Integrated vfsStream better and made paths constants VFS-based

Signed-off-by: dchill42 <dchill42@gmail.com>
diff --git a/tests/mocks/core/common.php b/tests/mocks/core/common.php
index a655ee1..b001074 100644
--- a/tests/mocks/core/common.php
+++ b/tests/mocks/core/common.php
@@ -39,6 +39,30 @@
 	}
 }
 
+if ( ! function_exists('get_mimes'))
+{
+	/**
+	 * Returns the MIME types array from config/mimes.php
+	 *
+	 * @return	array
+	 */
+	function &get_mimes()
+	{
+		static $_mimes = array();
+
+		if (empty($_mimes))
+		{
+			$path = realpath(PROJECT_BASE.'application/config/mimes.php');
+			if (is_file($path))
+			{
+				$_mimes = include($path);
+			}
+		}
+
+		return $_mimes;
+	}
+}
+
 // --------------------------------------------------------------------
 
 if ( ! function_exists('load_class'))
@@ -166,4 +190,4 @@
 	{
 		return TRUE;
 	}
-}
\ No newline at end of file
+}
diff --git a/tests/mocks/core/loader.php b/tests/mocks/core/loader.php
index 9eb7825..7ea4da3 100644
--- a/tests/mocks/core/loader.php
+++ b/tests/mocks/core/loader.php
@@ -3,36 +3,6 @@
 class Mock_Core_Loader extends CI_Loader {
 
 	/**
-	 * Since we use paths to load up models, views, etc, we need the ability to
-	 * mock up the file system so when core tests are run, we aren't mucking
-	 * in the application directory. This will give finer grained control over
-	 * these tests. Also, by mocking the system directory, we eliminate dependency
-	 * on any other classes so errors in libraries, helpers, etc. don't give false
-	 * negatives for the actual loading process. So yeah, while this looks odd,
-	 * I need to overwrite protected class vars in the loader. So here we go...
-	 *
-	 * @covers CI_Loader::__construct()
-	 */
-	public function __construct()
-	{
-		// Create VFS tree of loader locations
-		$this->root = vfsStream::setup();
-		$this->app_root = vfsStream::newDirectory('application')->at($this->root);
-		$this->base_root = vfsStream::newDirectory('system')->at($this->root);
-
-		// Get VFS app and base path URLs
-		$this->app_path = vfsStream::url('application').'/';
-		$this->base_path = vfsStream::url('system').'/';
-
-		// Set loader paths with VFS URLs
-		$this->_ci_ob_level  		= ob_get_level();
-		$this->_ci_library_paths	= array($this->app_path, $this->base_path);
-		$this->_ci_helper_paths 	= array($this->app_path, $this->base_path);
-		$this->_ci_model_paths 		= array($this->app_path);
-		$this->_ci_view_paths 		= array($this->app_path.'views/' => TRUE);
-	}
-
-	/**
 	 * Give public access to _ci_autoloader for testing
 	 */
 	public function autoload()