Fixing #1220. This should also resolve the old JoomlaCode tracker item:

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=25337

libraries/joomla/filesystem/path.php

@@ -200,9 +200,14 @@ public static function clean($path, $ds = DIRECTORY_SEPARATOR)
 		{
 			$path = JPATH_ROOT;
 		}
+		// Remove double slashes and backslashes and convert all slashes and backslashes to DIRECTORY_SEPARATOR
+		// If dealing with a UNC path don't forget to prepend the path with a backslash.
+		elseif (($ds == '\\') && ($path[0] == '\\' ) && ( $path[1] == '\\' ))
+		{
+			$path = "\\" . preg_replace('#[/\\\\]+#', $ds, $path);
+		}
 		else
 		{
-			// Remove double slashes and backslashes and convert all slashes and backslashes to DIRECTORY_SEPARATOR
 			$path = preg_replace('#[/\\\\]+#', $ds, $path);
 		}
 

tests/suites/unit/joomla/filesystem/JPathTest.php

@@ -1,110 +1,112 @@
 <?php
 /**
  * @package     Joomla.UnitTest
+ * @subpackage  Filesystem
  *
- * @copyright   Copyright (C) 2005 - 2012 Open Source Matters, Inc. All rights reserved.
+ * @copyright   Copyright (C) 2005 - 2011 Open Source Matters, Inc. All rights reserved.
  * @license     GNU General Public License version 2 or later; see LICENSE
  */
 
-include_once JPATH_PLATFORM . '/joomla/filesystem/path.php';
+JLoader::register('JPath', JPATH_PLATFORM . '/joomla/filesystem/path.php');
 
 /**
- * Test class for JPath.
- * Generated by PHPUnit on 2011-10-26 at 19:32:34.
+ * Tests for the JPath class.
+ *
+ * @package     Joomla.UnitTest
+ * @subpackage  Filesystem
+ * @since       12.2
  */
-class JPathTest extends PHPUnit_Framework_TestCase {
-
-    /**
-     * @var JPath
-     */
-    protected $object;
-
-    /**
-     * Sets up the fixture, for example, opens a network connection.
-     * This method is called before a test is executed.
-     */
-    protected function setUp() {
-        $this->object = new JPath;
-    }
+class JPathTest extends TestCase
+{
+	/**
+	 * Data provider for testClean() method.
+	 *
+	 * @return  array
+	 *
+	 * @since   12.2
+	 */
+	public function getCleanData()
+	{
+		return array(
+			// Input Path, Directory Separator, Expected Output
+			'Nothing to do.' => array('/var/www/foo/bar/baz', '/', '/var/www/foo/bar/baz'),
+			'One backslash.' => array('/var/www/foo\\bar/baz', '/', '/var/www/foo/bar/baz'),
+			'Two and one backslashes.' => array('/var/www\\\\foo\\bar/baz', '/', '/var/www/foo/bar/baz'),
+			'Mixed backslashes and double forward slashes.' => array('/var\\/www//foo\\bar/baz', '/', '/var/www/foo/bar/baz'),
+			'UNC path.' => array('\\\\www\\docroot', '\\', '\\\\www\\docroot'),
+			'UNC path with forward slash.' => array('\\\\www/docroot', '\\', '\\\\www\\docroot'),
+			'UNC path with UNIX directory separator.' => array('\\\\www/docroot', '/', '/www/docroot'),
+		);
+	}
 
-    /**
-     * Tears down the fixture, for example, closes a network connection.
-     * This method is called after a test is executed.
-     */
-    protected function tearDown() {
-
-    }
-
-    /**
+	/**
      * @todo Implement testCanChmod().
      */
-    public function testCanChmod() {
-        // Remove the following lines when you implement this test.
-        $this->markTestIncomplete(
-                'This test has not been implemented yet.'
-        );
-    }
+	public function testCanChmod()
+	{
+		// Remove the following lines when you implement this test.
+		$this->markTestIncomplete('This test has not been implemented yet.');
+	}
 
-    /**
+	/**
      * @todo Implement testSetPermissions().
      */
-    public function testSetPermissions() {
-        // Remove the following lines when you implement this test.
-        $this->markTestIncomplete(
-                'This test has not been implemented yet.'
-        );
-    }
+	public function testSetPermissions()
+	{
+		// Remove the following lines when you implement this test.
+		$this->markTestIncomplete('This test has not been implemented yet.');
+	}
 
-    /**
+	/**
      * @todo Implement testGetPermissions().
      */
-    public function testGetPermissions() {
-        // Remove the following lines when you implement this test.
-        $this->markTestIncomplete(
-                'This test has not been implemented yet.'
-        );
-    }
+	public function testGetPermissions()
+	{
+		// Remove the following lines when you implement this test.
+		$this->markTestIncomplete('This test has not been implemented yet.');
+	}
 
-    /**
+	/**
      * @todo Implement testCheck().
      */
-    public function testCheck() {
-        // Remove the following lines when you implement this test.
-        $this->markTestIncomplete(
-                'This test has not been implemented yet.'
-        );
-    }
+	public function testCheck()
+	{
+		// Remove the following lines when you implement this test.
+		$this->markTestIncomplete('This test has not been implemented yet.');
+	}
 
-    /**
-     * @todo Implement testClean().
-     */
-    public function testClean() {
-        // Remove the following lines when you implement this test.
-        $this->markTestIncomplete(
-                'This test has not been implemented yet.'
-        );
-    }
+	/**
+	 * Tests the clean method.
+	 *
+	 * @return  void
+	 *
+	 * @covers        JPath::clean
+	 * @dataProvider  getCleanData
+	 * @since         12.2
+	 */
+	public function testClean($input, $ds, $expected)
+	{
+		$this->assertEquals(
+			$expected,
+			JPath::clean($input, $ds)
+		);
+	}
 
-    /**
+	/**
      * @todo Implement testIsOwner().
      */
-    public function testIsOwner() {
-        // Remove the following lines when you implement this test.
-        $this->markTestIncomplete(
-                'This test has not been implemented yet.'
-        );
-    }
+	public function testIsOwner()
+	{
+		// Remove the following lines when you implement this test.
+		$this->markTestIncomplete('This test has not been implemented yet.');
+	}
 
-    /**
+	/**
      * @todo Implement testFind().
      */
-    public function testFind() {
-        // Remove the following lines when you implement this test.
-        $this->markTestIncomplete(
-                'This test has not been implemented yet.'
-        );
-    }
-
+	public function testFind()
+	{
+		// Remove the following lines when you implement this test.
+		$this->markTestIncomplete('This test has not been implemented yet.');
+	}
 }
-
-?>