Fix type issues with root package interface

src/Composer/Command/UpdateCommand.php

@@ -17,7 +17,6 @@ use Composer\DependencyResolver\Request;
 use Composer\Installer;
 use Composer\IO\IOInterface;
 use Composer\Package\Loader\RootPackageLoader;
-use Composer\Package\RootPackage;
 use Composer\Plugin\CommandEvent;
 use Composer\Plugin\PluginEvents;
 use Composer\Package\Version\VersionParser;
@@ -156,9 +155,7 @@ EOT
         }
         $rootPackage->setRequires($rootRequires);
         $rootPackage->setDevRequires($rootDevRequires);
-        if ($rootPackage instanceof RootPackage) {
         $rootPackage->setReferences(RootPackageLoader::extractReferences($reqs, $rootPackage->getReferences()));
-        }
         $rootPackage->setStabilityFlags(RootPackageLoader::extractStabilityFlags($reqs, $rootPackage->getMinimumStability(), $rootPackage->getStabilityFlags()));
 
         if ($input->getOption('interactive')) {

src/Composer/Package/RootAliasPackage.php

@@ -159,6 +159,46 @@ class RootAliasPackage extends CompleteAliasPackage implements RootPackageInterf
         $this->aliasOf->setStabilityFlags($stabilityFlags);
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    public function setMinimumStability($minimumStability)
+    {
+        $this->aliasOf->setMinimumStability($minimumStability);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setPreferStable($preferStable)
+    {
+        $this->aliasOf->setPreferStable($preferStable);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setConfig(array $config)
+    {
+        $this->aliasOf->setConfig($config);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setReferences(array $references)
+    {
+        $this->aliasOf->setReferences($references);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function setAliases(array $aliases)
+    {
+        $this->aliasOf->setAliases($aliases);
+    }
+
     /**
      * {@inheritDoc}
      */

src/Composer/Package/RootPackage.php

@@ -29,9 +29,7 @@ class RootPackage extends CompletePackage implements RootPackageInterface
     protected $aliases = array();
 
     /**
-     * Set the minimumStability
-     *
-     * @param string $minimumStability
+     * {@inerhitDoc}
      */
     public function setMinimumStability($minimumStability)
     {
@@ -47,9 +45,7 @@ class RootPackage extends CompletePackage implements RootPackageInterface
     }
 
     /**
-     * Set the stabilityFlags
-     *
-     * @param array $stabilityFlags
+     * {@inheritDoc}
      */
     public function setStabilityFlags(array $stabilityFlags)
     {
@@ -65,9 +61,7 @@ class RootPackage extends CompletePackage implements RootPackageInterface
     }
 
     /**
-     * Set the preferStable
-     *
-     * @param bool $preferStable
+     * {@inerhitDoc}
      */
     public function setPreferStable($preferStable)
     {
@@ -83,9 +77,7 @@ class RootPackage extends CompletePackage implements RootPackageInterface
     }
 
     /**
-     * Set the config
-     *
-     * @param array $config
+     * {@inerhitDoc}
      */
     public function setConfig(array $config)
     {
@@ -101,9 +93,7 @@ class RootPackage extends CompletePackage implements RootPackageInterface
     }
 
     /**
-     * Set the references
-     *
-     * @param array $references
+     * {@inerhitDoc}
      */
     public function setReferences(array $references)
     {
@@ -119,9 +109,7 @@ class RootPackage extends CompletePackage implements RootPackageInterface
     }
 
     /**
-     * Set the aliases
-     *
-     * @param array $aliases
+     * {@inerhitDoc}
      */
     public function setAliases(array $aliases)
     {

src/Composer/Package/RootPackageInterface.php

@@ -128,6 +128,41 @@ interface RootPackageInterface extends CompletePackageInterface
      */
     public function setStabilityFlags(array $stabilityFlags);
 
+    /**
+     * Set the minimumStability
+     *
+     * @param string $minimumStability
+     */
+    public function setMinimumStability($minimumStability);
+
+    /**
+     * Set the preferStable
+     *
+     * @param bool $preferStable
+     */
+    public function setPreferStable($preferStable);
+
+    /**
+     * Set the config
+     *
+     * @param array $config
+     */
+    public function setConfig(array $config);
+
+    /**
+     * Set the references
+     *
+     * @param array $references
+     */
+    public function setReferences(array $references);
+
+    /**
+     * Set the aliases
+     *
+     * @param array $aliases
+     */
+    public function setAliases(array $aliases);
+
     /**
      * Set the suggested packages
      *