */
+    private function findAvailableManager()
+    {
+        // find asset manager by lockfile
+        foreach ($this->managers as $manager) {
+            if ($manager->hasLockFile()) {
+                return $manager;
+            }
+        }
+
+        // find asset manager by availability
+        foreach ($this->managers as $manager) {
+            if ($manager->isAvailable()) {
+                return $manager;
+            }
+        }
+
+        throw new RuntimeException('No asset manager is found');
+    }
+}

Asset/AssetManagerInterface.php

@@ -29,6 +29,13 @@ interface AssetManagerInterface
      */
     public function getName();
 
+    /**
+     * Check if the asset manager is available.
+     *
+     * @return bool
+     */
+    public function isAvailable();
+
     /**
      * Get the filename of the asset package.
      *

Foxy.php

@@ -22,6 +22,7 @@
 use Composer\Script\ScriptEvents;
 use Composer\Util\Filesystem;
 use Composer\Util\ProcessExecutor;
+use Foxy\Asset\AssetManagerFinder;
 use Foxy\Asset\AssetManagerInterface;
 use Foxy\Config\Config;
 use Foxy\Config\ConfigBuilder;
@@ -76,16 +77,16 @@ class Foxy implements PluginInterface, EventSubscriberInterface
      * The list of the classes of asset managers.
      */
     private static $assetManagers = array(
-        'Foxy\Asset\NpmManager',
         'Foxy\Asset\YarnManager',
+        'Foxy\Asset\NpmManager',
     );
 
     /**
      * The default values of config.
      */
     private static $defaultConfig = array(
         'enabled' => true,
-        'manager' => 'npm',
+        'manager' => null,
         'manager-version' => array(
             'npm' => '>=5.0.0',
             'yarn' => '>=1.0.0',
@@ -218,16 +219,12 @@ public function solveAssets(Event $event)
      */
     protected function getAssetManager(IOInterface $io, Config $config, ProcessExecutor $executor, Filesystem $fs)
     {
-        $manager = $config->get('manager');
+        $amf = new AssetManagerFinder();
 
         foreach (self::$assetManagers as $class) {
-            $am = new $class($io, $config, $executor, $fs);
-
-            if ($am instanceof AssetManagerInterface && $manager === $am->getName()) {
-                return $am;
-            }
+            $amf->addManager(new $class($io, $config, $executor, $fs));
         }
 
-        throw new RuntimeException(sprintf('The asset manager "%s" doesn\'t exist', $manager));
+        return $amf->findManager($config->get('manager'));
     }
 }

Tests/Asset/AssetManagerFinderTest.php

@@ -0,0 +1,133 @@
+<?php
+
+/*
+ * This file is part of the Foxy package.
+ *
+ * (c) François Pluchino <francois.pluchino@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Foxy\Tests\Asset;
+
+use Foxy\Asset\AssetManagerFinder;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Asset manager finder tests.
+ *
+ * @author François Pluchino <francois.pluchino@gmail.com>
+ *
+ * @internal
+ */
+final class AssetManagerFinderTest extends TestCase
+{
+    public function testFindManagerWithValidManager()
+    {
+        $am = $this->getMockBuilder('Foxy\Asset\AssetManagerInterface')->getMock();
+
+        $am->expects(static::once())
+            ->method('getName')
+            ->willReturn('foo')
+        ;
+
+        $amf = new AssetManagerFinder(array($am));
+        $res = $amf->findManager('foo');
+
+        static::assertSame($am, $res);
+    }
+
+    /**
+     * @expectedException \Foxy\Exception\RuntimeException
+     * @expectedExceptionMessage The asset manager "bar" doesn't exist
+     */
+    public function testFindManagerWithInvalidManager()
+    {
+        $am = $this->getMockBuilder('Foxy\Asset\AssetManagerInterface')->getMock();
+
+        $am->expects(static::once())
+            ->method('getName')
+            ->willReturn('foo')
+        ;
+
+        $amf = new AssetManagerFinder(array($am));
+        $amf->findManager('bar');
+    }
+
+    public function testFindManagerWithAutoManagerAndAvailableManagerByLockFile()
+    {
+        $am = $this->getMockBuilder('Foxy\Asset\AssetManagerInterface')->getMock();
+
+        $am->expects(static::once())
+            ->method('getName')
+            ->willReturn('foo')
+        ;
+
+        $am->expects(static::once())
+            ->method('hasLockFile')
+            ->willReturn(true)
+        ;
+
+        $am->expects(static::never())
+            ->method('isAvailable')
+        ;
+
+        $amf = new AssetManagerFinder(array($am));
+        $res = $amf->findManager(null);
+
+        static::assertSame($am, $res);
+    }
+
+    public function testFindManagerWithAutoManagerAndAvailableManagerByAvailability()
+    {
+        $am = $this->getMockBuilder('Foxy\Asset\AssetManagerInterface')->getMock();
+
+        $am->expects(static::once())
+            ->method('getName')
+            ->willReturn('foo')
+        ;
+
+        $am->expects(static::once())
+            ->method('hasLockFile')
+            ->willReturn(false)
+        ;
+
+        $am->expects(static::once())
+            ->method('isAvailable')
+            ->willReturn(true)
+        ;
+
+        $amf = new AssetManagerFinder(array($am));
+        $res = $amf->findManager(null);
+
+        static::assertSame($am, $res);
+    }
+
+    /**
+     * @expectedException \Foxy\Exception\RuntimeException
+     * @expectedExceptionMessage No asset manager is found
+     */
+    public function testFindManagerWithAutoManagerAndNoAvailableManager()
+    {
+        $am = $this->getMockBuilder('Foxy\Asset\AssetManagerInterface')->getMock();
+
+        $am->expects(static::atLeastOnce())
+            ->method('getName')
+            ->willReturn('foo')
+        ;
+
+        $am->expects(static::once())
+            ->method('hasLockFile')
+            ->willReturn(false)
+        ;
+
+        $am->expects(static::once())
+            ->method('isAvailable')
+            ->willReturn(false)
+        ;
+
+        $amf = new AssetManagerFinder(array($am));
+        $amf->findManager(null);
+    }
+}