diff --git a/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php b/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
new file mode 100644
index 000000000..f7b327092
--- /dev/null
+++ b/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
@@ -0,0 +1,120 @@
+<?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\Installer;
+
+use Composer\Autoload\AutoloadGenerator;
+use Composer\Downloader\Util\Filesystem;
+use Composer\Package\MemoryPackage;
+
+class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
+{
+    public $vendorDir;
+    private $workingDir;
+    private $im;
+    private $repository;
+    private $generator;
+
+    protected function setUp()
+    {
+        $fs = new Filesystem;
+        $that = $this;
+
+        $this->workingDir = sys_get_temp_dir();
+        $this->vendorDir = $this->workingDir.DIRECTORY_SEPARATOR.'composer-test-autoload';
+        if (is_dir($this->vendorDir)) {
+            $fs->removeDirectory($this->vendorDir);
+        }
+        mkdir($this->vendorDir);
+
+        $this->dir = getcwd();
+        chdir($this->workingDir);
+
+        $this->im = $this->getMockBuilder('Composer\Installer\InstallationManager')
+            ->disableOriginalConstructor()
+            ->getMock();
+        $this->im->expects($this->any())
+            ->method('getInstallPath')
+            ->will($this->returnCallback(function ($package) use ($that) {
+                return $that->vendorDir.'/'.$package->getName();
+            }));
+        $this->im->expects($this->any())
+            ->method('getVendorPath')
+            ->will($this->returnCallback(function () use ($that) {
+                return $that->vendorDir;
+            }));
+
+        $this->repo = $this->getMockBuilder('Composer\Repository\RepositoryInterface')
+            ->disableOriginalConstructor()
+            ->getMock();
+
+        $this->generator = new AutoloadGenerator();
+    }
+
+    protected function tearDown()
+    {
+        chdir($this->dir);
+    }
+
+    public function testMainPackageAutoloading()
+    {
+        $package = new MemoryPackage('a', '1.0', '1.0');
+        $package->setAutoload(array('psr-0' => array('Main' => 'src/', 'Lala' => 'src/')));
+
+        $this->repo->expects($this->once())
+            ->method('getPackages')
+            ->will($this->returnValue(array()));
+
+        mkdir($this->vendorDir.'/.composer');
+        $this->generator->dump($this->repo, $package, $this->im, $this->vendorDir.'/.composer');
+        $this->assertAutoloadFiles('main', $this->vendorDir.'/.composer');
+    }
+
+    public function testMainPackageAutoloadingAlternativeVendorDir()
+    {
+        $package = new MemoryPackage('a', '1.0', '1.0');
+        $package->setAutoload(array('psr-0' => array('Main' => 'src/', 'Lala' => 'src/')));
+
+        $this->repo->expects($this->once())
+            ->method('getPackages')
+            ->will($this->returnValue(array()));
+
+        $this->vendorDir .= '/subdir';
+        mkdir($this->vendorDir.'/.composer', 0777, true);
+        $this->generator->dump($this->repo, $package, $this->im, $this->vendorDir.'/.composer');
+        $this->assertAutoloadFiles('main2', $this->vendorDir.'/.composer');
+    }
+
+    public function testVendorsAutoloading()
+    {
+        $package = new MemoryPackage('a', '1.0', '1.0');
+
+        $packages = array();
+        $packages[] = $a = new MemoryPackage('a/a', '1.0', '1.0');
+        $packages[] = $b = new MemoryPackage('b/b', '1.0', '1.0');
+        $a->setAutoload(array('psr-0' => array('A' => 'src/', 'A\\B' => 'lib/')));
+        $b->setAutoload(array('psr-0' => array('B\\Sub\\Name' => 'src/')));
+
+        $this->repo->expects($this->once())
+            ->method('getPackages')
+            ->will($this->returnValue($packages));
+
+        mkdir($this->vendorDir.'/.composer', 0777, true);
+        $this->generator->dump($this->repo, $package, $this->im, $this->vendorDir.'/.composer');
+        $this->assertAutoloadFiles('vendors', $this->vendorDir.'/.composer');
+    }
+
+    private function assertAutoloadFiles($name, $dir)
+    {
+        $this->assertEquals(file_get_contents(__DIR__.'/Fixtures/autoload_'.$name.'.php'), file_get_contents($dir.'/autoload_namespaces.php'));
+    }
+}
diff --git a/tests/Composer/Test/Autoload/Fixtures/autoload_main.php b/tests/Composer/Test/Autoload/Fixtures/autoload_main.php
new file mode 100644
index 000000000..157d888f3
--- /dev/null
+++ b/tests/Composer/Test/Autoload/Fixtures/autoload_main.php
@@ -0,0 +1,10 @@
+<?php
+
+// autoload_namespace.php generated by Composer
+
+$vendorDir = dirname(__DIR__);
+
+return array(
+    'Main' => dirname($vendorDir) . '/src/',
+    'Lala' => dirname($vendorDir) . '/src/',
+);
diff --git a/tests/Composer/Test/Autoload/Fixtures/autoload_main2.php b/tests/Composer/Test/Autoload/Fixtures/autoload_main2.php
new file mode 100644
index 000000000..a0fa2c7db
--- /dev/null
+++ b/tests/Composer/Test/Autoload/Fixtures/autoload_main2.php
@@ -0,0 +1,10 @@
+<?php
+
+// autoload_namespace.php generated by Composer
+
+$vendorDir = dirname(__DIR__);
+
+return array(
+    'Main' => dirname(dirname($vendorDir)) . '/src/',
+    'Lala' => dirname(dirname($vendorDir)) . '/src/',
+);
diff --git a/tests/Composer/Test/Autoload/Fixtures/autoload_vendors.php b/tests/Composer/Test/Autoload/Fixtures/autoload_vendors.php
new file mode 100644
index 000000000..b149046df
--- /dev/null
+++ b/tests/Composer/Test/Autoload/Fixtures/autoload_vendors.php
@@ -0,0 +1,11 @@
+<?php
+
+// autoload_namespace.php generated by Composer
+
+$vendorDir = dirname(__DIR__);
+
+return array(
+    'B\\Sub\\Name' => $vendorDir . '/b/b/src/',
+    'A\\B' => $vendorDir . '/a/a/lib/',
+    'A' => $vendorDir . '/a/a/src/',
+);