MAGETWO-38031: [GITHUB] Allow modules to live outside of app/code directory #1206

 - more description in docblocks

Author: Dale Sikkema

lib/internal/Magento/Framework/Module/Dir.php

@@ -15,6 +15,15 @@
 
 class Dir
 {
+    /**#@+
+     * Directories within modules
+     */
+    const MODULE_ETC_DIR = 'etc';
+    const MODULE_I18N_DIR = 'i18n';
+    const MODULE_VIEW_DIR = 'view';
+    const MODULE_CONTROLLER_DIR = 'Controller';
+    /**#@-*/
+
     /**
      * Modules root directory
      *
@@ -63,9 +72,14 @@ public function getDir($moduleName, $type = '')
             $relativePath = $this->_string->upperCaseWords($moduleName, '_', '/');
             $path = $this->_modulesDirectory->getAbsolutePath($relativePath);
         }
-        
+
         if ($type) {
-            if (!in_array($type, ['etc', 'i18n', 'view', 'Controller'])) {
+            if (!in_array($type, [
+                self::MODULE_ETC_DIR,
+                self::MODULE_I18N_DIR,
+                self::MODULE_VIEW_DIR,
+                self::MODULE_CONTROLLER_DIR
+            ])) {
                 throw new \InvalidArgumentException("Directory type '{$type}' is not recognized.");
             }
             $path .= '/' . $type;

lib/internal/Magento/Framework/Module/ModuleRegistryInterface.php

@@ -11,7 +11,7 @@
 interface ModuleRegistryInterface
 {
     /**
-     * Get list of Magento module paths
+     * Get list of registered Magento module paths
      *
      * Returns an array where key is fully-qualified module name and value is absolute path to module
      *
@@ -20,6 +20,8 @@ interface ModuleRegistryInterface
     public function getModulePaths();
 
     /**
+     * Get path of a module if it is already registered
+     *
      * @param string $moduleName
      * @return null|string
      */

lib/internal/Magento/Framework/Module/Registrar.php

@@ -6,7 +6,8 @@
 namespace Magento\Framework\Module;
 
 /**
- * Provides ability to statically register modules which do not reside in the modules directory
+ * Provides ability to statically register modules which do not reside in the modules directory. Not all modules
+ * will be registered by default.
  *
  * @author Josh Di Fabio <[email protected]>
  */