Merge "Allow reset of global services (redux)."

diff --combined includes/GlobalFunctions.php
index b5de66f,8c55d9a..537bdef
--- 1/includes/GlobalFunctions.php
--- 2/includes/GlobalFunctions.php
+++ b/includes/GlobalFunctions.php
@@@ -501,26 -501,12 +501,26 @@@ function wfAppendQuery( $url, $query ) 
                $query = wfArrayToCgi( $query );
        }
        if ( $query != '' ) {
 +              // Remove the fragment, if there is one
 +              $fragment = false;
 +              $hashPos = strpos( $url, '#' );
 +              if ( $hashPos !== false ) {
 +                      $fragment = substr( $url, $hashPos );
 +                      $url = substr( $url, 0, $hashPos );
 +              }
 +
 +              // Add parameter
                if ( false === strpos( $url, '?' ) ) {
                        $url .= '?';
                } else {
                        $url .= '&';
                }
                $url .= $query;
 +
 +              // Put the fragment back
 +              if ( $fragment !== false ) {
 +                      $url .= $fragment;
 +              }
        }
        return $url;
  }
@@@ -3123,6 -3109,9 +3123,9 @@@ function wfSplitWikiID( $wiki ) 
   * Note 2: use $this->getDB() in maintenance scripts that may be invoked by
   * updater to ensure that a proper database is being updated.
   *
+  * @todo Replace calls to wfGetDB with calls to LoadBalancer::getConnection()
+  *       on an injected instance of LoadBalancer.
+  *
   * @return DatabaseBase
   */
  function wfGetDB( $db, $groups = [], $wiki = false ) {
@@@ -3132,20 -3121,30 +3135,30 @@@
  /**
   * Get a load balancer object.
   *
+  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancer()
+  *              or MediaWikiServices::getDBLoadBalancerFactory() instead.
+  *
   * @param string|bool $wiki Wiki ID, or false for the current wiki
   * @return LoadBalancer
   */
  function wfGetLB( $wiki = false ) {
-       return wfGetLBFactory()->getMainLB( $wiki );
+       if ( $wiki === false ) {
+               return \MediaWiki\MediaWikiServices::getInstance()->getDBLoadBalancer();
+       } else {
+               $factory = \MediaWiki\MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
+               return $factory->getMainLB( $wiki );
+       }
  }
  
  /**
   * Get the load balancer factory object
   *
+  * @deprecated since 1.27, use MediaWikiServices::getDBLoadBalancerFactory() instead.
+  *
   * @return LBFactory
   */
  function wfGetLBFactory() {
-       return LBFactory::singleton();
+       return \MediaWiki\MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
  }
  
  /**

diff --combined includes/installer/Installer.php
index d747707,97214da..a9f219f
--- 1/includes/installer/Installer.php
--- 2/includes/installer/Installer.php
+++ b/includes/installer/Installer.php
@@@ -351,37 -351,67 +351,67 @@@ abstract class Installer 
         */
        abstract public function showStatusMessage( Status $status );
  
+       /**
+        * Constructs a Config object that contains configuration settings that should be
+        * overwritten for the installation process.
+        *
+        * @since 1.27
+        *
+        * @param Config $baseConfig
+        *
+        * @return Config The config to use during installation.
+        */
+       public static function getInstallerConfig( Config $baseConfig ) {
+               $configOverrides = new HashConfig();
+ 
+               // disable (problematic) object cache types explicitly, preserving all other (working) ones
+               // bug T113843
+               $emptyCache = [ 'class' => 'EmptyBagOStuff' ];
+ 
+               $objectCaches = [
+                               CACHE_NONE => $emptyCache,
+                               CACHE_DB => $emptyCache,
+                               CACHE_ANYTHING => $emptyCache,
+                               CACHE_MEMCACHED => $emptyCache,
+                       ] + $baseConfig->get( 'ObjectCaches' );
+ 
+               $configOverrides->set( 'ObjectCaches', $objectCaches );
+ 
+               // Load the installer's i18n.
+               $messageDirs = $baseConfig->get( 'MessagesDirs' );
+               $messageDirs['MediawikiInstaller'] = __DIR__ . '/i18n';
+ 
+               $configOverrides->set( 'MessagesDirs', $messageDirs );
+ 
+               return new MultiConfig( [ $configOverrides, $baseConfig ] );
+       }
+ 
        /**
         * Constructor, always call this from child classes.
         */
        public function __construct() {
-               global $wgMessagesDirs, $wgUser;
+               global $wgMemc, $wgUser;
+ 
+               $defaultConfig = new GlobalVarConfig(); // all the stuff from DefaultSettings.php
+               $installerConfig = self::getInstallerConfig( $defaultConfig );
+ 
+               // Reset all services and inject config overrides
+               MediaWiki\MediaWikiServices::resetGlobalInstance( $installerConfig );
  
                // Don't attempt to load user language options (T126177)
                // This will be overridden in the web installer with the user-specified language
                RequestContext::getMain()->setLanguage( 'en' );
  
                // Disable the i18n cache
+               // TODO: manage LocalisationCache singleton in MediaWikiServices
                Language::getLocalisationCache()->disableBackend();
-               // Disable LoadBalancer and wfGetDB etc.
-               LBFactory::disableBackend();
+ 
+               // Disable all global services, since we don't have any configuration yet!
+               MediaWiki\MediaWikiServices::disableStorageBackend();
  
                // Disable object cache (otherwise CACHE_ANYTHING will try CACHE_DB and
                // SqlBagOStuff will then throw since we just disabled wfGetDB)
-               $GLOBALS['wgMemc'] = new EmptyBagOStuff;
-               ObjectCache::clear();
-               $emptyCache = [ 'class' => 'EmptyBagOStuff' ];
-               // disable (problematic) object cache types explicitly, preserving all other (working) ones
-               // bug T113843
-               $GLOBALS['wgObjectCaches'] = [
-                       CACHE_NONE => $emptyCache,
-                       CACHE_DB => $emptyCache,
-                       CACHE_ANYTHING => $emptyCache,
-                       CACHE_MEMCACHED => $emptyCache,
-               ] + $GLOBALS['wgObjectCaches'];
- 
-               // Load the installer's i18n.
-               $wgMessagesDirs['MediawikiInstaller'] = __DIR__ . '/i18n';
+               $wgMemc = ObjectCache::getInstance( CACHE_NONE );
  
                // Having a user with id = 0 safeguards us from DB access via User::loadOptions().
                $wgUser = User::newFromId( 0 );
@@@ -1697,7 -1727,7 +1727,7 @@@
                                wfMessage( 'mainpagedocfooter' )->inContentLanguage()->text()
                        );
  
 -                      $page->doEditContent( $content,
 +                      $status = $page->doEditContent( $content,
                                '',
                                EDIT_NEW,
                                false,