diff --git a/src/Composer/Installer.php b/src/Composer/Installer.php
index 4ef8ea848..933d563e7 100644
--- a/src/Composer/Installer.php
+++ b/src/Composer/Installer.php
@@ -27,6 +27,7 @@ use Composer\Package\Link;
 use Composer\Package\LinkConstraint\VersionConstraint;
 use Composer\Package\Locker;
 use Composer\Package\PackageInterface;
+use Composer\Repository\ArrayRepository;
 use Composer\Repository\CompositeRepository;
 use Composer\Repository\PlatformRepository;
 use Composer\Repository\RepositoryInterface;
@@ -76,6 +77,11 @@ class Installer
      */
     protected $eventDispatcher;
 
+    /**
+     * @var AutoloadGenerator
+     */
+    protected $autoloadGenerator;
+
     protected $preferSource = false;
     protected $devMode = false;
     protected $dryRun = false;
@@ -102,8 +108,9 @@ class Installer
      * @param Locker $locker
      * @param InstallationManager $installationManager
      * @param EventDispatcher $eventDispatcher
+     * @param AutoloadGenerator $autoloadGenerator
      */
-    public function __construct(IOInterface $io, PackageInterface $package, DownloadManager $downloadManager, RepositoryManager $repositoryManager, Locker $locker, InstallationManager $installationManager, EventDispatcher $eventDispatcher)
+    public function __construct(IOInterface $io, PackageInterface $package, DownloadManager $downloadManager, RepositoryManager $repositoryManager, Locker $locker, InstallationManager $installationManager, EventDispatcher $eventDispatcher, autoloadGenerator $autoloadGenerator)
     {
         $this->io = $io;
         $this->package = $package;
@@ -112,6 +119,7 @@ class Installer
         $this->locker = $locker;
         $this->installationManager = $installationManager;
         $this->eventDispatcher = $eventDispatcher;
+        $this->autoloadGenerator = $autoloadGenerator;
     }
 
     /**
@@ -128,7 +136,13 @@ class Installer
         }
 
         // create installed repo, this contains all local packages + platform packages (php & extensions)
-        $repos = array_merge($this->repositoryManager->getLocalRepositories(), array(new PlatformRepository()));
+        $repos = array_merge(
+            $this->repositoryManager->getLocalRepositories(),
+            array(
+                new ArrayRepository(array($this->package)),
+                new PlatformRepository(),
+            )
+        );
         $installedRepo = new CompositeRepository($repos);
         if ($this->additionalInstalledRepository) {
             $installedRepo->addRepository($this->additionalInstalledRepository);
@@ -172,9 +186,8 @@ class Installer
 
             // write autoloader
             $this->io->write('<info>Generating autoload files</info>');
-            $generator = new AutoloadGenerator;
             $localRepos = new CompositeRepository($this->repositoryManager->getLocalRepositories());
-            $generator->dump($localRepos, $this->package, $this->installationManager, $this->installationManager->getVendorPath() . '/composer', true);
+            $this->autoloadGenerator->dump($localRepos, $this->package, $this->installationManager, $this->installationManager->getVendorPath() . '/composer', true);
 
             // dispatch post event
             $eventName = $this->update ? ScriptEvents::POST_UPDATE_CMD : ScriptEvents::POST_INSTALL_CMD;
@@ -201,6 +214,10 @@ class Installer
         // creating requirements request
         $installFromLock = false;
         $request = new Request($pool);
+
+        $constraint = new VersionConstraint('=', $this->package->getVersion());
+        $request->install($this->package->getName(), $constraint);
+
         if ($this->update) {
             $this->io->write('<info>Updating '.($devMode ? 'dev ': '').'dependencies</info>');
 
@@ -406,11 +423,13 @@ class Installer
      * @param IOInterface $io
      * @param Composer $composer
      * @param EventDispatcher $eventDispatcher
+     * @param AutoloadGenerator $autoloadGenerator
      * @return Installer
      */
-    static public function create(IOInterface $io, Composer $composer, EventDispatcher $eventDispatcher = null)
+    static public function create(IOInterface $io, Composer $composer, EventDispatcher $eventDispatcher = null, AutoloadGenerator $autoloadGenerator = null)
     {
         $eventDispatcher = $eventDispatcher ?: new EventDispatcher($composer, $io);
+        $autoloadGenerator = $autoloadGenerator ?: new AutoloadGenerator;
 
         return new static(
             $io,
@@ -419,7 +438,8 @@ class Installer
             $composer->getRepositoryManager(),
             $composer->getLocker(),
             $composer->getInstallationManager(),
-            $eventDispatcher
+            $eventDispatcher,
+            $autoloadGenerator
         );
     }
 
diff --git a/src/Composer/Installer/InstallationManager.php b/src/Composer/Installer/InstallationManager.php
index e5080e0ef..3bf09de4f 100644
--- a/src/Composer/Installer/InstallationManager.php
+++ b/src/Composer/Installer/InstallationManager.php
@@ -33,7 +33,7 @@ class InstallationManager
 {
     private $installers = array();
     private $cache = array();
-    private $vendorPath;
+    protected $vendorPath;
 
     /**
      * Creates an instance of InstallationManager
@@ -204,7 +204,7 @@ class InstallationManager
         }
     }
 
-    private function antiAlias(PackageInterface $package)
+    protected function antiAlias(PackageInterface $package)
     {
         if ($package instanceof AliasPackage) {
             $alias = $package;
diff --git a/src/Composer/Repository/ArrayRepository.php b/src/Composer/Repository/ArrayRepository.php
index 1af73d311..7a6336393 100644
--- a/src/Composer/Repository/ArrayRepository.php
+++ b/src/Composer/Repository/ArrayRepository.php
@@ -25,6 +25,13 @@ class ArrayRepository implements RepositoryInterface
 {
     protected $packages;
 
+    public function __construct(array $packages = array())
+    {
+        foreach ($packages as $package) {
+            $this->addPackage($package);
+        }
+    }
+
     /**
      * {@inheritDoc}
      */
diff --git a/tests/Composer/Test/InstallerTest.php b/tests/Composer/Test/InstallerTest.php
new file mode 100644
index 000000000..179d0fe47
--- /dev/null
+++ b/tests/Composer/Test/InstallerTest.php
@@ -0,0 +1,115 @@
+<?php
+/*
+ * This file is part of Composer.
+ *
+ * (c) Nils Adermann <naderman@naderman.de>
+ *     Jordi Boggiano <j.boggiano@seld.be>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Composer\Test;
+
+use Composer\Installer;
+use Composer\Repository\ArrayRepository;
+use Composer\Repository\RepositoryManager;
+use Composer\Repository\RepositoryInterface;
+use Composer\Package\PackageInterface;
+use Composer\Package\Link;
+use Composer\Test\Mock\WritableRepositoryMock;
+use Composer\Test\Mock\InstallationManagerMock;
+
+class InstallerTest extends TestCase
+{
+    /**
+     * @dataProvider provideInstaller
+     */
+    public function testInstaller(array $expectedInstalled, array $expectedUpdated, array $expectedUninstalled, PackageInterface $package, RepositoryInterface $repository)
+    {
+        $io = $this->getMock('Composer\IO\IOInterface');
+
+        $package = $this->getPackage('A', '1.0.0');
+        $package->setRequires(array(
+            new Link('A', 'B', $this->getVersionConstraint('=', '1.0.0')),
+        ));
+
+        $downloadManager = $this->getMock('Composer\Downloader\DownloadManager');
+        $config = $this->getMock('Composer\Config');
+
+        $repositoryManager = new RepositoryManager($io, $config);
+        $repositoryManager->setLocalRepository(new WritableRepositoryMock());
+        $repositoryManager->setLocalDevRepository(new WritableRepositoryMock());
+        $repositoryManager->addRepository($repository);
+
+        $locker = $this->getMockBuilder('Composer\Package\Locker')->disableOriginalConstructor()->getMock();
+        $installationManager = new InstallationManagerMock();
+        $eventDispatcher = $this->getMockBuilder('Composer\Script\EventDispatcher')->disableOriginalConstructor()->getMock();
+        $autoloadGenerator = $this->getMock('Composer\Autoload\AutoloadGenerator');
+
+        $installer = new Installer($io, $package, $downloadManager, $repositoryManager, $locker, $installationManager, $eventDispatcher, $autoloadGenerator);
+        $result = $installer->run();
+        $this->assertTrue($result);
+
+        $installed = $installationManager->getInstalledPackages();
+        $this->assertSame($expectedInstalled, array_map(array($this, 'getPackageString'), $installed));
+
+        $updated = $installationManager->getUpdatedPackages();
+        $this->assertSame($expectedUpdated, array_map(array($this, 'getPackageString'), $updated));
+
+        $uninstalled = $installationManager->getUninstalledPackages();
+        $this->assertSame($expectedUninstalled, array_map(array($this, 'getPackageString'), $uninstalled));
+    }
+
+    public function provideInstaller()
+    {
+        $cases = array();
+
+        // when A requires B and B requires A, and A is a non-published root package
+        // the install of B should succeed
+
+        $a = $this->getPackage('A', '1.0.0');
+        $a->setRequires(array(
+            new Link('A', 'B', $this->getVersionConstraint('=', '1.0.0')),
+        ));
+        $b = $this->getPackage('B', '1.0.0');
+        $b->setRequires(array(
+            new Link('B', 'A', $this->getVersionConstraint('=', '1.0.0')),
+        ));
+
+        $cases[] = array(
+            array('b-1.0.0.0'),
+            array(),
+            array(),
+            $a,
+            new ArrayRepository(array($b)),
+        );
+
+        // #480: when A requires B and B requires A, and A is a published root package
+        // only B should be installed, as A is the root
+
+        $a = $this->getPackage('A', '1.0.0');
+        $a->setRequires(array(
+            new Link('A', 'B', $this->getVersionConstraint('=', '1.0.0')),
+        ));
+        $b = $this->getPackage('B', '1.0.0');
+        $b->setRequires(array(
+            new Link('B', 'A', $this->getVersionConstraint('=', '1.0.0')),
+        ));
+
+        $cases[] = array(
+            array('b-1.0.0.0'),
+            array(),
+            array(),
+            $a,
+            new ArrayRepository(array($a, $b)),
+        );
+
+        return $cases;
+    }
+
+    public function getPackageString(PackageInterface $package)
+    {
+        return (string) $package;
+    }
+}
diff --git a/tests/Composer/Test/Mock/InstallationManagerMock.php b/tests/Composer/Test/Mock/InstallationManagerMock.php
new file mode 100644
index 000000000..8f0f83008
--- /dev/null
+++ b/tests/Composer/Test/Mock/InstallationManagerMock.php
@@ -0,0 +1,65 @@
+<?php
+/*
+ * This file is part of Composer.
+ *
+ * (c) Nils Adermann <naderman@naderman.de>
+ *     Jordi Boggiano <j.boggiano@seld.be>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Composer\Test\Mock;
+
+use Composer\Installer\InstallationManager;
+use Composer\Repository\RepositoryInterface;
+use Composer\DependencyResolver\Operation\OperationInterface;
+use Composer\DependencyResolver\Operation\InstallOperation;
+use Composer\DependencyResolver\Operation\UpdateOperation;
+use Composer\DependencyResolver\Operation\UninstallOperation;
+
+class InstallationManagerMock extends InstallationManager
+{
+    private $installed = array();
+    private $updated = array();
+    private $uninstalled = array();
+
+    public function __construct($vendorDir = 'vendor')
+    {
+        $this->vendorPath = $vendorDir;
+    }
+
+    public function install(RepositoryInterface $repo, InstallOperation $operation)
+    {
+        $package = $this->antiAlias($operation->getPackage());
+        $this->installed[] = $package;
+    }
+
+    public function update(RepositoryInterface $repo, UpdateOperation $operation)
+    {
+        $initial = $this->antiAlias($operation->getInitialPackage());
+        $target = $this->antiAlias($operation->getTargetPackage());
+        $this->updated[] = $target;
+    }
+
+    public function uninstall(RepositoryInterface $repo, UninstallOperation $operation)
+    {
+        $package = $this->antiAlias($operation->getPackage());
+        $this->uninstalled[] = $package;
+    }
+
+    public function getInstalledPackages()
+    {
+        return $this->installed;
+    }
+
+    public function getUpdatedPackages()
+    {
+        return $this->updated;
+    }
+
+    public function getUninstalledPackages()
+    {
+        return $this->uninstalled;
+    }
+}
diff --git a/tests/Composer/Test/Mock/WritableRepositoryMock.php b/tests/Composer/Test/Mock/WritableRepositoryMock.php
new file mode 100644
index 000000000..59bb19f88
--- /dev/null
+++ b/tests/Composer/Test/Mock/WritableRepositoryMock.php
@@ -0,0 +1,26 @@
+<?php
+/*
+ * This file is part of Composer.
+ *
+ * (c) Nils Adermann <naderman@naderman.de>
+ *     Jordi Boggiano <j.boggiano@seld.be>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Composer\Test\Mock;
+
+use Composer\Repository\ArrayRepository;
+use Composer\Repository\WritableRepositoryInterface;
+
+class WritableRepositoryMock extends ArrayRepository implements WritableRepositoryInterface
+{
+    public function reload()
+    {
+    }
+
+    public function write()
+    {
+    }
+}
diff --git a/tests/Composer/Test/TestCase.php b/tests/Composer/Test/TestCase.php
index f0c8ab8fd..b2c2cc9cd 100644
--- a/tests/Composer/Test/TestCase.php
+++ b/tests/Composer/Test/TestCase.php
@@ -19,26 +19,19 @@ use Composer\Util\Filesystem;
 
 abstract class TestCase extends \PHPUnit_Framework_TestCase
 {
-    private static $versionParser;
-
-    public static function setUpBeforeClass()
-    {
-        if (!self::$versionParser) {
-            self::$versionParser = new VersionParser();
-        }
-    }
-
     protected function getVersionConstraint($operator, $version)
     {
+        $versionParser = new VersionParser();
         return new VersionConstraint(
             $operator,
-            self::$versionParser->normalize($version)
+            $versionParser->normalize($version)
         );
     }
 
     protected function getPackage($name, $version)
     {
-        $normVersion = self::$versionParser->normalize($version);
+        $versionParser = new VersionParser();
+        $normVersion = $versionParser->normalize($version);
         return new MemoryPackage($name, $normVersion, $version);
     }