diff --git a/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php b/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
index a4e8b9449..f8e188906 100644
--- a/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
+++ b/tests/Composer/Test/Autoload/AutoloadGeneratorTest.php
@@ -15,26 +15,25 @@ namespace Composer\Test\Installer;
 use Composer\Autoload\AutoloadGenerator;
 use Composer\Util\Filesystem;
 use Composer\Package\MemoryPackage;
+use Composer\Test\TestCase;
 
-class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
+class AutoloadGeneratorTest extends TestCase
 {
     public $vendorDir;
     private $workingDir;
     private $im;
     private $repository;
     private $generator;
+    private $fs;
 
     protected function setUp()
     {
-        $fs = new Filesystem;
+        $this->fs = new Filesystem;
         $that = $this;
 
         $this->workingDir = realpath(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);
+        $this->ensureDirectoryExistsAndClear($this->vendorDir);
 
         $this->dir = getcwd();
         chdir($this->workingDir);
@@ -53,13 +52,20 @@ class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
                 return $that->vendorDir;
             }));
 
-        $this->repo = $this->getMock('Composer\Repository\RepositoryInterface');
+        $this->repository = $this->getMock('Composer\Repository\RepositoryInterface');
 
         $this->generator = new AutoloadGenerator();
     }
 
     protected function tearDown()
     {
+        if ($this->vendorDir === $this->workingDir) {
+            if (is_dir($this->workingDir.'/.composer')) {
+                $this->fs->removeDirectory($this->workingDir.'/.composer');
+            }
+        } elseif (is_dir($this->vendorDir)) {
+            $this->fs->removeDirectory($this->vendorDir);
+        }
         chdir($this->dir);
     }
 
@@ -68,12 +74,12 @@ class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
         $package = new MemoryPackage('a', '1.0', '1.0');
         $package->setAutoload(array('psr-0' => array('Main' => 'src/', 'Lala' => 'src/')));
 
-        $this->repo->expects($this->once())
+        $this->repository->expects($this->once())
             ->method('getPackages')
             ->will($this->returnValue(array()));
 
         mkdir($this->vendorDir.'/.composer');
-        $this->generator->dump($this->repo, $package, $this->im, $this->vendorDir.'/.composer');
+        $this->generator->dump($this->repository, $package, $this->im, $this->vendorDir.'/.composer');
         $this->assertAutoloadFiles('main', $this->vendorDir.'/.composer');
     }
 
@@ -84,14 +90,15 @@ class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
         $package = new MemoryPackage('a', '1.0', '1.0');
         $package->setAutoload(array('psr-0' => array('Main' => 'src/', 'Lala' => 'src/')));
 
-        $this->repo->expects($this->once())
+        $this->repository->expects($this->once())
             ->method('getPackages')
             ->will($this->returnValue(array()));
 
         if (!is_dir($this->vendorDir.'/.composer')) {
             mkdir($this->vendorDir.'/.composer', 0777, true);
         }
-        $this->generator->dump($this->repo, $package, $this->im, $this->vendorDir.'/.composer');
+
+        $this->generator->dump($this->repository, $package, $this->im, $this->vendorDir.'/.composer');
         $this->assertAutoloadFiles('main3', $this->vendorDir.'/.composer');
     }
 
@@ -100,13 +107,13 @@ class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
         $package = new MemoryPackage('a', '1.0', '1.0');
         $package->setAutoload(array('psr-0' => array('Main' => 'src/', 'Lala' => 'src/')));
 
-        $this->repo->expects($this->once())
+        $this->repository->expects($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');
+        $this->generator->dump($this->repository, $package, $this->im, $this->vendorDir.'/.composer');
         $this->assertAutoloadFiles('main2', $this->vendorDir.'/.composer');
     }
 
@@ -120,12 +127,12 @@ class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
         $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())
+        $this->repository->expects($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');
+        $this->generator->dump($this->repository, $package, $this->im, $this->vendorDir.'/.composer');
         $this->assertAutoloadFiles('vendors', $this->vendorDir.'/.composer');
     }
 
@@ -140,12 +147,12 @@ class AutoloadGeneratorTest extends \PHPUnit_Framework_TestCase
         $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())
+        $this->repository->expects($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');
+        $this->generator->dump($this->repository, $package, $this->im, $this->vendorDir.'/.composer');
         $this->assertAutoloadFiles('override_vendors', $this->vendorDir.'/.composer');
     }
 
diff --git a/tests/Composer/Test/Installer/LibraryInstallerTest.php b/tests/Composer/Test/Installer/LibraryInstallerTest.php
index ba86954e3..b89bf9b9a 100644
--- a/tests/Composer/Test/Installer/LibraryInstallerTest.php
+++ b/tests/Composer/Test/Installer/LibraryInstallerTest.php
@@ -15,8 +15,9 @@ namespace Composer\Test\Installer;
 use Composer\Installer\LibraryInstaller;
 use Composer\DependencyResolver\Operation;
 use Composer\Util\Filesystem;
+use Composer\Test\TestCase;
 
-class LibraryInstallerTest extends \PHPUnit_Framework_TestCase
+class LibraryInstallerTest extends TestCase
 {
     private $vendorDir;
     private $binDir;
@@ -30,16 +31,10 @@ class LibraryInstallerTest extends \PHPUnit_Framework_TestCase
         $this->fs = new Filesystem;
 
         $this->vendorDir = realpath(sys_get_temp_dir()).DIRECTORY_SEPARATOR.'composer-test-vendor';
-        if (is_dir($this->vendorDir)) {
-            $this->fs->removeDirectory($this->vendorDir);
-        }
-        mkdir($this->vendorDir);
+        $this->ensureDirectoryExistsAndClear($this->vendorDir);
 
         $this->binDir = realpath(sys_get_temp_dir()).DIRECTORY_SEPARATOR.'composer-test-bin';
-        if (is_dir($this->binDir)) {
-            $this->fs->removeDirectory($this->binDir);
-        }
-        mkdir($this->binDir);
+        $this->ensureDirectoryExistsAndClear($this->binDir);
 
         $this->dm = $this->getMockBuilder('Composer\Downloader\DownloadManager')
             ->disableOriginalConstructor()
@@ -52,6 +47,17 @@ class LibraryInstallerTest extends \PHPUnit_Framework_TestCase
             ->getMock();
     }
 
+    protected function tearDown()
+    {
+        if (is_dir($this->vendorDir)) {
+            $this->fs->removeDirectory($this->vendorDir);
+        }
+
+        if (is_dir($this->binDir)) {
+            $this->fs->removeDirectory($this->binDir);
+        }
+    }
+
     public function testInstallerCreationShouldNotCreateVendorDirectory()
     {
         $this->fs->removeDirectory($this->vendorDir);
diff --git a/tests/Composer/Test/TestCase.php b/tests/Composer/Test/TestCase.php
index 1e3ae257e..f0c8ab8fd 100644
--- a/tests/Composer/Test/TestCase.php
+++ b/tests/Composer/Test/TestCase.php
@@ -15,6 +15,7 @@ namespace Composer\Test;
 use Composer\Package\Version\VersionParser;
 use Composer\Package\MemoryPackage;
 use Composer\Package\LinkConstraint\VersionConstraint;
+use Composer\Util\Filesystem;
 
 abstract class TestCase extends \PHPUnit_Framework_TestCase
 {
@@ -40,4 +41,13 @@ abstract class TestCase extends \PHPUnit_Framework_TestCase
         $normVersion = self::$versionParser->normalize($version);
         return new MemoryPackage($name, $normVersion, $version);
     }
+
+    protected function ensureDirectoryExistsAndClear($directory)
+    {
+        $fs = new Filesystem();
+        if (is_dir($directory)) {
+            $fs->removeDirectory($directory);
+        }
+        mkdir($directory, 0777, true);
+    }
 }