diff --git a/phpBB/includes/acp/acp_extensions.php b/phpBB/includes/acp/acp_extensions.php
index c21c9f4e9d..2ff479d824 100644
--- a/phpBB/includes/acp/acp_extensions.php
+++ b/phpBB/includes/acp/acp_extensions.php
@@ -88,6 +88,11 @@ class acp_extensions
 			break;
 
 			case 'enable_pre':
+				if (!$md_manager->validate_dir())
+				{
+					trigger_error($user->lang['EXTENSION_DIR_INVALID'] . adm_back_link($this->u_action), E_USER_WARNING);
+				}
+
 				if (!$md_manager->validate_enable())
 				{
 					trigger_error($user->lang['EXTENSION_NOT_AVAILABLE'] . adm_back_link($this->u_action), E_USER_WARNING);
@@ -108,6 +113,11 @@ class acp_extensions
 			break;
 
 			case 'enable':
+				if (!$md_manager->validate_dir())
+				{
+					trigger_error($user->lang['EXTENSION_DIR_INVALID'] . adm_back_link($this->u_action), E_USER_WARNING);
+				}
+
 				if (!$md_manager->validate_enable())
 				{
 					trigger_error($user->lang['EXTENSION_NOT_AVAILABLE'] . adm_back_link($this->u_action), E_USER_WARNING);
diff --git a/phpBB/language/en/acp/extensions.php b/phpBB/language/en/acp/extensions.php
index 8279a68022..67b34ff0c7 100644
--- a/phpBB/language/en/acp/extensions.php
+++ b/phpBB/language/en/acp/extensions.php
@@ -41,6 +41,7 @@ $lang = array_merge($lang, array(
 	'EXTENSIONS_EXPLAIN'		=> 'The Extensions Manager is a tool in your phpBB Board which allows you to manage all of your extensions statuses and view information about them.',
 	'EXTENSION_INVALID_LIST'	=> 'The “%s” extension is not valid.<br />%s<br /><br />',
 	'EXTENSION_NOT_AVAILABLE'	=> 'The selected extension is not available for this board, please verify your phpBB and PHP versions are allowed (see the details page).',
+	'EXTENSION_DIR_INVALID'		=> 'The selected extension has an invalid directory structure and cannot be enabled.',
 
 	'DETAILS'				=> 'Details',
 
diff --git a/phpBB/phpbb/extension/manager.php b/phpBB/phpbb/extension/manager.php
index 7f009867c9..23b281deaa 100644
--- a/phpBB/phpbb/extension/manager.php
+++ b/phpBB/phpbb/extension/manager.php
@@ -411,9 +411,24 @@ class manager
 			if ($file_info->isFile() && $file_info->getFilename() == 'ext.' . $this->php_ext)
 			{
 				$ext_name = $iterator->getInnerIterator()->getSubPath();
+				$composer_file = $iterator->getPath() . '/composer.json';
 
+				// Ignore the extension if there is no composer.json.
+				if (!is_readable($composer_file) || !($ext_info = file_get_contents($composer_file)))
+				{
+					continue;
+				}
+
+				$ext_info = json_decode($ext_info, true);
 				$ext_name = str_replace(DIRECTORY_SEPARATOR, '/', $ext_name);
 
+				// Ignore the extension if directory depth is not correct or if the directory structure
+				// does not match the name value specified in composer.json.
+				if (substr_count($ext_name, '/') !== 1 || !isset($ext_info['name']) || $ext_name != $ext_info['name'])
+				{
+					continue;
+				}
+
 				$available[$ext_name] = $this->phpbb_root_path . 'ext/' . $ext_name . '/';
 			}
 		}
diff --git a/phpBB/phpbb/extension/metadata_manager.php b/phpBB/phpbb/extension/metadata_manager.php
index d0323120d8..66cdb86513 100644
--- a/phpBB/phpbb/extension/metadata_manager.php
+++ b/phpBB/phpbb/extension/metadata_manager.php
@@ -266,8 +266,8 @@ class metadata_manager
 	 */
 	public function validate_enable()
 	{
-		// Check for phpBB, PHP versions
-		if (!$this->validate_require_phpbb() || !$this->validate_require_php())
+		// Check for valid directory & phpBB, PHP versions
+		if (!$this->validate_dir() || !$this->validate_require_phpbb() || !$this->validate_require_php())
 		{
 			return false;
 		}
@@ -275,6 +275,16 @@ class metadata_manager
 		return true;
 	}
 
+	/**
+	 * Validates the most basic directory structure to ensure it follows <vendor>/<ext> convention.
+	 *
+	 * @return boolean True when passes validation
+	 */
+	public function validate_dir()
+	{
+		return (substr_count($this->ext_name, '/') === 1 && $this->ext_name == $this->get_metadata('name'));
+	}
+
 
 	/**
 	 * Validates the contents of the phpbb requirement field
diff --git a/tests/extension/ext/barfoo/composer.json b/tests/extension/ext/barfoo/composer.json
new file mode 100644
index 0000000000..35d5d2a956
--- /dev/null
+++ b/tests/extension/ext/barfoo/composer.json
@@ -0,0 +1,22 @@
+{
+	"name": "vendor/barfoo",
+	"type": "phpbb-extension",
+	"description": "An example/sample extension to be used for testing purposes in phpBB Development.",
+	"version": "1.0.0",
+	"time": "2012-02-15 01:01:01",
+	"licence": "GNU GPL v2",
+	"authors": [{
+			"name": "John Smith",
+			"username": "JohnSmith27",
+			"email": "email@phpbb.com",
+			"homepage": "http://phpbb.com",
+			"role": "N/A"
+		}],
+	"require": {
+		"php": ">=5.3",
+		"phpbb/phpbb": "3.1.*@dev"
+	},
+	"extra": {
+		"display-name": "phpBB BarFoo Extension"
+	}
+}
diff --git a/tests/extension/ext/barfoo/ext.php b/tests/extension/ext/barfoo/ext.php
index 1b7bb7ca5e..0de403424c 100644
--- a/tests/extension/ext/barfoo/ext.php
+++ b/tests/extension/ext/barfoo/ext.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace barfoo;
+namespace vendor\barfoo;
 
 class ext extends \phpbb\extension\base
 {
diff --git a/tests/extension/ext/vendor/moo/composer.json b/tests/extension/ext/vendor/moo/composer.json
index 4dc36963b3..901cb7f17a 100644
--- a/tests/extension/ext/vendor/moo/composer.json
+++ b/tests/extension/ext/vendor/moo/composer.json
@@ -1,5 +1,5 @@
 {
-	"name": "moo/example",
+	"name": "vendor/moo",
 	"type": "phpbb-extension",
 	"description": "An example/sample extension to be used for testing purposes in phpBB Development.",
 	"version": "1.0.0",
diff --git a/tests/extension/ext/barfoo/acp/a_info.php b/tests/extension/ext/vendor2/bar/acp/a_info.php
similarity index 69%
rename from tests/extension/ext/barfoo/acp/a_info.php
rename to tests/extension/ext/vendor2/bar/acp/a_info.php
index ea07189f7a..8132df587f 100644
--- a/tests/extension/ext/barfoo/acp/a_info.php
+++ b/tests/extension/ext/vendor2/bar/acp/a_info.php
@@ -1,14 +1,14 @@
 <?php
 
-namespace barfoo\acp;
+namespace vendor2\bar\acp;
 
 class a_info
 {
 	public function module()
 	{
 		return array(
-			'filename'	=> 'barfoo\\acp\\a_module',
-			'title'		=> 'Barfoo',
+			'filename'	=> 'vendor2\\bar\\acp\\a_module',
+			'title'		=> 'Bar',
 			'version'	=> '3.1.0-dev',
 			'modes'		=> array(
 				'config'		=> array('title' => 'Config',	'auth' => '', 'cat' => array('ACP_MODS')),
diff --git a/tests/extension/ext/foo/mcp/a_module.php b/tests/extension/ext/vendor2/bar/acp/a_module.php
similarity index 50%
rename from tests/extension/ext/foo/mcp/a_module.php
rename to tests/extension/ext/vendor2/bar/acp/a_module.php
index ca397e7004..3a3d105790 100644
--- a/tests/extension/ext/foo/mcp/a_module.php
+++ b/tests/extension/ext/vendor2/bar/acp/a_module.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace foo\mcp;
+namespace vendor2\bar\acp;
 
 class a_module
 {
diff --git a/tests/extension/ext/vendor2/bar/composer.json b/tests/extension/ext/vendor2/bar/composer.json
new file mode 100644
index 0000000000..5d60ec031e
--- /dev/null
+++ b/tests/extension/ext/vendor2/bar/composer.json
@@ -0,0 +1,21 @@
+{
+	"name": "vendor2/bar",
+	"type": "phpbb-extension",
+	"description": "An example/sample extension to be used for testing purposes in phpBB Development.",
+	"version": "1.0.0",
+	"time": "2012-02-15 01:01:01",
+	"licence": "GPL-2.0",
+	"authors": [{
+			"name": "John Smith",
+			"email": "email@phpbb.com",
+			"homepage": "http://phpbb.com",
+			"role": "N/A"
+		}],
+	"require": {
+		"php": ">=5.3",
+		"phpbb/phpbb": "3.1.*@dev"
+	},
+	"extra": {
+		"display-name": "phpBB Bar Extension"
+	}
+}
diff --git a/tests/extension/ext/bar/ext.php b/tests/extension/ext/vendor2/bar/ext.php
similarity index 93%
rename from tests/extension/ext/bar/ext.php
rename to tests/extension/ext/vendor2/bar/ext.php
index 22ff5e8077..f94ab9ad81 100644
--- a/tests/extension/ext/bar/ext.php
+++ b/tests/extension/ext/vendor2/bar/ext.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace bar;
+namespace vendor2\bar;
 
 class ext extends \phpbb\extension\base
 {
diff --git a/tests/extension/ext/foo/a_class.php b/tests/extension/ext/vendor2/foo/a_class.php
similarity index 53%
rename from tests/extension/ext/foo/a_class.php
rename to tests/extension/ext/vendor2/foo/a_class.php
index 9db45a697f..06278c0e0c 100644
--- a/tests/extension/ext/foo/a_class.php
+++ b/tests/extension/ext/vendor2/foo/a_class.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace foo;
+namespace vendor2\foo;
 
 class a_class
 {
diff --git a/tests/extension/ext/foo/acp/a_info.php b/tests/extension/ext/vendor2/foo/acp/a_info.php
similarity index 76%
rename from tests/extension/ext/foo/acp/a_info.php
rename to tests/extension/ext/vendor2/foo/acp/a_info.php
index 3b7d8cdd42..27e67c1556 100644
--- a/tests/extension/ext/foo/acp/a_info.php
+++ b/tests/extension/ext/vendor2/foo/acp/a_info.php
@@ -1,13 +1,13 @@
 <?php
 
-namespace foo\acp;
+namespace vendor2\foo\acp;
 
 class a_info
 {
 	public function module()
 	{
 		return array(
-			'filename'	=> 'foo\\acp\\a_module',
+			'filename'	=> 'vendor2\\foo\\acp\\a_module',
 			'title'		=> 'Foobar',
 			'version'	=> '3.1.0-dev',
 			'modes'		=> array(
diff --git a/tests/extension/ext/foo/acp/a_module.php b/tests/extension/ext/vendor2/foo/acp/a_module.php
similarity index 50%
rename from tests/extension/ext/foo/acp/a_module.php
rename to tests/extension/ext/vendor2/foo/acp/a_module.php
index 7aa2351ab3..78d91af2fe 100644
--- a/tests/extension/ext/foo/acp/a_module.php
+++ b/tests/extension/ext/vendor2/foo/acp/a_module.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace foo\acp;
+namespace vendor2\foo\acp;
 
 class a_module
 {
diff --git a/tests/extension/ext/foo/acp/fail_info.php b/tests/extension/ext/vendor2/foo/acp/fail_info.php
similarity index 83%
rename from tests/extension/ext/foo/acp/fail_info.php
rename to tests/extension/ext/vendor2/foo/acp/fail_info.php
index 01d29fc5eb..d9b4353957 100644
--- a/tests/extension/ext/foo/acp/fail_info.php
+++ b/tests/extension/ext/vendor2/foo/acp/fail_info.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace foo\acp;
+namespace vendor2\foo\acp;
 
 /*
 * Due to the mismatch between the class name and the file name, this module
@@ -11,7 +11,7 @@ class foo_info
 	public function module()
 	{
 		return array(
-			'filename'	=> 'foo\acp\fail_module',
+			'filename'	=> 'vendor2\foo\acp\fail_module',
 			'title'		=> 'Foobar',
 			'version'	=> '3.1.0-dev',
 			'modes'		=> array(
diff --git a/tests/extension/ext/foo/acp/fail_module.php b/tests/extension/ext/vendor2/foo/acp/fail_module.php
similarity index 86%
rename from tests/extension/ext/foo/acp/fail_module.php
rename to tests/extension/ext/vendor2/foo/acp/fail_module.php
index 8070929d3c..c8a5eae745 100644
--- a/tests/extension/ext/foo/acp/fail_module.php
+++ b/tests/extension/ext/vendor2/foo/acp/fail_module.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace foo\acp;
+namespace vendor2\foo\acp;
 
 /*
 * Due to the mismatch between the class name and the file name of the module
diff --git a/tests/extension/ext/foo/b_class.php b/tests/extension/ext/vendor2/foo/b_class.php
similarity index 53%
rename from tests/extension/ext/foo/b_class.php
rename to tests/extension/ext/vendor2/foo/b_class.php
index bb2a77c05e..3d0f193908 100644
--- a/tests/extension/ext/foo/b_class.php
+++ b/tests/extension/ext/vendor2/foo/b_class.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace foo;
+namespace vendor2\foo;
 
 class b_class
 {
diff --git a/tests/extension/ext/foo/composer.json b/tests/extension/ext/vendor2/foo/composer.json
similarity index 95%
rename from tests/extension/ext/foo/composer.json
rename to tests/extension/ext/vendor2/foo/composer.json
index 5367eaf593..8821d9d50e 100644
--- a/tests/extension/ext/foo/composer.json
+++ b/tests/extension/ext/vendor2/foo/composer.json
@@ -1,5 +1,5 @@
 {
-	"name": "foo/example",
+	"name": "vendor2/foo",
 	"type": "phpbb-extension",
 	"description": "An example/sample extension to be used for testing purposes in phpBB Development.",
 	"version": "1.0.0",
diff --git a/tests/extension/ext/foo/ext.php b/tests/extension/ext/vendor2/foo/ext.php
similarity index 88%
rename from tests/extension/ext/foo/ext.php
rename to tests/extension/ext/vendor2/foo/ext.php
index ac6098f2f1..15480fe92a 100644
--- a/tests/extension/ext/foo/ext.php
+++ b/tests/extension/ext/vendor2/foo/ext.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace foo;
+namespace vendor2\foo;
 
 class ext extends \phpbb\extension\base
 {
diff --git a/tests/extension/ext/foo/mcp/a_info.php b/tests/extension/ext/vendor2/foo/mcp/a_info.php
similarity index 76%
rename from tests/extension/ext/foo/mcp/a_info.php
rename to tests/extension/ext/vendor2/foo/mcp/a_info.php
index 9a896ce808..b5599fde65 100644
--- a/tests/extension/ext/foo/mcp/a_info.php
+++ b/tests/extension/ext/vendor2/foo/mcp/a_info.php
@@ -1,13 +1,13 @@
 <?php
 
-namespace foo\mcp;
+namespace vendor2\foo\mcp;
 
 class a_info
 {
 	public function module()
 	{
 		return array(
-			'filename'	=> 'foo\\mcp\\a_module',
+			'filename'	=> 'vendor2\\foo\\mcp\\a_module',
 			'title'		=> 'Foobar',
 			'version'	=> '3.1.0-dev',
 			'modes'		=> array(
diff --git a/tests/extension/ext/barfoo/acp/a_module.php b/tests/extension/ext/vendor2/foo/mcp/a_module.php
similarity index 50%
rename from tests/extension/ext/barfoo/acp/a_module.php
rename to tests/extension/ext/vendor2/foo/mcp/a_module.php
index 0ae8775013..fe29783827 100644
--- a/tests/extension/ext/barfoo/acp/a_module.php
+++ b/tests/extension/ext/vendor2/foo/mcp/a_module.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace barfoo\acp;
+namespace vendor2\foo\mcp;
 
 class a_module
 {
diff --git a/tests/extension/ext/foo/sub/type/alternative.php b/tests/extension/ext/vendor2/foo/sub/type/alternative.php
similarity index 100%
rename from tests/extension/ext/foo/sub/type/alternative.php
rename to tests/extension/ext/vendor2/foo/sub/type/alternative.php
diff --git a/tests/extension/ext/foo/type/alternative.php b/tests/extension/ext/vendor2/foo/type/alternative.php
similarity index 100%
rename from tests/extension/ext/foo/type/alternative.php
rename to tests/extension/ext/vendor2/foo/type/alternative.php
diff --git a/tests/extension/ext/foo/type/dummy/empty.txt b/tests/extension/ext/vendor2/foo/type/dummy/empty.txt
similarity index 100%
rename from tests/extension/ext/foo/type/dummy/empty.txt
rename to tests/extension/ext/vendor2/foo/type/dummy/empty.txt
diff --git a/tests/extension/ext/foo/typewrong/error.php b/tests/extension/ext/vendor2/foo/typewrong/error.php
similarity index 100%
rename from tests/extension/ext/foo/typewrong/error.php
rename to tests/extension/ext/vendor2/foo/typewrong/error.php
diff --git a/tests/extension/ext/vendor3/bar/ext.php b/tests/extension/ext/vendor3/bar/ext.php
new file mode 100644
index 0000000000..37a5e92059
--- /dev/null
+++ b/tests/extension/ext/vendor3/bar/ext.php
@@ -0,0 +1,26 @@
+<?php
+
+namespace vendor3\bar;
+
+class ext extends \phpbb\extension\base
+{
+	static public $state;
+
+	public function enable_step($old_state)
+	{
+		// run 4 steps, then quit
+		if ($old_state === 4)
+		{
+			return false;
+		}
+
+		if ($old_state === false)
+		{
+			$old_state = 0;
+		}
+
+		self::$state = ++$old_state;
+
+		return self::$state;
+	}
+}
diff --git a/tests/extension/ext/bar/my/hidden_class.php b/tests/extension/ext/vendor3/bar/my/hidden_class.php
similarity index 54%
rename from tests/extension/ext/bar/my/hidden_class.php
rename to tests/extension/ext/vendor3/bar/my/hidden_class.php
index 504c1873dc..38eb59aadf 100644
--- a/tests/extension/ext/bar/my/hidden_class.php
+++ b/tests/extension/ext/vendor3/bar/my/hidden_class.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace bar\my;
+namespace vendor3\bar\my;
 
 class hidden_class
 {
diff --git a/tests/extension/ext/bar/styles/prosilver/template/foobar_body.html b/tests/extension/ext/vendor3/bar/styles/prosilver/template/foobar_body.html
similarity index 100%
rename from tests/extension/ext/bar/styles/prosilver/template/foobar_body.html
rename to tests/extension/ext/vendor3/bar/styles/prosilver/template/foobar_body.html
diff --git a/tests/extension/finder_test.php b/tests/extension/finder_test.php
index 8e6e71aaf8..d0ca5956b4 100644
--- a/tests/extension/finder_test.php
+++ b/tests/extension/finder_test.php
@@ -18,15 +18,15 @@ class phpbb_extension_finder_test extends phpbb_test_case
 		$this->extension_manager = new phpbb_mock_extension_manager(
 			dirname(__FILE__) . '/',
 			array(
-				'foo' => array(
-					'ext_name' => 'foo',
+				'vendor2/foo' => array(
+					'ext_name' => 'vendor2/foo',
 					'ext_active' => '1',
-					'ext_path' => 'ext/foo/',
+					'ext_path' => 'ext/vendor2/foo/',
 				),
-				'bar' => array(
-					'ext_name' => 'bar',
+				'vendor3/bar' => array(
+					'ext_name' => 'vendor3/bar',
 					'ext_active' => '1',
-					'ext_path' => 'ext/bar/',
+					'ext_path' => 'ext/vendor3/bar/',
 				),
 			));
 
@@ -43,10 +43,10 @@ class phpbb_extension_finder_test extends phpbb_test_case
 		sort($classes);
 		$this->assertEquals(
 			array(
-				'\bar\my\hidden_class',
-				'\foo\a_class',
-				'\foo\b_class',
 				'\phpbb\default\implementation',
+				'\vendor2\foo\a_class',
+				'\vendor2\foo\b_class',
+				'\vendor3\bar\my\hidden_class',
 			),
 			$classes
 		);
@@ -60,7 +60,7 @@ class phpbb_extension_finder_test extends phpbb_test_case
 
 		sort($dirs);
 		$this->assertEquals(array(
-			dirname(__FILE__) . '/ext/foo/type/',
+			dirname(__FILE__) . '/ext/vendor2/foo/type/',
 		), $dirs);
 	}
 
@@ -72,9 +72,9 @@ class phpbb_extension_finder_test extends phpbb_test_case
 
 		sort($dirs);
 		$this->assertEquals(array(
-			dirname(__FILE__) . '/ext/foo/sub/type/',
-			dirname(__FILE__) . '/ext/foo/type/',
-			dirname(__FILE__) . '/ext/foo/typewrong/',
+			dirname(__FILE__) . '/ext/vendor2/foo/sub/type/',
+			dirname(__FILE__) . '/ext/vendor2/foo/type/',
+			dirname(__FILE__) . '/ext/vendor2/foo/typewrong/',
 		), $dirs);
 	}
 
@@ -88,8 +88,8 @@ class phpbb_extension_finder_test extends phpbb_test_case
 		sort($classes);
 		$this->assertEquals(
 			array(
-				'\bar\my\hidden_class',
 				'\phpbb\default\implementation',
+				'\vendor3\bar\my\hidden_class',
 			),
 			$classes
 		);
@@ -105,9 +105,9 @@ class phpbb_extension_finder_test extends phpbb_test_case
 		sort($classes);
 		$this->assertEquals(
 			array(
-				'\foo\sub\type\alternative',
-				'\foo\type\alternative',
 				'\phpbb\default\implementation',
+				'\vendor2\foo\sub\type\alternative',
+				'\vendor2\foo\type\alternative',
 			),
 			$classes
 		);
@@ -122,7 +122,7 @@ class phpbb_extension_finder_test extends phpbb_test_case
 		sort($classes);
 		$this->assertEquals(
 			array(
-				'\foo\type\alternative',
+				'\vendor2\foo\type\alternative',
 			),
 			$classes
 		);
@@ -137,7 +137,7 @@ class phpbb_extension_finder_test extends phpbb_test_case
 		sort($classes);
 		$this->assertEquals(
 			array(
-				'\foo\sub\type\alternative',
+				'\vendor2\foo\sub\type\alternative',
 			),
 			$classes
 		);
@@ -152,7 +152,7 @@ class phpbb_extension_finder_test extends phpbb_test_case
 		sort($classes);
 		$this->assertEquals(
 			array(
-				'\foo\sub\type\alternative',
+				'\vendor2\foo\sub\type\alternative',
 			),
 			$classes
 		);
@@ -162,14 +162,14 @@ class phpbb_extension_finder_test extends phpbb_test_case
 	{
 		$files = $this->finder
 			->extension_directory('/type')
-			->find_from_extension('foo', dirname(__FILE__) . '/ext/foo/');
+			->find_from_extension('vendor2/foo', dirname(__FILE__) . '/ext/vendor2/foo/');
 		$classes = $this->finder->get_classes_from_files($files);
 
 		sort($classes);
 		$this->assertEquals(
 			array(
-				'\foo\type\alternative',
-				'\foo\type\dummy\empty',
+				'\vendor2\foo\type\alternative',
+				'\vendor2\foo\type\dummy\empty',
 			),
 			$classes
 		);
diff --git a/tests/extension/fixtures/extensions.xml b/tests/extension/fixtures/extensions.xml
index 6eb6fd11a5..6846162f0f 100644
--- a/tests/extension/fixtures/extensions.xml
+++ b/tests/extension/fixtures/extensions.xml
@@ -5,7 +5,7 @@
 		<column>ext_active</column>
 		<column>ext_state</column>
 		<row>
-			<value>foo</value>
+			<value>vendor2/foo</value>
 			<value>1</value>
 			<value></value>
 		</row>
diff --git a/tests/extension/manager_test.php b/tests/extension/manager_test.php
index b127daf2ed..cc32a6af4e 100644
--- a/tests/extension/manager_test.php
+++ b/tests/extension/manager_test.php
@@ -7,8 +7,8 @@
 *
 */
 
-require_once dirname(__FILE__) . '/ext/bar/ext.php';
-require_once dirname(__FILE__) . '/ext/foo/ext.php';
+require_once dirname(__FILE__) . '/ext/vendor2/bar/ext.php';
+require_once dirname(__FILE__) . '/ext/vendor2/foo/ext.php';
 require_once dirname(__FILE__) . '/ext/vendor/moo/ext.php';
 
 class phpbb_extension_manager_test extends phpbb_database_test_case
@@ -30,52 +30,53 @@ class phpbb_extension_manager_test extends phpbb_database_test_case
 
 	public function test_available()
 	{
-		$this->assertEquals(array('bar', 'barfoo', 'foo', 'vendor/moo'), array_keys($this->extension_manager->all_available()));
+		// barfoo and vendor3/bar should not listed due to missing composer.json. barfoo also has incorrect dir structure.
+		$this->assertEquals(array('vendor/moo', 'vendor2/bar', 'vendor2/foo'), array_keys($this->extension_manager->all_available()));
 	}
 
 	public function test_enabled()
 	{
-		$this->assertEquals(array('foo'), array_keys($this->extension_manager->all_enabled()));
+		$this->assertEquals(array('vendor2/foo'), array_keys($this->extension_manager->all_enabled()));
 	}
 
 	public function test_configured()
 	{
-		$this->assertEquals(array('foo', 'vendor/moo'), array_keys($this->extension_manager->all_configured()));
+		$this->assertEquals(array('vendor/moo', 'vendor2/foo'), array_keys($this->extension_manager->all_configured()));
 	}
 
 	public function test_enable()
 	{
-		bar\ext::$state = 0;
+		vendor2\bar\ext::$state = 0;
 
-		$this->assertEquals(array('foo'), array_keys($this->extension_manager->all_enabled()));
-		$this->extension_manager->enable('bar');
-		$this->assertEquals(array('bar', 'foo'), array_keys($this->extension_manager->all_enabled()));
-		$this->assertEquals(array('bar', 'foo', 'vendor/moo'), array_keys($this->extension_manager->all_configured()));
+		$this->assertEquals(array('vendor2/foo'), array_keys($this->extension_manager->all_enabled()));
+		$this->extension_manager->enable('vendor2/bar');
+		$this->assertEquals(array('vendor2/bar', 'vendor2/foo'), array_keys($this->extension_manager->all_enabled()));
+		$this->assertEquals(array('vendor/moo', 'vendor2/bar', 'vendor2/foo'), array_keys($this->extension_manager->all_configured()));
 
-		$this->assertEquals(4, bar\ext::$state);
+		$this->assertEquals(4, vendor2\bar\ext::$state);
 	}
 
 	public function test_disable()
 	{
-		foo\ext::$disabled = false;
+		vendor2\foo\ext::$disabled = false;
 
-		$this->assertEquals(array('foo'), array_keys($this->extension_manager->all_enabled()));
-		$this->extension_manager->disable('foo');
+		$this->assertEquals(array('vendor2/foo'), array_keys($this->extension_manager->all_enabled()));
+		$this->extension_manager->disable('vendor2/foo');
 		$this->assertEquals(array(), array_keys($this->extension_manager->all_enabled()));
-		$this->assertEquals(array('foo', 'vendor/moo'), array_keys($this->extension_manager->all_configured()));
+		$this->assertEquals(array('vendor/moo', 'vendor2/foo'), array_keys($this->extension_manager->all_configured()));
 
-		$this->assertTrue(foo\ext::$disabled);
+		$this->assertTrue(vendor2\foo\ext::$disabled);
 	}
 
 	public function test_purge()
 	{
 		vendor\moo\ext::$purged = false;
 
-		$this->assertEquals(array('foo'), array_keys($this->extension_manager->all_enabled()));
-		$this->assertEquals(array('foo', 'vendor/moo'), array_keys($this->extension_manager->all_configured()));
+		$this->assertEquals(array('vendor2/foo'), array_keys($this->extension_manager->all_enabled()));
+		$this->assertEquals(array('vendor/moo', 'vendor2/foo'), array_keys($this->extension_manager->all_configured()));
 		$this->extension_manager->purge('vendor/moo');
-		$this->assertEquals(array('foo'), array_keys($this->extension_manager->all_enabled()));
-		$this->assertEquals(array('foo'), array_keys($this->extension_manager->all_configured()));
+		$this->assertEquals(array('vendor2/foo'), array_keys($this->extension_manager->all_enabled()));
+		$this->assertEquals(array('vendor2/foo'), array_keys($this->extension_manager->all_configured()));
 
 		$this->assertTrue(vendor\moo\ext::$purged);
 	}
@@ -84,7 +85,7 @@ class phpbb_extension_manager_test extends phpbb_database_test_case
 	{
 		$extension_manager = $this->create_extension_manager(false);
 
-		$this->assertEquals(array('foo'), array_keys($extension_manager->all_enabled()));
+		$this->assertEquals(array('vendor2/foo'), array_keys($extension_manager->all_enabled()));
 	}
 
 	protected function create_extension_manager($with_cache = true)
diff --git a/tests/extension/metadata_manager_test.php b/tests/extension/metadata_manager_test.php
index 09eb83cd86..592421f9e7 100644
--- a/tests/extension/metadata_manager_test.php
+++ b/tests/extension/metadata_manager_test.php
@@ -82,7 +82,7 @@ class phpbb_extension_metadata_manager_test extends phpbb_database_test_case
 	// Should fail from missing composer.json
 	public function test_bar()
 	{
-		$ext_name = 'bar';
+		$ext_name = 'vendor3/bar';
 
 		$manager = $this->get_metadata_manager($ext_name);
 
@@ -98,7 +98,7 @@ class phpbb_extension_metadata_manager_test extends phpbb_database_test_case
 	// Should be the same as a direct json_decode of the composer.json file
 	public function test_foo()
 	{
-		$ext_name = 'foo';
+		$ext_name = 'vendor2/foo';
 
 		$manager = $this->get_metadata_manager($ext_name);
 
@@ -111,7 +111,7 @@ class phpbb_extension_metadata_manager_test extends phpbb_database_test_case
 			$this->fail($e);
 		}
 
-		$json = json_decode(file_get_contents($this->phpbb_root_path . 'ext/foo/composer.json'), true);
+		$json = json_decode(file_get_contents($this->phpbb_root_path . 'ext/vendor2/foo/composer.json'), true);
 
 		$this->assertEquals($metadata, $json);
 	}
diff --git a/tests/extension/modules_test.php b/tests/extension/modules_test.php
index ef21c943c2..5dcb24c691 100644
--- a/tests/extension/modules_test.php
+++ b/tests/extension/modules_test.php
@@ -7,10 +7,10 @@
 *
 */
 
-require_once dirname(__FILE__) . '/ext/foo/acp/a_info.php';
-require_once dirname(__FILE__) . '/ext/foo/mcp/a_info.php';
-require_once dirname(__FILE__) . '/ext/foo/acp/fail_info.php';
-require_once dirname(__FILE__) . '/ext/barfoo/acp/a_info.php';
+require_once dirname(__FILE__) . '/ext/vendor2/foo/acp/a_info.php';
+require_once dirname(__FILE__) . '/ext/vendor2/foo/mcp/a_info.php';
+require_once dirname(__FILE__) . '/ext/vendor2/foo/acp/fail_info.php';
+require_once dirname(__FILE__) . '/ext/vendor2/bar/acp/a_info.php';
 require_once dirname(__FILE__) . '/../../phpBB/includes/acp/acp_modules.php';
 
 class phpbb_extension_modules_test extends phpbb_test_case
@@ -25,15 +25,15 @@ class phpbb_extension_modules_test extends phpbb_test_case
 		$this->extension_manager = new phpbb_mock_extension_manager(
 			dirname(__FILE__) . '/',
 			array(
-				'foo' => array(
-					'ext_name' => 'foo',
+				'vendor2/foo' => array(
+					'ext_name' => 'vendor2/foo',
 					'ext_active' => '1',
-					'ext_path' => 'ext/foo/',
+					'ext_path' => 'ext/vendor2/foo/',
 				),
-				'bar' => array(
-					'ext_name' => 'bar',
+				'vendor3/bar' => array(
+					'ext_name' => 'vendor3/bar',
 					'ext_active' => '1',
-					'ext_path' => 'ext/bar/',
+					'ext_path' => 'ext/vendor3/bar/',
 				),
 			));
 		$phpbb_extension_manager = $this->extension_manager;
@@ -54,8 +54,8 @@ class phpbb_extension_modules_test extends phpbb_test_case
 		$this->acp_modules->module_class = 'acp';
 		$acp_modules = $this->acp_modules->get_module_infos();
 		$this->assertEquals(array(
-				'foo\\acp\\a_module' => array(
-					'filename'	=> 'foo\\acp\\a_module',
+				'vendor2\\foo\\acp\\a_module' => array(
+					'filename'	=> 'vendor2\\foo\\acp\\a_module',
 					'title'		=> 'Foobar',
 					'version'	=> '3.1.0-dev',
 					'modes'		=> array(
@@ -76,8 +76,8 @@ class phpbb_extension_modules_test extends phpbb_test_case
 		$this->acp_modules->module_class = 'mcp';
 		$acp_modules = $this->acp_modules->get_module_infos();
 		$this->assertEquals(array(
-				'foo\\mcp\\a_module' => array(
-					'filename'	=> 'foo\\mcp\\a_module',
+				'vendor2\\foo\\mcp\\a_module' => array(
+					'filename'	=> 'vendor2\\foo\\mcp\\a_module',
 					'title'		=> 'Foobar',
 					'version'	=> '3.1.0-dev',
 					'modes'		=> array(
@@ -90,8 +90,8 @@ class phpbb_extension_modules_test extends phpbb_test_case
 		$this->acp_modules->module_class = 'mcp';
 		$acp_modules = $this->acp_modules->get_module_infos('mcp_a_module');
 		$this->assertEquals(array(
-				'foo\\mcp\\a_module' => array(
-					'filename'	=> 'foo\\mcp\\a_module',
+				'vendor2\\foo\\mcp\\a_module' => array(
+					'filename'	=> 'vendor2\\foo\\mcp\\a_module',
 					'title'		=> 'Foobar',
 					'version'	=> '3.1.0-dev',
 					'modes'		=> array(
@@ -104,8 +104,8 @@ class phpbb_extension_modules_test extends phpbb_test_case
 		$this->acp_modules->module_class = '';
 		$acp_modules = $this->acp_modules->get_module_infos('mcp_a_module', 'mcp');
 		$this->assertEquals(array(
-				'foo\\mcp\\a_module' => array(
-					'filename'	=> 'foo\\mcp\\a_module',
+				'vendor2\\foo\\mcp\\a_module' => array(
+					'filename'	=> 'vendor2\\foo\\mcp\\a_module',
 					'title'		=> 'Foobar',
 					'version'	=> '3.1.0-dev',
 					'modes'		=> array(
@@ -128,8 +128,8 @@ class phpbb_extension_modules_test extends phpbb_test_case
 		$this->acp_modules->module_class = 'acp';
 		$acp_modules = $this->acp_modules->get_module_infos('foo_acp_a_module');
 		$this->assertEquals(array(
-				'foo\\acp\\a_module' => array (
-					'filename' => 'foo\\acp\\a_module',
+				'vendor2\\foo\\acp\\a_module' => array (
+					'filename' => 'vendor2\\foo\\acp\\a_module',
 					'title' => 'Foobar',
 					'version' => '3.1.0-dev',
 					'modes' => array (
@@ -148,12 +148,12 @@ class phpbb_extension_modules_test extends phpbb_test_case
 		$this->assertEquals(array(), $acp_modules);
 
 		// No specific module, module class set to false (will default to the above acp)
-		// Setting $use_all_available will cause get_module_infos() to also load not enabled extensions (barfoo)
+		// Setting $use_all_available will cause get_module_infos() to also load not enabled extensions (vendor2/bar)
 		$this->acp_modules->module_class = 'acp';
 		$acp_modules = $this->acp_modules->get_module_infos('', false, true);
 		$this->assertEquals(array(
-				'foo\\acp\\a_module' => array(
-					'filename'	=> 'foo\\acp\\a_module',
+				'vendor2\\foo\\acp\\a_module' => array(
+					'filename'	=> 'vendor2\\foo\\acp\\a_module',
 					'title'		=> 'Foobar',
 					'version'	=> '3.1.0-dev',
 					'modes'		=> array(
@@ -168,9 +168,9 @@ class phpbb_extension_modules_test extends phpbb_test_case
 						'test'		=> array('title' => 'Test', 'auth' => '', 'cat' => array('ACP_GENERAL')),
 					),
 				),
-				'barfoo\\acp\\a_module' => array(
-					'filename'	=> 'barfoo\\acp\\a_module',
-					'title'		=> 'Barfoo',
+				'vendor2\\bar\\acp\\a_module' => array(
+					'filename'	=> 'vendor2\\bar\\acp\\a_module',
+					'title'		=> 'Bar',
 					'version'	=> '3.1.0-dev',
 					'modes'		=> array(
 						'config'		=> array('title' => 'Config',	'auth' => '', 'cat' => array('ACP_MODS')),
@@ -179,11 +179,11 @@ class phpbb_extension_modules_test extends phpbb_test_case
 			), $acp_modules);
 
 		// Specific module set to disabled extension
-		$acp_modules = $this->acp_modules->get_module_infos('barfoo_acp_a_module', 'acp', true);
+		$acp_modules = $this->acp_modules->get_module_infos('vendor2_bar_acp_a_module', 'acp', true);
 		$this->assertEquals(array(
-				'barfoo\\acp\\a_module' => array(
-					'filename'	=> 'barfoo\\acp\\a_module',
-					'title'		=> 'Barfoo',
+				'vendor2\\bar\\acp\\a_module' => array(
+					'filename'	=> 'vendor2\\bar\\acp\\a_module',
+					'title'		=> 'Bar',
 					'version'	=> '3.1.0-dev',
 					'modes'		=> array(
 						'config'		=> array('title' => 'Config',	'auth' => '', 'cat' => array('ACP_MODS')),
diff --git a/tests/functional/extension_acp_test.php b/tests/functional/extension_acp_test.php
index 5d391e42f7..53f62c4f19 100644
--- a/tests/functional/extension_acp_test.php
+++ b/tests/functional/extension_acp_test.php
@@ -45,7 +45,7 @@ class phpbb_functional_extension_acp_test extends phpbb_functional_test_case
 		// Insert our base data
 		$insert_rows = array(
 			array(
-				'ext_name'		=> 'foo',
+				'ext_name'		=> 'vendor2/foo',
 				'ext_active'	=> true,
 				'ext_state'		=> 'b:0;',
 			),
@@ -57,12 +57,12 @@ class phpbb_functional_extension_acp_test extends phpbb_functional_test_case
 
 			// do not exist
 			array(
-				'ext_name'		=> 'test2',
+				'ext_name'		=> 'vendor/test2',
 				'ext_active'	=> true,
 				'ext_state'		=> 'b:0;',
 			),
 			array(
-				'ext_name'		=> 'test3',
+				'ext_name'		=> 'vendor/test3',
 				'ext_active'	=> false,
 				'ext_state'		=> 'b:0;',
 			),
@@ -80,30 +80,38 @@ class phpbb_functional_extension_acp_test extends phpbb_functional_test_case
 		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&sid=' . $this->sid);
 
 		$this->assertCount(1, $crawler->filter('.ext_enabled'));
-		$this->assertCount(5, $crawler->filter('.ext_disabled'));
+		$this->assertCount(4, $crawler->filter('.ext_disabled'));
 
 		$this->assertContains('phpBB Foo Extension', $crawler->filter('.ext_enabled')->eq(0)->text());
 		$this->assertContainsLang('EXTENSION_DISABLE', $crawler->filter('.ext_enabled')->eq(0)->text());
 
-		$this->assertContains('The “test2” extension is not valid.', $crawler->filter('.ext_disabled')->eq(0)->text());
+		$this->assertContains('phpBB Moo Extension', $crawler->filter('.ext_disabled')->eq(1)->text());
+		$this->assertContainsLang('DETAILS', $crawler->filter('.ext_disabled')->eq(1)->text());
+		$this->assertContainsLang('EXTENSION_ENABLE', $crawler->filter('.ext_disabled')->eq(1)->text());
+		$this->assertContainsLang('EXTENSION_DELETE_DATA', $crawler->filter('.ext_disabled')->eq(1)->text());
 
-		$this->assertContains('The “test3” extension is not valid.', $crawler->filter('.ext_disabled')->eq(1)->text());
+		$this->assertContains('The “vendor/test2” extension is not valid.', $crawler->filter('.ext_disabled')->eq(0)->text());
 
-		$this->assertContains('phpBB Moo Extension', $crawler->filter('.ext_disabled')->eq(2)->text());
-		$this->assertContainsLang('DETAILS', $crawler->filter('.ext_disabled')->eq(2)->text());
-		$this->assertContainsLang('EXTENSION_ENABLE', $crawler->filter('.ext_disabled')->eq(2)->text());
-		$this->assertContainsLang('EXTENSION_DELETE_DATA', $crawler->filter('.ext_disabled')->eq(2)->text());
+		$this->assertContains('The “vendor/test3” extension is not valid.', $crawler->filter('.ext_disabled')->eq(2)->text());
 
-		$this->assertContains('The “bar” extension is not valid.', $crawler->filter('.ext_disabled')->eq(3)->text());
+		$this->assertContains('phpBB Bar Extension', $crawler->filter('.ext_disabled')->eq(3)->text());
+		$this->assertContainsLang('DETAILS', $crawler->filter('.ext_disabled')->eq(3)->text());
+		$this->assertContainsLang('EXTENSION_ENABLE', $crawler->filter('.ext_disabled')->eq(3)->text());
+
+		// Check that invalid extensions are not listed.
+		$this->assertNotContains('phpBB BarFoo Extension', $crawler->filter('.table1')->text());
+		$this->assertNotContains('barfoo', $crawler->filter('.table1')->text());
+
+		$this->assertNotContains('vendor3/bar', $crawler->filter('.table1')->text());
 	}
 
 	public function test_details()
 	{
-		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=details&ext_name=foo&sid=' . $this->sid);
+		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=details&ext_name=vendor2%2Ffoo&sid=' . $this->sid);
 
 		$validation = array(
 			'DISPLAY_NAME'		=> 'phpBB Foo Extension',
-			'CLEAN_NAME'		=> 'foo/example',
+			'CLEAN_NAME'		=> 'vendor2/foo',
 			'TYPE'				=> 'phpbb-extension',
 			'DESCRIPTION'		=> 'An example/sample extension to be used for testing purposes in phpBB Development.',
 			'VERSION'	  		=> '1.0.0',
@@ -143,7 +151,7 @@ class phpbb_functional_extension_acp_test extends phpbb_functional_test_case
 	public function test_enable_pre()
 	{
 		// Foo is already enabled (redirect to list)
-		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=enable_pre&ext_name=foo&sid=' . $this->sid);
+		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=enable_pre&ext_name=vendor2%2Ffoo&sid=' . $this->sid);
 		$this->assertContainsLang('EXTENSION_NAME', $crawler->filter('div.main thead')->text());
 		$this->assertContainsLang('EXTENSION_OPTIONS', $crawler->filter('div.main thead')->text());
 		$this->assertContainsLang('EXTENSION_ACTIONS', $crawler->filter('div.main thead')->text());
@@ -160,7 +168,7 @@ class phpbb_functional_extension_acp_test extends phpbb_functional_test_case
 		$this->assertContainsLang('EXTENSION_OPTIONS', $crawler->filter('div.main thead')->text());
 		$this->assertContainsLang('EXTENSION_ACTIONS', $crawler->filter('div.main thead')->text());
 
-		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=disable_pre&ext_name=foo&sid=' . $this->sid);
+		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=disable_pre&ext_name=vendor2%2Ffoo&sid=' . $this->sid);
 		$this->assertContains($this->lang('EXTENSION_DISABLE_CONFIRM', 'phpBB Foo Extension'), $crawler->filter('.errorbox')->text());
 	}
 
@@ -171,7 +179,7 @@ class phpbb_functional_extension_acp_test extends phpbb_functional_test_case
 		$this->assertContains('The required file does not exist', $crawler->filter('.errorbox')->text());
 
 		// foo is not disabled (redirect to list)
-		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=delete_data_pre&ext_name=foo&sid=' . $this->sid);
+		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=delete_data_pre&ext_name=vendor2%2Ffoo&sid=' . $this->sid);
 		$this->assertContainsLang('EXTENSION_NAME', $crawler->filter('div.main thead')->text());
 		$this->assertContainsLang('EXTENSION_OPTIONS', $crawler->filter('div.main thead')->text());
 		$this->assertContainsLang('EXTENSION_ACTIONS', $crawler->filter('div.main thead')->text());
@@ -211,5 +219,9 @@ class phpbb_functional_extension_acp_test extends phpbb_functional_test_case
 		$form = $crawler->selectButton('delete_data')->form();
 		$crawler = self::submit($form);
 		$this->assertContainsLang('EXTENSION_DELETE_DATA_SUCCESS', $crawler->filter('.successbox')->text());
+
+		// Attempt to enable invalid extension
+		$crawler = self::request('GET', 'adm/index.php?i=acp_extensions&mode=main&action=enable_pre&ext_name=barfoo&sid=' . $this->sid);
+		$this->assertContainsLang('EXTENSION_DIR_INVALID', $crawler->filter('.errorbox')->text());
 	}
 }